ZSHCOMPSYS(1) General Commands Manual ZSHCOMPSYS(1)
NAME
zshcompsys - zsh completion system
DESCRIPTION
This describes the shell code for the `new' completion system, referred
to as compsys. It is written in shell functions based on the features
described in zshcompwid(1).
The features are contextual, sensitive to the point at which completion
is started. Many completions are already provided. For this reason, a
user can perform a great many tasks without knowing any details beyond
how to initialize the system, which is described below in INITIALIZA-
TION.
The context that decides what completion is to be performed may be
• an argument or option position: these describe the position on
the command line at which completion is requested. For example
`first argument to rmdir, the word being completed names a direc-
tory';
• a special context, denoting an element in the shell's syntax.
For example `a word in command position' or `an array subscript'.
A full context specification contains other elements, as we shall de-
scribe.
Besides commands names and contexts, the system employs two more con-
cepts, styles and tags. These provide ways for the user to configure
the system's behaviour.
Tags play a dual role. They serve as a classification system for the
matches, typically indicating a class of object that the user may need
to distinguish. For example, when completing arguments of the ls com-
mand the user may prefer to try files before directories, so both of
these are tags. They also appear as the rightmost element in a context
specification.
Styles modify various operations of the completion system, such as out-
put formatting, but also what kinds of completers are used (and in what
order), or which tags are examined. Styles may accept arguments and are
manipulated using the zstyle command described in zshmodules(1).
In summary, tags describe what the completion objects are, and style how
they are to be completed. At various points of execution, the comple-
tion system checks what styles and/or tags are defined for the current
context, and uses that to modify its behavior. The full description of
context handling, which determines how tags and other elements of the
context influence the behaviour of styles, is described below in COMPLE-
TION SYSTEM CONFIGURATION.
When a completion is requested, a dispatcher function is called; see the
description of _main_complete in the list of control functions below.
This dispatcher decides which function should be called to produce the
completions, and calls it. The result is passed to one or more com-
pleters, functions that implement individual completion strategies: sim-
ple completion, error correction, completion with error correction, menu
selection, etc.
More generally, the shell functions contained in the completion system
are of two types:
• those beginning `comp' are to be called directly; there are only
a few of these;
• those beginning `_' are called by the completion code. The shell
functions of this set, which implement completion behaviour and
may be bound to keystrokes, are referred to as `widgets'. These
proliferate as new completions are required.
INITIALIZATION
If the system was installed completely, it should be enough to call the
shell function compinit from your initialization file; see the next sec-
tion. However, the function compinstall can be run by a user to config-
ure various aspects of the completion system.
Usually, compinstall will insert code into .zshrc, although if that is
not writable it will save it in another file and tell you that file's
location. Note that it is up to you to make sure that the lines added
to .zshrc are actually run; you may, for example, need to move them to
an earlier place in the file if .zshrc usually returns early. So long
as you keep them all together (including the comment lines at the start
and finish), you can rerun compinstall and it will correctly locate and
modify these lines. Note, however, that any code you add to this sec-
tion by hand is likely to be lost if you rerun compinstall, although
lines using the command `zstyle' should be gracefully handled.
The new code will take effect next time you start the shell, or run
.zshrc by hand; there is also an option to make them take effect immedi-
ately. However, if compinstall has removed definitions, you will need
to restart the shell to see the changes.
To run compinstall you will need to make sure it is in a directory men-
tioned in your fpath parameter, which should already be the case if zsh
was properly configured as long as your startup files do not remove the
appropriate directories from fpath. Then it must be autoloaded (`au-
toload -U compinstall' is recommended). You can abort the installation
any time you are being prompted for information, and your .zshrc will
not be altered at all; changes only take place right at the end, where
you are specifically asked for confirmation.
Use of compinit
This section describes the use of compinit to initialize completion for
the current session when called directly; if you have run compinstall it
will be called automatically from your .zshrc.
To initialize the system, the function compinit should be in a directory
mentioned in the fpath parameter, and should be autoloaded (`autoload -U
compinit' is recommended), and then run simply as `compinit'. This will
define a few utility functions, arrange for all the necessary shell
functions to be autoloaded, and will then re-define all widgets that do
completion to use the new system. If you use the menu-select widget,
which is part of the zsh/complist module, you should make sure that that
module is loaded before the call to compinit so that that widget is also
re-defined. If completion styles (see below) are set up to perform ex-
pansion as well as completion by default, and the TAB key is bound to
expand-or-complete, compinit will rebind it to complete-word; this is
necessary to use the correct form of expansion.
Should you need to use the original completion commands, you can still
bind keys to the old widgets by putting a `.' in front of the widget
name, e.g. `.expand-or-complete'.
To speed up the running of compinit, it can be made to produce a dumped
configuration that will be read in on future invocations; this is the
default, but can be turned off by calling compinit with the option -D.
The dumped file is .zcompdump in the same directory as the startup files
(i.e. $ZDOTDIR or $HOME); alternatively, an explicit file name can be
given by `compinit -d dumpfile'. The next invocation of compinit will
read the dumped file instead of performing a full initialization.
If the number of completion files changes, compinit will recognise this
and produce a new dump file. However, if the name of a function or the
arguments in the first line of a #compdef function (as described below)
change, it is easiest to delete the dump file by hand so that compinit
will re-create it the next time it is run. The check performed to see
if there are new functions can be omitted by giving the option -C. In
this case the dump file will only be created if there isn't one already.
The dumping is actually done by another function, compdump, but you will
only need to run this yourself if you change the configuration (e.g. us-
ing compdef) and then want to dump the new one. The name of the old
dumped file will be remembered for this purpose.
If the parameter _compdir is set, compinit uses it as a directory where
completion functions can be found; this is only necessary if they are
not already in the function search path.
For security reasons compinit also checks if the completion system would
use files not owned by root or by the current user, or files in directo-
ries that are world- or group-writable or that are not owned by root or
by the current user. If such files or directories are found, compinit
will ask if the completion system should really be used. To avoid these
tests and make all files found be used without asking, use the option
-u, and to make compinit silently ignore all insecure files and directo-
ries use the option -i. This security check is skipped entirely when
the -C option is given, provided the dumpfile exists.
The security check can be retried at any time by running the function
compaudit. This is the same check used by compinit, but when it is exe-
cuted directly any changes to fpath are made local to the function so
they do not persist. The directories to be checked may be passed as ar-
guments; if none are given, compaudit uses fpath and _compdir to find
completion system directories, adding missing ones to fpath as neces-
sary. To force a check of exactly the directories currently named in
fpath, set _compdir to an empty string before calling compaudit or
compinit.
The function bashcompinit provides compatibility with bash's programma-
ble completion system. When run it will define the functions, compgen
and complete which correspond to the bash builtins with the same names.
It will then be possible to use completion specifications and functions
written for bash.
Autoloaded files
The convention for autoloaded functions used in completion is that they
start with an underscore; as already mentioned, the fpath/FPATH parame-
ter must contain the directory in which they are stored. If zsh was
properly installed on your system, then fpath/FPATH automatically con-
tains the required directories for the standard functions.
For incomplete installations, if compinit does not find enough files be-
ginning with an underscore (fewer than twenty) in the search path, it
will try to find more by adding the directory _compdir to the search
path. If that directory has a subdirectory named Base, all subdirecto-
ries will be added to the path. Furthermore, if the subdirectory Base
has a subdirectory named Core, compinit will add all subdirectories of
the subdirectories to the path: this allows the functions to be in the
same format as in the zsh source distribution.
When compinit is run, it searches all such files accessible via
fpath/FPATH and reads the first line of each of them. This line should
contain one of the tags described below. Files whose first line does
not start with one of these tags are not considered to be part of the
completion system and will not be treated specially.
The tags are:
#compdef name ... [ -{p|P} pattern ... [ -N name ... ] ]
The file will be made autoloadable and the function defined in it
will be called when completing names, each of which is either the
name of a command whose arguments are to be completed or one of a
number of special contexts in the form -context- described below.
Each name may also be of the form `cmd=service'. When completing
the command cmd, the function typically behaves as if the command
(or special context) service was being completed instead. This
provides a way of altering the behaviour of functions that can
perform many different completions. It is implemented by setting
the parameter $service when calling the function; the function
may choose to interpret this how it wishes, and simpler functions
will probably ignore it.
If the #compdef line contains one of the options -p or -P, the
words following are taken to be patterns. The function will be
called when completion is attempted for a command or context that
matches one of the patterns. The options -p and -P are used to
specify patterns to be tried before or after other completions
respectively. Hence -P may be used to specify default actions.
The option -N is used after a list following -p or -P; it speci-
fies that remaining words no longer define patterns. It is pos-
sible to toggle between the three options as many times as neces-
sary.
#compdef -k style key-sequence ...
This option creates a widget behaving like the builtin widget
style and binds it to the given key-sequences, if any. The style
must be one of the builtin widgets that perform completion,
namely complete-word, delete-char-or-list, expand-or-complete,
expand-or-complete-prefix, list-choices, menu-complete, menu-ex-
pand-or-complete, or reverse-menu-complete. If the zsh/complist
module is loaded (see zshmodules(1)) the widget menu-select is
also available.
When one of the key-sequences is typed, the function in the file
will be invoked to generate the matches. Note that a key will
not be re-bound if it already was (that is, was bound to some-
thing other than undefined-key). The widget created has the same
name as the file and can be bound to any other keys using bindkey
as usual.
#compdef -K widget-name style key-sequence [ name style seq ... ]
This is similar to -k except that only one key-sequence argument
may be given for each widget-name style pair. However, the en-
tire set of three arguments may be repeated with a different set
of arguments. Note in particular that the widget-name must be
distinct in each set. If it does not begin with `_' this will be
added. The widget-name should not clash with the name of any ex-
isting widget: names based on the name of the function are most
useful. For example,
#compdef -K _foo_complete complete-word "^X^C" \
_foo_list list-choices "^X^D"
(all on one line) defines a widget _foo_complete for completion,
bound to `^X^C', and a widget _foo_list for listing, bound to
`^X^D'.
#autoload [ options ]
Functions with the #autoload tag are marked for autoloading but
are not otherwise treated specially. Typically they are to be
called from within one of the completion functions. Any options
supplied will be passed to the autoload builtin; a typical use is
+X to force the function to be loaded immediately. Note that the
-U and -z flags are always added implicitly.
The # is part of the tag name and no white space is allowed after it.
The #compdef tags use the compdef function described below; the main
difference is that the name of the function is supplied implicitly.
The special contexts for which completion functions can be defined are:
-array-value-
The right hand side of an array-assignment (`name=(...)')
-assign-parameter-
The name of a parameter in an assignment, i.e. on the left hand
side of an `='
-brace-parameter-
The name of a parameter expansion within braces (`${...}')
-command-
A word in command position
-condition-
A word inside a condition (`[[...]]')
-default-
Any word for which no other completion is defined
-equal-
A word beginning with an equals sign
-first-
This is tried before any other completion function. The function
called may set the _compskip parameter to one of various values:
all: no further completion is attempted; a string containing the
substring patterns: no pattern completion functions will be
called; a string containing default: the function for the `-de-
fault-' context will not be called, but functions defined for
commands will be.
-math- Inside mathematical contexts, such as `((...))'
-parameter-
The name of a parameter expansion (`$...')
-redirect-
The word after a redirection operator.
-subscript-
The contents of a parameter subscript.
-tilde-
After an initial tilde (`~'), but before the first slash in the
word.
-value-
On the right hand side of an assignment.
Default implementations are supplied for each of these contexts. In
most cases the context -context- is implemented by a corresponding func-
tion _context, for example the context `-tilde-' and the function
`_tilde').
The contexts -redirect- and -value- allow extra context-specific infor-
mation. (Internally, this is handled by the functions for each context
calling the function _dispatch.) The extra information is added sepa-
rated by commas.
For the -redirect- context, the extra information is in the form `-redi-
rect-,op,command', where op is the redirection operator and command is
the name of the command on the line. If there is no command on the line
yet, the command field will be empty.
For the -value- context, the form is `-value-,name,command', where name
is the name of the parameter on the left hand side of the assignment.
In the case of elements of an associative array, for example `assoc=(key
<TAB>', name is expanded to `name-key'. In certain special contexts,
such as completing after `make CFLAGS=', the command part gives the name
of the command, here make; otherwise it is empty.
It is not necessary to define fully specific completions as the func-
tions provided will try to generate completions by progressively replac-
ing the elements with `-default-'. For example, when completing after
`foo=<TAB>', _value will try the names `-value-,foo,' (note the empty
command part), `-value-,foo,-default-' and`-value-,-default-,-default-',
in that order, until it finds a function to handle the context.
As an example:
compdef '_files -g "*.log"' '-redirect-,2>,-default-'
completes files matching `*.log' after `2> <TAB>' for any command with
no more specific handler defined.
Also:
compdef _foo -value-,-default-,-default-
specifies that _foo provides completions for the values of parameters
for which no special function has been defined. This is usually handled
by the function _value itself.
The same lookup rules are used when looking up styles (as described be-
low); for example
zstyle ':completion:*:*:-redirect-,2>,*:*' file-patterns '*.log'
is another way to make completion after `2> <TAB>' complete files match-
ing `*.log'.
Functions
The following function is defined by compinit and may be called di-
rectly.
compdef [ -ane ] function name ... [ -{p|P} pattern ... [ -N name ...]]
compdef -d name ...
compdef -k [ -an ] function style key-sequence [ key-sequence ... ]
compdef -K [ -an ] function name style key-seq [ name style seq ... ]
The first form defines the function to call for completion in the
given contexts as described for the #compdef tag above.
Alternatively, all the arguments may have the form `cmd=service'.
Here service should already have been defined by `cmd1=service'
lines in #compdef files, as described above. The argument for
cmd will be completed in the same way as service.
The function argument may alternatively be a string containing
almost any shell code. If the string contains an equal sign, the
above will take precedence. The option -e may be used to specify
the first argument is to be evaluated as shell code even if it
contains an equal sign. The string will be executed using the
eval builtin command to generate completions. This provides a
way of avoiding having to define a new completion function. For
example, to complete files ending in `.h' as arguments to the
command foo:
compdef '_files -g "*.h"' foo
The option -n prevents any completions already defined for the
command or context from being overwritten.
The option -d deletes any completion defined for the command or
contexts listed.
The names may also contain -p, -P and -N options as described for
the #compdef tag. The effect on the argument list is identical,
switching between definitions of patterns tried initially, pat-
terns tried finally, and normal commands and contexts.
The parameter $_compskip may be set by any function defined for a
pattern context. If it is set to a value containing the sub-
string `patterns' none of the pattern-functions will be called;
if it is set to a value containing the substring `all', no other
function will be called. Setting $_compskip in this manner is of
particular utility when using the -p option, as otherwise the
dispatcher will move on to additional functions (likely the de-
fault one) after calling the pattern-context one, which can man-
gle the display of completion possibilities if not handled prop-
erly.
The form with -k defines a widget with the same name as the func-
tion that will be called for each of the key-sequences; this is
like the #compdef -k tag. The function should generate the com-
pletions needed and will otherwise behave like the builtin widget
whose name is given as the style argument. The widgets usable
for this are: complete-word, delete-char-or-list, expand-or-com-
plete, expand-or-complete-prefix, list-choices, menu-complete,
menu-expand-or-complete, and reverse-menu-complete, as well as
menu-select if the zsh/complist module is loaded. The option -n
prevents the key being bound if it is already to bound to some-
thing other than undefined-key.
The form with -K is similar and defines multiple widgets based on
the same function, each of which requires the set of three argu-
ments name, style and key-sequence, where the latter two are as
for -k and the first must be a unique widget name beginning with
an underscore.
Wherever applicable, the -a option makes the function autoload-
able, equivalent to autoload -U function.
The function compdef can be used to associate existing completion func-
tions with new commands. For example,
compdef _pids foo
uses the function _pids to complete process IDs for the command foo.
Note also the _gnu_generic function described below, which can be used
to complete options for commands that understand the `--help' option.
COMPLETION SYSTEM CONFIGURATION
This section gives a short overview of how the completion system works,
and then more detail on how users can configure how and when matches are
generated.
Overview
When completion is attempted somewhere on the command line the comple-
tion system begins building the context. The context represents every-
thing that the shell knows about the meaning of the command line and the
significance of the cursor position. This takes account of a number of
things including the command word (such as `grep' or `zsh') and options
to which the current word may be an argument (such as the `-o' option to
zsh which takes a shell option as an argument).
The context starts out very generic ("we are beginning a completion")
and becomes more specific as more is learned ("the current word is in a
position that is usually a command name" or "the current word might be a
variable name" and so on). Therefore the context will vary during the
same call to the completion system.
This context information is condensed into a string consisting of multi-
ple fields separated by colons, referred to simply as `the context' in
the remainder of the documentation. Note that a user of the completion
system rarely needs to compose a context string, unless for example a
new function is being written to perform completion for a new command.
What a user may need to do is compose a style pattern, which is matched
against a context when needed to look up context-sensitive options that
configure the completion system.
The next few paragraphs explain how a context is composed within the
completion function suite. Following that is discussion of how styles
are defined. Styles determine such things as how the matches are gener-
ated, similarly to shell options but with much more control. They are
defined with the zstyle builtin command (see zshmodules(1)).
The context string always consists of a fixed set of fields, separated
by colons and with a leading colon before the first. Fields which are
not yet known are left empty, but the surrounding colons appear anyway.
The fields are always in the order :completion:function:completer:com-
mand:argument:tag. These have the following meaning:
• The literal string completion, saying that this style is used by
the completion system. This distinguishes the context from those
used by, for example, zle widgets and ZFTP functions.
• The function, if completion is called from a named widget rather
than through the normal completion system. Typically this is
blank, but it is set by special widgets such as predict-on and
the various functions in the Widget directory of the distribution
to the name of that function, often in an abbreviated form.
• The completer currently active, the name of the function without
the leading underscore and with other underscores converted to
hyphens. A `completer' is in overall control of how completion
is to be performed; `complete' is the simplest, but other com-
pleters exist to perform related tasks such as correction, or to
modify the behaviour of a later completer. See the section `Con-
trol Functions' below for more information.
• The command or a special -context-, just at it appears following
the #compdef tag or the compdef function. Completion functions
for commands that have sub-commands usually modify this field to
contain the name of the command followed by a minus sign and the
sub-command. For example, the completion function for the cvs
command sets this field to cvs-add when completing arguments to
the add subcommand.
• The argument; this indicates which command line or option argu-
ment we are completing. For command arguments this generally
takes the form argument-n, where n is the number of the argument,
and for arguments to options the form option-opt-n where n is the
number of the argument to option opt. However, this is only the
case if the command line is parsed with standard UNIX-style op-
tions and arguments, so many completions do not set this.
• The tag. As described previously, tags are used to discriminate
between the types of matches a completion function can generate
in a certain context. Any completion function may use any tag
name it likes, but a list of the more common ones is given below.
The context is gradually put together as the functions are executed,
starting with the main entry point, which adds :completion: and the
function element if necessary. The completer then adds the completer
element. The contextual completion adds the command and argument op-
tions. Finally, the tag is added when the types of completion are
known. For example, the context name
:completion::complete:dvips:option-o-1:files
says that normal completion was attempted as the first argument to the
option -o of the command dvips:
dvips -o ...
and the completion function will generate filenames.
Usually completion will be tried for all possible tags in an order given
by the completion function. However, this can be altered by using the
tag-order style. Completion is then restricted to the list of given
tags in the given order.
The _complete_help bindable command shows all the contexts and tags
available for completion at a particular point. This provides an easy
way of finding information for tag-order and other styles. It is de-
scribed in the section `Bindable Commands' below.
When looking up styles the completion system uses full context names,
including the tag. Looking up the value of a style therefore consists
of two things: the context, which is matched to the most specific (best
fitting) pattern, and the name of the style itself, which must be
matched exactly. The following examples demonstrate that patterns may
be loosely defined for styles that apply broadly, or as tightly defined
as desired for styles that apply in narrower circumstances.
