ZSHPARAM(1) General Commands Manual ZSHPARAM(1)
NAME
zshparam - zsh parameters
DESCRIPTION
A parameter has a name, a value, and a number of attributes. A name may
be any sequence of alphanumeric characters and underscores, or the sin-
gle characters `*', `@', `#', `?', `-', `$', or `!'. A parameter whose
name begins with an alphanumeric or underscore is also referred to as a
variable.
The attributes of a parameter determine the type of its value, often re-
ferred to as the parameter type or variable type, and also control other
processing that may be applied to the value when it is referenced. The
value type may be a scalar (a string, an integer, or a floating point
number), an array (indexed numerically), or an associative array (an un-
ordered set of name-value pairs, indexed by name, also referred to as a
hash).
Named scalar parameters may have the exported, -x, attribute, to copy
them into the process environment, which is then passed from the shell
to any new processes that it starts. Exported parameters are called en-
vironment variables. The shell also imports environment variables at
startup time and automatically marks the corresponding parameters as ex-
ported. Some environment variables are not imported for reasons of se-
curity or because they would interfere with the correct operation of
other shell features.
Parameters may also be special, that is, they have a predetermined mean-
ing to the shell. Special parameters cannot have their type changed or
their readonly attribute turned off, and if a special parameter is un-
set, then later recreated, the special properties will be retained.
To declare the type of a parameter, or to assign a string or numeric
value to a scalar parameter, use the typeset builtin.
The value of a scalar parameter may also be assigned by writing:
name=value
In scalar assignment, value is expanded as a single string, in which the
elements of arrays are joined together; filename expansion is not per-
formed unless the option GLOB_ASSIGN is set.
When the integer attribute, -i, or a floating point attribute, -E or -F,
is set for name, the value is subject to arithmetic evaluation. Fur-
thermore, by replacing `=' with `+=', a parameter can be incremented or
appended to. See the section `Array Parameters' and Arithmetic Evalua-
tion (in zshmisc(1)) for additional forms of assignment.
Note that assignment may implicitly change the attributes of a parame-
ter. For example, assigning a number to a variable in arithmetic evalu-
ation may change its type to integer or float, and with GLOB_ASSIGN as-
signing a pattern to a variable may change its type to an array.
To reference the value of a parameter, write `$name' or `${name}'. See
Parameter Expansion in zshexpn(1) for complete details. That section
also explains the effect of the difference between scalar and array as-
signment on parameter expansion.
ARRAY PARAMETERS
To assign an array value, write one of:
set -A name value ...
name=(value ...)
name=([key]=value ...)
If no parameter name exists, an ordinary array parameter is created. If
the parameter name exists and is a scalar, it is replaced by a new ar-
ray.
In the third form, key is an expression that will be evaluated in arith-
metic context (in its simplest form, an integer) that gives the index of
the element to be assigned with value. In this form any elements not
explicitly mentioned that come before the largest index to which a value
is assigned are assigned an empty string. The indices may be in any or-
der. Note that this syntax is strict: [ and ]= must not be quoted, and
key may not consist of the unquoted string ]=, but is otherwise treated
as a simple string. The enhanced forms of subscript expression that may
be used when directly subscripting a variable name, described in the
section `Array Subscripts' below, are not available.
The syntaxes with and without the explicit key may be mixed. An im-
plicit key is deduced by incrementing the index from the previously as-
signed element. Note that it is not treated as an error if latter as-
signments in this form overwrite earlier assignments.
For example, assuming the option KSH_ARRAYS is not set, the following:
array=(one [3]=three four)
causes the array variable array to contain four elements one, an empty
string, three and four, in that order.
In the forms where only value is specified, full command line expansion
is performed.
In the [key]=value form, both key and value undergo all forms of expan-
sion allowed for single word shell expansions (this does not include
filename generation); these are as performed by the parameter expansion
flag (e) as described in zshexpn(1). Nested parentheses may surround
value and are included as part of the value, which is joined into a
plain string; this differs from ksh which allows the values themselves
to be arrays. A future version of zsh may support that. To cause the
brackets to be interpreted as a character class for filename generation,
and therefore to treat the resulting list of files as a set of values,
quote the equal sign using any form of quoting. Example:
name=([a-z]'='*)
To append to an array without changing the existing values, use one of
the following:
name+=(value ...)
name+=([key]=value ...)
In the second form key may specify an existing index as well as an index
off the end of the old array; any existing value is overwritten by
value. Also, it is possible to use [key]+=value to append to the exist-
ing value at that index.
Within the parentheses on the right hand side of either form of the as-
signment, newlines and semicolons are treated the same as white space,
separating individual values. Any consecutive sequence of such charac-
ters has the same effect.
Ordinary array parameters may also be explicitly declared with:
typeset -a name
Associative arrays must be declared before assignment, by using:
typeset -A name
When name refers to an associative array, the list in an assignment is
interpreted as alternating keys and values:
set -A name key value ...
name=(key value ...)
name=([key]=value ...)
Note that only one of the two syntaxes above may be used in any given
assignment; the forms may not be mixed. This is unlike the case of nu-
merically indexed arrays.
Every key must have a value in this case. Note that this assigns to the
entire array, deleting any elements that do not appear in the list. The
append syntax may also be used with an associative array:
name+=(key value ...)
name+=([key]=value ...)
This adds a new key/value pair if the key is not already present, and
replaces the value for the existing key if it is. In the second form it
is also possible to use [key]+=value to append to the existing value at
that key. Expansion is performed identically to the corresponding forms
for normal arrays, as described above.
To create an empty array (including associative arrays), use one of:
set -A name
name=()
Array Subscripts
Individual elements of an array may be selected using a subscript. A
subscript of the form `[exp]' selects the single element exp, where exp
is an arithmetic expression which will be subject to arithmetic expan-
sion as if it were surrounded by `$((...))'. The elements are numbered
beginning with 1, unless the KSH_ARRAYS option is set in which case they
are numbered from zero.
Subscripts may be used inside braces used to delimit a parameter name,
thus `${foo[2]}' is equivalent to `$foo[2]'. If the KSH_ARRAYS option
is set, the braced form is the only one that works, as bracketed expres-
sions otherwise are not treated as subscripts.
If the KSH_ARRAYS option is not set, then by default accesses to an ar-
ray element with a subscript that evaluates to zero return an empty
string, while an attempt to write such an element is treated as an er-
ror. For backward compatibility the KSH_ZERO_SUBSCRIPT option can be
set to cause subscript values 0 and 1 to be equivalent; see the descrip-
tion of the option in zshoptions(1).
The same subscripting syntax is used for associative arrays, except that
no arithmetic expansion is applied to exp. However, the parsing rules
for arithmetic expressions still apply, which affects the way that cer-
tain special characters must be protected from interpretation. See Sub-
script Parsing below for details.
