kill - terminate or signal processes
/usr/bin/kill -s signal_name pid...
/usr/bin/kill -l [exit_status]
/usr/bin/kill [-signal_name] pid...
/usr/bin/kill [-signal_number] pid...
The kill utility sends a signal to the process or processes
specified by each pid operand.
For each pid operand, the kill utility will perform actions
equivalent to the kill(2) function called with the following
1. The value of the pid operand will be used as the pid
2. The sig argument is the value specified by the -s option,
the -signal_name option, or the -signal_number option,
or, if none of these options is specified, by SIGTERM.
The signaled process must belong to the current user unless
the user is the super-user.
See NOTES for descriptions of the shell built-in versions of
The following options are supported:
-l (The letter ell.) Writes all values of signal_name
supported by the implementation, if no operand is
given. If an exit_status operand is given and it is a
value of the ? shell special parameter and wait
corresponding to a process that was terminated by a
signal, the signal_name corresponding to the signal
that terminated the process will be written. If an
exit_status operand is given and it is the unsigned
decimal integer value of a signal number, the
signal_name corresponding to that signal will be writ-
ten. Otherwise, the results are unspecified.
Specifies the signal to send, using one of the sym-
bolic names defined in the <signal.h> description.
Values of signal_name will be recognized in a case-
independent fashion, without the SIG prefix. In addi-
tion, the symbolic name 0 will be recognized,
representing the signal value zero. The corresponding
signal will be sent instead of SIGTERM.
Equivalent to -s signal_name.
Specifies a non-negative decimal integer,
signal_number, representing the signal to be used
instead of SIGTERM, as the sig argument in the effec-
tive call to kill(2).
The following operands are supported:
pid One of the following:
1. A decimal integer specifying a process or process
group to be signaled. The process or processes
selected by positive, negative and zero values of
the pid operand will be as described for the kill
function. If process number 0 is specified, all
processes in the process group are signaled. If the
first pid operand is negative, it should be pre-
ceded by -- to keep it from being interpreted as an
2. A job control job ID that identifies a background
process group to be signaled. The job control job
ID notation is applicable only for invocations of
kill in the current shell execution environment.
Note: The job control job ID type of pid is available
only on systems supporting the job control option.
A decimal integer specifying a signal number or the
exit status of a process terminated by a signal.
Process numbers can be found by using ps(1).
The job control job ID notation is not required to work as
expected when kill is operating in its own utility execution
environment. In either of the following examples:
example% nohup kill %1 &
example% system( "kill %1");
kill operates in a different environment and will not share
the shell's understanding of job numbers.
When the -l option is not specified, the standard output
will not be used.
When the -l option is specified, the symbolic name of each
signal will be written in the following format:
"%s%c", <signal_name>, <separator>
where the <signal_name> is in upper-case, without the SIG
prefix, and the <separator> will be either a newline charac-
ter or a space character. For the last signal written,
<separator> will be a newline character.
When both the -l option and exit_status operand are speci-
fied, the symbolic name of the corresponding signal will be
written in the following format:
Example 1: Sending the kill signal
Any of the commands:
example% kill -9 100 -165
example% kill -s kill 100 -165
example% kill -s KILL 100 -165
sends the SIGKILL signal to the process whose process ID is
100 and to all processes whose process group ID is 165,
assuming the sending process has permission to send that
signal to the specified processes, and that they exist.
Example 2: Avoiding ambiguity with an initial negative
To avoid an ambiguity of an initial negative number argument
specifying either a signal number or a process group, the
former will always be the case. Therefore, to send the
default signal to a process group (for example, 123), an
application should use a command similar to one of the fol-
example% kill -TERM -123
example% kill -- -123
See environ(5) for descriptions of the following environment
variables that affect the execution of kill: LANG, LC_ALL,
LC_CTYPE, LC_MESSAGES, and NLSPATH.
The following exit values are returned:
0 At least one matching process was found for each pid
operand, and the specified signal was successfully
processed for at least one matching process.
>0 An error occurred.
See attributes(5) for descriptions of the following attri-
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
| Availability | SUNWcsu |
| CSI | enabled |
| Interface Stability | Standard |
csh(1), jobs(1), ksh(1), ps(1), sh(1), shell_builtins(1),
wait(1), kill(2), signal(3C), signal(3HEAD), attributes(5),
The Bourne shell, sh, has a built-in version of kill to pro-
vide the functionality of the kill command for processes
identified with a jobid. The sh syntax is:
kill [ -sig ] [ pid ] [ %job ]...
The C-shell, csh, also has a built-in kill command, whose
The csh kill built-in sends the TERM (terminate) signal, by
default, or the signal specified, to the specified process
ID, the job indicated, or the current job. Signals are
either given by number or by name. There is no default. Typ-
ing kill does not send a signal to the current job. If the
signal being sent is TERM (terminate) or HUP (hangup), then
the job or process is sent a CONT (continue) signal as well.
-l Lists the signal names that can be sent.
The syntax of the ksh kill is:
The ksh kill sends either the TERM (terminate) signal or the
specified signal to the specified jobs or processes. Signals
are either given by number or by names (as given in
signal(3HEAD) stripped of the SIG prefix). If the signal
being sent is TERM (terminate) or HUP (hangup), then the job
or process will be sent a CONT (continue) signal if it is
stopped. The argument job can be the process id of a process
that is not a member of one of the active jobs. In the
second form, kill -l, the signal numbers and names are
Man(1) output converted with