pgrep, pkill - look up or signal processes based on name and other attributes
looks through the currently running processes and lists the process
IDs which match the selection criteria to stdout. All the criteria have to
match. For example,
- $ pgrep -u root sshd
will only list the processes called sshd
AND owned by root
. On the
- $ pgrep -u root,daemon
will list the processes owned by root
will send the specified signal (by default SIGTERM
) to each
process instead of listing them on stdout.
- --signal signal Defines the signal to send to each matched
process. Either the numeric or the symbolic signal name can be used.
- -c, --count
- Suppress normal output; instead print a count of matching processes. When
count does not match anything, e.g. returns zero, the command will return
- -d, --delimiter delimiter
- Sets the string used to delimit each process ID in the output (by default
a newline). (pgrep only.)
- -f, --full
- The pattern is normally only matched against the process name. When
-f is set, the full command line is used.
- -g, --pgroup pgrp,...
- Only match processes in the process group IDs listed. Process group 0 is
translated into pgrep's or pkill's own process group.
- -G, --group gid,...
- Only match processes whose real group ID is listed. Either the numerical
or symbolical value may be used.
- -i, --ignore-case
- Match processes case-insensitively.
- -l, --list-name
- List the process name as well as the process ID. (pgrep only.)
- -a, --list-full
- List the full command line as well as the process ID. (pgrep
- -n, --newest
- Select only the newest (most recently started) of the matching
- -o, --oldest
- Select only the oldest (least recently started) of the matching
- -P, --parent ppid,...
- Only match processes whose parent process ID is listed.
- -s, --session sid,...
- Only match processes whose process session ID is listed. Session ID 0 is
translated into pgrep's or pkill's own session ID.
- -t, --terminal term,...
- Only match processes whose controlling terminal is listed. The terminal
name should be specified without the "/dev/" prefix.
- -u, --euid euid,...
- Only match processes whose effective user ID is listed. Either the
numerical or symbolical value may be used.
- -U, --uid uid,...
- Only match processes whose real user ID is listed. Either the numerical or
symbolical value may be used.
- -v, --inverse
- Negates the matching. This option is usually used in pgrep's
context. In pkill's context the short option is disabled to avoid
accidental usage of the option.
- -w, --lightweight
- Shows all thread ids instead of pids in pgrep's context. In
pkill's context this option is disabled.
- -x, --exact
- Only match processes whose names (or command line if -f is specified)
exactly match the pattern.
- -F, --pidfile file
- Read PID's from file. This option is perhaps more useful for
pkill than pgrep.
- -L, --logpidfile
- Fail if pidfile (see -F) not locked.
- --ns pid
- Match processes that belong to the same namespaces. Required to run as
root to match processes from other users. See --nslist for how to limit
which namespaces to match.
- --nslist name,...
- Match only the provided namespaces. Available namespaces: ipc, mnt, net,
- -V, --version
- Display version information and exit.
- -h, --help
- Display help and exit.
- Specifies an Extended Regular Expression for matching against the process
names or command lines.
Example 1: Find the process ID of the named
- $ pgrep -u root named
Example 2: Make syslog
reread its configuration file:
- $ pkill -HUP syslogd
Example 3: Give detailed information on all xterm
- $ ps -fp $(pgrep -d, -x xterm)
Example 4: Make all netscape
processes run nicer:
- $ renice +4 $(pgrep netscape)
- One or more processes matched the criteria.
- No processes matched.
- Syntax error in the command line.
- Fatal error: out of memory etc.
The process name used for matching is limited to the 15 characters present in
the output of /proc/ pid
/stat. Use the -f option to match against the
complete command line, /proc/ pid
The running pgrep
process will never report itself as a
The options -n
can not be combined. Let me
know if you need to do this.
Defunct processes are reported.
Kjetil Torgrim Homme
Please send bug reports to