kill(2) — sys5



KILL(2)         DOMAIN/IX Reference Manual (SYS5)         KILL(2)



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

USAGE
     int kill (pid, sig)
     int pid, sig;

DESCRIPTION
     Kill sends a signal to a process or a group of processes,
     denoted by pid.  The signal is named by Sig names the signal
     that kill sends, and is either zero, or a number denoting
     one of the signals given in the list in signal(2).  If sig
     is zero (the null signal), kill performs error checking, but
     does not send a signal.  This can be used to check the vali-
     dity 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 process with a process ID of 1 is a special process, and
     is referred to below as proc1.

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

     If pid is 0, sig is sent to all processes, except proc1,
     whose process group ID is equal to the process group ID of
     the sender.

     If pid is -1 and the effective user ID of the sender is not
     super-user, sig is sent to all processes excluding 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 is sent to all processes excluding proc1.

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

RETURN VALUE
     Kill returns zero on successful execution.  Otherwise, it
     returns -1 and sets errno to indicate the error.

ERRORS
     Kill will fail without sending a signal, if one or more of
     the following is true:

     [EINVAL]       Sig is not a valid signal number.



Printed 5/10/85                                            KILL-1



KILL(2)         DOMAIN/IX Reference Manual (SYS5)         KILL(2)



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

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

     [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.

RELATED INFORMATION
     kill(1), getpid(2), setpgrp(2), signal(2)












































KILL-2                                            Printed 5/10/85

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