For example, many completion functions can generate matches in a simple
and a verbose form and use the verbose style to decide which form should
be used. To make all such functions use the verbose form, put
zstyle ':completion:*' verbose yes
in a startup file (probably .zshrc). This gives the verbose style the
value yes in every context inside the completion system, unless that
context has a more specific definition. It is best to avoid giving the
pattern as `*' in case the style has some meaning outside the completion
system.
Many such general purpose styles can be configured simply by using the
compinstall function.
A more specific example of the use of the verbose style is by the com-
pletion for the kill builtin. If the style is set, the builtin lists
full job texts and process command lines; otherwise it shows the bare
job numbers and PIDs. To turn the style off for this use only:
zstyle ':completion:*:*:kill:*:*' verbose no
For even more control, the style can use one of the tags `jobs' or
`processes'. To turn off verbose display only for jobs:
zstyle ':completion:*:*:kill:*:jobs' verbose no
The -e option to zstyle even allows completion function code to appear
as the argument to a style; this requires some understanding of the in-
ternals of completion functions (see see zshcompwid(1))). For example,
zstyle -e ':completion:*' hosts 'reply=($myhosts)'
This forces the value of the hosts style to be read from the variable
myhosts each time a host name is needed; this is useful if the value of
myhosts can change dynamically. For another useful example, see the ex-
ample in the description of the file-list style below. This form can be
slow and should be avoided for commonly examined styles such as menu and
list-rows-first.
Note that the order in which styles are defined does not matter; the
style mechanism uses the most specific possible match for a particular
style to determine the set of values. Strings are preferred over pat-
terns (for example, `:completion::complete:::foo' is more specific than
`:completion::complete:::*'), and longer patterns are preferred over the
pattern `*'. See zmodules(1) for details.
Context patterns that use something other than a wildcard (*) to match
the middle parts of the context -- the completer, command, and argument
in :completion:function:completer:command:argument:tag -- should include
all six colons (:) explicitly. Without this, a pattern such as :comple-
tion:*:foo:* could match foo against a component other than the intended
one (for example, against completer when a match against command was in-
tended).
Style names like those of tags are arbitrary and depend on the comple-
tion function. However, the following two sections list some of the
most common tags and styles.
Standard Tags
Some of the following are only used when looking up particular styles
and do not refer to a type of match.
accounts
used to look up the users-hosts style
all-expansions
used by the _expand completer when adding the single string con-
taining all possible expansions
all-files
for the names of all files (as distinct from a particular subset,
see the globbed-files tag).
arguments
for arguments to a command
arrays for names of array parameters
association-keys
for keys of associative arrays; used when completing inside a
subscript to a parameter of this type
bookmarks
when completing bookmarks (e.g. for URLs and the zftp function
suite)
builtins
for names of builtin commands
characters
for single characters in arguments of commands such as stty.
Also used when completing character classes after an opening
bracket
colormapids
for X colormap ids
colors for color names
commands
for names of external commands. Also used by complex commands
such as cvs when completing names subcommands.
contexts
for contexts in arguments to the zstyle builtin command
corrections
used by the _approximate and _correct completers for possible
corrections
cursors
for cursor names used by X programs
default
used in some contexts to provide a way of supplying a default
when more specific tags are also valid. Note that this tag is
used when only the function field of the context name is set
descriptions
used when looking up the value of the format style to generate
descriptions for types of matches
devices
for names of device special files
directories
for names of directories -- local-directories is used instead
when completing arguments of cd and related builtin commands when
the cdpath array is set
directory-stack
for entries in the directory stack
displays
for X display names
domains
for network domains
email-plugin
for email addresses from the `_email-plugin' backend of
_email_addresses
expansions
used by the _expand completer for individual words (as opposed to
the complete set of expansions) resulting from the expansion of a
word on the command line
extensions
for X server extensions
file-descriptors
for numbers of open file descriptors
files the generic file-matching tag used by functions completing file-
names
fonts for X font names
fstypes
for file system types (e.g. for the mount command)
functions
names of functions -- normally shell functions, although certain
commands may understand other kinds of function
globbed-files
for filenames when the name has been generated by pattern match-
ing
groups for names of user groups
history-words
for words from the history
hosts for hostnames
indexes
for array indexes
interfaces
for network interfaces
jobs for jobs (as listed by the `jobs' builtin)
keymaps
for names of zsh keymaps
keysyms
for names of X keysyms
libraries
for names of system libraries
limits for system limits
local-directories
for names of directories that are subdirectories of the current
working directory when completing arguments of cd and related
builtin commands (compare path-directories) -- when the cdpath
array is unset, directories is used instead
mailboxes
for e-mail folders
manuals
for names of manual pages
maps for map names (e.g. NIS maps)
messages
used to look up the format style for messages
modifiers
for names of X modifiers
modules
for modules (e.g. zsh modules)
my-accounts
used to look up the users-hosts style
named-directories
for named directories (you wouldn't have guessed that, would
you?)
names for all kinds of names
newsgroups
for USENET groups
nicknames
for nicknames of NIS maps
options
for command options
original
used by the _approximate, _correct and _expand completers when
offering the original string as a match
other-accounts
used to look up the users-hosts style
packages
for packages (e.g. rpm or installed Debian packages)
parameters
for names of parameters
path-directories
for names of directories found by searching the cdpath array when
completing arguments of cd and related builtin commands (compare
local-directories)
paths used to look up the values of the expand, ambiguous and spe-
cial-dirs styles
pods for perl pods (documentation files)
ports for communication ports
prefixes
for prefixes (like those of a URL)
printers
for print queue names
processes
for process identifiers
processes-names
used to look up the command style when generating the names of
processes for killall
sequences
for sequences (e.g. mh sequences)
sessions
for sessions in the zftp function suite
signals
for signal names
strings
for strings (e.g. the replacement strings for the cd builtin com-
mand)
styles for styles used by the zstyle builtin command
suffixes
for filename extensions
tags for tags (e.g. rpm tags)
targets
for makefile targets
time-zones
for time zones (e.g. when setting the TZ parameter)
types for types of whatever (e.g. address types for the xhost command)
urls used to look up the urls and local styles when completing URLs
users for usernames
values for one of a set of values in certain lists
variant
used by _pick_variant to look up the command to run when deter-
mining what program is installed for a particular command name.
visuals
for X visuals
warnings
used to look up the format style for warnings
widgets
for zsh widget names
windows
for IDs of X windows
zsh-options
for shell options
Standard Styles
Note that the values of several of these styles represent boolean val-
ues. Any of the strings `true', `on', `yes', and `1' can be used for
the value `true' and any of the strings `false', `off', `no', and `0'
for the value `false'. The behavior for any other value is undefined
except where explicitly mentioned. The default value may be either
`true' or `false' if the style is not set.
Some of these styles are tested first for every possible tag correspond-
ing to a type of match, and if no style was found, for the default tag.
The most notable styles of this type are menu, list-colors and styles
controlling completion listing such as list-packed and last-prompt.
When tested for the default tag, only the function field of the context
will be set so that a style using the default tag will normally be de-
fined along the lines of:
zstyle ':completion:*:default' menu ...
accept-exact
This is tested for the default tag in addition to the tags valid
for the current context. If it is set to `true' and any of the
trial matches is the same as the string on the command line, this
match will immediately be accepted (even if it would otherwise be
considered ambiguous).
When completing pathnames (where the tag used is `paths') this
style accepts any number of patterns as the value in addition to
the boolean values. Pathnames matching one of these patterns
will be accepted immediately even if the command line contains
some more partially typed pathname components and these match no
file under the directory accepted.
This style is also used by the _expand completer to decide if
words beginning with a tilde or parameter expansion should be ex-
panded. For example, if there are parameters foo and foobar, the
string `$foo' will only be expanded if accept-exact is set to
`true'; otherwise the completion system will be allowed to com-
plete $foo to $foobar. If the style is set to `continue', _expand
will add the expansion as a match and the completion system will
also be allowed to continue.
accept-exact-dirs
This is used by filename completion. Unlike accept-exact it is a
boolean. By default, filename completion examines all components
of a path to see if there are completions of that component, even
if the component matches an existing directory. For example,
when completion after /usr/bin/, the function examines possible
completions to /usr.
When this style is `true', any prefix of a path that matches an
existing directory is accepted without any attempt to complete it
further. Hence, in the given example, the path /usr/bin/ is ac-
cepted immediately and completion tried in that directory.
This style is also useful when completing after directories that
magically appear when referenced, such as ZFS .zfs directories or
NetApp .snapshot directories. When the style is set the shell
does not check for the existence of the directory within the par-
ent directory.
If you wish to inhibit this behaviour entirely, set the path-com-
pletion style (see below) to `false'.
add-space
This style is used by the _expand completer. If it is `true'
(the default), a space will be inserted after all words resulting
from the expansion, or a slash in the case of directory names.
If the value is `file', the completer will only add a space to
names of existing files. Either a boolean `true' or the value
`file' may be combined with `subst', in which case the completer
will not add a space to words generated from the expansion of a
substitution of the form `$(...)' or `${...}'.
The _prefix completer uses this style as a simple boolean value
to decide if a space should be inserted before the suffix.
ambiguous
This applies when completing non-final components of filename
paths, in other words those with a trailing slash. If it is set,
the cursor is left after the first ambiguous component, even if
menu completion is in use. The style is always tested with the
paths tag.
assign-list
When completing after an equals sign that is being treated as an
assignment, the completion system normally completes only one
filename. In some cases the value may be a list of filenames
separated by colons, as with PATH and similar parameters. This
style can be set to a list of patterns matching the names of such
parameters.
The default is to complete lists when the word on the line al-
ready contains a colon.
auto-description
If set, this style's value will be used as the description for
options that are not described by the completion functions, but
that have exactly one argument. The sequence `%d' in the value
will be replaced by the description for this argument. Depending
on personal preferences, it may be useful to set this style to
something like `specify: %d'. Note that this may not work for
some commands.
avoid-completer
This is used by the _all_matches completer to decide if the
string consisting of all matches should be added to the list cur-
rently being generated. Its value is a list of names of com-
pleters. If any of these is the name of the completer that gen-
erated the matches in this completion, the string will not be
added.
The default value for this style is `_expand _old_list _correct
_approximate', i.e. it contains the completers for which a string
with all matches will almost never be wanted.
cache-path
This style defines the path where any cache files containing
dumped completion data are stored. It defaults to `$ZDOT-
DIR/.zcompcache', or `$HOME/.zcompcache' if $ZDOTDIR is not de-
fined. The completion cache will not be used unless the
use-cache style is set.
cache-policy
This style defines the function that will be used to determine
whether a cache needs rebuilding. See the section on the
_cache_invalid function below.
call-command
This style is used in the function for commands such as make and
ant where calling the command directly to generate matches suf-
fers problems such as being slow or, as in the case of make can
potentially cause actions in the makefile to be executed. If it
is set to `true' the command is called to generate matches. The
default value of this style is `false'.
command
In many places, completion functions need to call external com-
mands to generate the list of completions. This style can be
used to override the command that is called in some such cases.
The elements of the value are joined with spaces to form a com-
mand line to execute. The value can also start with a hyphen, in
which case the usual command will be added to the end; this is
most useful for putting `builtin' or `command' in front to make
sure the appropriate version of a command is called, for example
to avoid calling a shell function with the same name as an exter-
nal command.
As an example, the completion function for process IDs uses this
style with the processes tag to generate the IDs to complete and
the list of processes to display (if the verbose style is
`true'). The list produced by the command should look like the
output of the ps command. The first line is not displayed, but
is searched for the string `PID' (or `pid') to find the position
of the process IDs in the following lines. If the line does not
contain `PID', the first numbers in each of the other lines are
taken as the process IDs to complete.
Note that the completion function generally has to call the spec-
ified command for each attempt to generate the completion list.
Hence care should be taken to specify only commands that take a
short time to run, and in particular to avoid any that may never
terminate.
command-path
This is a list of directories to search for commands to complete.
The default for this style is the value of the special parameter
path.
commands
This is used by the function completing sub-commands for the sys-
tem initialisation scripts (residing in /etc/init.d or somewhere
not too far away from that). Its values give the default com-
mands to complete for those commands for which the completion
function isn't able to find them out automatically. The default
for this style are the two strings `start' and `stop'.
complete
This is used by the _expand_alias function when invoked as a
bindable command. If set to `true' and the word on the command
line is not the name of an alias, matching alias names will be
completed.
complete-options
This is used by the completer for cd, chdir and pushd. For these
commands a - is used to introduce a directory stack entry and
completion of these is far more common than completing options.
Hence unless the value of this style is `true' options will not
be completed, even after an initial -. If it is `true', options
will be completed after an initial - unless there is a preceding
-- on the command line.
completer
The strings given as the value of this style provide the names of
the completer functions to use. The available completer functions
are described in the section `Control Functions' below.
Each string may be either the name of a completer function or a
string of the form `function:name'. In the first case the com-
pleter field of the context will contain the name of the com-
pleter without the leading underscore and with all other under-
scores replaced by hyphens. In the second case the function is
the name of the completer to call, but the context will contain
the user-defined name in the completer field of the context. If
the name starts with a hyphen, the string for the context will be
build from the name of the completer function as in the first
case with the name appended to it. For example:
zstyle ':completion:*' completer _complete _complete:-foo
Here, completion will call the _complete completer twice, once
using `complete' and once using `complete-foo' in the completer
field of the context. Normally, using the same completer more
than once only makes sense when used with the `functions:name'
form, because otherwise the context name will be the same in all
calls to the completer; possible exceptions to this rule are the
_ignored and _prefix completers.
The default value for this style is `_complete _ignored': only
completion will be done, first using the ignored-patterns style
and the $fignore array and then without ignoring matches.
condition
This style is used by the _list completer function to decide if
insertion of matches should be delayed unconditionally. The de-
fault is `true'.
delimiters
This style is used when adding a delimiter for use with history
modifiers or glob qualifiers that have delimited arguments. It
is an array of preferred delimiters to add. Non-special charac-
ters are preferred as the completion system may otherwise become
confused. The default list is :, +, /, -, %. The list may be
empty to force a delimiter to be typed.
disabled
If this is set to `true', the _expand_alias completer and bind-
able command will try to expand disabled aliases, too. The de-
fault is `false'.
domains
A list of names of network domains for completion. If this is
not set, domain names will be taken from the file /etc/re-
solv.conf.
environ
The environ style is used when completing for `sudo'. It is set
to an array of `VAR=value' assignments to be exported into the
local environment before the completion for the target command is
invoked.
zstyle ':completion:*:sudo::' environ \
PATH="/sbin:/usr/sbin:$PATH" HOME="/root"
expand This style is used when completing strings consisting of multiple
parts, such as path names.
If one of its values is the string `prefix', the partially typed
word from the line will be expanded as far as possible even if
trailing parts cannot be completed.
If one of its values is the string `suffix', matching names for
components after the first ambiguous one will also be added.
This means that the resulting string is the longest unambiguous
string possible. However, menu completion can be used to cycle
through all matches.
extra-verbose
If set, the completion listing is more verbose at the cost of a
probable decrease in completion speed. Completion performance
will suffer if this style is set to `true'.
fake This style may be set for any completion context. It specifies
additional strings that will always be completed in that context.
The form of each string is `value:description'; the colon and de-
scription may be omitted, but any literal colons in value must be
quoted with a backslash. Any description provided is shown
alongside the value in completion listings.
It is important to use a sufficiently restrictive context when
specifying fake strings. Note that the styles fake-files and
fake-parameters provide additional features when completing files
or parameters.
fake-always
This works identically to the fake style except that the ig-
nored-patterns style is not applied to it. This makes it possi-
ble to override a set of matches completely by setting the ig-
nored patterns to `*'.
The following shows a way of supplementing any tag with arbitrary
data, but having it behave for display purposes like a separate
tag. In this example we use the features of the tag-order style
to divide the named-directories tag into two when performing com-
pletion with the standard completer complete for arguments of cd.
The tag named-directories-normal behaves as normal, but the tag
named-directories-mine contains a fixed set of directories. This
has the effect of adding the match group `extra directories' with
the given completions.
zstyle ':completion::complete:cd:*' tag-order \
'named-directories:-mine:extra\ directories
named-directories:-normal:named\ directories *'
zstyle ':completion::complete:cd:*:named-directories-mine' \
fake-always mydir1 mydir2
zstyle ':completion::complete:cd:*:named-directories-mine' \
ignored-patterns '*'
fake-files
This style is used when completing files and looked up without a
tag. Its values are of the form `dir:names...'. This will add
the names (strings separated by spaces) as possible matches when
completing in the directory dir, even if no such files really ex-
ist. The dir may be a pattern; pattern characters or colons in
dir should be quoted with a backslash to be treated literally.
This can be useful on systems that support special file systems
whose top-level pathnames can not be listed or generated with
glob patterns (but see accept-exact-dirs for a more general way
of dealing with this problem). It can also be used for directo-
ries for which one does not have read permission.
The pattern form can be used to add a certain `magic' entry to
all directories on a particular file system.
fake-parameters
This is used by the completion function for parameter names. Its
values are names of parameters that might not yet be set but
should be completed nonetheless. Each name may also be followed
by a colon and a string specifying the type of the parameter
(like `scalar', `array' or `integer'). If the type is given, the
name will only be completed if parameters of that type are re-
quired in the particular context. Names for which no type is
specified will always be completed.
file-list
This style controls whether files completed using the standard
builtin mechanism are to be listed with a long list similar to ls
-l. Note that this feature uses the shell module zsh/stat for
file information; this loads the builtin stat which will replace
any external stat executable. To avoid this the following code
can be included in an initialization file:
zmodload -i zsh/stat
disable stat
The style may either be set to a `true' value (or `all'), or one
of the values `insert' or `list', indicating that files are to be
listed in long format in all circumstances, or when attempting to
insert a file name, or when listing file names without attempting
to insert one.
More generally, the value may be an array of any of the above
values, optionally followed by =num. If num is present it gives
the maximum number of matches for which long listing style will
be used. For example,
zstyle ':completion:*' file-list list=20 insert=10
specifies that long format will be used when listing up to 20
files or inserting a file with up to 10 matches (assuming a list-
ing is to be shown at all, for example on an ambiguous comple-
tion), else short format will be used.
zstyle -e ':completion:*' file-list \
'(( ${+NUMERIC} )) && reply=(true)'
specifies that long format will be used any time a numeric argu-
ment is supplied, else short format.
file-patterns
This is used by the standard function for completing filenames,
_files. If the style is unset up to three tags are offered,
`globbed-files',`directories' and `all-files', depending on the
types of files expected by the caller of _files. The first two
(`globbed-files' and `directories') are normally offered together
to make it easier to complete files in sub-directories.
The file-patterns style provides alternatives to the default
tags, which are not used. Its value consists of elements of the
form `pattern:tag'; each string may contain any number of such
specifications separated by spaces.
The pattern is a pattern that is to be used to generate file-
names. Any occurrence of the sequence `%p' is replaced by any
pattern(s) passed by the function calling _files. Colons in the
pattern must be preceded by a backslash to make them distinguish-
able from the colon before the tag. If more than one pattern is
needed, the patterns can be given inside braces, separated by
commas.
The tags of all strings in the value will be offered by _files
and used when looking up other styles. Any tags in the same word
will be offered at the same time and before later words. If no
`:tag' is given the `files' tag will be used.
The tag may also be followed by an optional second colon and a
description, which will be used for the `%d' in the value of the
format style (if that is set) instead of the default description
supplied by the completion function. The inclusion of a descrip-
tion also gives precedence to associated options such as for com-
pletion grouping so it can be used where files should be sepa-
rated.
For example, to make the rm command first complete only names of
object files and then the names of all files if there is no
matching object file:
zstyle ':completion:*:*:rm:*:*' file-patterns \
'*.o:object-files' '%p:all-files'
To alter the default behaviour of file completion -- offer files
matching a pattern and directories on the first attempt, then all
files -- to offer only matching files on the first attempt, then
directories, and finally all files:
zstyle ':completion:*' file-patterns \
'%p:globbed-files' '*(-/):directories' '*:all-files'
This works even where there is no special pattern: _files matches
all files using the pattern `*' at the first step and stops when
it sees this pattern. Note also it will never try a pattern more
than once for a single completion attempt.