A subscript of the form `[*]' or `[@]' evaluates to all elements of an
array; there is no difference between the two except when they appear
within double quotes. `"$foo[*]"' evaluates to `"$foo[1] $foo[2] ..."',
whereas `"$foo[@]"' evaluates to `"$foo[1]" "$foo[2]" ...'. For asso-
ciative arrays, `[*]' or `[@]' evaluate to all the values, in no partic-
ular order. Note that this does not substitute the keys; see the docu-
mentation for the `k' flag under Parameter Expansion Flags in zshexpn(1)
for complete details. When an array parameter is referenced as `$name'
(with no subscript) it evaluates to `$name[*]', unless the KSH_ARRAYS
option is set in which case it evaluates to `${name[0]}' (for an asso-
ciative array, this means the value of the key `0', which may not exist
even if there are values for other keys).
A subscript of the form `[exp1,exp2]' selects all elements in the range
exp1 to exp2, inclusive. (Associative arrays are unordered, and so do
not support ranges.) If one of the subscripts evaluates to a negative
number, say -n, then the nth element from the end of the array is used.
Thus `$foo[-3]' is the third element from the end of the array foo, and
`$foo[1,-1]' is the same as `$foo[*]'.
Subscripting may also be performed on non-array values, in which case
the subscripts specify a substring to be extracted. For example, if FOO
is set to `foobar', then `echo $FOO[2,5]' prints `ooba'. Note that some
forms of subscripting described below perform pattern matching, and in
that case the substring extends from the start of the match of the first
subscript to the end of the match of the second subscript. For example,
string="abcdefghijklm"
print ${string[(r)d?,(r)h?]}
prints `defghi'. This is an obvious generalisation of the rule for sin-
gle-character matches. For a single subscript, only a single character
is referenced (not the range of characters covered by the match).
Note that in substring operations the second subscript is handled dif-
ferently by the r and R subscript flags: the former takes the shortest
match as the length and the latter the longest match. Hence in the for-
mer case a * at the end is redundant while in the latter case it matches
the whole remainder of the string. This does not affect the result of
the single subscript case as here the length of the match is irrelevant.
Array Element Assignment
A subscript may be used on the left side of an assignment like so:
name[exp]=value
In this form of assignment the element or range specified by exp is re-
placed by the expression on the right side. An array (but not an asso-
ciative array) may be created by assignment to a range or element. Ar-
rays do not nest, so assigning a parenthesized list of values to an ele-
ment or range changes the number of elements in the array, shifting the
other elements to accommodate the new values. (This is not supported
for associative arrays.)
This syntax also works as an argument to the typeset command:
typeset "name[exp]"=value
The value may not be a parenthesized list in this case; only single-ele-
ment assignments may be made with typeset. Note that quotes are neces-
sary in this case to prevent the brackets from being interpreted as
filename generation operators. The noglob precommand modifier could be
used instead.
To delete an element of an ordinary array, assign `()' to that element.
To delete an element of an associative array, use the unset command:
unset "name[exp]"
Subscript Flags
If the opening bracket, or the comma in a range, in any subscript ex-
pression is directly followed by an opening parenthesis, the string up
to the matching closing one is considered to be a list of flags, as in
`name[(flags)exp]'.
The flags s, n and b take an argument; the delimiter is shown below as
`:', but any character, or the matching pairs `(...)', `{...}', `[...]',
or `<...>', may be used, but note that `<...>' can only be used if the
subscript is inside a double quoted expression or a parameter substitu-
tion enclosed in braces as otherwise the expression is interpreted as a
redirection.
The flags currently understood are:
w If the parameter subscripted is a scalar then this flag makes
subscripting work on words instead of characters. The default
word separator is whitespace. When combined with the i or I
flag, the effect is to produce the index of the first character
of the first/last word which matches the given pattern; note that
a failed match in this case always yields 0.
s:string:
This gives the string that separates words (for use with the w
flag). The delimiter character : is arbitrary; see above.
p Recognize the same escape sequences as the print builtin in the
string argument of a subsequent `s' flag.
f If the parameter subscripted is a scalar then this flag makes
subscripting work on lines instead of characters, i.e. with ele-
ments separated by newlines. This is a shorthand for `pws:\n:'.
r Reverse subscripting: if this flag is given, the exp is taken as
a pattern and the result is the first matching array element,
substring or word (if the parameter is an array, if it is a
scalar, or if it is a scalar and the `w' flag is given, respec-
tively). The subscript used is the number of the matching ele-
ment, so that pairs of subscripts such as `$foo[(r)??,3]' and
`$foo[(r)??,(r)f*]' are possible if the parameter is not an asso-
ciative array. If the parameter is an associative array, only
the value part of each pair is compared to the pattern, and the
result is that value.
If a search through an ordinary array failed, the search sets the
subscript to one past the end of the array, and hence ${ar-
ray[(r)pattern]} will substitute the empty string. Thus the suc-
cess of a search can be tested by using the (i) flag, for example
(assuming the option KSH_ARRAYS is not in effect):
[[ ${array[(i)pattern]} -le ${#array} ]]
If KSH_ARRAYS is in effect, the -le should be replaced by -lt.
R Like `r', but gives the last match. For associative arrays,
gives all possible matches. May be used for assigning to ordinary
array elements, but not for assigning to associative arrays. On
failure, for normal arrays this has the effect of returning the
element corresponding to subscript 0; this is empty unless one of
the options KSH_ARRAYS or KSH_ZERO_SUBSCRIPT is in effect.
Note that in subscripts with both `r' and `R' pattern characters
are active even if they were substituted for a parameter (regard-
less of the setting of GLOB_SUBST which controls this feature in
normal pattern matching). The flag `e' can be added to inhibit
pattern matching. As this flag does not inhibit other forms of
substitution, care is still required; using a parameter to hold
the key has the desired effect:
key2='original key'
print ${array[(Re)$key2]}
i Like `r', but gives the index of the match instead; this may not
be combined with a second argument. On the left side of an as-
signment, behaves like `r'. For associative arrays, the key part
of each pair is compared to the pattern, and the first matching
key found is the result. On failure substitutes the length of
the array plus one, as discussed under the description of `r', or
the empty string for an associative array.
Note: Although `i' may be applied to a scalar substitution to
find the offset of a substring, the results are likely to be mis-
leading when searching within substitutions that yield an empty
string, or when searching for the empty substring.
I Like `i', but gives the index of the last match, or all possible
matching keys in an associative array. On failure substitutes 0,
or the empty string for an associative array. This flag is best
when testing for values or keys that do not exist.
Note: If the option KSH_ARRAYS is in effect and no match is
found, the result is indistinguishable from the case when the
first element of the array matches.
k If used in a subscript on an associative array, this flag causes
the keys to be interpreted as patterns, and returns the value for
the first key found where exp is matched by the key. Note this
could be any such key as no ordering of associative arrays is de-
fined. This flag does not work on the left side of an assignment
to an associative array element. If used on another type of pa-
rameter, this behaves like `r'.
