1. Technology
Linux / Unix Command: pgrep
Command Library

NAME

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

 

SYNOPSIS

pgrep [-flnvx] [-d delimiter] [-P ppid,...] [-g pgrp,...]
       [-s sid,...] [-u euid,...] [-U uid,...] [-G gid,...]

       [-t term,...] [pattern]

pkill [-signal] [-fnvx] [-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

-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.
-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

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

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.

 

SEE ALSO

ps(1) proc(5) regex(5)

 

STANDARDS

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

 


Important: Use the man command (% man) to see how a command is used on your particular computer.

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