To separate directories into a separate group from the files but
still complete them at the first attempt, a description needs to
be given. Note that directories need to be explicitly excluded
from the globbed-files because `*' will match directories. For
grouping, it is also necessary to set the group-name style.
zstyle ':completion:*' file-patterns \
'%p(^-/):globbed-files *(-/):directories:location'
During the execution of completion functions, the EXTENDED_GLOB
option is in effect, so the characters `#', `~' and `^' have spe-
cial meanings in the patterns.
file-sort
The standard filename completion function uses this style without
a tag to determine in which order the names should be listed;
menu completion will cycle through them in the same order. The
possible values are: `size' to sort by the size of the file;
`links' to sort by the number of links to the file; `modifica-
tion' (or `time' or `date') to sort by the last modification
time; `access' to sort by the last access time; and `inode' (or
`change') to sort by the last inode change time. If the style is
set to any other value, or is unset, files will be sorted alpha-
betically by name. If the value contains the string `reverse',
sorting is done in the opposite order. If the value contains the
string `follow', timestamps are associated with the targets of
symbolic links; the default is to use the timestamps of the links
themselves.
file-split-chars
A set of characters that will cause all file completions for the
given context to be split at the point where any of the charac-
ters occurs. A typical use is to set the style to :; then every-
thing up to and including the last : in the string so far is ig-
nored when completing files. As this is quite heavy-handed, it
is usually preferable to update completion functions for contexts
where this behaviour is useful.
filter The ldap plugin of email address completion (see _email_ad-
dresses) uses this style to specify the attributes to match
against when filtering entries. So for example, if the style is
set to `sn', matching is done against surnames. Standard LDAP
filtering is used so normal completion matching is bypassed. If
this style is not set, the LDAP plugin is skipped. You may also
need to set the command style to specify how to connect to your
LDAP server.
force-list
This forces a list of completions to be shown at any point where
listing is done, even in cases where the list would usually be
suppressed. For example, normally the list is only shown if
there are at least two different matches. By setting this style
to `always', the list will always be shown, even if there is only
a single match that will immediately be accepted. The style may
also be set to a number. In this case the list will be shown if
there are at least that many matches, even if they would all in-
sert the same string.
This style is tested for the default tag as well as for each tag
valid for the current completion. Hence the listing can be
forced only for certain types of match.
format If this is set for the descriptions tag, its value is used as a
string to display above matches in completion lists. The se-
quence `%d' in this string will be replaced with a short descrip-
tion of what these matches are. This string may also contain the
output attribute sequences understood by compadd -X (see zshcomp-
wid(1)).
The style is tested with each tag valid for the current comple-
tion before it is tested for the descriptions tag. Hence differ-
ent format strings can be defined for different types of match.
Note also that some completer functions define additional `%'-se-
quences. These are described for the completer functions that
make use of them.
Some completion functions display messages that may be customised
by setting this style for the messages tag. Here, the `%d' is
replaced with a message given by the completion function.
Finally, the format string is looked up with the warnings tag,
for use when no matches could be generated at all. In this case
the `%d' is replaced with the descriptions for the matches that
were expected separated by spaces. The sequence `%D' is replaced
with the same descriptions separated by newlines.
It is possible to use printf-style field width specifiers with
`%d' and similar escape sequences. This is handled by the zfor-
mat builtin command from the zsh/zutil module, see zshmodules(1).
gain-privileges
If set to true, this style enables the use of commands like sudo
or doas to gain extra privileges when retrieving information for
completion. This is only done when a command such as sudo appears
on the command-line. To force the use of, e.g. sudo or to over-
ride any prefix that might be added due to gain-privileges, the
command style can be used with a value that begins with a hyphen.
glob This is used by the _expand completer. If it is set to `true'
(the default), globbing will be attempted on the words resulting
from a previous substitution (see the substitute style) or else
the original string from the line.
global If this is set to `true' (the default), the _expand_alias com-
pleter and bindable command will try to expand global aliases.
group-name
The completion system can group different types of matches, which
appear in separate lists. This style can be used to give the
names of groups for particular tags. For example, in command po-
sition the completion system generates names of builtin and ex-
ternal commands, names of aliases, shell functions and parameters
and reserved words as possible completions. To have the external
commands and shell functions listed separately:
zstyle ':completion:*:*:-command-:*:commands' \
group-name commands
zstyle ':completion:*:*:-command-:*:functions' \
group-name functions
As a consequence, any match with the same tag will be displayed
in the same group.
If the name given is the empty string the name of the tag for the
matches will be used as the name of the group. So, to have all
different types of matches displayed separately, one can just
set:
zstyle ':completion:*' group-name ''
All matches for which no group name is defined will be put in a
group named -default-.
To display the group name in the output, see the format style
(q.v.) under the descriptions tag.
group-order
This style is additional to the group-name style to specify the
order for display of the groups defined by that style (compare
tag-order, which determines which completions appear at all).
The groups named are shown in the given order; any other groups
are shown in the order defined by the completion function.
For example, to have names of builtin commands, shell functions
and external commands appear in that order when completing in
command position:
zstyle ':completion:*:*:-command-:*:*' group-order \
builtins functions commands
groups A list of names of UNIX groups. If this is not set, group names
are taken from the YP database or the file `/etc/group'.
hidden If this is set to `true', matches for the given context will not
be listed, although any description for the matches set with the
format style will be shown. If it is set to `all', not even the
description will be displayed.
Note that the matches will still be completed; they are just not
shown in the list. To avoid having matches considered as possi-
ble completions at all, the tag-order style can be modified as
described below.
hosts A list of names of hosts that should be completed. If this is
not set, hostnames are taken from the file `/etc/hosts'.
hosts-ports
This style is used by commands that need or accept hostnames and
network ports. The strings in the value should be of the form
`host:port'. Valid ports are determined by the presence of host-
names; multiple ports for the same host may appear.
ignore-line
This is tested for each tag valid for the current completion. If
it is set to `true', none of the words that are already on the
line will be considered as possible completions. If it is set to
`current', the word the cursor is on will not be considered as a
possible completion. The value `current-shown' is similar but
only applies if the list of completions is currently shown on the
screen. Finally, if the style is set to `other', all words on
the line except for the current one will be excluded from the
possible completions.
The values `current' and `current-shown' are a bit like the oppo-
site of the accept-exact style: only strings with missing char-
acters will be completed.
Note that you almost certainly don't want to set this to `true'
or `other' for a general context such as `:completion:*'. This
is because it would disallow completion of, for example, options
multiple times even if the command in question accepts the option
more than once.
ignore-parents
The style is tested without a tag by the function completing
pathnames in order to determine whether to ignore the names of
directories already mentioned in the current word, or the name of
the current working directory. The value must include one or
both of the following strings:
parent The name of any directory whose path is already contained
in the word on the line is ignored. For example, when
completing after foo/../, the directory foo will not be
considered a valid completion.
pwd The name of the current working directory will not be com-
pleted; hence, for example, completion after ../ will not
use the name of the current directory.
In addition, the value may include one or both of:
.. Ignore the specified directories only when the word on the
line contains the substring `../'.
directory
Ignore the specified directories only when names of direc-
tories are completed, not when completing names of files.
Excluded values act in a similar fashion to values of the ig-
nored-patterns style, so they can be restored to consideration by
the _ignored completer.
ignored-patterns
A list of patterns; any trial completion matching one of the pat-
terns will be excluded from consideration. The _ignored com-
pleter can appear in the list of completers to restore the ig-
nored matches. This is a more configurable version of the shell
parameter $fignore.
Note that the EXTENDED_GLOB option is set during the execution of
completion functions, so the characters `#', `~' and `^' have
special meanings in the patterns.
insert This style is used by the _all_matches completer to decide
whether to insert the list of all matches unconditionally instead
of adding the list as another match.
insert-ids
When completing process IDs, for example as arguments to the kill
and wait builtins the name of a command may be converted to the
appropriate process ID. A problem arises when the process name
typed is not unique. By default (or if this style is set explic-
itly to `menu') the name will be converted immediately to a set
of possible IDs, and menu completion will be started to cycle
through them.
If the value of the style is `single', the shell will wait until
the user has typed enough to make the command unique before con-
verting the name to an ID; attempts at completion will be unsuc-
cessful until that point. If the value is any other string, menu
completion will be started when the string typed by the user is
longer than the common prefix to the corresponding IDs.
insert-sections
This style is used with tags of the form `manuals.X' when com-
pleting names of manual pages. If set and the X in the tag name
matches the section number of the page being completed, the sec-
tion number is inserted along with the page name. For example,
given
zstyle ':completion:*:manuals.*' insert-sections true
man ssh_<TAB> may be completed to man 5 ssh_config.
The value may also be set to one of `prepend', or `suffix'.
`prepend' behaves the same as `true' as in the above example,
while `suffix' would complete man ssh_<TAB> as man ssh_config.5.
This is especially useful in conjunction with separate-sections,
as it ensures that the page requested of man corresponds to the
one displayed in the completion listing when there are multiple
pages with the same name (e.g., printf(1) and printf(3)).
The default for this style is `false'.
insert-tab
If this is set to `true', the completion system will insert a TAB
character (assuming that was used to start completion) instead of
performing completion when there is no non-blank character to the
left of the cursor. If it is set to `false', completion will be
done even there.
The value may also contain the substrings `pending' or `pend-
ing=val'. In this case, the typed character will be inserted in-
stead of starting completion when there is unprocessed input
pending. If a val is given, completion will not be done if there
are at least that many characters of unprocessed input. This is
often useful when pasting characters into a terminal. Note how-
ever, that it relies on the $PENDING special parameter from the
zsh/zle module being set properly which is not guaranteed on all
platforms.
The default value of this style is `true' except for completion
within vared builtin command where it is `false'.
insert-unambiguous
This is used by the _match and _approximate completers. These
completers are often used with menu completion since the word
typed may bear little resemblance to the final completion. How-
ever, if this style is `true', the completer will start menu com-
pletion only if it could find no unambiguous initial string at
least as long as the original string typed by the user.
In the case of the _approximate completer, the completer field in
the context will already have been set to one of correct-num or
approximate-num, where num is the number of errors that were ac-
cepted.
In the case of the _match completer, the style may also be set to
the string `pattern'. Then the pattern on the line is left un-
changed if it does not match unambiguously.
keep-prefix
This style is used by the _expand completer. If it is `true',
the completer will try to keep a prefix containing a tilde or pa-
rameter expansion. Hence, for example, the string `~/f*' would
be expanded to `~/foo' instead of `/home/user/foo'. If the style
is set to `changed' (the default), the prefix will only be left
unchanged if there were other changes between the expanded words
and the original word from the command line. Any other value
forces the prefix to be expanded unconditionally.
The behaviour of _expand when this style is `true' is to cause
_expand to give up when a single expansion with the restored pre-
fix is the same as the original; hence any remaining completers
may be called.
known-hosts-files
This style should contain a list of files to search for host
names and (if the use-ip style is set) IP addresses in a format
compatible with ssh known_hosts files. If it is not set, the
files /etc/ssh/ssh_known_hosts and ~/.ssh/known_hosts are used.
last-prompt
This is a more flexible form of the ALWAYS_LAST_PROMPT option.
If it is `true', the completion system will try to return the
cursor to the previous command line after displaying a completion
list. It is tested for all tags valid for the current comple-
tion, then the default tag. The cursor will be moved back to the
previous line if this style is `true' for all types of match.
Note that unlike the ALWAYS_LAST_PROMPT option this is indepen-
dent of the numeric argument.
list This style is used by the _history_complete_word bindable com-
mand. If it is set to `true' it has no effect. If it is set to
`false' matches will not be listed. This overrides the setting
of the options controlling listing behaviour, in particular
AUTO_LIST. The context always starts with `:completion:his-
tory-words'.
list-colors
If the zsh/complist module is loaded, this style can be used to
set color specifications. This mechanism replaces the use of the
ZLS_COLORS and ZLS_COLOURS parameters described in the section
`The zsh/complist Module' in zshmodules(1), but the syntax is the
same.
If this style is set for the default tag, the strings in the
value are taken as specifications that are to be used everywhere.
If it is set for other tags, the specifications are used only for
matches of the type described by the tag. For this to work best,
the group-name style must be set to an empty string.
In addition to setting styles for specific tags, it is also pos-
sible to use group names specified explicitly by the group-name
tag together with the `(group)' syntax allowed by the ZLS_COLORS
and ZLS_COLOURS parameters and simply using the default tag.
It is possible to use any color specifications already set up for
the GNU version of the ls command:
zstyle ':completion:*:default' list-colors \
${(s.:.)LS_COLORS}
The default colors are the same as for the GNU ls command and can
be obtained by setting the style to an empty string (i.e. '').
list-dirs-first
This is used by file completion and corresponds to a particular
setting of the file-patterns style. If set, the default directo-
ries to be completed are listed separately from and before com-
pletion for other files.
list-grouped
If this style is `true' (the default), the completion system will
try to make certain completion listings more compact by grouping
matches. For example, options for commands that have the same
description (shown when the verbose style is set to `true') will
appear as a single entry. However, menu selection can be used to
cycle through all the matches.
list-packed
This is tested for each tag valid in the current context as well
as the default tag. If it is set to `true', the corresponding
matches appear in listings as if the LIST_PACKED option were set.
If it is set to `false', they are listed normally.
list-prompt
If this style is set for the default tag, completion lists that
don't fit on the screen can be scrolled (see the description of
the zsh/complist module in zshmodules(1)). The value, if not the
empty string, will be displayed after every screenful and the
shell will prompt for a key press; if the style is set to the
empty string, a default prompt will be used.
The value may contain the escape sequences: `%l' or `%L', which
will be replaced by the number of the last line displayed and the
total number of lines; `%m' or `%M', the number of the last
match shown and the total number of matches; and `%p' and `%P',
`Top' when at the beginning of the list, `Bottom' when at the end
and the position shown as a percentage of the total length other-
wise. In each case the form with the uppercase letter will be
replaced by a string of fixed width, padded to the right with
spaces, while the lowercase form will be replaced by a variable
width string. As in other prompt strings, the escape sequences
`%S', `%s', `%B', `%b', `%U', `%u' for entering and leaving the
display modes standout, bold and underline, and `%F', `%f', `%K',
`%k' for changing the foreground background colour, are also
available, as is the form `%{...%}' for enclosing escape se-
quences which display with zero (or, with a numeric argument,
some other) width.
After deleting this prompt the variable LISTPROMPT should be un-
set for the removal to take effect.
list-rows-first
This style is tested in the same way as the list-packed style and
determines whether matches are to be listed in a rows-first fash-
ion as if the LIST_ROWS_FIRST option were set.
list-separator
The value of this style is used in completion listing to separate
the string to complete from a description when possible (e.g.
when completing options). It defaults to `--' (two hyphens).
list-suffixes
This style is used by the function that completes filenames. If
it is `true', and completion is attempted on a string containing
multiple partially typed pathname components, all ambiguous com-
ponents will be shown. Otherwise, completion stops at the first
ambiguous component.
local This is for use with functions that complete URLs for which the
corresponding files are available directly from the file system.
Its value should consist of three strings: a hostname, the path
to the default web pages for the server, and the directory name
used by a user placing web pages within their home area.
For example:
zstyle ':completion:*' local toast \
/var/http/public/toast public_html
Completion after `http://toast/stuff/' will look for files in the
directory /var/http/public/toast/stuff, while completion after
`http://toast/~yousir/' will look for files in the directory
~yousir/public_html.
mail-directory
If set, zsh will assume that mailbox files can be found in the
directory specified. It defaults to `~/Mail'.
match-original
This is used by the _match completer. If it is set to only,
_match will try to generate matches without inserting a `*' at
the cursor position. If set to any other non-empty value, it
will first try to generate matches without inserting the `*' and
if that yields no matches, it will try again with the `*' in-
serted. If it is unset or set to the empty string, matching will
only be performed with the `*' inserted.
matcher
This style is tested separately for each tag valid in the current
context. Its value is placed before any match specifications
given by the matcher-list style so can override them via the use
of an x: specification. The value should be in the form de-
scribed in the section `Completion Matching Control' in zshcomp-
wid(1). For examples of this, see the description of the tag-or-
der style.
For notes comparing the use of this and the matcher-list style,
see under the description of the tag-order style.
matcher-list
This style can be set to a list of match specifications that are
to be applied everywhere. Match specifications are described in
the section `Completion Matching Control' in zshcompwid(1). The
completion system will try them one after another for each com-
pleter selected. For example, to try first simple completion
and, if that generates no matches, case-insensitive completion:
zstyle ':completion:*' matcher-list '' 'm:{a-zA-Z}={A-Za-z}'
By default each specification replaces the previous one; however,
if a specification is prefixed with +, it is added to the exist-
ing list. Hence it is possible to create increasingly general
specifications without repetition:
zstyle ':completion:*' matcher-list \
'' '+m:{a-z}={A-Z}' '+m:{A-Z}={a-z}'
It is possible to create match specifications valid for particu-
lar completers by using the third field of the context. This ap-
plies only to completers that override the global matcher-list,
which as of this writing includes only _prefix and _ignored. For
example, to use the completers _complete and _prefix but allow
case-insensitive completion only with _complete:
zstyle ':completion:*' completer _complete _prefix
zstyle ':completion:*:complete:*:*:*' matcher-list \
'' 'm:{a-zA-Z}={A-Za-z}'
User-defined names, as explained for the completer style, are
available. This makes it possible to try the same completer more
than once with different match specifications each time. For ex-
ample, to try normal completion without a match specification,
then normal completion with case-insensitive matching, then cor-
rection, and finally partial-word completion:
zstyle ':completion:*' completer \
_complete _correct _complete:foo
zstyle ':completion:*:complete:*:*:*' matcher-list \
'' 'm:{a-zA-Z}={A-Za-z}'
zstyle ':completion:*:foo:*:*:*' matcher-list \
'm:{a-zA-Z}={A-Za-z} r:|[-_./]=* r:|=*'
If the style is unset in any context no match specification is
applied. Note also that some completers such as _correct and
_approximate do not use the match specifications at all, though
these completers will only ever be called once even if the
matcher-list contains more than one element.
Where multiple specifications are useful, note that the entire
completion is done for each element of matcher-list, which can
quickly reduce the shell's performance. As a rough rule of
thumb, one to three strings will give acceptable performance. On
the other hand, putting multiple space-separated values into the
same string does not have an appreciable impact on performance.
If there is no current matcher or it is empty, and the option
NO_CASE_GLOB is in effect, the matching for files is performed
case-insensitively in any case. However, any matcher must ex-
plicitly specify case-insensitive matching if that is required.
For notes comparing the use of this and the matcher style, see
under the description of the tag-order style.
max-errors
This is used by the _approximate and _correct completer functions
to determine the maximum number of errors to allow. The com-
pleter will try to generate completions by first allowing one er-
ror, then two errors, and so on, until either a match or matches
were found or the maximum number of errors given by this style
has been reached.
If the value for this style contains the string `numeric', the
completer function will take any numeric argument as the maximum
number of errors allowed. For example, with
zstyle ':completion:*:approximate:::' max-errors 2 numeric
two errors are allowed if no numeric argument is given, but with
a numeric argument of six (as in `ESC-6 TAB'), up to six errors
are accepted. Hence with a value of `0 numeric', no correcting
completion will be attempted unless a numeric argument is given.
If the value contains the string `not-numeric', the completer
will not try to generate corrected completions when given a nu-
meric argument, so in this case the number given should be
greater than zero. For example, `2 not-numeric' specifies that
correcting completion with two errors will usually be performed,
but if a numeric argument is given, correcting completion will
not be performed.
The default value for this style is `2 numeric'.
max-matches-width
This style is used to determine the trade off between the width
of the display used for matches and the width used for their de-
scriptions when the verbose style is in effect. The value gives
the number of display columns to reserve for the matches. The
default is half the width of the screen.
This has the most impact when several matches have the same de-
scription and so will be grouped together. Increasing the style
will allow more matches to be grouped together; decreasing it
will allow more of the description to be visible.
menu If this is `true' in the context of any of the tags defined for
the current completion menu completion will be used. The value
for a specific tag will take precedence over that for the `de-
fault' tag.
If none of the values found in this way is `true' but at least
one is set to `auto', the shell behaves as if the AUTO_MENU op-
tion is set.