K On an associative array this is like `k' but returns all values
where exp is matched by the keys. On other types of parameters
this has the same effect as `R'.
n:expr:
If combined with `r', `R', `i' or `I', makes them give the nth or
nth last match (if expr evaluates to n). This flag is ignored
when the array is associative. The delimiter character : is ar-
bitrary; see above.
b:expr:
If combined with `r', `R', `i' or `I', makes them begin at the
nth or nth last element, word, or character (if expr evaluates to
n). This flag is ignored when the array is associative. The de-
limiter character : is arbitrary; see above.
e This flag causes any pattern matching that would be performed on
the subscript to use plain string matching instead. Hence `${ar-
ray[(re)*]}' matches only the array element whose value is *.
Note that other forms of substitution such as parameter substitu-
tion are not inhibited.
This flag can also be used to force * or @ to be interpreted as a
single key rather than as a reference to all values. It may be
used for either purpose on the left side of an assignment.
See Parameter Expansion Flags (zshexpn(1)) for additional ways to manip-
ulate the results of array subscripting.
Subscript Parsing
This discussion applies mainly to associative array key strings and to
patterns used for reverse subscripting (the `r', `R', `i', etc. flags),
but it may also affect parameter substitutions that appear as part of an
arithmetic expression in an ordinary subscript.
To avoid subscript parsing limitations in assignments to associative ar-
ray elements, use the append syntax:
aa+=('key with "*strange*" characters' 'value string')
The basic rule to remember when writing a subscript expression is that
all text between the opening `[' and the closing `]' is interpreted as
if it were in double quotes (see zshmisc(1)). However, unlike double
quotes which normally cannot nest, subscript expressions may appear in-
side double-quoted strings or inside other subscript expressions (or
both!), so the rules have two important differences.
The first difference is that brackets (`[' and `]') must appear as bal-
anced pairs in a subscript expression unless they are preceded by a
backslash (`\'). Therefore, within a subscript expression (and unlike
true double-quoting) the sequence `\[' becomes `[', and similarly `\]'
becomes `]'. This applies even in cases where a backslash is not nor-
mally required; for example, the pattern `[^[]' (to match any character
other than an open bracket) should be written `[^\[]' in a reverse-sub-
script pattern. However, note that `\[^\[\]' and even `\[^[]' mean the
same thing, because backslashes are always stripped when they appear be-
fore brackets!
The same rule applies to parentheses (`(' and `)') and braces (`{' and
`}'): they must appear either in balanced pairs or preceded by a back-
slash, and backslashes that protect parentheses or braces are removed
during parsing. This is because parameter expansions may be surrounded
by balanced braces, and subscript flags are introduced by balanced
parentheses.
The second difference is that a double-quote (`"') may appear as part of
a subscript expression without being preceded by a backslash, and there-
fore that the two characters `\"' remain as two characters in the sub-
script (in true double-quoting, `\"' becomes `"'). However, because of
the standard shell quoting rules, any double-quotes that appear must oc-
cur in balanced pairs unless preceded by a backslash. This makes it
more difficult to write a subscript expression that contains an odd num-
ber of double-quote characters, but the reason for this difference is so
that when a subscript expression appears inside true double-quotes, one
can still write `\"' (rather than `\\\"') for `"'.
To use an odd number of double quotes as a key in an assignment, use the
typeset builtin and an enclosing pair of double quotes; to refer to the
value of that key, again use double quotes:
typeset -A aa
typeset "aa[one\"two\"three\"quotes]"=QQQ
print "$aa[one\"two\"three\"quotes]"
It is important to note that the quoting rules do not change when a pa-
rameter expansion with a subscript is nested inside another subscript
expression. That is, it is not necessary to use additional backslashes
within the inner subscript expression; they are removed only once, from
the innermost subscript outwards. Parameters are also expanded from the
innermost subscript first, as each expansion is encountered left to
right in the outer expression.
A further complication arises from a way in which subscript parsing is
not different from double quote parsing. As in true double-quoting, the
sequences `\*', and `\@' remain as two characters when they appear in a
subscript expression. To use a literal `*' or `@' as an associative ar-
ray key, the `e' flag must be used:
typeset -A aa
aa[(e)*]=star
print $aa[(e)*]
A last detail must be considered when reverse subscripting is performed.
Parameters appearing in the subscript expression are first expanded and
then the complete expression is interpreted as a pattern. This has two
effects: first, parameters behave as if GLOB_SUBST were on (and it can-
not be turned off); second, backslashes are interpreted twice, once when
parsing the array subscript and again when parsing the pattern. In a
reverse subscript, it's necessary to use four backslashes to cause a
single backslash to match literally in the pattern. For complex pat-
terns, it is often easiest to assign the desired pattern to a parameter
and then refer to that parameter in the subscript, because then the
backslashes, brackets, parentheses, etc., are seen only when the com-
plete expression is converted to a pattern. To match the value of a pa-
rameter literally in a reverse subscript, rather than as a pattern, use
`${(q)name}' (see zshexpn(1)) to quote the expanded value.
Note that the `k' and `K' flags are reverse subscripting for an ordinary
array, but are not reverse subscripting for an associative array! (For
an associative array, the keys in the array itself are interpreted as
patterns by those flags; the subscript is a plain string in that case.)
One final note, not directly related to subscripting: the numeric names
of positional parameters (described below) are parsed specially, so for
example `$2foo' is equivalent to `${2}foo'. Therefore, to use subscript
syntax to extract a substring from a positional parameter, the expansion
must be surrounded by braces; for example, `${2[3,5]}' evaluates to the
third through fifth characters of the second positional parameter, but
`$2[3,5]' is the entire second parameter concatenated with the filename
generation pattern `[3,5]'.
POSITIONAL PARAMETERS
The positional parameters provide access to the command-line arguments
of a shell function, shell script, or the shell itself; see the section
`Invocation', and also the section `Functions'. The parameter n, where
n is a number, is the nth positional parameter. The parameter `$0' is a
special case, see the section `Parameters Set By The Shell'.
The parameters *, @ and argv are arrays containing all the positional
parameters; thus `$argv[n]', etc., is equivalent to simply `$n'. Note
that the options KSH_ARRAYS or KSH_ZERO_SUBSCRIPT apply to these arrays
as well, so with either of those options set, `${argv[0]}' is equivalent
to `$1' and so on.
Positional parameters may be changed after the shell or function starts
by using the set builtin, by assigning to the argv array, or by direct
assignment of the form `n=value' where n is the number of the positional
parameter to be changed. This also creates (with empty values) any of
the positions from 1 to n that do not already have values. Note that,
because the positional parameters form an array, an array assignment of
the form `n=(value ...)' is allowed, and has the effect of shifting all
the values at positions greater than n by as many positions as necessary
to accommodate the new values.
LOCAL PARAMETERS
Shell function executions delimit scopes for shell parameters. (Parame-
ters are dynamically scoped.) The typeset builtin, and its alternative
forms declare, integer, local and readonly (but not export), can be used
to declare a parameter as being local to the innermost scope.
