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KILL(1) User Commands KILL(1)


kill - send a signal to a process


kill [options] <pid> [...]


The default signal for kill is TERM. Use -l or -L to list available signals. Particularly useful signals include HUP, INT, KILL, STOP, CONT, and 0. Alternate signals may be specified in three ways: -9, -SIGKILL or -KILL. Negative PID values may be used to choose whole process groups; see the PGID column in ps command output. A PID of -1 is special; it indicates all processes except the kill process itself and init.


<pid> [...]
Send signal to every <pid> listed.
Specify the signal to be sent. The signal can be specified by using name or number. The behavior of signals is explained in signal(7) manual page.
Use sigqueue(3) rather than kill(2) and the value argument is used to specify an integer to be sent with the signal. If the receiving process has installed a handler for this signal using the SA_SIGINFO flag to sigaction(2), then it can obtain this data via the si_value field of the siginfo_t structure.
List signal names. This option has optional argument, which will convert signal number to signal name, or other way round.
List signal names in a nice table.


Your shell (command line interpreter) may have a built-in kill command. You may need to run the command described here as /bin/kill to solve the conflict.


Kill all processes you can kill.
Translate number 11 into a signal name.
List the available signal choices in a nice table.
Send the default signal, SIGTERM, to all those processes.


kill(2), killall(1), nice(1), pkill(1), renice(1), signal(7), sigqueue(3), skill(1)


This command meets appropriate standards. The -L flag is Linux-specific.


Albert Cahalan wrote kill in 1999 to replace a bsdutils one that was not standards compliant. The util-linux one might also work correctly.


Please send bug reports to

2023-01-16 procps-ng