If one of the values is explicitly set to `false', menu comple-
tion will be explicitly turned off, overriding the MENU_COMPLETE
option and other settings.
In the form `yes=num', where `yes' may be any of the `true' val-
ues (`yes', `true', `on' and `1'), menu completion will be turned
on if there are at least num matches. In the form `yes=long',
menu completion will be turned on if the list does not fit on the
screen. This does not activate menu completion if the widget
normally only lists completions, but menu completion can be acti-
vated in that case with the value `yes=long-list' (Typically, the
value `select=long-list' described later is more useful as it
provides control over scrolling.)
Similarly, with any of the `false' values (as in `no=10'), menu
completion will not be used if there are num or more matches.
The value of this widget also controls menu selection, as imple-
mented by the zsh/complist module. The following values may ap-
pear either alongside or instead of the values above.
If the value contains the string `select', menu selection will be
started unconditionally.
In the form `select=num', menu selection will only be started if
there are at least num matches. If the values for more than one
tag provide a number, the smallest number is taken.
Menu selection can be turned off explicitly by defining a value
containing the string`no-select'.
It is also possible to start menu selection only if the list of
matches does not fit on the screen by using the value `se-
lect=long'. To start menu selection even if the current widget
only performs listing, use the value `select=long-list'.
To turn on menu completion or menu selection when there are a
certain number of matches or the list of matches does not fit on
the screen, both of `yes=' and `select=' may be given twice, once
with a number and once with `long' or `long-list'.
Finally, it is possible to activate two special modes of menu se-
lection. The word `interactive' in the value causes interactive
mode to be entered immediately when menu selection is started;
see the description of the zsh/complist module in zshmodules(1)
for a description of interactive mode. Including the string
`search' does the same for incremental search mode. To select
backward incremental search, include the string `search-back-
ward'.
muttrc If set, gives the location of the mutt configuration file. It
defaults to `~/.muttrc'.
numbers
This is used with the jobs tag. If it is `true', the shell will
complete job numbers instead of the shortest unambiguous prefix
of the job command text. If the value is a number, job numbers
will only be used if that many words from the job descriptions
are required to resolve ambiguities. For example, if the value
is `1', strings will only be used if all jobs differ in the first
word on their command lines.
old-list
This is used by the _oldlist completer. If it is set to `al-
ways', then standard widgets which perform listing will retain
the current list of matches, however they were generated; this
can be turned off explicitly with the value `never', giving the
behaviour without the _oldlist completer. If the style is unset,
or any other value, then the existing list of completions is dis-
played if it is not already; otherwise, the standard completion
list is generated; this is the default behaviour of _oldlist.
However, if there is an old list and this style contains the name
of the completer function that generated the list, then the old
list will be used even if it was generated by a widget which does
not do listing.
For example, suppose you type ^Xc to use the _correct_word wid-
get, which generates a list of corrections for the word under the
cursor. Usually, typing ^D would generate a standard list of
completions for the word on the command line, and show that.
With _oldlist, it will instead show the list of corrections al-
ready generated.
As another example consider the _match completer: with the in-
sert-unambiguous style set to `true' it inserts only a common
prefix string, if there is any. However, this may remove parts
of the original pattern, so that further completion could produce
more matches than on the first attempt. By using the _oldlist
completer and setting this style to _match, the list of matches
generated on the first attempt will be used again.
old-matches
This is used by the _all_matches completer to decide if an old
list of matches should be used if one exists. This is selected
by one of the `true' values or by the string `only'. If the
value is `only', _all_matches will only use an old list and won't
have any effect on the list of matches currently being generated.
If this style is set it is generally unwise to call the
_all_matches completer unconditionally. One possible use is for
either this style or the completer style to be defined with the
-e option to zstyle to make the style conditional.
old-menu
This is used by the _oldlist completer. It controls how menu
completion behaves when a completion has already been inserted
and the user types a standard completion key such as TAB. The
default behaviour of _oldlist is that menu completion always con-
tinues with the existing list of completions. If this style is
set to `false', however, a new completion is started if the old
list was generated by a different completion command; this is the
behaviour without the _oldlist completer.
For example, suppose you type ^Xc to generate a list of correc-
tions, and menu completion is started in one of the usual ways.
Usually, or with this style set to `false', typing TAB at this
point would start trying to complete the line as it now appears.
With _oldlist, it instead continues to cycle through the list of
corrections.
original
This is used by the _approximate and _correct completers to de-
cide if the original string should be added as a possible comple-
tion. Normally, this is done only if there are at least two pos-
sible corrections, but if this style is set to `true', it is al-
ways added. Note that the style will be examined with the com-
pleter field in the context name set to correct-num or approxi-
mate-num, where num is the number of errors that were accepted.
packageset
This style is used when completing arguments of the Debian `dpkg'
program. It contains an override for the default package set for
a given context. For example,
zstyle ':completion:*:complete:dpkg:option--status-1:*' \
packageset avail
causes available packages, rather than only installed packages,
to be completed for `dpkg --status'.
path The function that completes color names uses this style with the
colors tag. The value should be the pathname of a file contain-
ing color names in the format of an X11 rgb.txt file. If the
style is not set but this file is found in one of various stan-
dard locations it will be used as the default.
path-completion
This is used by filename completion. By default, filename com-
pletion examines all components of a path to see if there are
completions of that component. For example, /u/b/z can be com-
pleted to /usr/bin/zsh. Explicitly setting this style to `false'
inhibits this behaviour for path components up to the / before
the cursor; this overrides the setting of accept-exact-dirs.
Even with the style set to `false', it is still possible to com-
plete multiple paths by setting the option COMPLETE_IN_WORD and
moving the cursor back to the first component in the path to be
completed. For example, /u/b/z can be completed to /usr/bin/zsh
if the cursor is after the /u.
pine-directory
If set, specifies the directory containing PINE mailbox files.
There is no default, since recursively searching this directory
is inconvenient for anyone who doesn't use PINE.
ports A list of Internet service names (network ports) to complete. If
this is not set, service names are taken from the file `/etc/ser-
vices'.
prefix-hidden
This is used for certain completions which share a common prefix,
for example command options beginning with dashes. If it is
`true', the prefix will not be shown in the list of matches.
The default value for this style is `false'.
prefix-needed
This style is also relevant for matches with a common prefix. If
it is set to `true' this common prefix must be typed by the user
to generate the matches.
The style is applicable to the options, signals, jobs, functions,
and parameters completion tags.
For command options, this means that the initial `-', `+', or
`--' must be typed explicitly before option names will be com-
pleted.
For signals, an initial `-' is required before signal names will
be completed.
For jobs, an initial `%' is required before job names will be
completed.
For function and parameter names, an initial `_' or `.' is re-
quired before function or parameter names starting with those
characters will be completed.
The default value for this style is `false' for function and pa-
rameter completions, and `true' otherwise.
preserve-prefix
This style is used when completing path names. Its value should
be a pattern matching an initial prefix of the word to complete
that should be left unchanged under all circumstances. For exam-
ple, on some Unices an initial `//' (double slash) has a special
meaning; setting this style to the string `//' will preserve it.
As another example, setting this style to `?:/' under Cygwin
would allow completion after `a:/...' and so on.
range This is used by the _history completer and the _history_com-
plete_word bindable command to decide which words should be com-
pleted.
If it is a single number, only the last N words from the history
will be completed.
If it is a range of the form `max:slice', the last slice words
will be completed; then if that yields no matches, the slice
words before those will be tried and so on. This process stops
either when at least one match has been found, or max words have
been tried.
The default is to complete all words from the history at once.
recursive-files
If this style is set, its value is an array of patterns to be
tested against `$PWD/': note the trailing slash, which allows di-
rectories in the pattern to be delimited unambiguously by includ-
ing slashes on both sides. If an ordinary file completion fails
and the word on the command line does not yet have a directory
part to its name, the style is retrieved using the same tag as
for the completion just attempted, then the elements tested
against $PWD/ in turn. If one matches, then the shell reattempts
completion by prepending the word on the command line with each
directory in the expansion of **/*(/) in turn. Typically the el-
ements of the style will be set to restrict the number of direc-
tories beneath the current one to a manageable number, for exam-
ple `*/.git/*'.
For example,
zstyle ':completion:*' recursive-files '*/zsh/*'
If the current directory is /home/pws/zsh/Src, then zle_tr<TAB>
can be completed to Zle/zle_tricky.c.
regular
This style is used by the _expand_alias completer and bindable
command. If set to `true' (the default), regular aliases will be
expanded but only in command position. If it is set to `false',
regular aliases will never be expanded. If it is set to `al-
ways', regular aliases will be expanded even if not in command
position.
rehash If this is set when completing external commands, the internal
list (hash) of commands will be updated for each search by issu-
ing the rehash command. There is a speed penalty for this which
is only likely to be noticeable when directories in the path have
slow file access.
remote-access
If set to `false', certain commands will be prevented from making
Internet connections to retrieve remote information. This in-
cludes the completion for the CVS command.
It is not always possible to know if connections are in fact to a
remote site, so some may be prevented unnecessarily.
remove-all-dups
The _history_complete_word bindable command and the _history com-
pleter use this to decide if all duplicate matches should be re-
moved, rather than just consecutive duplicates.
select-prompt
If this is set for the default tag, its value will be displayed
during menu selection (see the menu style above) when the comple-
tion list does not fit on the screen as a whole. The same es-
capes as for the list-prompt style are understood, except that
the numbers refer to the match or line the mark is on. A default
prompt is used when the value is the empty string.
select-scroll
This style is tested for the default tag and determines how a
completion list is scrolled during a menu selection (see the menu
style above) when the completion list does not fit on the screen
as a whole. If the value is `0' (zero), the list is scrolled by
half-screenfuls; if it is a positive integer, the list is
scrolled by the given number of lines; if it is a negative num-
ber, the list is scrolled by a screenful minus the absolute value
of the given number of lines. The default is to scroll by single
lines.
separate-sections
This style is used with the manuals tag when completing names of
manual pages. If it is `true', entries for different sections
are added separately using tag names of the form `manuals.X',
where X is the section number. When the group-name style is also
in effect, pages from different sections will appear separately.
This style is also used similarly with the words style when com-
pleting words for the dict command. It allows words from differ-
ent dictionary databases to be added separately. See also in-
sert-sections.
The default for this style is `false'.
show-ambiguity
If the zsh/complist module is loaded, this style can be used to
highlight the first ambiguous character in completion lists. The
value is either a color indication such as those supported by the
list-colors style or, with a value of `true', a default of under-
lining is selected. The highlighting is only applied if the com-
pletion display strings correspond to the actual matches.
show-completer
Tested whenever a new completer is tried. If it is `true', the
completion system outputs a progress message in the listing area
showing what completer is being tried. The message will be over-
written by any output when completions are found and is removed
after completion is finished.
single-ignored
This is used by the _ignored completer when there is only one
match. If its value is `show', the single match will be dis-
played but not inserted. If the value is `menu', then the single
match and the original string are both added as matches and menu
completion is started, making it easy to select either of them.
sort This allows the standard ordering of matches to be overridden.
If its value is `true' or `false', sorting is enabled or dis-
abled. Additionally the values associated with the `-o' option
to compadd can also be listed: match, nosort, numeric, reverse.
If it is not set for the context, the standard behaviour of the
calling widget is used.
The style is tested first against the full context including the
tag, and if that fails to produce a value against the context
without the tag.
In many cases where a calling widget explicitly selects a partic-
ular ordering in lieu of the default, a value of `true' is not
honoured. An example of where this is not the case is for com-
mand history where the default of sorting matches chronologically
may be overridden by setting the style to `true'.
In the _expand completer, if it is set to `true', the expansions
generated will always be sorted. If it is set to `menu', then
the expansions are only sorted when they are offered as single
strings but not in the string containing all possible expansions.
special-dirs
Normally, the completion code will not produce the directory
names `.' and `..' as possible completions. If this style is set
to `true', it will add both `.' and `..' as possible completions;
if it is set to `..', only `..' will be added.
The following example sets special-dirs to `..' when the current
prefix is empty, is a single `.', or consists only of a path be-
ginning with `../'. Otherwise the value is `false'.
zstyle -e ':completion:*' special-dirs \
'[[ $PREFIX = (../)#(|.|..) ]] && reply=(..)'
squeeze-slashes
If set to `true', sequences of slashes in filename paths (for ex-
ample in `foo//bar') will be treated as a single slash. This is
the usual behaviour of UNIX paths. However, by default the file
completion function behaves as if there were a `*' between the
slashes.
stop If set to `true', the _history_complete_word bindable command
will stop once when reaching the beginning or end of the history.
Invoking _history_complete_word will then wrap around to the op-
posite end of the history. If this style is set to `false' (the
default), _history_complete_word will loop immediately as in a
menu completion.
strip-comments
If set to `true', this style causes non-essential comment text to
be removed from completion matches. Currently it is only used
when completing e-mail addresses where it removes any display
name from the addresses, cutting them down to plain user@host
form.
subst-globs-only
This is used by the _expand completer. If it is set to `true',
the expansion will only be used if it resulted from globbing;
hence, if expansions resulted from the use of the substitute
style described below, but these were not further changed by
globbing, the expansions will be rejected.
The default for this style is `false'.
substitute
This boolean style controls whether the _expand completer will
first try to expand all substitutions in the string (such as
`$(...)' and `${...}').
The default is `true'.
suffix This is used by the _expand completer if the word starts with a
tilde or contains a parameter expansion. If it is set to `true',
the word will only be expanded if it doesn't have a suffix, i.e.
if it is something like `~foo' or `$foo' rather than `~foo/' or
`$foo/bar', unless that suffix itself contains characters eligi-
ble for expansion. The default for this style is `true'.
tag-order
This provides a mechanism for sorting how the tags available in a
particular context will be used.
The values for the style are sets of space-separated lists of
tags. The tags in each value will be tried at the same time; if
no match is found, the next value is used. (See the file-pat-
terns style for an exception to this behavior.)
For example:
zstyle ':completion:*:complete:-command-:*:*' tag-order \
'commands functions'
specifies that completion in command position first offers exter-
nal commands and shell functions. Remaining tags will be tried
if no completions are found.
In addition to tag names, each string in the value may take one
of the following forms:
- If any value consists of only a hyphen, then only the tags
specified in the other values are generated. Normally all
tags not explicitly selected are tried last if the speci-
fied tags fail to generate any matches. This means that a
single value consisting only of a single hyphen turns off
completion.
! tags...
A string starting with an exclamation mark specifies names
of tags that are not to be used. The effect is the same
as if all other possible tags for the context had been
listed.
tag:label ...
Here, tag is one of the standard tags and label is an ar-
bitrary name. Matches are generated as normal but the
name label is used in contexts instead of tag. This is
not useful in words starting with !.
If the label starts with a hyphen, the tag is prepended to
the label to form the name used for lookup. This can be
used to make the completion system try a certain tag more
than once, supplying different style settings for each at-
tempt; see below for an example.
tag:label:description
As before, but description will replace the `%d' in the
value of the format style instead of the default descrip-
tion supplied by the completion function. Spaces in the
description must be quoted with a backslash. A `%d' ap-
pearing in description is replaced with the description
given by the completion function.
In any of the forms above the tag may be a pattern or several
patterns in the form `{pat1,pat2...}'. In this case all matching
tags will be used except for any given explicitly in the same
string.
One use of these features is to try one tag more than once, set-
ting other styles differently on each attempt, but still to use
all the other tags without having to repeat them all. For exam-
ple, to make completion of function names in command position ig-
nore all the completion functions starting with an underscore the
first time completion is tried:
zstyle ':completion:*:*:-command-:*:*' tag-order \
'functions:-non-comp *' functions
zstyle ':completion:*:functions-non-comp' \
ignored-patterns '_*'
On the first attempt, all tags will be offered but the functions
tag will be replaced by functions-non-comp. The ignored-patterns
style is set for this tag to exclude functions starting with an
underscore. If there are no matches, the second value of the
tag-order style is used which completes functions using the de-
fault tag, this time presumably including all function names.
The matches for one tag can be split into different groups. For
example:
zstyle ':completion:*' tag-order \
'options:-long:long\ options
options:-short:short\ options
options:-single-letter:single\ letter\ options'
zstyle ':completion:*:options-long' \
ignored-patterns '[-+](|-|[^-]*)'
zstyle ':completion:*:options-short' \
ignored-patterns '--*' '[-+]?'
zstyle ':completion:*:options-single-letter' \
ignored-patterns '???*'
With the group-names style set, options beginning with `--', op-
tions beginning with a single `-' or `+' but containing multiple
characters, and single-letter options will be displayed in sepa-
rate groups with different descriptions.
Another use of patterns is to try multiple match specifications
one after another. The matcher-list style offers something simi-
lar, but it is tested very early in the completion system and
hence can't be set for single commands nor for more specific con-
texts. Here is how to try normal completion without any match
specification and, if that generates no matches, try again with
case-insensitive matching, restricting the effect to arguments of
the command foo:
zstyle ':completion:*:*:foo:*:*' tag-order '*' '*:-case'
zstyle ':completion:*-case' matcher 'm:{a-z}={A-Z}'
First, all the tags offered when completing after foo are tried
using the normal tag name. If that generates no matches, the
second value of tag-order is used, which tries all tags again ex-
cept that this time each has -case appended to its name for
lookup of styles. Hence this time the value for the matcher
style from the second call to zstyle in the example is used to
make completion case-insensitive.
It is possible to use the -e option of the zstyle builtin command
to specify conditions for the use of particular tags. For exam-
ple:
zstyle -e '*:-command-:*' tag-order '
if [[ -n $PREFIX$SUFFIX ]]; then
reply=( )
else
reply=( - )
fi'
Completion in command position will be attempted only if the
string typed so far is not empty. This is tested using the PRE-
FIX special parameter; see zshcompwid for a description of para-
meters which are special inside completion widgets. Setting re-
ply to an empty array provides the default behaviour of trying
all tags at once; setting it to an array containing only a hyphen
disables the use of all tags and hence of all completions.
If no tag-order style has been defined for a context, the strings
`(|*-)argument-* (|*-)option-* values' and `options' plus all
tags offered by the completion function will be used to provide a
sensible default behavior that causes arguments (whether normal
command arguments or arguments of options) to be completed before
option names for most commands.
urls This is used together with the urls tag by functions completing
URLs.
If the value consists of more than one string, or if the only
string does not name a file or directory, the strings are used as
the URLs to complete.
If the value contains only one string which is the name of a nor-
mal file the URLs are taken from that file (where the URLs may be
separated by white space or newlines).
Finally, if the only string in the value names a directory, the
directory hierarchy rooted at this directory gives the comple-
tions. The top level directory should be the file access method,
such as `http', `ftp', `bookmark' and so on. In many cases the
next level of directories will be a filename. The directory hi-
erarchy can descend as deep as necessary.
For example,
zstyle ':completion:*' urls ~/.urls
mkdir -p ~/.urls/ftp/ftp.zsh.org/pub
allows completion of all the components of the URL
ftp://ftp.zsh.org/pub after suitable commands such as `netscape'
or `lynx'. Note, however, that access methods and files are com-
pleted separately, so if the hosts style is set hosts can be com-
pleted without reference to the urls style.
See the description in the function _urls itself for more infor-
mation (e.g. `more $^fpath/_urls(N)').
use-cache
If this is set, the completion caching layer is activated for any
completions which use it (via the _store_cache, _retrieve_cache,
and _cache_invalid functions). The directory containing the
cache files can be changed with the cache-path style.
use-compctl
If this style is set to a string not equal to false, 0, no, and
off, the completion system may use any completion specifications
defined with the compctl builtin command. If the style is unset,
this is done only if the zsh/compctl module is loaded. The
string may also contain the substring `first' to use completions
defined with `compctl -T', and the substring `default' to use the
completion defined with `compctl -D'.
Note that this is only intended to smooth the transition from
compctl to the new completion system and may disappear in the fu-
ture.
Note also that the definitions from compctl will only be used if
there is no specific completion function for the command in ques-
tion. For example, if there is a function _foo to complete argu-
ments to the command foo, compctl will never be invoked for foo.