When a parameter is read or assigned to, the innermost existing parame-
ter of that name is used. (That is, the local parameter hides any
less-local parameter.) However, assigning to a non-existent parameter,
or declaring a new parameter with export, causes it to be created in the
outermost scope.
Local parameters disappear when their scope ends. unset can be used to
delete a parameter while it is still in scope; any outer parameter of
the same name remains hidden.
Special parameters may also be made local; they retain their special at-
tributes unless either the existing or the newly-created parameter has
the -h (hide) attribute. This may have unexpected effects: there is no
default value, so if there is no assignment at the point the variable is
made local, it will be set to an empty value (or zero in the case of in-
tegers). The following:
typeset PATH=/new/directory:$PATH
is valid for temporarily allowing the shell or programmes called from it
to find the programs in /new/directory inside a function.
Note that the restriction in older versions of zsh that local parameters
were never exported has been removed.
PARAMETERS SET BY THE SHELL
In the parameter lists that follow, the mark `<S>' indicates that the
parameter is special. `<Z>' indicates that the parameter does not exist
when the shell initializes in sh or ksh emulation mode.
The parameters `!', `#', `*', `-', `?', `@', `$', `ARGC', `HISTCMD',
`LINENO', `PPID', `status', `TTYIDLE', `zsh_eval_context',
`ZSH_EVAL_CONTEXT', and `ZSH_SUBSHELL' are read-only and thus cannot be
restored by the user, so they are not output by `typeset -p'. This also
applies to many read-only parameters loaded from modules.
The following parameters are automatically set by the shell:
! <S> The process ID of the last command started in the background with
&, put into the background with the bg builtin, or spawned with
coproc.
# <S> The number of positional parameters in decimal. Note that some
confusion may occur with the syntax $#param which substitutes the
length of param. Use ${#} to resolve ambiguities. In particu-
lar, the sequence `$#-...' in an arithmetic expression is inter-
preted as the length of the parameter -, q.v.
ARGC <S> <Z>
Same as #.
$ <S> The process ID of this shell, set when the shell initializes.
Processes forked from the shell without executing a new program,
such as command substitutions and commands grouped with (...),
are subshells that duplicate the current shell, and thus substi-
tute the same value for $$ as their parent shell.
- <S> Flags supplied to the shell on invocation or by the set or setopt
commands.
* <S> An array containing the positional parameters.
argv <S> <Z>
Same as *. Assigning to argv changes the local positional para-
meters, but argv is not itself a local parameter. Deleting argv
with unset in any function deletes it everywhere, although only
the innermost positional parameter array is deleted (so * and @
in other scopes are not affected).
@ <S> Same as argv[@], even when argv is not set.
? <S> The exit status returned by the last command.
0 <S> The name used to invoke the current shell, or as set by the -c
command line option upon invocation. If the FUNCTION_ARGZERO op-
tion is set, $0 is set upon entry to a shell function to the name
of the function, and upon entry to a sourced script to the name
of the script, and reset to its previous value when the function
or script returns.
status <S> <Z>
Same as ?.
pipestatus <S> <Z>
An array containing the exit statuses returned by all commands in
the last pipeline.
_ <S> The last argument of the previous command. Also, this parameter
is set in the environment of every command executed to the full
pathname of the command.
CPUTYPE
The machine type (microprocessor class or machine model), as de-
termined at run time.
EGID <S>
The effective group ID of the shell process. If you have suffi-
cient privileges, you may change the effective group ID of the
shell process by assigning to this parameter. Also (assuming
sufficient privileges), you may start a single command with a
different effective group ID by `(EGID=gid; command)'
If this is made local, it is not implicitly set to 0, but may be
explicitly set locally.
EUID <S>
The effective user ID of the shell process. If you have suffi-
cient privileges, you may change the effective user ID of the
shell process by assigning to this parameter. Also (assuming
sufficient privileges), you may start a single command with a
different effective user ID by `(EUID=uid; command)'
If this is made local, it is not implicitly set to 0, but may be
explicitly set locally.
ERRNO <S>
The value of errno (see errno(3)) as set by the most recently
failed system call. This value is system dependent and is in-
tended for debugging purposes. It is also useful with the
zsh/system module which allows the number to be turned into a
name or message.
To use this parameter, it must first be assigned a value (typi-
cally 0 (zero)). It is initially unset for scripting compatibil-
ity.
FUNCNEST <S>
Integer. If greater than or equal to zero, the maximum nesting
depth of shell functions. When it is exceeded, an error is
raised at the point where a function is called. The default
value is determined when the shell is configured, but is typi-
cally 500. Increasing the value increases the danger of a run-
away function recursion causing the shell to crash. Setting a
negative value turns off the check.
GID <S>
The real group ID of the shell process. If you have sufficient
privileges, you may change the group ID of the shell process by
assigning to this parameter. Also (assuming sufficient privi-
leges), you may start a single command under a different group ID
by `(GID=gid; command)'
If this is made local, it is not implicitly set to 0, but may be
explicitly set locally.
HISTCMD
The current history event number in an interactive shell, in
other words the event number for the command that caused $HISTCMD
to be read. If the current history event modifies the history,
HISTCMD changes to the new maximum history event number.
HOST The current hostname.
LINENO <S>
The line number of the current line within the current script,
sourced file, or shell function being executed, whichever was
started most recently. Note that in the case of shell functions
the line number refers to the function as it appeared in the
original definition, not necessarily as displayed by the func-
tions builtin.
LOGNAME
If the corresponding variable is not set in the environment of
the shell, it is initialized to the login name corresponding to
the current login session. This parameter is exported by default
but this can be disabled using the typeset builtin. The value is
set to the string returned by the getlogin(3) system call if that
is available.
MACHTYPE
The machine type (microprocessor class or machine model), as de-
termined at compile time.
OLDPWD The previous working directory. This is set when the shell ini-
tializes and whenever the directory changes.
OPTARG <S>
The value of the last option argument processed by the getopts
command.
OPTIND <S>
The index of the last option argument processed by the getopts
command.
OSTYPE The operating system, as determined at compile time.
PPID <S>
The process ID of the parent of the shell, set when the shell
initializes. As with $$, the value does not change in subshells
created as a duplicate of the current shell.
PWD The present working directory. This is set when the shell ini-
tializes and whenever the directory changes.
RANDOM <S>
A pseudo-random integer from 0 to 32767, newly generated each
time this parameter is referenced. The random number generator
can be seeded by assigning a numeric value to RANDOM.
The values of RANDOM form an intentionally-repeatable pseudo-ran-
dom sequence; subshells that reference RANDOM will result in
identical pseudo-random values unless the value of RANDOM is ref-
erenced or seeded in the parent shell in between subshell invoca-
tions.
SECONDS <S>
The number of seconds since shell invocation. If this parameter
is assigned a value, then the value returned upon reference will
be the value that was assigned plus the number of seconds since
the assignment.
