HP-UX Reference (11i v3 07/02) - 1 User Commands A-M (vol 1)
k
kill(1) kill(1)
15 SIGTERM Terminate Terminate; can be trapped
24 SIGSTOP Stop Pause the process; cannot be trapped
25 SIGTSTP Terminal stop Pause the process; can be trapped
26 SIGCONT Continue Run a stopped process
SIGNULL (0), the null signal, invokes error checking but no signal is actually sent. This can be used to
test the validity or existence of pid.
SIGTERM (15), the (default) terminate signal, can be trapped by the receiving process, allowing the
receiver to execute an orderly shutdown or to ignore the signal entirely. For orderly operations, this is the
preferred choice.
SIGKILL (9), the kill signal, forces a process to terminate immediately. Since
SIGKILL cannot be
trapped or ignored, it is useful for terminating a process that does not respond to
SIGTERM.
The receiving process must belong to the user of the sending process, unless the user has appropriate
privileges.
As a single special case, the continue signal
SIGCONT can be sent to any process that is a member of the
same session as the sending process.
RETURN VALUE
Upon completion,
kill returns with one of the following values:
0 At least one matching process was found for each pid operand, and the specified signal was suc-
cessfully processed for at least one matching process.
>0 An error occurred.
EXAMPLES
The command:
kill 6135
signals process number 6135 to terminate. This gives the process an opportunity to exit gracefully (remov-
ing temporary files, etc.).
The following equivalent commands:
kill -s SIGKILL 6135
kill -s KILL 6135
kill -s 9 6135
kill -SIGKILL 6135
kill -KILL 6135
kill -9 6135
terminate process number 6135 abruptly by sending a SIGKILL signal to the process. This tells the ker-
nel to remove the process immediately.
WARNINGS
If a process hangs during some operation (such as I/O) so that it is never scheduled, it cannot die until it is
allowed to run. Thus, such a process may never go away after the kill. Similarly, defunct processes (see
ps(1)) may have already finished executing, but remain on the system until their parent reaps them (see
wait(2)). Using kill to send signals to them has no effect.
Some non-HP-UX implementations provide kill only as a shell built-in command.
DEPENDENCIES
This manual entry describes the external command /usr/bin/kill and the built-in kill command of
the POSIX shell (see sh-posix(1)). Other shells, such as C and Korn (see csh(1) and ksh(1) respectively),
also provide kill as a built-in command. The syntax for and output from these built-ins may be different.
SEE ALSO
csh(1), ksh(1), ps(1), sh(1), sh-posix(1), kill(2), wait(2), signal(5).
STANDARDS CONFORMANCE
kill: SVID2, SVID3, XPG2, XPG3, XPG4, POSIX.2
HP-UX 11i Version 3: February 2007 − 2 − Hewlett-Packard Company 483