Man page of kill
Section: User Commands (1)
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kill - Sends a signal to a running process
kill -l [exit_status]
kill [-signal_name|signal_number] process_ID...
kill -s signal_name process_ID...
The C shell has a built-in version of the
command. If you are using the C shell, and want to guarantee that you
are using the command described here, you must specify the full path
/usr/bin/kill. See the
page for a description of the built-in command.
Interfaces documented on this reference page conform to industry standards
kill: XPG4, XPG4-UNIX
Refer to the
reference page for more information
about industry standards and associated tags.
command supports the following options:
Lists signal names.
If you specify an exit status (a numeric value) or the shell special
$?, which expands to the exit status of the most
prints the name of the terminating
Specifies the signal to send, using one of the symbolic names
defined for required signals or job control signals. Values of
are recognized in both uppercase or lowercase letters,
and without the
prefix. The symbolic name
(zero), which represents the value 0 (zero), is also recognized.
The corresponding signal is sent instead of
Specifies the signal to send to the process. You can specify
either a name, stripped of the
prefix (such as
KILL), or a number (such as
9). For information
about signal names and numbers, see the
A process identification number
[Compaq] There are several special process identification numbers (PIDs)
that you can specify to cause the following special actions:
The signal is sent to all processes having a process group
ID equal to the process group ID of the sender, except those with PIDs 0 and
If the effective user ID of the sender is not 0 (root), the
signal is sent to all processes with a process group ID equal to the effective
user ID of the sender, except those with PIDs 0 and 1.
If the effective user ID of the sender is 0 (root), the signal is sent
to all processes, excluding numbers 0 and 1.
The signal is sent to all processes whose process group number
is equal to the absolute value of
PID. Note that
when you specify any negative PID, you must also specify the signal to be
sent, even the default signal
A decimal integer specifying a signal number or the exit status
of a process terminated by a signal.
command sends a signal to one or more running processes. The
default is the
signal (signal number
15), which usually terminates processes that do not ignore or catch
You identify the process to be signaled by specifying its process identification
number (also known as the process ID or PID). The shell displays the PID of
each process that is running in the background or, if you start more than
one process in a pipeline, the shell displays the number of the last process.
You can also use the
command to display PIDs.
[Compaq] The name of the
command is misleading
because many signals, including
SIGUSR1, do not terminate
you are operating with superuser authority, the process you wish to signal
must belong to you. When operating with superuser authority, you can signal
[Compaq] See the
system call for a complete
kill. Note that the
command contains a built-in subcommand named
the command and subcommand do not necessarily work in the same way. For information
on the subcommand, see
The following exit values are returned:
At least one matching process was found, and the specified
signal was successfully processed for at least one matching process.
An error occurred.
The following command terminates the process with the specified
This command terminates process
by sending it
signal. Note that process
might not actually terminate if it has made special arrangements
to ignore or catch the
The following command terminates several processes that ignore
the default signal:
kill -KILL 17285 15692
This command sends
signal usually cannot be ignored or caught.
The following command terminates all of your background processes:
This command sends the
signal to all members
of the shell process group. This includes all background processes started
&. Although the signal is sent to the shell, it
has no effect because the shell ignores the default signal
The following command terminates all of your processes and
logs you out:
kill -KILL 0
This command sends
to all members of the
shell process group. Because the shell cannot ignore
this also terminates the login shell and logs you out. If you are using multiple
windows, this closes the active window.
The following command terminate all the processes that you
kill -KILL -1
This command sends
to all the processes that
you own, even those that belong to other process groups. If you are using
multiple windows, this command closes all the windows.
The following command sends a specific signal to a specific
kill -USR1 1103
This command sends the
signal to process
1103. The action taken on the
is defined by the particular application you are running.
The following command lists the signal names in numerical
order, stripped of the
1) HUP 13) PIPE 25) XFSZ 37) RTMIN+4
2) INT 14) ALRM 26) VTALRM 38) RTMIN+5
3) QUIT 15) TERM 27) PROF 39) RTMIN+6
4) ILL 16) URG 28) WINCH 40) RTMIN+7
5) TRAP 17) STOP 29) PWR 41) RTMAX-7
6) LOST 18) TSTP 30) USR1 42) RTMAX-6
7) EMT 19) CONT 31) USR2 43) RTMAX-5
8) FPE 20) CHLD 32) RESV 44) RTMAX-4
9) KILL 21) TTIN 33) RTMIN 45) RTMAX-3
10) BUS 22) TTOU 34) RTMIN+1 46) RTMAX-2
11) SEGV 23) POLL 35) RTMIN+2 47) RTMAX-1
12) SYS 24) XCPU 36) RTMIN+3 48) RTMAX
The command output can vary from system to system.
The following environment variables affect the execution of
Provides a default value for the internationalization variables
that are unset or null. If
is unset or null, the corresponding value from the default locale is used.
If any of the internationalization variables contain an invalid setting, the
utility behaves as if none of the variables had been defined.
If set to a non-empty string value, overrides the values of
all the other internationalization variables.
Determines the locale for the interpretation of sequences
of bytes of text data as characters (for example, single-byte as opposed to
multibyte characters in arguments).
Determines the locale for the format and contents of diagnostic
messages written to standard error.
Determines the location of message catalogues for the processing
Specifies signal names.
sh(1b), POSIX shell
- EXIT STATUS
- ENVIRONMENT VARIABLES
- SEE ALSO
This document was created by
using the manual pages.
Time: 02:42:49 GMT, October 02, 2010