However, the compctl version will be tried if foo only uses de-
fault completion.
use-ip By default, the function _hosts that completes host names strips
IP addresses from entries read from host databases such as NIS
and ssh files. If this style is `true', the corresponding IP ad-
dresses can be completed as well. This style is not use in any
context where the hosts style is set; note also it must be set
before the cache of host names is generated (typically the first
completion attempt).
users This may be set to a list of usernames to be completed. If it is
not set all usernames will be completed. Note that if it is set
only that list of users will be completed; this is because on
some systems querying all users can take a prohibitive amount of
time.
users-hosts
The values of this style should be of the form `user@host' or
`user:host'. It is used for commands that need pairs of user- and
hostnames. These commands will complete usernames from this
style (only), and will restrict subsequent hostname completion to
hosts paired with that user in one of the values of the style.
It is possible to group values for sets of commands which allow a
remote login, such as rlogin and ssh, by using the my-accounts
tag. Similarly, values for sets of commands which usually refer
to the accounts of other people, such as talk and finger, can be
grouped by using the other-accounts tag. More ambivalent com-
mands may use the accounts tag.
users-hosts-ports
Like users-hosts but used for commands like telnet and containing
strings of the form `user@host:port'.
verbose
If set, as it is by default, the completion listing is more ver-
bose. In particular many commands show descriptions for options
if this style is `true'.
word This is used by the _list completer, which prevents the insertion
of completions until a second completion attempt when the line
has not changed. The normal way of finding out if the line has
changed is to compare its entire contents between the two occa-
sions. If this style is `true', the comparison is instead per-
formed only on the current word. Hence if completion is per-
formed on another word with the same contents, completion will
not be delayed.
CONTROL FUNCTIONS
The initialization script compinit redefines all the widgets which per-
form completion to call the supplied widget function _main_complete.
This function acts as a wrapper calling the so-called `completer' func-
tions that generate matches. If _main_complete is called with argu-
ments, these are taken as the names of completer functions to be called
in the order given. If no arguments are given, the set of functions to
try is taken from the completer style. For example, to use normal com-
pletion and correction if that doesn't generate any matches:
zstyle ':completion:*' completer _complete _correct
after calling compinit. The default value for this style is `_complete
_ignored', i.e. normally only ordinary completion is tried, first with
the effect of the ignored-patterns style and then without it. The
_main_complete function uses the return status of the completer func-
tions to decide if other completers should be called. If the return
status is zero, no other completers are tried and the _main_complete
function returns.
If the first argument to _main_complete is a single hyphen, the argu-
ments will not be taken as names of completers. Instead, the second ar-
gument gives a name to use in the completer field of the context and the
other arguments give a command name and arguments to call to generate
the matches.
The following completer functions are contained in the distribution, al-
though users may write their own. Note that in contexts the leading un-
derscore is stripped, for example basic completion is performed in the
context `:completion::complete:...'.
_all_matches
This completer can be used to add a string consisting of all
other matches. As it influences later completers it must appear
as the first completer in the list. The list of all matches is
affected by the avoid-completer and old-matches styles described
above.
It may be useful to use the _generic function described below to
bind _all_matches to its own keystroke, for example:
zle -C all-matches complete-word _generic
bindkey '^Xa' all-matches
zstyle ':completion:all-matches:*' old-matches only
zstyle ':completion:all-matches::::' completer _all_matches
Note that this does not generate completions by itself: first
use any of the standard ways of generating a list of completions,
then use ^Xa to show all matches. It is possible instead to add
a standard completer to the list and request that the list of all
matches should be directly inserted:
zstyle ':completion:all-matches::::' completer \
_all_matches _complete
zstyle ':completion:all-matches:*' insert true
In this case the old-matches style should not be set.
_approximate
This is similar to the basic _complete completer but allows the
completions to undergo corrections. The maximum number of errors
can be specified by the max-errors style; see the description of
approximate matching in zshexpn(1) for how errors are counted.
Normally this completer will only be tried after the normal _com-
plete completer:
zstyle ':completion:*' completer _complete _approximate
This will give correcting completion if and only if normal com-
pletion yields no possible completions. When corrected comple-
tions are found, the completer will normally start menu comple-
tion allowing you to cycle through these strings.
This completer uses the tags corrections and original when gener-
ating the possible corrections and the original string. The for-
mat style for the former may contain the additional sequences
`%e' and `%o' which will be replaced by the number of errors ac-
cepted to generate the corrections and the original string, re-
spectively.
The completer progressively increases the number of errors al-
lowed up to the limit by the max-errors style, hence if a comple-
tion is found with one error, no completions with two errors will
be shown, and so on. It modifies the completer name in the con-
text to indicate the number of errors being tried: on the first
try the completer field contains `approximate-1', on the second
try `approximate-2', and so on.
When _approximate is called from another function, the number of
errors to accept may be passed with the -a option. The argument
is in the same format as the max-errors style, all in one string.
Note that this completer (and the _correct completer mentioned
below) can be quite expensive to call, especially when a large
number of errors are allowed. One way to avoid this is to set up
the completer style using the -e option to zstyle so that some
completers are only used when completion is attempted a second
time on the same string, e.g.:
zstyle -e ':completion:*' completer '
if [[ $_last_try != "$HISTNO$BUFFER$CURSOR" ]]; then
_last_try="$HISTNO$BUFFER$CURSOR"
reply=(_complete _match _prefix)
else
reply=(_ignored _correct _approximate)
fi'
This uses the HISTNO parameter and the BUFFER and CURSOR special
parameters that are available inside zle and completion widgets
to find out if the command line hasn't changed since the last
time completion was tried. Only then are the _ignored, _correct
and _approximate completers called.
_canonical_paths [ -A var ] [ -N ] [ -MJV12nfX ] tag descr [ paths ... ]
This completion function completes all paths given to it, and
also tries to offer completions which point to the same file as
one of the paths given (relative path when an absolute path is
given, and vice versa; when ..'s are present in the word to be
completed; and some paths got from symlinks).
-A, if specified, takes the paths from the array variable speci-
fied. Paths can also be specified on the command line as shown
above. -N, if specified, prevents canonicalizing the paths given
before using them for completion, in case they are already so.
The options -M, -J, -V, -1, -2, -n, -F, -X are passed to compadd.
See _description for a description of tag and descr.
_cmdambivalent
Completes the remaining positional arguments as an external com-
mand. The external command and its arguments are completed as
separate arguments (in a manner appropriate for completing
/usr/bin/env) if there are two or more remaining positional argu-
ments on the command line, and as a quoted command string (in the
manner of system(...)) otherwise. See also _cmdstring and _pre-
command.
This function takes no arguments.
_cmdstring
Completes an external command as a single argument, as for sys-
tem(...).
_complete
This completer generates all possible completions in a con-
text-sensitive manner, i.e. using the settings defined with the
compdef function explained above and the current settings of all
special parameters. This gives the normal completion behaviour.
To complete arguments of commands, _complete uses the utility
function _normal, which is in turn responsible for finding the
particular function; it is described below. Various contexts of
the form -context- are handled specifically. These are all men-
tioned above as possible arguments to the #compdef tag.
Before trying to find a function for a specific context, _com-
plete checks if the parameter `compcontext' is set. Setting `com-
pcontext' allows the usual completion dispatching to be overrid-
den which is useful in places such as a function that uses vared
for input. If it is set to an array, the elements are taken to be
the possible matches which will be completed using the tag `val-
ues' and the description `value'. If it is set to an associative
array, the keys are used as the possible completions and the val-
ues (if non-empty) are used as descriptions for the matches. If
`compcontext' is set to a string containing colons, it should be
of the form `tag:descr:action'. In this case the tag and descr
give the tag and description to use and the action indicates what
should be completed in one of the forms accepted by the _argu-
ments utility function described below.
Finally, if `compcontext' is set to a string without colons, the
value is taken as the name of the context to use and the function
defined for that context will be called. For this purpose, there
is a special context named -command-line- that completes whole
command lines (commands and their arguments). This is not used
by the completion system itself but is nonetheless handled when
explicitly called.
_correct
Generate corrections, but not completions, for the current word;
this is similar to _approximate but will not allow any number of
extra characters at the cursor as that completer does. The ef-
fect is similar to spell-checking. It is based on _approximate,
but the completer field in the context name is correct.
For example, with:
zstyle ':completion:::::' completer \
_complete _correct _approximate
zstyle ':completion:*:correct:::' max-errors 2 not-numeric
zstyle ':completion:*:approximate:::' max-errors 3 numeric
correction will accept up to two errors. If a numeric argument
is given, correction will not be performed, but correcting com-
pletion will be, and will accept as many errors as given by the
numeric argument. Without a numeric argument, first correction
and then correcting completion will be tried, with the first one
accepting two errors and the second one accepting three errors.
When _correct is called as a function, the number of errors to
accept may be given following the -a option. The argument is in
the same form a values to the accept style, all in one string.
This completer function is intended to be used without the _ap-
proximate completer or, as in the example, just before it. Using
it after the _approximate completer is useless since _approximate
will at least generate the corrected strings generated by the
_correct completer -- and probably more.
_expand
This completer function does not really perform completion, but
instead checks if the word on the command line is eligible for
expansion and, if it is, gives detailed control over how this ex-
pansion is done. For this to happen, the completion system needs
to be invoked with complete-word, not expand-or-complete (the de-
fault binding for TAB), as otherwise the string will be expanded
by the shell's internal mechanism before the completion system is
started. Note also this completer should be called before the
_complete completer function.
The tags used when generating expansions are all-expansions for
the string containing all possible expansions, expansions when
adding the possible expansions as single matches and original
when adding the original string from the line. The order in
which these strings are generated, if at all, can be controlled
by the group-order and tag-order styles, as usual.
The format string for all-expansions and for expansions may con-
tain the sequence `%o' which will be replaced by the original
string from the line.
The kind of expansion to be tried is controlled by the substi-
tute, glob and subst-globs-only styles.
It is also possible to call _expand as a function, in which case
the different modes may be selected with options: -s for substi-
tute, -g for glob and -o for subst-globs-only.
_expand_alias
If the word the cursor is on is an alias, it is expanded and no
other completers are called. The types of aliases which are to
be expanded can be controlled with the styles regular, global and
disabled.
This function is also a bindable command, see the section `Bind-
able Commands' below.
_extensions
If the cursor follows the string `*.', filename extensions are
completed. The extensions are taken from files in current direc-
tory or a directory specified at the beginning of the current
word. For exact matches, completion continues to allow other com-
pleters such as _expand to expand the pattern. The standard
add-space and prefix-hidden styles are observed.
_external_pwds
Completes current directories of other zsh processes belonging to
the current user.
This is intended to be used via _generic, bound to a custom key
combination. Note that pattern matching is enabled so matching is
performed similar to how it works with the _match completer.
_history
Complete words from the shell's command history. This completer
can be controlled by the remove-all-dups, and sort styles as for
the _history_complete_word bindable command, see the section
`Bindable Commands' below and the section `Completion System Con-
figuration' above.
_ignored
The ignored-patterns style can be set to a list of patterns which
are compared against possible completions; matching ones are re-
moved. With this completer those matches can be reinstated, as
if no ignored-patterns style were set. The completer actually
generates its own list of matches; which completers are invoked
is determined in the same way as for the _prefix completer. The
single-ignored style is also available as described above.
_list This completer allows the insertion of matches to be delayed un-
til completion is attempted a second time without the word on the
line being changed. On the first attempt, only the list of
matches will be shown. It is affected by the styles condition
and word, see the section `Completion System Configuration'
above.
_match This completer is intended to be used after the _complete com-
pleter. It behaves similarly but the string on the command line
may be a pattern to match against trial completions. This gives
the effect of the GLOB_COMPLETE option.
Normally completion will be performed by taking the pattern from
the line, inserting a `*' at the cursor position and comparing
the resulting pattern with the possible completions generated.
This can be modified with the match-original style described
above.
The generated matches will be offered in a menu completion unless
the insert-unambiguous style is set to `true'; see the descrip-
tion above for other options for this style.
Note that matcher specifications defined globally or used by the
completion functions (the styles matcher-list and matcher) will
not be used.
_menu This completer was written as simple example function to show how
menu completion can be enabled in shell code. However, it has the
notable effect of disabling menu selection which can be useful
with _generic based widgets. It should be used as the first com-
pleter in the list. Note that this is independent of the setting
of the MENU_COMPLETE option and does not work with the other menu
completion widgets such as reverse-menu-complete, or ac-
cept-and-menu-complete.
_oldlist
This completer controls how the standard completion widgets be-
have when there is an existing list of completions which may have
been generated by a special completion (i.e. a separately-bound
completion command). It allows the ordinary completion keys to
continue to use the list of completions thus generated, instead
of producing a new list of ordinary contextual completions. It
should appear in the list of completers before any of the widgets
which generate matches. It uses two styles: old-list and
old-menu, see the section `Completion System Configuration'
above.
_precommand
Complete an external command in word-separated arguments, as for
exec and /usr/bin/env.
_prefix
This completer can be used to try completion with the suffix
(everything after the cursor) ignored. In other words, the suf-
fix will not be considered to be part of the word to complete.
The effect is similar to the expand-or-complete-prefix command.
The completer style is used to decide which other completers are
to be called to generate matches. If this style is unset, the
list of completers set for the current context is used -- except,
of course, the _prefix completer itself. Furthermore, if this
completer appears more than once in the list of completers only
those completers not already tried by the last invocation of
_prefix will be called.
For example, consider this global completer style:
zstyle ':completion:*' completer \
_complete _prefix _correct _prefix:foo
Here, the _prefix completer tries normal completion but ignoring
the suffix. If that doesn't generate any matches, and neither
does the call to the _correct completer after it, _prefix will be
called a second time and, now only trying correction with the
suffix ignored. On the second invocation the completer part of
the context appears as `foo'.
To use _prefix as the last resort and try only normal completion
when it is invoked:
zstyle ':completion:*' completer _complete ... _prefix
zstyle ':completion::prefix:*' completer _complete
The add-space style is also respected. If it is set to `true'
then _prefix will insert a space between the matches generated
(if any) and the suffix.
Note that this completer is only useful if the COMPLETE_IN_WORD
option is set; otherwise, the cursor will be moved to the end of
the current word before the completion code is called and hence
there will be no suffix.
_user_expand
This completer behaves similarly to the _expand completer but in-
stead performs expansions defined by users. The styles add-space
and sort styles specific to the _expand completer are usable with
_user_expand in addition to other styles handled more generally
by the completion system. The tag all-expansions is also avail-
able.
The expansion depends on the array style user-expand being de-
fined for the current context; remember that the context for com-
pleters is less specific than that for contextual completion as
the full context has not yet been determined. Elements of the
array may have one of the following forms:
$hash
hash is the name of an associative array. Note this is
not a full parameter expression, merely a $, suitably
quoted to prevent immediate expansion, followed by the
name of an associative array. If the trial expansion word
matches a key in hash, the resulting expansion is the cor-
responding value.
_func
_func is the name of a shell function whose name must be-
gin with _ but is not otherwise special to the completion
system. The function is called with the trial word as an
argument. If the word is to be expanded, the function
should set the array reply to a list of expansions. Op-
tionally, it can set REPLY to a word that will be used as
a description for the set of expansions. The return sta-
tus of the function is irrelevant.
BINDABLE COMMANDS
In addition to the context-dependent completions provided, which are ex-
pected to work in an intuitively obvious way, there are a few widgets
implementing special behaviour which can be bound separately to keys.
The following is a list of these and their default bindings.
_bash_completions
This function is used by two widgets, _bash_complete-word and
_bash_list-choices. It exists to provide compatibility with com-
pletion bindings in bash. The last character of the binding de-
termines what is completed: `!', command names; `$', environment
variables; `@', host names; `/', file names; `~' user names. In
bash, the binding preceded by `\e' gives completion, and preceded
by `^X' lists options. As some of these bindings clash with
standard zsh bindings, only `\e~' and `^X~' are bound by default.
To add the rest, the following should be added to .zshrc after
compinit has been run:
for key in '!' '$' '@' '/' '~'; do
bindkey "\e$key" _bash_complete-word
bindkey "^X$key" _bash_list-choices
done
This includes the bindings for `~' in case they were already
bound to something else; the completion code does not override
user bindings.
_correct_filename (^XC)
Correct the filename path at the cursor position. Allows up to
six errors in the name. Can also be called with an argument to
correct a filename path, independently of zle; the correction is
printed on standard output.
_correct_word (^Xc)
Performs correction of the current argument using the usual con-
textual completions as possible choices. This stores the string
`correct-word' in the function field of the context name and then
calls the _correct completer.
_expand_alias (^Xa)
This function can be used as a completer and as a bindable com-
mand. It expands the word the cursor is on if it is an alias.
The types of alias expanded can be controlled with the styles
regular, global and disabled.
When used as a bindable command there is one additional feature
that can be selected by setting the complete style to `true'. In
this case, if the word is not the name of an alias, _expand_alias
tries to complete the word to a full alias name without expanding
it. It leaves the cursor directly after the completed word so
that invoking _expand_alias once more will expand the now-com-
plete alias name.
_expand_word (^Xe)
Performs expansion on the current word: equivalent to the stan-
dard expand-word command, but using the _expand completer. Be-
fore calling it, the function field of the context is set to `ex-
pand-word'.
_generic
This function is not defined as a widget and not bound by de-
fault. However, it can be used to define a widget and will then
store the name of the widget in the function field of the context
and call the completion system. This allows custom completion
widgets with their own set of style settings to be defined eas-
ily. For example, to define a widget that performs normal com-
pletion and starts menu selection:
zle -C foo complete-word _generic
bindkey '...' foo
zstyle ':completion:foo:*' menu yes select=1
Note in particular that the completer style may be set for the
context in order to change the set of functions used to generate
possible matches. If _generic is called with arguments, those
are passed through to _main_complete as the list of completers in
place of those defined by the completer style.
_history_complete_word (\e/)
Complete words from the shell's command history. This uses the
list, remove-all-dups, sort, and stop styles.
_most_recent_file (^Xm)
Complete the name of the most recently modified file matching the
pattern on the command line (which may be blank). If given a nu-
meric argument N, complete the Nth most recently modified file.
Note the completion, if any, is always unique.
_next_tags (^Xn)
This command alters the set of matches used to that for the next
tag, or set of tags, either as given by the tag-order style or as
set by default; these matches would otherwise not be available.
Successive invocations of the command cycle through all possible
sets of tags.
_read_comp (^X^R)
Prompt the user for a string, and use that to perform completion
on the current word. There are two possibilities for the string.
First, it can be a set of words beginning `_', for example
`_files -/', in which case the function with any arguments will
be called to generate the completions. Unambiguous parts of the
function name will be completed automatically (normal completion
is not available at this point) until a space is typed.
Second, any other string will be passed as a set of arguments to
compadd and should hence be an expression specifying what should
be completed.
A very restricted set of editing commands is available when read-
ing the string: `DEL' and `^H' delete the last character; `^U'
deletes the line, and `^C' and `^G' abort the function, while
`RET' accepts the completion. Note the string is used verbatim
as a command line, so arguments must be quoted in accordance with
standard shell rules.
Once a string has been read, the next call to _read_comp will use
the existing string instead of reading a new one. To force a new
string to be read, call _read_comp with a numeric argument.
_complete_debug (^X?)
This widget performs ordinary completion, but captures in a tem-
porary file a trace of the shell commands executed by the comple-
tion system. Each completion attempt gets its own file. A com-
mand to view each of these files is pushed onto the editor buffer
stack.
_complete_help (^Xh)
This widget displays information about the context names, the
tags, and the completion functions used when completing at the
current cursor position. If given a numeric argument other than 1
(as in `ESC-2 ^Xh'), then the styles used and the contexts for
which they are used will be shown, too.
Note that the information about styles may be incomplete; it de-
pends on the information available from the completion functions
called, which in turn is determined by the user's own styles and
other settings.
_complete_help_generic
Unlike other commands listed here, this must be created as a nor-
mal ZLE widget rather than a completion widget (i.e. with zle
-N). It is used for generating help with a widget bound to the
_generic widget that is described above.
If this widget is created using the name of the function, as it
is by default, then when executed it will read a key sequence.
This is expected to be bound to a call to a completion function
that uses the _generic widget. That widget will be executed, and
information provided in the same format that the _complete_help
widget displays for contextual completion.
