April 28, 1995 KILL 1

### NAME

kill - terminate or signal a process

### SYNOPSIS

kill [-s signal_name] pid ... kill -l [exit_status] kill -signal_name pid ... kill -signal_number pid ...

### DESCRIPTION

The kill utility sends a signal to the process(es) specified by the pid operand(s).

Only the super-user may send signals to other users' processes.

The options are as follows:

-s signal_name
  A symbolic signal name specifying the signal to be sent instead of the default ```TERM`.

-l[ exit_status]
  Display the name of the signal corresponding to exit_status. exit_status may be the exit status of a command killed by a signal (see the special sh(1) parameter `?') or a signal number.

  If no operand is given, display the names of all the signals.

-signal_name
  A symbolic signal name specifying the signal to be sent instead of the default ```TERM`.

-signal_number
  A non-negative decimal integer, specifying the signal to be sent instead of the default ```TERM`.

The following pids have special meanings:

-1
  If superuser, broadcast the signal to all processes; otherwise broadcast to all processes belonging to the user.
0
  Broadcast the signal to all processes in the current process group belonging to the user.

Some of the more commonly used signals:

1
  HUP (hang up)
2
  INT (interrupt)
3
  QUIT (quit)
6
  ABRT (abort)
9
  KILL (non-catchable, non-ignorable kill)
14
  ALRM (alarm clock)
15
  TERM (software termination signal)

kill is a built-in to csh(1); it allows job specifiers of the form ``%...'' as arguments so process id's are not as often used as kill arguments. See csh(1) for details.

### SEE ALSO

csh(1), pgrep(1), pkill(1), ps(1), kill(2), sigaction(2), signal(7)

### STANDARDS

The kill function is expected to be IEEE Std 1003.2 (``POSIX.2'') compatible.

### HISTORY

A kill command appeared in Version 6 `AT&T UNIX`.