Unlike other special parameters, the type of the SECONDS parame-
ter can be changed using the typeset command. The type may be
changed only to one of the floating point types or back to inte-
ger. For example, `typeset -F SECONDS' causes the value to be
reported as a floating point number. The value is available to
microsecond accuracy, although the shell may show more or fewer
digits depending on the use of typeset. See the documentation
for the builtin typeset in zshbuiltins(1) for more details.
SHLVL <S>
Incremented by one each time a new shell is started.
signals
An array containing the names of the signals. Note that with the
standard zsh numbering of array indices, where the first element
has index 1, the signals are offset by 1 from the signal number
used by the operating system. For example, on typical Unix-like
systems HUP is signal number 1, but is referred to as $sig-
nals[2]. This is because of EXIT at position 1 in the array,
which is used internally by zsh but is not known to the operating
system.
TRY_BLOCK_ERROR <S>
In an always block, indicates whether the preceding list of code
caused an error. The value is 1 to indicate an error, 0 other-
wise. It may be reset, clearing the error condition. See Com-
plex Commands in zshmisc(1)
TRY_BLOCK_INTERRUPT <S>
This variable works in a similar way to TRY_BLOCK_ERROR, but rep-
resents the status of an interrupt from the signal SIGINT, which
typically comes from the keyboard when the user types ^C. If set
to 0, any such interrupt will be reset; otherwise, the interrupt
is propagated after the always block.
Note that it is possible that an interrupt arrives during the ex-
ecution of the always block; this interrupt is also propagated.
TTY The name of the tty associated with the shell, if any.
TTYIDLE <S>
The idle time of the tty associated with the shell in seconds or
-1 if there is no such tty.
UID <S>
The real user ID of the shell process. If you have sufficient
privileges, you may change the user ID of the shell by assigning
to this parameter. Also (assuming sufficient privileges), you
may start a single command under a different user ID by
`(UID=uid; command)'
If this is made local, it is not implicitly set to 0, but may be
explicitly set locally.
USERNAME <S>
The username corresponding to the real user ID of the shell
process. If you have sufficient privileges, you may change the
username (and also the user ID and group ID) of the shell by as-
signing to this parameter. Also (assuming sufficient privi-
leges), you may start a single command under a different username
(and user ID and group ID) by `(USERNAME=username; command)'
VENDOR The vendor, as determined at compile time.
zsh_eval_context <S> <Z> (ZSH_EVAL_CONTEXT <S>)
An array (colon-separated list) indicating the context of shell
code that is being run. Each time a piece of shell code that is
stored within the shell is executed a string is temporarily ap-
pended to the array to indicate the type of operation that is be-
ing performed. Read in order the array gives an indication of
the stack of operations being performed with the most immediate
context last.
Note that the variable does not give information on syntactic
context such as pipelines or subshells. Use $ZSH_SUBSHELL to de-
tect subshells.
The context is one of the following:
cmdarg Code specified by the -c option to the command line that
invoked the shell.
cmdsubst
Command substitution using the `...` or $(...) construct.
equalsubst
File substitution using the =(...) construct.
eval Code executed by the eval builtin.
evalautofunc
Code executed with the KSH_AUTOLOAD mechanism in order to
define an autoloaded function.
fc Code from the shell history executed by the -e option to
the fc builtin.
file Lines of code being read directly from a file, for example
by the source builtin.
filecode
Lines of code being read from a .zwc file instead of di-
rectly from the source file.
globqual
Code executed by the e or + glob qualifier.
globsort
Code executed to order files by the o glob qualifier.
insubst
File substitution using the <(...) construct.
loadautofunc
Code read directly from a file to define an autoloaded
function.
outsubst
File substitution using the >(...) construct.
sched Code executed by the sched builtin.
shfunc A shell function.
stty Code passed to stty by the STTY environment variable.
Normally this is passed directly to the system's stty com-
mand, so this value is unlikely to be seen in practice.
style Code executed as part of a style retrieved by the zstyle
builtin from the zsh/zutil module.
toplevel
The highest execution level of a script or interactive
shell.
trap Code executed as a trap defined by the trap builtin.
Traps defined as functions have the context shfunc. As
traps are asynchronous they may have a different hierarchy
from other code.
zpty Code executed by the zpty builtin from the zsh/zpty mod-
ule.
zregexparse-guard
Code executed as a guard by the zregexparse command from
the zsh/zutil module.
zregexparse-action
Code executed as an action by the zregexparse command from
the zsh/zutil module.
ZSH_ARGZERO
If zsh was invoked to run a script, this is the name of the
script. Otherwise, it is the name used to invoke the current
shell. This is the same as the value of $0 when the
POSIX_ARGZERO option is set, but is always available.
ZSH_EXECUTION_STRING
If the shell was started with the option -c, this contains the
argument passed to the option. Otherwise it is not set.
ZSH_NAME
Expands to the basename of the command used to invoke this in-
stance of zsh.
ZSH_PATCHLEVEL
The output of `git describe --tags --long' for the zsh repository
used to build the shell. This is most useful in order to keep
track of versions of the shell during development between re-
leases; hence most users should not use it and should instead
rely on $ZSH_VERSION.
zsh_scheduled_events
See the section `The zsh/sched Module' in zshmodules(1).
ZSH_SCRIPT
If zsh was invoked to run a script, this is the name of the
script, otherwise it is unset.
ZSH_SUBSHELL
Readonly integer. Initially zero, incremented each time the
shell forks to create a subshell for executing code. Hence
`(print $ZSH_SUBSHELL)' and `print $(print $ZSH_SUBSHELL)' output
1, while `( (print $ZSH_SUBSHELL) )' outputs 2.
ZSH_VERSION
The version number of the release of zsh.
PARAMETERS USED BY THE SHELL
The following parameters are used by the shell. Again, `<S>' indicates
that the parameter is special and `<Z>' indicates that the parameter
does not exist when the shell initializes in sh or ksh emulation mode.
In cases where there are two parameters with an upper- and lowercase
form of the same name, such as path and PATH, the lowercase form is an
array and the uppercase form is a scalar with the elements of the array
joined together by colons. These are similar to tied parameters created
via `typeset -T'. The normal use for the colon-separated form is for
exporting to the environment, while the array form is easier to manipu-
late within the shell. Note that unsetting either of the pair will un-
set the other; they retain their special properties when recreated, and
recreating one of the pair will recreate the other.
ARGV0 If exported, its value is used as the argv[0] of external com-
mands. Usually used in constructs like `ARGV0=emacs nethack'.
BAUD The rate in bits per second at which data reaches the terminal.
The line editor will use this value in order to compensate for a
slow terminal by delaying updates to the display until necessary.
If the parameter is unset or the value is zero the compensation
mechanism is turned off. The parameter is not set by default.