If the widget's name contains debug, for example if it is created
as `zle -N _complete_debug_generic _complete_help_generic', it
will read and execute the keystring for a generic widget as be-
fore, but then generate debugging information as done by _com-
plete_debug for contextual completion.
If the widget's name contains noread, it will not read a
keystring but instead arrange that the next use of a generic wid-
get run in the same shell will have the effect as described
above.
The widget works by setting the shell parameter
ZSH_TRACE_GENERIC_WIDGET which is read by _generic. Unsetting
the parameter cancels any pending effect of the noread form.
For example, after executing the following:
zle -N _complete_debug_generic _complete_help_generic
bindkey '^x:' _complete_debug_generic
typing `C-x :' followed by the key sequence for a generic widget
will cause trace output for that widget to be saved to a file.
_complete_tag (^Xt)
This widget completes symbol tags created by the etags or ctags
programmes (note there is no connection with the completion sys-
tem's tags) stored in a file TAGS, in the format used by etags,
or tags, in the format created by ctags. It will look back up
the path hierarchy for the first occurrence of either file; if
both exist, the file TAGS is preferred. You can specify the full
path to a TAGS or tags file by setting the parameter $TAGSFILE or
$tagsfile respectively. The corresponding completion tags used
are etags and vtags, after emacs and vi respectively.
UTILITY FUNCTIONS
Descriptions follow for utility functions that may be useful when writ-
ing completion functions. If functions are installed in subdirectories,
most of these reside in the Base subdirectory. Like the example func-
tions for commands in the distribution, the utility functions generating
matches all follow the convention of returning status zero if they gen-
erated completions and non-zero if no matching completions could be
added.
_absolute_command_paths
This function completes external commands as absolute paths (un-
like _command_names -e which completes their basenames). It
takes no arguments.
_all_labels [ -x ] [ -12VJ ] tag name descr [ command arg ... ]
This is a convenient interface to the _next_label function below,
implementing the loop shown in the _next_label example. The com-
mand and its arguments are called to generate the matches. The
options stored in the parameter name will automatically be in-
serted into the args passed to the command. Normally, they are
put directly after the command, but if one of the args is a sin-
gle hyphen, they are inserted directly before that. If the hy-
phen is the last argument, it will be removed from the argument
list before the command is called. This allows _all_labels to be
used in almost all cases where the matches can be generated by a
single call to the compadd builtin command or by a call to one of
the utility functions.
For example:
local expl
...
if _requested foo; then
...
_all_labels foo expl '...' compadd ... - $matches
fi
Will complete the strings from the matches parameter, using com-
padd with additional options which will take precedence over
those generated by _all_labels.
_alternative [ -O name ] [ -C name ] spec ...
This function is useful in simple cases where multiple tags are
available. Essentially it implements a loop like the one de-
scribed for the _tags function below.
The tags to use and the action to perform if a tag is requested
are described using the specs which are of the form: `tag:de-
scr:action'. The tags are offered using _tags and if the tag is
requested, the action is executed with the given description de-
scr. The actions are those accepted by the _arguments function
(described below), with the following exceptions:
• The `->state' and `=...' forms are not supported.
• The `((a\:bar b\:baz))' form does not need the colon to be
escaped, since the specs have no colon-separated fields
after the action.
For example, the action may be a simple function call:
_alternative \
'users:user:_users' \
'hosts:host:_hosts'
offers usernames and hostnames as possible matches, generated by
the _users and _hosts functions respectively.
Like _arguments, this function uses _all_labels to execute the
actions, which will loop over all sets of tags. Special handling
is only required if there is an additional valid tag, for example
inside a function called from _alternative.
The option `-O name' is used in the same way as by the _arguments
function. In other words, the elements of the name array will be
passed to compadd when executing an action.
Like _tags this function supports the -C option to give a differ-
ent name for the argument context field.
_arguments [ -nswWCRS ] [ -A pat ] [ -O name ] [ -M matchspec ]
[ : ] spec ...
_arguments [ opt ... ] -- [ -l ] [ -i pats ] [ -s pair ]
[ helpspec ...]
This function can be used to give a complete specification for
completion for a command whose arguments follow standard UNIX op-
tion and argument conventions.
Options Overview
Options to _arguments itself must be in separate words, i.e. -s
-w, not -sw. The options are followed by specs that describe op-
tions and arguments of the analyzed command. To avoid ambiguity,
all options to _arguments itself may be separated from the spec
forms by a single colon.
The `--' form is used to intuit spec forms from the help output
of the command being analyzed, and is described in detail below.
The opts for the `--' form are otherwise the same options as the
first form. Note that `-s' following `--' has a distinct meaning
from `-s' preceding `--', and both may appear.
The option switches -s, -S, -A, -w, and -W affect how _arguments
parses the analyzed command line's options. These switches are
useful for commands with standard argument parsing.
The options of _arguments have the following meanings:
-n With this option, _arguments sets the parameter NORMARG to
the position of the first normal argument in the $words
array, i.e. the position after the end of the options. If
that argument has not been reached, NORMARG is set to -1.
The caller should declare `integer NORMARG' if the -n op-
tion is passed; otherwise the parameter is not used.
-s Enable option stacking for single-letter options, whereby
multiple single-letter options may be combined into a sin-
gle word. For example, the two options `-x' and `-y' may
be combined into a single word `-xy'. By default, every
word corresponds to a single option name (`-xy' is a sin-
gle option named `xy').
Options beginning with a single hyphen or plus sign are
eligible for stacking; words beginning with two hyphens
are not.
Note that -s after -- has a different meaning, which is
documented in the segment entitled `Deriving spec forms
from the help output'.
-w In combination with -s, allow option stacking even if one
or more of the options take arguments. For example, if -x
takes an argument, with no -s, `-xy' is considered as a
single (unhandled) option; with -s, -xy is an option with
the argument `y'; with both -s and -w, -xy is the option
-x and the option -y with arguments to -x (and to -y, if
it takes arguments) still to come in subsequent words.
-W This option takes -w a stage further: it is possible to
complete single-letter options even after an argument that
occurs in the same word. However, it depends on the ac-
tion performed whether options will really be completed at
this point. For more control, use a utility function like
_guard as part of the action.
-C Modify the curcontext parameter for an action of the form
`->state'. This is discussed in detail below.
-R Return status 300 instead of zero when a $state is to be
handled, in the `->string' syntax.
-S Do not complete options after a `--' appearing on the
line, and ignore the `--'. For example, with -S, in the
line
foobar -x -- -y
the `-x' is considered an option, the `-y' is considered
an argument, and the `--' is considered to be neither.
-A pat Do not complete options after the first non-option argu-
ment on the line. pat is a pattern matching all strings
which are not to be taken as arguments. For example, to
make _arguments stop completing options after the first
normal argument, but ignoring all strings starting with a
hyphen even if they are not described by one of the opt-
specs, the form is `-A "-*"'.
-O name
Pass the elements of the array name as arguments to func-
tions called to execute actions. This is discussed in de-
tail below.
-M matchspec
Use the match specification matchspec for completing op-
tion names and values. The default matchspec allows par-
tial word completion after `_' and `-', such as completing
`-f-b' to `-foo-bar'. The default matchspec is:
r:|[_-]=* r:|=*
-0 When populating values of the `opt_args' associative ar-
ray, don't backslash-escape colons and backslashes and use
NUL rather than colon for joining multiple values. This
option is described in more detail below, under the head-
ing specs: actions.
specs: overview
Each of the following forms is a spec describing individual sets
of options or arguments on the command line being analyzed.
n:message:action
n::message:action
This describes the n'th normal argument. The message will
be printed above the matches generated and the action in-
dicates what can be completed in this position (see be-
low). If there are two colons before the message the ar-
gument is optional. If the message contains only white
space, nothing will be printed above the matches unless
the action adds an explanation string itself.
:message:action
::message:action
Similar, but describes the next argument, whatever number
that happens to be. If all arguments are specified in
this form in the correct order the numbers are unneces-
sary.
*:message:action
*::message:action
*:::message:action
This describes how arguments (usually non-option argu-
ments, those not beginning with - or +) are to be com-
pleted when neither of the first two forms was provided.
Any number of arguments can be completed in this fashion.
With two colons before the message, the words special ar-
ray and the CURRENT special parameter are modified to re-
fer only to the normal arguments when the action is exe-
cuted or evaluated. With three colons before the message
they are modified to refer only to the normal arguments
covered by this description.
optspec
optspec:...
This describes an option. The colon indicates handling
for one or more arguments to the option; if it is not
present, the option is assumed to take no arguments.
The following forms are available for the initial optspec,
whether or not the option has arguments.
*optspec
Here optspec is one of the remaining forms below.
This indicates the following optspec may be re-
peated. Otherwise if the corresponding option is
already present on the command line to the left of
the cursor it will not be offered again.
-optname
+optname
In the simplest form the optspec is just the option
name beginning with a minus or a plus sign, such as
`-foo'. The first argument for the option (if any)
must follow as a separate word directly after the
option.
Either of `-+optname' and `+-optname' can be used
to specify that -optname and +optname are both
valid.
In all the remaining forms, the leading `-' may be
replaced by or paired with `+' in this way.
-optname-
The first argument of the option must come directly
after the option name in the same word. For exam-
ple, `-foo-:...' specifies that the completed op-
tion and argument will look like `-fooarg'.
-optname+
The first argument may appear immediately after
optname in the same word, or may appear as a sepa-
rate word after the option. For example,
`-foo+:...' specifies that the completed option and
argument will look like either `-fooarg' or `-foo
arg'.
-optname=
The argument may appear as the next word, or in
same word as the option name provided that it is
separated from it by an equals sign, for example
`-foo=arg' or `-foo arg'.
-optname=-
The argument to the option must appear after an
equals sign in the same word, and may not be given
in the next argument.
optspec[explanation]
An explanation string may be appended to any of the
preceding forms of optspec by enclosing it in
brackets, as in `-q[query operation]'.
The verbose style is used to decide whether the ex-
planation strings are displayed with the option in
a completion listing.
If no bracketed explanation string is given but the
auto-description style is set and only one argument
is described for this optspec, the value of the
style is displayed, with any appearance of the se-
quence `%d' in it replaced by the message of the
first optarg that follows the optspec; see below.
It is possible for options with a literal `+' or `=' to
appear, but that character must be quoted, for example
`-\+'.
Each optarg following an optspec must take one of the fol-
lowing forms:
:message:action
::message:action
An argument to the option; message and action are
treated as for ordinary arguments. In the first
form, the argument is mandatory, and in the second
form it is optional.
This group may be repeated for options which take
multiple arguments. In other words, :message1:ac-
tion1:message2:action2 specifies that the option
takes two arguments.
:*pattern:message:action
:*pattern::message:action
:*pattern:::message:action
This describes multiple arguments. Only the last
optarg for an option taking multiple arguments may
be given in this form. If the pattern is empty
(i.e. :*:), all the remaining words on the line are
to be completed as described by the action; other-
wise, all the words up to and including a word
matching the pattern are to be completed using the
action.
Multiple colons are treated as for the `*:...'
forms for ordinary arguments: when the message is
preceded by two colons, the words special array and
the CURRENT special parameter are modified during
the execution or evaluation of the action to refer
only to the words after the option. When preceded
by three colons, they are modified to refer only to
the words covered by this description.
Any literal colon in an optname, message, or action must be pre-
ceded by a backslash, `\:'.
Each of the forms above may be preceded by a list in parentheses
of option names and argument numbers. If the given option is on
the command line, the options and arguments indicated in paren-
theses will not be offered. For example, `(-two -three
1)-one:...' completes the option `-one'; if this appears on the
command line, the options -two and -three and the first ordinary
argument will not be completed after it. `(-foo):...' specifies
an ordinary argument completion; -foo will not be completed if
that argument is already present.
Other items may appear in the list of excluded options to indi-
cate various other items that should not be applied when the cur-
rent specification is matched: a single star (*) for the rest ar-
guments (i.e. a specification of the form `*:...'); a colon (:)
for all normal (non-option-) arguments; and a hyphen (-) for all
options. For example, if `(*)' appears before an option and the
option appears on the command line, the list of remaining argu-
ments (those shown in the above table beginning with `*:') will
not be completed.
To aid in reuse of specifications, it is possible to precede any
of the forms above with `!'; then the form will no longer be com-
pleted, although if the option or argument appears on the command
line they will be skipped as normal. The main use for this is
when the arguments are given by an array, and _arguments is
called repeatedly for more specific contexts: on the first call
`_arguments $global_options' is used, and on subsequent calls
`_arguments !$^global_options'.
specs: actions
In each of the forms above the action determines how completions
should be generated. Except for the `->string' form below, the
action will be executed by calling the _all_labels function to
process all tag labels. No special handling of tags is needed
unless a function call introduces a new one.
The functions called to execute actions will be called with the
elements of the array named by the `-O name' option as arguments.
This can be used, for example, to pass the same set of options
for the compadd builtin to all actions.
The forms for action are as follows.
(single unquoted space)
This is useful where an argument is required but it is not
possible or desirable to generate matches for it. The
message will be displayed but no completions listed. Note
that even in this case the colon at the end of the message
is needed; it may only be omitted when neither a message
nor an action is given.
(item1 item2 ...)
One of a list of possible matches, for example:
:foo:(foo bar baz)
((item1\:desc1 ...))
Similar to the above, but with descriptions for each pos-
sible match. Note the backslash before the colon. For
example,
:foo:((a\:bar b\:baz))
The matches will be listed together with their descrip-
tions if the description style is set with the values tag
in the context.
->string
In this form, _arguments processes the arguments and op-
tions and then returns control to the calling function
with parameters set to indicate the state of processing;
the calling function then makes its own arrangements for
generating completions. For example, functions that im-
plement a state machine can use this type of action.
Where _arguments encounters action in the `->string' for-
mat, it will strip all leading and trailing whitespace
from string and set the array state to the set of all
strings for which an action is to be performed. The ele-
ments of the array state_descr are assigned the corre-
sponding message field from each optarg containing such an
action.
By default and in common with all other well behaved com-
pletion functions, _arguments returns status zero if it
was able to add matches and non-zero otherwise. However,
if the -R option is given, _arguments will instead return
a status of 300 to indicate that $state is to be handled.
In addition to $state and $state_descr, _arguments also
sets the global parameters `context', `line' and
`opt_args' as described below, and does not reset any
changes made to the special parameters such as PREFIX and
words. This gives the calling function the choice of re-
setting these parameters or propagating changes in them.
A function calling _arguments with at least one action
containing a `->string' must therefore declare appropriate
local parameters:
local context state state_descr line
typeset -A opt_args
to prevent _arguments from altering the global environ-
ment.
{eval-string}
A string in braces is evaluated as shell code to generate
matches. If the eval-string itself does not begin with an
opening parenthesis or brace it is split into separate
words before execution.
= action
If the action starts with `= ' (an equals sign followed by
a space), _arguments will insert the contents of the argu-
ment field of the current context as the new first element
in the words special array and increment the value of the
CURRENT special parameter. This has the effect of insert-
ing a dummy word onto the completion command line while
not changing the point at which completion is taking
place.
This is most useful with one of the specifiers that re-
strict the words on the command line on which the action
is to operate (the two- and three-colon forms above). One
particular use is when an action itself causes _arguments
on a restricted range; it is necessary to use this trick
to insert an appropriate command name into the range for
the second call to _arguments to be able to parse the
line.
word...
word...
This covers all forms other than those above. If the ac-
tion starts with a space, the remaining list of words will
be invoked unchanged.
Otherwise it will be invoked with some extra strings
placed after the first word; these are to be passed down
as options to the compadd builtin. They ensure that the
state specified by _arguments, in particular the descrip-
tions of options and arguments, is correctly passed to the
completion command. These additional arguments are taken
from the array parameter `expl'; this will be set up be-
fore executing the action and hence may be referred to in-
side it, typically in an expansion of the form `$expl[@]'
which preserves empty elements of the array.
During the performance of the action the array `line' will be set
to the normal arguments from the command line, i.e. the words
from the command line after the command name excluding all op-
tions and their arguments. Options are stored in the associative
array `opt_args' with option names as keys and their arguments as
the values. By default, all colons and backslashes in the value
are escaped with backslashes, and if an option has multiple argu-
ments (for example, when using an optspec of the form `*opt-
spec'), they are joined with (unescaped) colons. However, if the
-0 option was passed, no backslash escaping is performed, and
multiple values are joined with NUL bytes. For example, after
`zsh -o foo:foo -o bar:bar -o <TAB>', the contents of `opt_args'
would be
typeset -A opt_args=( [-o]='foo\:foo:bar\:bar:' )
by default, and
typeset -A opt_args=( [-o]=$'foo:foo\x00bar:bar\x00' )
if _arguments had been called with the -0 option.
The parameter `context' is set when returning to the calling
function to perform an action of the form `->string'. It is set
to an array of elements corresponding to the elements of $state.
Each element is a suitable name for the argument field of the
context: either a string of the form `option-opt-n' for the n'th
argument of the option -opt, or a string of the form `argument-n'
for the n'th argument. For `rest' arguments, that is those in
the list at the end not handled by position, n is the string
`rest'. For example, when completing the argument of the -o op-
tion, the name is `option-o-1', while for the second normal
(non-option-) argument it is `argument-2'.
Furthermore, during the evaluation of the action the context name
in the curcontext parameter is altered to append the same string
that is stored in the context parameter.
The option -C tells _arguments to modify the curcontext parameter
for an action of the form `->state'. This is the standard para-
meter used to keep track of the current context. Here it (and
not the context array) should be made local to the calling func-
tion to avoid passing back the modified value and should be ini-
tialised to the current value at the start of the function:
local curcontext="$curcontext"
This is useful where it is not possible for multiple states to be
valid together.
Grouping Options
Options can be grouped to simplify exclusion lists. A group is
introduced with `+' followed by a name for the group in the sub-
sequent word. Whole groups can then be referenced in an exclusion
list or a group name can be used to disambiguate between two
forms of the same option. For example:
_arguments \
'(group2--x)-a' \
+ group1 \
-m \
'(group2)-n' \
+ group2 \
-x -y
If the name of a group is specified in the form `(name)' then
only one value from that group will ever be completed; more for-
mally, all specifications are mutually exclusive to all other
specifications in that group. This is useful for defining options
that are aliases for each other. For example:
_arguments \
-a -b \
+ '(operation)' \
{-c,--compress}'[compress]' \
{-d,--decompress}'[decompress]' \
{-l,--list}'[list]'
If an option in a group appears on the command line, it is stored
in the associative array `opt_args' with 'group-option' as a key.
In the example above, a key `operation--c' is used if the option
`-c' is present on the command line.
Specifying Multiple Sets of Arguments
It is possible to specify multiple sets of options and arguments
with the sets separated by single hyphens. This differs from
groups in that sets are considered to be mutually exclusive of
each other.
Specifications before the first set and from any group are common
to all sets. For example:
_arguments \
-a \
- set1 \
-c \
- set2 \
-d \
':arg:(x2 y2)'
This defines two sets. When the command line contains the option
`-c', the `-d' option and the argument will not be considered
possible completions. When it contains `-d' or an argument, the
option `-c' will not be considered. However, after `-a' both
sets will still be considered valid.
As for groups, the name of a set may appear in exclusion lists,
either alone or preceding a normal option or argument specifica-
tion.
The completion code has to parse the command line separately for
each set. This can be slow so sets should only be used when nec-
essary. A useful alternative is often an option specification
with rest-arguments (as in `-foo:*:...'); here the option -foo
swallows up all remaining arguments as described by the optarg
definitions.
Deriving spec forms from the help output
The option `--' allows _arguments to work out the names of long
options that support the `--help' option which is standard in
many GNU commands. The command word is called with the argument
`--help' and the output examined for option names. Clearly, it
can be dangerous to pass this to commands which may not support
this option as the behaviour of the command is unspecified.
In addition to options, `_arguments --' will try to deduce the
types of arguments available for options when the form
`--opt=val' is valid. It is also possible to provide hints by
examining the help text of the command and adding helpspec of the
form `pattern:message:action'; note that other _arguments spec
forms are not used. The pattern is matched against the help text
for an option, and if it matches the message and action are used
as for other argument specifiers. The special case of `*:' means
both message and action are empty, which has the effect of caus-
ing options having no description in the help output to be or-
dered in listings ahead of options that have a description.
