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# pgrep - Unix, Linux Command

# NAME

pgrep, pkill - look up or signal processes based on name and other attributes

# SYNOPSIS

pgrep [-flvx] [-d delimiter] [-n|-o] [-P ppid,...] [-g pgrp,...]
[-s sid,...] [-u euid,...] [-U uid,...] [-G gid,...]
[-t term,...] [pattern]

pkill [-signal] [-fvx] [-n|-o] [-P ppid,...] [-g pgrp,...]
[-s sid,...] [-u euid,...] [-U uid,...] [-G gid,...]
[-t term,...] [pattern]

# DESCRIPTION

pgrep looks through the currently running processes and lists the process IDs which matches 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 other hand,

pgrep -u root,daemon

will list the processes owned by root OR daemon.

pkill will send the specified signal (by default SIGTERM) to each process instead of listing them on stdout.

# OPTIONS

Tag | Description
--- | ---
-d delimiter
| Sets the string used to delimit each process ID in the output (by default a newline). (pgrep only.)
-f | The pattern is normally only matched against the process name. When -f is set, the full command line is used.
-g 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 gid,... | Only match processes whose real group ID is listed. Either the numerical or symbolical value may be used.
-l | List the process name as well as the process ID. (pgrep only.)
-n | Select only the newest (most recently started) of the matching processes.
-o | Select only the oldest (least recently started) of the matching processes.
-P ppid,...
| Only match processes whose parent process ID is listed.
-s 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 term,...
| Only match processes whose controlling terminal is listed. The terminal name should be specified without the "/dev/" prefix.
-u euid,...
| Only match processes whose effective user ID is listed. Either the numerical or symbolical value may be used.
-U uid,... | Only match processes whose real user ID is listed. Either the numerical or symbolical value may be used.
-v | Negates the matching.
-x | Only match processes whose name (or command line if -f is specified) exactly match the pattern.
-signal
| Defines the signal to send to each matched process. Either the numeric or the symbolic signal name can be used. (pkill only.)

# OPERANDS

Tag | Description
--- | ---
pattern
| Specifies an Extended Regular Expression for matching against the process names or command lines.

# EXAMPLES

Example 1: Find the process ID of the named daemon:

unix$ pgrep -u root named

Example 2: Make syslog reread its configuration file:

unix$ pkill -HUP syslogd

Example 3: Give detailed information on all xterm processes:

unix$ ps -fp $(pgrep -d, -x xterm)

Example 4: Make all netscape processes run nicer:

unix$ renice +4 ‘pgrep netscape‘

# EXIT STATUS

Tag | Description
--- | ---
0 | One or more processes matched the criteria.
1 | No processes matched.
2 | Syntax error in the command line.
3 | Fatal error: out of memory etc.

# NOTES

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/cmdline.

The running pgrep or pkill process will never report itself as a match.

# BUGS

The options -n and -o and -v can not be combined. Let me know if you need to do this.

Defunct processes are reported.

# SEE ALSO

# STANDARDS

pkill and pgrep were introduced in Sun’s Solaris 7. This implementation is fully compatible.

# AUTHOR

Kjetil Torgrim Homme <kjetilho@ifi.uio.no>

Albert Cahalan <albert@users.sf.net> is the current maintainer of the procps package.

Please send bug reports to <procps-feedback@lists.sf.net>

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