This parameter may be profitably set in some circumstances, e.g.
for slow modems dialing into a communications server, or on a
slow wide area network. It should be set to the baud rate of the
slowest part of the link for best performance.
cdpath <S> <Z> (CDPATH <S>)
An array (colon-separated list) of directories specifying the
search path for the cd command.
COLUMNS <S>
The number of columns for this terminal session. Used for print-
ing select lists and for the line editor.
CORRECT_IGNORE
If set, is treated as a pattern during spelling correction. Any
potential correction that matches the pattern is ignored. For
example, if the value is `_*' then completion functions (which,
by convention, have names beginning with `_') will never be of-
fered as spelling corrections. The pattern does not apply to the
correction of file names, as applied by the CORRECT_ALL option
(so with the example just given files beginning with `_' in the
current directory would still be completed).
CORRECT_IGNORE_FILE
If set, is treated as a pattern during spelling correction of
file names. Any file name that matches the pattern is never of-
fered as a correction. For example, if the value is `.*' then
dot file names will never be offered as spelling corrections.
This is useful with the CORRECT_ALL option.
DIRSTACKSIZE
The maximum size of the directory stack, by default there is no
limit. If the stack gets larger than this, it will be truncated
automatically. This is useful with the AUTO_PUSHD option.
ENV If the ENV environment variable is set when zsh is invoked as sh
or ksh, $ENV is sourced after the profile scripts. The value of
ENV is subjected to parameter expansion, command substitution,
and arithmetic expansion before being interpreted as a pathname.
Note that ENV is not used unless the shell is interactive and zsh
is emulating sh or ksh.
FCEDIT The default editor for the fc builtin. If FCEDIT is not set, the
parameter EDITOR is used; if that is not set either, a builtin
default, usually vi, is used.
fignore <S> <Z> (FIGNORE <S>)
An array (colon separated list) containing the suffixes of files
to be ignored during filename completion. However, if completion
only generates files with suffixes in this list, then these files
are completed anyway.
fpath <S> <Z> (FPATH <S>)
An array (colon separated list) of directories specifying the
search path for function definitions. This path is searched when
a function with the -u attribute is referenced. If an executable
file is found, then it is read and executed in the current envi-
ronment.
histchars <S>
Three characters used by the shell's history and lexical analysis
mechanism. The first character signals the start of a history
expansion (default `!'). The second character signals the start
of a quick history substitution (default `^'). The third charac-
ter is the comment character (default `#').
The characters must be in the ASCII character set; any attempt to
set histchars to characters with a locale-dependent meaning will
be rejected with an error message.
HISTCHARS <S> <Z>
Same as histchars. (Deprecated.)
HISTFILE
The file to save the history in when an interactive shell exits.
If unset, the history is not saved.
HISTORY_IGNORE
If set, is treated as a pattern at the time history files are
written. Any potential history entry that matches the pattern is
skipped. For example, if the value is `fc *' then commands that
invoke the interactive history editor are never written to the
history file.
Note that HISTORY_IGNORE defines a single pattern: to specify al-
ternatives use the `(first|second|...)' syntax.
Compare the HIST_NO_STORE option or the zshaddhistory hook, ei-
ther of which would prevent such commands from being added to the
interactive history at all. If you wish to use HISTORY_IGNORE to
stop history being added in the first place, you can define the
following hook:
zshaddhistory() {
emulate -L zsh
## uncomment if HISTORY_IGNORE
## should use EXTENDED_GLOB syntax
# setopt extendedglob
[[ $1 != ${~HISTORY_IGNORE} ]]
}
HISTSIZE <S>
The maximum number of events stored in the internal history list.
If you use the HIST_EXPIRE_DUPS_FIRST option, setting this value
larger than the SAVEHIST size will give you the difference as a
cushion for saving duplicated history events.
If this is made local, it is not implicitly set to 0, but may be
explicitly set locally.
HOME <S>
The default argument for the cd command. This is not set auto-
matically by the shell in sh, ksh or csh emulation, but it is
typically present in the environment anyway, and if it becomes
set it has its usual special behaviour.
IFS <S>
Internal field separators (by default space, tab, newline and
NUL), that are used to separate words which result from command
or parameter expansion and words read by the read builtin. Any
characters from the set space, tab and newline that appear in the
IFS are called IFS white space. One or more IFS white space
characters or one non-IFS white space character together with any
adjacent IFS white space character delimit a field. If an IFS
white space character appears twice consecutively in the IFS,
this character is treated as if it were not an IFS white space
character.
If the parameter is unset, the default is used. Note this has a
different effect from setting the parameter to an empty string.
KEYBOARD_HACK
This variable defines a character to be removed from the end of
the command line before interpreting it (interactive shells
only). It is intended to fix the problem with keys placed annoy-
ingly close to return and replaces the SUNKEYBOARDHACK option
which did this for backquotes only. Should the chosen character
be one of singlequote, doublequote or backquote, there must also
be an odd number of them on the command line for the last one to
be removed.
For backward compatibility, if the SUNKEYBOARDHACK option is ex-
plicitly set, the value of KEYBOARD_HACK reverts to backquote.
If the option is explicitly unset, this variable is set to empty.
KEYTIMEOUT
The time the shell waits, in hundredths of seconds, for another
key to be pressed when reading bound multi-character sequences.
LANG <S>
This variable determines the locale category for any category not
specifically selected via a variable starting with `LC_'.
LC_ALL <S>
This variable overrides the value of the `LANG' variable and the
value of any of the other variables starting with `LC_'.
LC_COLLATE <S>
This variable determines the locale category for character colla-
tion information within ranges in glob brackets and for sorting.
LC_CTYPE <S>
This variable determines the locale category for character han-
dling functions. If the MULTIBYTE option is in effect this vari-
able or LANG should contain a value that reflects the character
set in use, even if it is a single-byte character set, unless
only the 7-bit subset (ASCII) is used. For example, if the char-
acter set is ISO-8859-1, a suitable value might be en_US.iso88591
(certain Linux distributions) or en_US.ISO8859-1 (MacOS).
LC_MESSAGES <S>
This variable determines the language in which messages should be
written. Note that zsh does not use message catalogs.
LC_NUMERIC <S>
This variable affects the decimal point character and thousands
separator character for the formatted input/output functions and
string conversion functions. Note that zsh ignores this setting
when parsing floating point mathematical expressions.
LC_TIME <S>
This variable determines the locale category for date and time
formatting in prompt escape sequences.
LINES <S>
The number of lines for this terminal session. Used for printing
select lists and for the line editor.
LISTMAX
In the line editor, the number of matches to list without asking
first. If the value is negative, the list will be shown if it
spans at most as many lines as given by the absolute value. If
set to zero, the shell asks only if the top of the listing would
scroll off the screen.
MAIL If this parameter is set and mailpath is not set, the shell looks
for mail in the specified file.
