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.