For example:
_arguments -- '*\*:toggle:(yes no)' \
'*=FILE*:file:_files' \
'*=DIR*:directory:_files -/' \
'*=PATH*:directory:_files -/'
Here, `yes' and `no' will be completed as the argument of options
whose description ends in a star; file names will be completed
for options that contain the substring `=FILE' in the descrip-
tion; and directories will be completed for options whose de-
scription contains `=DIR' or `=PATH'. The last three are in fact
the default and so need not be given explicitly, although it is
possible to override the use of these patterns. A typical help
text which uses this feature is:
-C, --directory=DIR change to directory DIR
so that the above specifications will cause directories to be
completed after `--directory', though not after `-C'.
Note also that _arguments tries to find out automatically if the
argument for an option is optional. This can be specified ex-
plicitly by doubling the colon before the message.
If the pattern ends in `(-)', this will be removed from the pat-
tern and the action will be used only directly after the `=', not
in the next word. This is the behaviour of a normal specifica-
tion defined with the form `=-'.
By default, the command (with the option `--help') is run after
resetting all the locale categories (except for LC_CTYPE) to `C'.
If the localized help output is known to work, the option `-l'
can be specified after the `_arguments --' so that the command is
run in the current locale.
The `_arguments --' can be followed by the option `-i patterns'
to give patterns for options which are not to be completed. The
patterns can be given as the name of an array parameter or as a
literal list in parentheses. For example,
_arguments -- -i \
"(--(en|dis)able-FEATURE*)"
will cause completion to ignore the options `--enable-FEATURE'
and `--disable-FEATURE' (this example is useful with GNU config-
ure).
The `_arguments --' form can also be followed by the option `-s
pair' to describe option aliases. The pair consists of a list of
alternating patterns and corresponding replacements, enclosed in
parens and quoted so that it forms a single argument word in the
_arguments call.
For example, some configure-script help output describes options
only as `--enable-foo', but the script also accepts the negated
form `--disable-foo'. To allow completion of the second form:
_arguments -- -s "((#s)--enable- --disable-)"
Miscellaneous notes
Finally, note that _arguments generally expects to be the primary
function handling any completion for which it is used. It may
have side effects which change the treatment of any matches added
by other functions called after it. To combine _arguments with
other functions, those functions should be called either before
_arguments, as an action within a spec, or in handlers for
`->state' actions.
Here is a more general example of the use of _arguments:
_arguments '-l+:left border:' \
'-format:paper size:(letter A4)' \
'*-copy:output file:_files::resolution:(300 600)' \
':postscript file:_files -g \*.\(ps\|eps\)' \
'*:page number:'
This describes three options: `-l', `-format', and `-copy'. The
first takes one argument described as `left border' for which no
completion will be offered because of the empty action. Its ar-
gument may come directly after the `-l' or it may be given as the
next word on the line.
The `-format' option takes one argument in the next word, de-
scribed as `paper size' for which only the strings `letter' and
`A4' will be completed.
The `-copy' option may appear more than once on the command line
and takes two arguments. The first is mandatory and will be com-
pleted as a filename. The second is optional (because of the
second colon before the description `resolution') and will be
completed from the strings `300' and `600'.
The last two descriptions say what should be completed as argu-
ments. The first describes the first argument as a `postscript
file' and makes files ending in `ps' or `eps' be completed. The
last description gives all other arguments the description `page
number' but does not offer completions.
_cache_invalid cache_identifier
This function returns status zero if the completions cache corre-
sponding to the given cache identifier needs rebuilding. It de-
termines this by looking up the cache-policy style for the cur-
rent context. This should provide a function name which is run
with the full path to the relevant cache file as the only argu-
ment.
Example:
_example_caching_policy () {
# rebuild if cache is more than a week old
local -a oldp
oldp=( "$1"(Nm+7) )
(( $#oldp ))
}
_call_function return name [ arg ... ]
If a function name exists, it is called with the arguments args.
The return argument gives the name of a parameter in which the
return status from the function name should be stored; if return
is empty or a single hyphen it is ignored.
The return status of _call_function itself is zero if the func-
tion name exists and was called and non-zero otherwise.
_call_program [ -l ] [ -p ] tag string ...
This function provides a mechanism for the user to override the
use of an external command. It looks up the command style with
the supplied tag. If the style is set, its value is used as the
command to execute. The strings from the call to _call_program,
or from the style if set, are concatenated with spaces between
them and the resulting string is evaluated. The return status is
the return status of the command called.
By default, the command is run in an environment where all the
locale categories (except for LC_CTYPE) are reset to `C' by call-
ing the utility function _comp_locale (see below). If the option
`-l' is given, the command is run with the current locale.
If the option `-p' is supplied it indicates that the command out-
put is influenced by the permissions it is run with. If the
gain-privileges style is set to true, _call_program will make use
of commands such as sudo, if present on the command-line, to
match the permissions to whatever the final command is likely to
run under. When looking up the gain-privileges and command
styles, the command component of the zstyle context will end with
a slash (`/') followed by the command that would be used to gain
privileges.
_combination [ -s pattern ] tag style spec ... field opts ...
This function is used to complete combinations of values, for
example pairs of hostnames and usernames. The style argument
gives the style which defines the pairs; it is looked up in a
context with the tag specified.
The style name consists of field names separated by hyphens, for
example `users-hosts-ports'. For each field for a value is al-
ready known, a spec of the form `field=pattern' is given. For
example, if the command line so far specifies a user `pws', the
argument `users=pws' should appear.
The next argument with no equals sign is taken as the name of the
field for which completions should be generated (presumably not
one of the fields for which the value is known).
The matches generated will be taken from the value of the style.
These should contain the possible values for the combinations in
the appropriate order (users, hosts, ports in the example above).
The values for the different fields are separated by colons.
This can be altered with the option -s to _combination which
specifies a pattern. Typically this is a character class, as for
example `-s "[:@]"' in the case of the users-hosts style. Each
`field=pattern' specification restricts the completions which ap-
ply to elements of the style with appropriately matching fields.
If no style with the given name is defined for the given tag, or
if none of the strings in style's value match, but a function
name of the required field preceded by an underscore is defined,
that function will be called to generate the matches. For exam-
ple, if there is no `users-hosts-ports' or no matching hostname
when a host is required, the function `_hosts' will automatically
be called.
If the same name is used for more than one field, in both the
`field=pattern' and the argument that gives the name of the field
to be completed, the number of the field (starting with one) may
be given after the fieldname, separated from it by a colon.
All arguments after the required field name are passed to compadd
when generating matches from the style value, or to the functions
for the fields if they are called.
_command_names [ -e | - ]
This function completes words that are valid at command position:
names of aliases, builtins, hashed commands, functions, and so
on. With the -e flag, only hashed commands are completed. The -
flag is ignored.
_comp_locale
This function resets all the locale categories other than
LC_CTYPE to `C' so that the output from external commands can be
easily analyzed by the completion system. LC_CTYPE retains the
current value (taking LC_ALL and LANG into account), ensuring
that non-ASCII characters in file names are still handled prop-
erly.
This function should normally be run only in a subshell, because
the new locale is exported to the environment. Typical usage
would be `$(_comp_locale; command ...)'.
_completers [ -p ]
This function completes names of completers.
-p Include the leading underscore (`_') in the matches.
_default
This function corresponds to the -default- special context which
is applied where no completion is defined. It is useful to call
it under certain error conditions such as completion after an un-
recognised subcommand. This applies the concept of graceful
degradation to the completion system, allowing it to fallback on
basic completion of commonly useful things like filenames.
_describe [-12JVx] [ -oO | -t tag ] descr name1 [ name2 ] [ opt ... ]
[ -- name1 [ name2 ] [ opt ... ] ... ]
This function associates completions with descriptions. Multiple
groups separated by -- can be supplied, potentially with differ-
ent completion options opts.
The descr is taken as a string to display above the matches if
the format style for the descriptions tag is set. This is fol-
lowed by one or two names of arrays followed by options to pass
to compadd. The array name1 contains the possible completions
with their descriptions in the form `completion:description'.
Any literal colons in completion must be quoted with a backslash.
If a name2 is given, it should have the same number of elements
as name1; in this case the corresponding elements are added as
possible completions instead of the completion strings from
name1. The completion list will retain the descriptions from
name1. Finally, a set of completion options can appear.
If the option `-o' appears before the first argument, the matches
added will be treated as names of command options (N.B. not shell
options), typically following a `-', `--' or `+' on the command
line. In this case _describe uses the prefix-hidden, pre-
fix-needed and verbose styles to find out if the strings should
be added as completions and if the descriptions should be shown.
Without the `-o' option, only the verbose style is used to decide
how descriptions are shown. If `-O' is used instead of `-o',
command options are completed as above but _describe will not
handle the prefix-needed style.
With the -t option a tag can be specified. The default is `val-
ues' or, if the -o option is given, `options'.
The options -1, -2, -J, -V, -x are passed to _next_label.
If selected by the list-grouped style, strings with the same de-
scription will appear together in the list.
_describe uses the _all_labels function to generate the matches,
so it does not need to appear inside a loop over tag labels.
_description [ -x ] [ -12VJ ] tag name descr [ spec ... ]
This function is not to be confused with the previous one; it is
used as a helper function for creating options to compadd. It is
buried inside many of the higher level completion functions and
so often does not need to be called directly.
The styles listed below are tested in the current context using
the given tag. The resulting options for compadd are put into
the array named name (this is traditionally `expl', but this con-
vention is not enforced). The description for the corresponding
set of matches is passed to the function in descr.
The styles tested are: format, hidden, matcher, ignore-line, ig-
nored-patterns, group-name and sort. The format style is first
tested for the given tag and then for the descriptions tag if no
value was found, while the remainder are only tested for the tag
given as the first argument. The function also calls _setup
which tests some more styles.
The string returned by the format style (if any) will be modified
so that the sequence `%d' is replaced by the descr given as the
third argument without any leading or trailing white space. If,
after removing the white space, the descr is the empty string,
the format style will not be used and the options put into the
name array will not contain an explanation string to be displayed
above the matches.
If _description is called with more than three arguments, the ad-
ditional specs should be of the form `char:str'. These supply
escape sequence replacements for the format style: every appear-
ance of `%char' will be replaced by string. If no additional
specs are given but the description in descr conforms to a common
form then further escape sequences are set for elements of that
description. These elements correspond to a default value
(`%o'), the units (`%m') range of acceptable values (`%r') and
the remaining initial part of the description (`%h'). The form
the description takes consists of specifying the units and range
in parentheses and the default value in square brackets, for ex-
ample:
_description times expl 'timeout (seconds) (0-60) [20]'
It is possible to use zformat conditional expressions when
styling these elements. So, for example, to add `default:' as a
tag but only when there is a default value to show, the format
style might include `%(o.default: %o.)'.
If the -x option is given, the description will be passed to com-
padd using the -x option instead of the default -X. This means
that the description will be displayed even if there are no cor-
responding matches.
The options placed in the array name take account of the
group-name style, so matches are placed in a separate group where
necessary. The group normally has its elements sorted (by pass-
ing the option -J to compadd), but if an option starting with
`-V', `-J', `-1', or `-2' is passed to _description, that option
will be included in the array. Hence it is possible for the com-
pletion group to be unsorted by giving the option `-V', `-1V', or
`-2V'.
In most cases, the function will be used like this:
local expl
_description files expl file
compadd "$expl[@]" - "$files[@]"
Note the use of the parameter expl, the hyphen, and the list of
matches. Almost all calls to compadd within the completion sys-
tem use a similar format; this ensures that user-specified styles
are correctly passed down to the builtins which implement the in-
ternals of completion.
_dir_list [ -s sep ] [ -S ]
Complete a list of directory names separated by colons (the same
format as $PATH).
-s sep Use sep as separator between items. sep defaults to a
colon (`:').
-S Add sep instead of slash (`/') as an autoremoveable suf-
fix.
_dispatch context string ...
This sets the current context to context and looks for completion
functions to handle this context by hunting through the list of
command names or special contexts (as described above for com-
pdef) given as strings. The first completion function to be de-
fined for one of the contexts in the list is used to generate
matches. Typically, the last string is -default- to cause the
function for default completion to be used as a fallback.
The function sets the parameter $service to the string being
tried, and sets the context/command field (the fourth) of the
$curcontext parameter to the context given as the first argument.
_email_addresses [ -c ] [ -n plugin ]
Complete email addresses. Addresses are provided by plugins.
-c Complete bare localhost@domain.tld addresses, without a
name part or a comment. Without this option, RFC822
`Firstname Lastname <address>' strings are completed.
-n plugin
Complete aliases from plugin.
The following plugins are available by default: _email-ldap (see
the filter style), _email-local (completes user@hostname Unix ad-
dresses), _email-mail (completes aliases from ~/.mailrc),
_email-mush, _email-mutt, and _email-pine.
Addresses from the _email-foo plugin are added under the tag
`email-foo'.
Writing plugins
Plugins are written as separate functions with names starting
with `_email-'. They are invoked with the -c option and compadd
options. They should either do their own completion or set the
$reply array to a list of `alias:address' elements and return
300. New plugins will be picked up and run automatically.
_files The function _files is a wrapper around _path_files. It supports
all of the same functionality, with some enhancements -- notably,
it respects the list-dirs-first style, and it allows users to
override the behaviour of the -g and -/ options with the
file-patterns style. _files should therefore be preferred over
_path_files in most cases.
This function accepts the full set of options allowed by
_path_files, described below.
_gnu_generic
This function is a simple wrapper around the _arguments function
described above. It can be used to determine automatically the
long options understood by commands that produce a list when
passed the option `--help'. It is intended to be used as a
top-level completion function in its own right. For example, to
enable option completion for the commands foo and bar, use
compdef _gnu_generic foo bar
after the call to compinit.
The completion system as supplied is conservative in its use of
this function, since it is important to be sure the command un-
derstands the option `--help'.
_guard [ options ] pattern descr
This function displays descr if pattern matches the string to be
completed. It is intended to be used in the action for the spec-
ifications passed to _arguments and similar functions.
The return status is zero if the message was displayed and the
word to complete is not empty, and non-zero otherwise.
The pattern may be preceded by any of the options understood by
compadd that are passed down from _description, namely -M, -J,
-V, -1, -2, -n, -F and -X. All of these options will be ignored.
This fits in conveniently with the argument-passing conventions
of actions for _arguments.
As an example, consider a command taking the options -n and
-none, where -n must be followed by a numeric value in the same
word. By using:
_arguments '-n-: :_guard "[0-9]#" "numeric value"' '-none'
_arguments can be made to both display the message `numeric
value' and complete options after `-n<TAB>'. If the `-n' is al-
ready followed by one or more digits (the pattern passed to
_guard) only the message will be displayed; if the `-n' is fol-
lowed by another character, only options are completed.
_message [ -r12 ] [ -VJ group ] descr
_message -e [ tag ] descr
The descr is used in the same way as the third argument to the
_description function, except that the resulting string will al-
ways be shown whether or not matches were generated. This is
useful for displaying a help message in places where no comple-
tions can be generated.
The format style is examined with the messages tag to find a mes-
sage; the usual tag, descriptions, is used only if the style is
not set with the former.
If the -r option is given, no style is used; the descr is taken
literally as the string to display. This is most useful when the
descr comes from a pre-processed argument list which already con-
tains an expanded description. Note that this option does not
disable the `%'-sequence parsing done by compadd.
The -12VJ options and the group are passed to compadd and hence
determine the group the message string is added to.
The second -e form gives a description for completions with the
tag tag to be shown even if there are no matches for that tag.
This form is called by _arguments in the event that there is no
action for an option specification. The tag can be omitted and
if so the tag is taken from the parameter $curtag; this is main-
tained by the completion system and so is usually correct. Note
that if there are no matches at the time this function is called,
compstate[insert] is cleared, so additional matches generated
later are not inserted on the command line.
_multi_parts [ -i ] sep array
The argument sep is a separator character. The array may be ei-
ther the name of an array parameter or a literal array in the
form `(foo bar)', a parenthesised list of words separated by
whitespace. The possible completions are the strings from the
array. However, each chunk delimited by sep will be completed
separately. For example, the _tar function uses `_multi_parts /
patharray' to complete partial file paths from the given array of
complete file paths.
The -i option causes _multi_parts to insert a unique match even
if that requires multiple separators to be inserted. This is not
usually the expected behaviour with filenames, but certain other
types of completion, for example those with a fixed set of possi-
bilities, may be more suited to this form.
Like other utility functions, this function accepts the `-V',
`-J', `-1', `-2', `-n', `-f', `-X', `-M', `-P', `-S', `-r', `-R',
and `-q' options and passes them to the compadd builtin.
_next_label [ -x ] [ -12VJ ] tag name descr [ option ... ]
This function is used to implement the loop over different tag
labels for a particular tag as described above for the tag-order
style. On each call it checks to see if there are any more tag
labels; if there is it returns status zero, otherwise non-zero.
As this function requires a current tag to be set, it must always
follow a call to _tags or _requested.
The -x12VJ options and the first three arguments are passed to
the _description function. Where appropriate the tag will be re-
placed by a tag label in this call. Any description given in the
tag-order style is preferred to the descr passed to _next_label.
The options given after the descr are set in the parameter given
by name, and hence are to be passed to compadd or whatever func-
tion is called to add the matches.
Here is a typical use of this function for the tag foo. The call
to _requested determines if tag foo is required at all; the loop
over _next_label handles any labels defined for the tag in the
tag-order style.
local expl ret=1
...
if _requested foo; then
...
while _next_label foo expl '...'; do
compadd "$expl[@]" ... && ret=0
done
...
fi
return ret
_normal [ -P | -p precommand ]
This is the standard function called to handle completion outside
any special -context-. It is called both to complete the command
word and also the arguments for a command. In the second case,
_normal looks for a special completion for that command, and if
there is none it uses the completion for the -default- context.
A second use is to reexamine the command line specified by the
$words array and the $CURRENT parameter after those have been
modified. For example, the function _precommand, which completes
after precommand specifiers such as nohup, removes the first word
from the words array, decrements the CURRENT parameter, then
calls `_normal -p $service'. The effect is that `nohup cmd ...'
is treated in the same way as `cmd ...'.
-P Reset the list of precommands. This option should be used
if completing a command line which allows internal com-
mands (e.g. builtins and functions) regardless of prior
precommands (e.g. `zsh -c').
-p precommand
Append precommand to the list of precommands. This option
should be used in nearly all cases in which -P is not ap-
plicable.
If the command name matches one of the patterns given by one of
the options -p or -P to compdef, the corresponding completion
function is called and then the parameter _compskip is checked.
If it is set completion is terminated at that point even if no
matches have been found. This is the same effect as in the
-first- context.
_numbers [ option ... ] [ description ] [ suffix ... ]
This can be used where a number is followed by a suffix to indi-
cate the units. The unit suffixes are completed and can also be
included in the description used when completion is invoked for
the preceding number.
In addition to common compadd options, _numbers accepts the fol-
lowing options:
-t tag Specify a tag to use instead of the default of numbers.
-u units
Indicate the default units for the number, e.g. bytes.
-l min Specify the lowest possible value for the number.
-m max Specify the highest possible value for the number.
-d default
Specify the default value.
-N Allow negative numbers. This is implied if the range in-
cludes a negative.
-f Allow decimal numbers.
Where a particular suffix represents the default units for a num-
ber, it should be prefixed with a colon. Additionally, suffixes
can be followed by a colon and a description. So for example,
the following allows the age of something to be specified, either
in seconds or with an optional suffix with a longer unit of time:
_numbers -u seconds age :s:seconds m:minutes h:hours d:days
It is typically helpful for units to be presented in order of
magnitude when completed. To facilitate this, the order in which
they are given is preserved.