MAILCHECK
The interval in seconds between checks for new mail.
mailpath <S> <Z> (MAILPATH <S>)
An array (colon-separated list) of filenames to check for new
mail. Each filename can be followed by a `?' and a message that
will be printed. The message will undergo parameter expansion,
command substitution and arithmetic expansion with the variable
$_ defined as the name of the file that has changed. The default
message is `You have new mail'. If an element is a directory in-
stead of a file the shell will recursively check every file in
every subdirectory of the element.
manpath <S> <Z> (MANPATH <S> <Z>)
An array (colon-separated list) whose value is not used by the
shell. The manpath array can be useful, however, since setting
it also sets MANPATH, and vice versa.
match
mbegin
mend Arrays set by the shell when the b globbing flag is used in pat-
tern matches. See the subsection Globbing flags in the documen-
tation for Filename Generation in zshexpn(1).
MATCH
MBEGIN
MEND Set by the shell when the m globbing flag is used in pattern
matches. See the subsection Globbing flags in the documentation
for Filename Generation in zshexpn(1).
module_path <S> <Z> (MODULE_PATH <S>)
An array (colon-separated list) of directories that zmodload
searches for dynamically loadable modules. This is initialized
to a standard pathname, usually `/usr/local/lib/zsh/$ZSH_VER-
SION'. (The `/usr/local/lib' part varies from installation to
installation.) For security reasons, any value set in the envi-
ronment when the shell is started will be ignored.
These parameters only exist if the installation supports dynamic
module loading.
NULLCMD <S>
The command name to assume if a redirection is specified with no
command. Defaults to cat. For sh/ksh behavior, change this to
:. For csh-like behavior, unset this parameter; the shell will
print an error message if null commands are entered.
path <S> <Z> (PATH <S>)
An array (colon-separated list) of directories to search for com-
mands. When this parameter is set, each directory is scanned and
all files found are put in a hash table.
POSTEDIT <S>
This string is output whenever the line editor exits. It usually
contains termcap strings to reset the terminal.
PROMPT <S> <Z>
PROMPT2 <S> <Z>
PROMPT3 <S> <Z>
PROMPT4 <S> <Z>
Same as PS1, PS2, PS3 and PS4, respectively.
prompt <S> <Z>
Same as PS1.
PROMPT_EOL_MARK
When the PROMPT_CR and PROMPT_SP options are set, the
PROMPT_EOL_MARK parameter can be used to customize how the end of
partial lines are shown. This parameter undergoes prompt expan-
sion, with the PROMPT_PERCENT option set. If not set, the de-
fault behavior is equivalent to the value `%B%S%#%s%b'.
PS1 <S>
The primary prompt string, printed before a command is read. It
undergoes a special form of expansion before being displayed; see
EXPANSION OF PROMPT SEQUENCES in zshmisc(1). The default is
`%m%# '.
PS2 <S>
The secondary prompt, printed when the shell needs more informa-
tion to complete a command. It is expanded in the same way as
PS1. The default is `%_> ', which displays any shell constructs
or quotation marks which are currently being processed.
PS3 <S>
Selection prompt used within a select loop. It is expanded in
the same way as PS1. The default is `?# '.
PS4 <S>
The execution trace prompt. Default is `+%N:%i> ', which dis-
plays the name of the current shell structure and the line number
within it. In sh or ksh emulation, the default is `+ '.
psvar <S> <Z> (PSVAR <S>)
An array (colon-separated list) whose elements can be used in
PROMPT strings. Setting psvar also sets PSVAR, and vice versa.
READNULLCMD <S>
The command name to assume if a single input redirection is spec-
ified with no command. Defaults to more.
REPORTMEMORY
If nonnegative, commands whose maximum resident set size (roughly
speaking, main memory usage) in kilobytes is greater than this
value have timing statistics reported. The format used to output
statistics is the value of the TIMEFMT parameter, which is the
same as for the REPORTTIME variable and the time builtin; note
that by default this does not output memory usage. Appending "
max RSS %M" to the value of TIMEFMT causes it to output the value
that triggered the report. If REPORTTIME is also in use, at most
a single report is printed for both triggers. This feature re-
quires the getrusage() system call, commonly supported by modern
Unix-like systems.
REPORTTIME
If nonnegative, commands whose combined user and system execution
times (measured in seconds) are greater than this value have tim-
ing statistics printed for them. Output is suppressed for com-
mands executed within the line editor, including completion; com-
mands explicitly marked with the time keyword still cause the
summary to be printed in this case.
REPLY This parameter is reserved by convention to pass string values
between shell scripts and shell builtins in situations where a
function call or redirection are impossible or undesirable. The
read builtin and the select complex command may set REPLY, and
filename generation both sets and examines its value when evalu-
ating certain expressions. Some modules also employ REPLY for
similar purposes.
reply As REPLY, but for array values rather than strings.
RPROMPT <S>
RPS1 <S>
This prompt is displayed on the right-hand side of the screen
when the primary prompt is being displayed on the left. This
does not work if the SINGLE_LINE_ZLE option is set. It is ex-
panded in the same way as PS1.
RPROMPT2 <S>
RPS2 <S>
This prompt is displayed on the right-hand side of the screen
when the secondary prompt is being displayed on the left. This
does not work if the SINGLE_LINE_ZLE option is set. It is ex-
panded in the same way as PS2.
SAVEHIST
The maximum number of history events to save in the history file.
If this is made local, it is not implicitly set to 0, but may be
explicitly set locally.
SPROMPT <S>
The prompt used for spelling correction. The sequence `%R' ex-
pands to the string which presumably needs spelling correction,
and `%r' expands to the proposed correction. All other prompt
escapes are also allowed.
The actions available at the prompt are [nyae]:
n (`no') (default)
Discard the correction and run the command.
y (`yes')
Make the correction and run the command.
a (`abort')
Discard the entire command line without running it.
e (`edit')
Resume editing the command line.
STTY If this parameter is set in a command's environment, the shell
runs the stty command with the value of this parameter as argu-
ments in order to set up the terminal before executing the com-
mand. The modes apply only to the command, and are reset when it
finishes or is suspended. If the command is suspended and contin-
ued later with the fg or wait builtins it will see the modes
specified by STTY, as if it were not suspended. This (intention-
ally) does not apply if the command is continued via `kill
-CONT'. STTY is ignored if the command is run in the background,
or if it is in the environment of the shell but not explicitly
assigned to in the input line. This avoids running stty at every
external command by accidentally exporting it. Also note that
STTY should not be used for window size specifications; these
will not be local to the command.
If the parameter is set and empty, all of the above applies ex-
cept that stty is not run. This can be useful as a way to freeze
the tty around a single command, blocking its changes to tty set-
tings, similar to the ttyctl builtin.
TERM <S>
The type of terminal in use. This is used when looking up term-
cap sequences. An assignment to TERM causes zsh to re-initialize
the terminal, even if the value does not change (e.g.,
`TERM=$TERM'). It is necessary to make such an assignment upon
any change to the terminal definition database or terminal type
in order for the new settings to take effect.
