Unix/Linux Go Back    


OpenDarwin 7.2.1 - man page for kill (opendarwin section 2)

Linux & Unix Commands - Search Man Pages
Man Page or Keyword Search:   man
Select Man Page Set:       apropos Keyword Search (sections above)


KILL(2) 			     BSD System Calls Manual				  KILL(2)

NAME
     kill -- send signal to a process

SYNOPSIS
     #include <signal.h>

     int
     kill(pid_t pid, int sig);

DESCRIPTION
     The kill() function sends the signal given by sig to pid, a process or a group of processes.
     Sig may be one of the signals specified in sigaction(2) or it may be 0, in which case error
     checking is performed but no signal is actually sent.  This can be used to check the valid-
     ity of pid.

     For a process to have permission to send a signal to a process designated by pid, the real
     or effective user ID of the receiving process must match that of the sending process or the
     user must have appropriate privileges (such as given by a set-user-ID program or the user is
     the super-user).  A single exception is the signal SIGCONT, which may always be sent to any
     descendant of the current process.

     If pid is greater than zero:
	     Sig is sent to the process whose ID is equal to pid.

     If pid is zero:
	     Sig is sent to all processes whose group ID is equal to the process group ID of the
	     sender, and for which the process has permission; this is a variant of killpg(2).

     If pid is -1:
	     If the user has super-user privileges, the signal is sent to all processes excluding
	     system processes and the process sending the signal.  If the user is not the super
	     user, the signal is sent to all processes with the same uid as the user excluding
	     the process sending the signal.  No error is returned if any process could be sig-
	     naled.

     For compatibility with System V, if the process number is negative but not -1, the signal is
     sent to all processes whose process group ID is equal to the absolute value of the process
     number.  This is a variant of killpg(2).

RETURN VALUES
     Upon successful completion, a value of 0 is returned.  Otherwise, a value of -1 is returned
     and errno is set to indicate the error.

ERRORS
     Kill() will fail and no signal will be sent if:

     [EINVAL]		Sig is not a valid signal number.

     [ESRCH]		No process can be found corresponding to that specified by pid.

     [ESRCH]		The process id was given as 0 but the sending process does not have a
			process group.

     [EPERM]		The sending process is not the super-user and its effective user id does
			not match the effective user-id of the receiving process.  When signaling
			a process group, this error is returned if any members of the group could
			not be signaled.

SEE ALSO
     getpid(2), getpgrp(2), killpg(2), sigaction(2)

STANDARDS
     The kill() function is expected to conform to IEEE Std 1003.1-1988 (``POSIX.1'').

4th Berkeley Distribution		  April 19, 1994		4th Berkeley Distribution
Unix & Linux Commands & Man Pages : 2000 - 2018 Unix and Linux Forums


All times are GMT -4. The time now is 02:20 PM.