SYSTEMD-CAT(1) systemd-cat SYSTEMD-CAT(1)
NAME
systemd-cat - Connect a pipeline or program's output with the journal
SYNOPSIS
systemd-cat [OPTIONS...] [COMMAND] [ARGUMENTS...]
systemd-cat [OPTIONS...]
DESCRIPTION
systemd-cat may be used to connect the standard input and output of a
process to the journal, or as a filter tool in a shell pipeline to pass
the output the previous pipeline element generates to the journal.
If no parameter is passed, systemd-cat will write everything it reads
from standard input (stdin) to the journal.
If parameters are passed, they are executed as command line with
standard output (stdout) and standard error output (stderr) connected to
the journal, so that all it writes is stored in the journal.
OPTIONS
The following options are understood:
-h, --help
Print a short help text and exit.
--version
Print a short version string and exit.
-t, --identifier=
Specify a short string that is used to identify the logging tool. If
not specified, no identification string is set for the journal
entry, and the executable name (or "cat" if the input is read from a
pipe) will be used to describe the log source instead.
-p, --priority=
Specify the default priority level for the logged messages. Pass one
of "emerg", "alert", "crit", "err", "warning", "notice", "info",
"debug", or a value between 0 and 7 (corresponding to the same named
levels). These priority values are the same as defined by syslog(3).
Defaults to "info". Note that this simply controls the default,
individual lines may be logged with different levels if they are
prefixed accordingly. For details, see --level-prefix= below.
--stderr-priority=
Specifies the default priority level for messages from the process's
standard error output (stderr). Usage of this option is the same as
the --priority= option, above, and both can be used at once. When
both are used, --priority= will specify the default priority for
standard output (stdout).
If --stderr-priority= is not specified, messages from stderr will
still be logged, with the same default priority level as stdout.
Also, note that when stdout and stderr use the same default
priority, the messages will be strictly ordered, because one channel
is used for both. When the default priority differs, two channels
are used, and so stdout messages will not be strictly ordered with
respect to stderr messages - though they will tend to be
approximately ordered.
Added in version 241.
--level-prefix=
Controls whether lines read are parsed for syslog priority level
prefixes. If enabled (the default), a line prefixed with a priority
prefix such as "<5>" is logged at priority 5 ("notice"), and
similarly for the other priority levels. Takes a boolean argument.
--namespace=
Specifies the journal namespace to which the standard IO should be
connected. For details about journal namespaces, see systemd-
journald.service(8).
Added in version 256.
EXIT STATUS
On success, 0 is returned, a non-zero failure code otherwise.
EXAMPLES
Example 1. Invoke a program
This calls /bin/ls with standard output and error connected to the
journal:
# systemd-cat ls
Example 2. Usage in a shell pipeline
This builds a shell pipeline also invoking /bin/ls and writes the output
it generates to the journal:
# ls | systemd-cat
Even though the two examples have very similar effects, the first is
preferable, since only one process is running at a time and both stdout
and stderr are captured, while in the second example, only stdout is
captured.
SEE ALSO
systemd(1), systemctl(1), logger(1)
systemd 257.9 SYSTEMD-CAT(1)
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