When the format style is looked up with the descriptions tag or
the tag specified with -t, the list of suffixes is available as a
`%x' escape sequence. This is in addition to the usual sequences
documented under the format style. The form this list takes can
also be configured. To this end, the format style is first looked
up with the tag unit-suffixes. The retrieved format is applied to
each suffix in turn and the results are then concatenated to form
the completed list. For the unit-suffixes format, `%x' expands to
the individual suffix and `%X' to its description. %d' indicates
a default suffix and can be used in a condition. The index and
reverse index are set in `%i' and `%r' respectively and are use-
ful for text included only with the first and last suffixes in
the list. So for example, the following joins the suffixes to-
gether as a comma-separated list:
zstyle ':completion:*:unit-suffixes' format '%x%(r::,)'
_options
This can be used to complete the names of shell options. It pro-
vides a matcher specification that ignores a leading `no', ig-
nores underscores and allows upper-case letters to match their
lower-case counterparts (for example, `glob', `noglob', `NO_GLOB'
are all completed). Any arguments are propagated to the compadd
builtin.
_options_set and _options_unset
These functions complete only set or unset options, with the same
matching specification used in the _options function.
Note that you need to uncomment a few lines in the _main_complete
function for these functions to work properly. The lines in
question are used to store the option settings in effect before
the completion widget locally sets the options it needs. Hence
these functions are not generally used by the completion system.
_parameters
This is used to complete the names of shell parameters.
The option `-g pattern' limits the completion to parameters whose
type matches the pattern. The type of a parameter is that shown
by `print ${(t)param}', hence judicious use of `*' in pattern is
probably necessary.
All other arguments are passed to the compadd builtin.
_path_files
This function is used throughout the completion system to com-
plete filenames. It allows completion of partial paths. For ex-
ample, the string `/u/i/s/sig' may be completed to `/usr/in-
clude/sys/signal.h'.
The options accepted by both _path_files and _files are:
-f Complete all filenames. This is the default.
-/ Specifies that only directories should be completed.
-g pattern
Specifies that only files matching the pattern should be
completed.
-W paths
Specifies path prefixes that are to be prepended to the
string from the command line to generate the filenames but
that should not be inserted as completions nor shown in
completion listings. Here, paths may be the name of an
array parameter, a literal list of paths enclosed in
parentheses or an absolute pathname.
-F ignored-files
This behaves as for the corresponding option to the com-
padd builtin. It gives direct control over which file-
names should be ignored. If the option is not present,
the ignored-patterns style is used.
Both _path_files and _files also accept the following options
which are passed to compadd: `-J', `-V', `-1', `-2', `-n', `-X',
`-M', `-P', `-S', `-q', `-r', and `-R'.
Finally, the _path_files function uses the styles expand, am-
biguous, special-dirs, list-suffixes and file-sort described
above.
_pick_variant [ -b builtin-label ] [ -c command ] [ -r name ]
label=pattern ... label [ arg ... ]
This function is used to resolve situations where a single com-
mand name requires more than one type of handling, either because
it has more than one variant or because there is a name clash be-
tween two different commands.
The command to run is taken from the first element of the array
words unless this is overridden by the option -c. This command
is run and its output is compared with a series of patterns. Ar-
guments to be passed to the command can be specified at the end
after all the other arguments. The patterns to try in order are
given by the arguments label=pattern; if the output of `command
arg ...' contains pattern, then label is selected as the label
for the command variant. If none of the patterns match, the fi-
nal command label is selected and status 1 is returned.
If the `-b builtin-label' is given, the command is tested to see
if it is provided as a shell builtin, possibly autoloaded; if so,
the label builtin-label is selected as the label for the variant.
If the `-r name' is given, the label picked is stored in the pa-
rameter named name.
The results are also cached in the _cmd_variant associative array
indexed by the name of the command run.
_regex_arguments name spec ...
This function generates a completion function name which matches
the specifications specs, a set of regular expressions as de-
scribed below. After running _regex_arguments, the function name
should be called as a normal completion function. The pattern to
be matched is given by the contents of the words array up to the
current cursor position joined together with null characters; no
quotation is applied.
The arguments are grouped as sets of alternatives separated by
`|', which are tried one after the other until one matches. Each
alternative consists of a one or more specifications which are
tried left to right, with each pattern matched being stripped in
turn from the command line being tested, until all of the group
succeeds or until one fails; in the latter case, the next alter-
native is tried. This structure can be repeated to arbitrary
depth by using parentheses; matching proceeds from inside to out-
side.
A special procedure is applied if no test succeeds but the re-
maining command line string contains no null character (implying
the remaining word is the one for which completions are to be
generated). The completion target is restricted to the remaining
word and any actions for the corresponding patterns are executed.
In this case, nothing is stripped from the command line string.
The order of evaluation of the actions can be determined by the
tag-order style; the various formats supported by _alternative
can be used in action. The descr is used for setting up the ar-
ray parameter expl.
Specification arguments take one of following forms, in which
metacharacters such as `(', `)', `#' and `|' should be quoted.
/pattern/ [%lookahead%] [-guard] [:tag:descr:action]
This is a single primitive component. The function tests
whether the combined pattern `(#b)((#B)pattern)lookahead*'
matches the command line string. If so, `guard' is evalu-
ated and its return status is examined to determine if the
test has succeeded. The pattern string `[]' is guaranteed
never to match. The lookahead is not stripped from the
command line before the next pattern is examined.
The argument starting with : is used in the same manner as
an argument to _alternative.
A component is used as follows: pattern is tested to see
if the component already exists on the command line. If
it does, any following specifications are examined to find
something to complete. If a component is reached but no
such pattern exists yet on the command line, the string
containing the action is used to generate matches to in-
sert at that point.
/pattern/+ [%lookahead%] [-guard] [:tag:descr:action]
This is similar to `/pattern/ ...' but the left part of
the command line string (i.e. the part already matched by
previous patterns) is also considered part of the comple-
tion target.
/pattern/- [%lookahead%] [-guard] [:tag:descr:action]
This is similar to `/pattern/ ...' but the actions of the
current and previously matched patterns are ignored even
if the following `pattern' matches the empty string.
( spec )
Parentheses may be used to groups specs; note each paren-
thesis is a single argument to _regex_arguments.
spec # This allows any number of repetitions of spec.
spec spec
The two specs are to be matched one after the other as de-
scribed above.
spec | spec
Either of the two specs can be matched.
The function _regex_words can be used as a helper function to
generate matches for a set of alternative words possibly with
their own arguments as a command line argument.
Examples:
_regex_arguments _tst /$'[^\0]#\0'/ \
/$'[^\0]#\0'/ :'compadd aaa'
This generates a function _tst that completes aaa as its only ar-
gument. The tag and description for the action have been omitted
for brevity (this works but is not recommended in normal use).
The first component matches the command word, which is arbitrary;
the second matches any argument. As the argument is also arbi-
trary, any following component would not depend on aaa being
present.
_regex_arguments _tst /$'[^\0]#\0'/ \
/$'aaa\0'/ :'compadd aaa'
This is a more typical use; it is similar, but any following pat-
terns would only match if aaa was present as the first argument.
_regex_arguments _tst /$'[^\0]#\0'/ \( \
/$'aaa\0'/ :'compadd aaa' \
/$'bbb\0'/ :'compadd bbb' \) \#
In this example, an indefinite number of command arguments may be
completed. Odd arguments are completed as aaa and even arguments
as bbb. Completion fails unless the set of aaa and bbb arguments
before the current one is matched correctly.
_regex_arguments _tst /$'[^\0]#\0'/ \
\( /$'aaa\0'/ :'compadd aaa' \| \
/$'bbb\0'/ :'compadd bbb' \) \#
This is similar, but either aaa or bbb may be completed for any
argument. In this case _regex_words could be used to generate a
suitable expression for the arguments.
_regex_words tag description spec ...
This function can be used to generate arguments for the
_regex_arguments command which may be inserted at any point where
a set of rules is expected. The tag and description give a stan-
dard tag and description pertaining to the current context. Each
spec contains two or three arguments separated by a colon: note
that there is no leading colon in this case.
Each spec gives one of a set of words that may be completed at
this point, together with arguments. It is thus roughly equiva-
lent to the _arguments function when used in normal (non-regex)
completion.
The part of the spec before the first colon is the word to be
completed. This may contain a *; the entire word, before and af-
ter the * is completed, but only the text before the * is re-
quired for the context to be matched, so that further arguments
may be completed after the abbreviated form.
The second part of spec is a description for the word being com-
pleted.
The optional third part of the spec describes how words following
the one being completed are themselves to be completed. It will
be evaluated in order to avoid problems with quoting. This means
that typically it contains a reference to an array containing
previously generated regex arguments.
The option -t term specifies a terminator for the word instead of
the usual space. This is handled as an auto-removable suffix in
the manner of the option -s sep to _values.
The result of the processing by _regex_words is placed in the ar-
ray reply, which should be made local to the calling function.
If the set of words and arguments may be matched repeatedly, a #
should be appended to the generated array at that point.
For example:
local -a reply
_regex_words mydb-commands 'mydb commands' \
'add:add an entry to mydb:$mydb_add_cmds' \
'show:show entries in mydb'
_regex_arguments _mydb "$reply[@]"
_mydb "$@"
This shows a completion function for a command mydb which takes
two command arguments, add and show. show takes no arguments,
while the arguments for add have already been prepared in an ar-
ray mydb_add_cmds, quite possibly by a previous call to
_regex_words.
_requested [ -x ] [ -12VJ ] tag [ name descr [ command [ arg ... ] ]
This function is called to decide whether a tag already regis-
tered by a call to _tags (see below) has been requested by the
user and hence completion should be performed for it. It returns
status zero if the tag is requested and non-zero otherwise. The
function is typically used as part of a loop over different tags
as follows:
_tags foo bar baz
while _tags; do
if _requested foo; then
... # perform completion for foo
fi
... # test the tags bar and baz in the same way
... # exit loop if matches were generated
done
Note that the test for whether matches were generated is not per-
formed until the end of the _tags loop. This is so that the user
can set the tag-order style to specify a set of tags to be com-
pleted at the same time.
If name and descr are given, _requested calls the _description
function with these arguments together with the options passed to
_requested.
If command is given, the _all_labels function will be called im-
mediately with the same arguments. In simple cases this makes it
possible to perform the test for the tag and the matching in one
go. For example:
local expl ret=1
_tags foo bar baz
while _tags; do
_requested foo expl 'description' \
compadd foobar foobaz && ret=0
...
(( ret )) || break
done
If the command is not compadd, it must nevertheless be prepared
to handle the same options.
_retrieve_cache cache_identifier
This function retrieves completion information from the file
given by cache_identifier, stored in a directory specified by the
cache-path style which defaults to ~/.zcompcache. The return
status is zero if retrieval was successful. It will only attempt
retrieval if the use-cache style is set, so you can call this
function without worrying about whether the user wanted to use
the caching layer.
See _store_cache below for more details.
_sep_parts
This function is passed alternating arrays and separators as ar-
guments. The arrays specify completions for parts of strings to
be separated by the separators. The arrays may be the names of
array parameters or a quoted list of words in parentheses. For
example, with the array `hosts=(ftp news)' the call `_sep_parts
'(foo bar)' @ hosts' will complete the string `f' to `foo' and
the string `b@n' to `bar@news'.
This function accepts the compadd options `-V', `-J', `-1', `-2',
`-n', `-X', `-M', `-P', `-S', `-r', `-R', and `-q' and passes
them on to the compadd builtin used to add the matches.
_sequence [ -s sep ] [ -n max ] [ -d ] function [ - ] ...
This function is a wrapper to other functions for completing
items in a separated list. The same function is used to complete
each item in the list. The separator is specified with the -s op-
tion. If -s is omitted it will use `,'. Duplicate values are not
matched unless -d is specified. If there is a fixed or maximum
number of items in the list, this can be specified with the -n
option.
Common compadd options are passed on to the function. It is pos-
sible to use compadd directly with _sequence, though _values may
be more appropriate in this situation.
_setup tag [ group ]
This function sets up the special parameters used by the comple-
tion system appropriately for the tag given as the first argu-
ment. It uses the styles list-colors, list-packed,
list-rows-first, last-prompt, accept-exact, menu and force-list.
The optional group supplies the name of the group in which the
matches will be placed. If it is not given, the tag is used as
the group name.
This function is called automatically from _description and hence
is not normally called explicitly.
_store_cache cache_identifier param ...
This function, together with _retrieve_cache and _cache_invalid,
implements a caching layer which can be used in any completion
function. Data obtained by costly operations are stored in para-
meters; this function then dumps the values of those parameters
to a file. The data can then be retrieved quickly from that file
via _retrieve_cache, even in different instances of the shell.
The cache_identifier specifies the file which the data should be
dumped to. The file is stored in a directory specified by the
cache-path style which defaults to ~/.zcompcache. The remaining
params arguments are the parameters to dump to the file.
The return status is zero if storage was successful. The func-
tion will only attempt storage if the use-cache style is set, so
you can call this function without worrying about whether the
user wanted to use the caching layer.
The completion function may avoid calling _retrieve_cache when it
already has the completion data available as parameters. How-
ever, in that case it should call _cache_invalid to check whether
the data in the parameters and in the cache are still valid.
See the _perl_modules completion function for a simple example of
the usage of the caching layer.
_tags [ [ -C name ] tag ... ]
If called with arguments, these are taken to be the names of tags
valid for completions in the current context. These tags are
stored internally and sorted by using the tag-order style.
Next, _tags is called repeatedly without arguments from the same
completion function. This successively selects the first, sec-
ond, etc. set of tags requested by the user. The return status
is zero if at least one of the tags is requested and non-zero
otherwise. To test if a particular tag is to be tried, the _re-
quested function should be called (see above).
If `-C name' is given, name is temporarily stored in the argument
field (the fifth) of the context in the curcontext parameter dur-
ing the call to _tags; the field is restored on exit. This al-
lows _tags to use a more specific context without having to
change and reset the curcontext parameter (which has the same ef-
fect).
_tilde_files
Like _files, but resolve leading tildes according to the rules of
filename expansion, so the suggested completions don't start with
a `~' even if the filename on the command-line does.
_values [ -O name ] [ -s sep ] [ -S sep ] [ -wC ] desc spec ...
This is used to complete arbitrary keywords (values) and their
arguments, or lists of such combinations.
If the first argument is the option `-O name', it will be used in
the same way as by the _arguments function. In other words, the
elements of the name array will be passed to compadd when execut-
ing an action.
If the first argument (or the first argument after `-O name') is
`-s', the next argument is used as the character that separates
multiple values. This character is automatically added after
each value in an auto-removable fashion (see below); all values
completed by `_values -s' appear in the same word on the command
line, unlike completion using _arguments. If this option is not
present, only a single value will be completed per word.
Normally, _values will only use the current word to determine
which values are already present on the command line and hence
are not to be completed again. If the -w option is given, other
arguments are examined as well.
The first non-option argument, desc, is used as a string to print
as a description before listing the values.
All other arguments describe the possible values and their argu-
ments in the same format used for the description of options by
the _arguments function (see above). The only differences are
that no minus or plus sign is required at the beginning, values
can have only one argument, and the forms of action beginning
with an equal sign are not supported.
The character separating a value from its argument can be set us-
ing the option -S (like -s, followed by the character to use as
the separator in the next argument). By default the equals sign
will be used as the separator between values and arguments.
Example:
_values -s , 'description' \
'*foo[bar]' \
'(two)*one[number]:first count:' \
'two[another number]::second count:(1 2 3)'
This describes three possible values: `foo', `one', and `two'.
The first is described as `bar', takes no argument and may appear
more than once. The second is described as `number', may appear
more than once, and takes one mandatory argument described as
`first count'; no action is specified, so it will not be com-
pleted. The `(two)' at the beginning says that if the value
`one' is on the line, the value `two' will no longer be consid-
ered a possible completion. Finally, the last value (`two') is
described as `another number' and takes an optional argument de-
scribed as `second count' for which the completions (to appear
after an `=') are `1', `2', and `3'. The _values function will
complete lists of these values separated by commas.
Like _arguments, this function temporarily adds another context
name component to the arguments element (the fifth) of the cur-
rent context while executing the action. Here this name is just
the name of the value for which the argument is completed.
The style verbose is used to decide if the descriptions for the
values (but not those for the arguments) should be printed.
The associative array val_args is used to report values and their
arguments; this works similarly to the opt_args associative array
used by _arguments. Hence the function calling _values should
declare the local parameters state, state_descr, line, context
and val_args:
local context state state_descr line
typeset -A val_args
when using an action of the form `->string'. With this function
the context parameter will be set to the name of the value whose
argument is to be completed. Note that for _values, the state
and state_descr are scalars rather than arrays. Only a single
matching state is returned.
Note also that _values normally adds the character used as the
separator between values as an auto-removable suffix (similar to
a `/' after a directory). However, this is not possible for a
`->string' action as the matches for the argument are generated
by the calling function. To get the usual behaviour, the calling
function can add the separator x as a suffix by passing the op-
tions `-qS x' either directly or indirectly to compadd.
The option -C is treated in the same way as it is by _arguments.
In that case the parameter curcontext should be made local in-
stead of context (as described above).
_wanted [ -x ] [ -C name ] [ -12VJ ] tag name descr command [ arg ...]
In many contexts, completion can only generate one particular set
of matches, usually corresponding to a single tag. However, it
is still necessary to decide whether the user requires matches of
this type. This function is useful in such a case.
The arguments to _wanted are the same as those to _requested,
i.e. arguments to be passed to _description. However, in this
case the command is not optional; all the processing of tags,
including the loop over both tags and tag labels and the genera-
tion of matches, is carried out automatically by _wanted.
Hence to offer only one tag and immediately add the corresponding
matches with the given description:
local expl
_wanted tag expl 'description' \
compadd -- match1 match2...
See also the use of _wanted in the example function in the sub-
section `Dynamic named directories' in zshexpn(1).
Note that, as for _requested, the command must be able to accept
options to be passed down to compadd.
Like _tags this function supports the -C option to give a differ-
ent name for the argument context field. The -x option has the
same meaning as for _description.
_widgets [ -g pattern ]
This function completes names of zle widgets (see the section
`Widgets' in zshzle(1)). The pattern, if present, is matched
against values of the $widgets special parameter, documented in
the section `The zsh/zleparameter Module' in zshmodules(1).
COMPLETION SYSTEM VARIABLES
There are some standard variables, initialised by the _main_complete
function and then used from other functions.
The standard variables are:
_comp_caller_options
The completion system uses setopt to set a number of options.
This allows functions to be written without concern for compati-
bility with every possible combination of user options. However,
sometimes completion needs to know what the user's option prefer-
ences are. These are saved in the _comp_caller_options associa-
tive array. Option names, spelled in lowercase without under-
scores, are mapped to one or other of the strings `on' and `off'.
_comp_priv_prefix
Completion functions such as _sudo can set the _comp_priv_prefix
array to a command prefix that may then be used by _call_program
to match the privileges when calling programs to generate
matches.
Two more features are offered by the _main_complete function. The ar-
rays compprefuncs and comppostfuncs may contain names of functions that
are to be called immediately before or after completion has been tried.
A function will only be called once unless it explicitly reinserts it-
self into the array.
COMPLETION DIRECTORIES
In the source distribution, the files are contained in various subdirec-
tories of the Completion directory. They may have been installed in the
same structure, or into one single function directory. The following is
a description of the files found in the original directory structure.
If you wish to alter an installed file, you will need to copy it to some
directory which appears earlier in your fpath than the standard direc-
tory where it appears.
Base The core functions and special completion widgets automatically
bound to keys. You will certainly need most of these, though
will probably not need to alter them. Many of these are docu-
mented above.
Zsh Functions for completing arguments of shell builtin commands and
utility functions for this. Some of these are also used by func-
tions from the Unix directory.
Unix Functions for completing arguments of external commands and
suites of commands. They may need modifying for your system, al-
though in many cases some attempt is made to decide which version
of a command is present. For example, completion for the mount
command tries to determine the system it is running on, while
completion for many other utilities try to decide whether the GNU
version of the command is in use, and hence whether the --help
option is supported.
X, AIX, BSD, ...
Completion and utility function for commands available only on
some systems. These are not arranged hierarchically, so, for ex-
ample, both the Linux and Debian directories, as well as the X
directory, may be useful on your system.
zsh 5.9 May 14, 2022 ZSHCOMPSYS(1)
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