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 processes 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]

If no operand is given, list the signal names; otherwise, write the signal name corresponding to exit_status.

-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.

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)

Some shells may provide a builtin kill command which is similar or identical to this utility. Consult the builtin(1) manual page.

See Also

builtin(1) , csh(1) , killall(1) , ps(1) , kill(2) , sigaction(2)

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.

Bugs

A replacement for the command ``kill 0'' for csh(1) users should be provided.

Table of Contents

• Name
• Synopsis
• Description
• See Also
• Standards
• History
• Bugs