TERMINFO <S>
A reference to your terminfo database, used by the `terminfo' li-
brary when the system has it; see terminfo(5). If set, this
causes the shell to reinitialise the terminal, making the
workaround `TERM=$TERM' unnecessary.
TERMINFO_DIRS <S>
A colon-seprarated list of terminfo databases, used by the `ter-
minfo' library when the system has it; see terminfo(5). This
variable is only used by certain terminal libraries, in particu-
lar ncurses; see terminfo(5) to check support on your system. If
set, this causes the shell to reinitialise the terminal, making
the workaround `TERM=$TERM' unnecessary. Note that unlike other
colon-separated arrays this is not tied to a zsh array.
TIMEFMT
The format of process time reports with the time keyword. The
default is `%J %U user %S system %P cpu %*E total'. Recognizes
the following escape sequences, although not all may be available
on all systems, and some that are available may not be useful:
%% A `%'.
%U CPU seconds spent in user mode.
%S CPU seconds spent in kernel mode.
%E Elapsed time in seconds.
%P The CPU percentage, computed as 100*(%U+%S)/%E.
%W Number of times the process was swapped.
%X The average amount in (shared) text space used in kilo-
bytes.
%D The average amount in (unshared) data/stack space used in
kilobytes.
%K The total space used (%X+%D) in kilobytes.
%M The maximum memory the process had in use at any time in
kilobytes.
%F The number of major page faults (page needed to be brought
from disk).
%R The number of minor page faults.
%I The number of input operations.
%O The number of output operations.
%r The number of socket messages received.
%s The number of socket messages sent.
%k The number of signals received.
%w Number of voluntary context switches (waits).
%c Number of involuntary context switches.
%J The name of this job.
A star may be inserted between the percent sign and flags print-
ing time (e.g., `%*E'); this causes the time to be printed in
`hh:mm:ss.ttt' format (hours and minutes are only printed if they
are not zero). Alternatively, `m' or `u' may be used (e.g.,
`%mE') to produce time output in milliseconds or microseconds,
respectively.
TMOUT If this parameter is nonzero, the shell will receive an ALRM sig-
nal if a command is not entered within the specified number of
seconds after issuing a prompt. If there is a trap on SIGALRM, it
will be executed and a new alarm is scheduled using the value of
the TMOUT parameter after executing the trap. If no trap is set,
and the idle time of the terminal is not less than the value of
the TMOUT parameter, zsh terminates. Otherwise a new alarm is
scheduled to TMOUT seconds after the last keypress.
TMPPREFIX
A pathname prefix which the shell will use for all temporary
files. Note that this should include an initial part for the
file name as well as any directory names. The default is
`/tmp/zsh'.
TMPSUFFIX
A filename suffix which the shell will use for temporary files
created by process substitutions (e.g., `=(list)'). Note that
the value should include a leading dot `.' if intended to be in-
terpreted as a file extension. The default is not to append any
suffix, thus this parameter should be assigned only when needed
and then unset again.
WORDCHARS <S>
A list of non-alphanumeric characters considered part of a word
by the line editor.
ZBEEP If set, this gives a string of characters, which can use all the
same codes as the bindkey command as described in the zsh/zle
module entry in zshmodules(1), that will be output to the termi-
nal instead of beeping. This may have a visible instead of an
audible effect; for example, the string `\e[?5h\e[?5l' on a vt100
or xterm will have the effect of flashing reverse video on and
off (if you usually use reverse video, you should use the string
`\e[?5l\e[?5h' instead). This takes precedence over the NOBEEP
option.
ZDOTDIR
The directory to search for shell startup files (.zshrc, etc), if
not $HOME.
zle_bracketed_paste
Many terminal emulators have a feature that allows applications
to identify when text is pasted into the terminal rather than be-
ing typed normally. For ZLE, this means that special characters
such as tabs and newlines can be inserted instead of invoking ed-
itor commands. Furthermore, pasted text forms a single undo
event and if the region is active, pasted text will replace the
region.
This two-element array contains the terminal escape sequences for
enabling and disabling the feature. These escape sequences are
used to enable bracketed paste when ZLE is active and disable it
at other times. Unsetting the parameter has the effect of ensur-
ing that bracketed paste remains disabled.
zle_highlight
An array describing contexts in which ZLE should highlight the
input text. See Character Highlighting in zshzle(1).
ZLE_LINE_ABORTED
This parameter is set by the line editor when an error occurs.
It contains the line that was being edited at the point of the
error. `print -zr -- $ZLE_LINE_ABORTED' can be used to recover
the line. Only the most recent line of this kind is remembered.
ZLE_REMOVE_SUFFIX_CHARS
ZLE_SPACE_SUFFIX_CHARS
These parameters are used by the line editor. In certain circum-
stances suffixes (typically space or slash) added by the comple-
tion system will be removed automatically, either because the
next editing command was not an insertable character, or because
the character was marked as requiring the suffix to be removed.
These variables can contain the sets of characters that will
cause the suffix to be removed. If ZLE_REMOVE_SUFFIX_CHARS is
set, those characters will cause the suffix to be removed; if
ZLE_SPACE_SUFFIX_CHARS is set, those characters will cause the
suffix to be removed and replaced by a space.
If ZLE_REMOVE_SUFFIX_CHARS is not set, the default behaviour is
equivalent to:
ZLE_REMOVE_SUFFIX_CHARS=$' \t\n;&|'
If ZLE_REMOVE_SUFFIX_CHARS is set but is empty, no characters
have this behaviour. ZLE_SPACE_SUFFIX_CHARS takes precedence, so
that the following:
ZLE_SPACE_SUFFIX_CHARS=$'&|'
causes the characters `&' and `|' to remove the suffix but to re-
place it with a space.
To illustrate the difference, suppose that the option AUTO_RE-
MOVE_SLASH is in effect and the directory DIR has just been com-
pleted, with an appended /, following which the user types `&'.
The default result is `DIR&'. With ZLE_REMOVE_SUFFIX_CHARS set
but without including `&' the result is `DIR/&'. With
ZLE_SPACE_SUFFIX_CHARS set to include `&' the result is `DIR &'.
Note that certain completions may provide their own suffix re-
moval or replacement behaviour which overrides the values de-
scribed here. See the completion system documentation in zsh-
compsys(1).
ZLE_RPROMPT_INDENT <S>
If set, used to give the indentation between the right hand side
of the right prompt in the line editor as given by RPS1 or
RPROMPT and the right hand side of the screen. If not set, the
value 1 is used.
Typically this will be used to set the value to 0 so that the
prompt appears flush with the right hand side of the screen.
This is not the default as many terminals do not handle this cor-
rectly, in particular when the prompt appears at the extreme bot-
tom right of the screen. Recent virtual terminals are more
likely to handle this case correctly. Some experimentation is
necessary.
zsh 5.9 May 14, 2022 ZSHPARAM(1)
Generated by dwww version 1.16 on Tue Dec 16 04:12:33 CET 2025.