kill(2) kill(2)
NAME
kill -- (OBSOLETE, REMOVED) send signal to a process
SYNOPSIS
#include <sys/types.h>
#include <signal.h>
int kill pid_t pid, int sig);
DESCRIPTION
OBSOLETE and REMOVED. USE PTHREAD_KILL. The kill system can be used to
send any signal to any process group or process. In RTLinux there is a
single process and a single process group for each processor. The pro-
cess group and the process identifier for that processor is the cpu
number + 1 (so that we can handle the stupid 0 convention described
below).
If pid is positive, then signal sig is sent to pid.
If pid equals 0, then sig is sent to every process in the process group
of the current process. This is equivalent to sending the signal to the
current process in RTLinux.
If pid equals -1, then sig is sent to every process except for the
first one, from higher numbers in the process table to lower.
If pid is less than -1, then sig is sent to every process in the pro-
cess group -pid.
If sig is 0, then no signal is sent, but error checking is still per-
formed.
RETURN VALUE
On success, zero is returned. On error, -1 is returned, and errno is
set appropriately.
ERRORS
EINVAL An invalid signal was specified.
ESRCH The pid or process group does not exit. Note that an exist-
ing process might be a zombie -- a process which already com-
mitted termination, but has not yet been wait()ed for.
EPERM The process does not have permission to send the signal to
any of the receiving processes. For a process to have per-
mission to send a signal to process pid, it must either have
root privileges, or the real or effective user ID of the
sending process must equal the real or saved set-user-ID of
the receiving process.
BUGS
It is impossible to send a signal to task number one, the init process,
for which it has not installed a signal handler. This is done to
assure the system is not brought down accidentally.
NOTES
In RTLinux, process number one is not special--it is just the process
on processor 0. In a single processor system this is the only process
identifier.
CONFORMING TO
SVr4, SVID, POSIX.1, X/OPEN, BSD 4.3
SEE ALSO
UNIX spec exit(2) (link to URL ../susv2/xsh/exit.html) , UNIX spec
exit(3) (link to URL ../susv2/xsh/exit.html) , UNIX spec signal(2)
(link to URL ../susv2/xsh/signal.html) , UNIX spec signal(7) (link to
URL ../susv2/xsh/signal.html)
(C)2001 FSMLabs Inc.
All rights reserved.
kill(2)
