KILL(2-SVR3)        RISC/os Reference Manual         KILL(2-SVR3)



NAME
     kill - send a signal to a process or a group of processes

SYNOPSIS
     #include <bsd/sys/types.h>
     int kill (pid, sig)
     int pid, sig;

DESCRIPTION
     kill sends a signal to a process or a group of processes.
     The process or group of processes to which the signal is to
     be sent is specified by pid.  The signal that is to be sent
     is specified by sig and is either one from the list given in
     signal(2), or 0.  If sig is 0 (the null signal), error
     checking is performed but no signal is actually sent.  This
     can be used to check the validity of pid.

     The real or effective user ID of the sending process must
     match the real or effective user ID of the receiving pro-
     cess, unless the effective user ID of the sending process is
     super-user.

     The processes with a process ID of 0 and a process ID of 1
     are special processes [see intro(2)] and will be referred to
     below as proc0 and proc1, respectively.

     If pid is greater than zero, sig will be sent to the process
     whose process ID is equal to pid.  Pid may equal 1.

     If pid is 0, sig will be sent to all processes excluding
     proc0 and proc1 whose process group ID is equal to the pro-
     cess group ID of the sender.

     If pid is -1 and the effective user ID of the sender is not
     super-user, sig will be sent to all processes excluding
     proc0 and proc1 whose real user ID is equal to the effective
     user ID of the sender.

     If pid is -1 and the effective user ID of the sender is
     super-user, sig will be sent to all processes excluding
     proc0 and proc1.

     If pid is negative but not -1, sig will be sent to all
     processes whose process group ID is equal to the absolute
     value of pid.

ERRORS
     kill will fail and no signal will be sent if one or more of
     the following are true:

     [EINVAL]
             sig is not a valid signal number.



                        Printed 11/19/92                   Page 1

KILL(2-SVR3)        RISC/os Reference Manual         KILL(2-SVR3)



     [EINVAL]
             sig is SIGKILL and pid is 1 (proc1).

     [ESRCH] No process can be found corresponding to that speci-
             fied by pid.

     [EPERM] The user ID of the sending process is not super-
             user, and its real or effective user ID does not
             match the real or effective user ID of the receiving
             process.

SEE ALSO
     getpid(2), setpgrp(2), signal(2), sigset(2).
     kill(1) in the User's Reference Manual.

DIAGNOSTICS
     Upon successful completion, a value of 0 is returned.  Oth-
     erwise, a value of -1 is returned and errno is set to indi-
     cate the error.




































 Page 2                 Printed 11/19/92