killpg()

Send a signal to a process group

Synopsis:

#include <sys/types.h>
#include <signal.h>

int killpg( pid_t pgrp, 
            int sig );

Arguments:

pid: The ID of the process group that you want to send a signal to.
sig: Zero, or the signal that you want to send. For a complete list of signals, see “POSIX signals” in the documentation for SignalAction().

Library:

libc

Use the -l c option to qcc to link against this library. This library is usually included automatically.

Description:

The killpg() function sends the signal sig to the process group specified by pgrp. If sig is zero, no signal is sent, but pgrp is still checked for validity.

If pgrp is greater than 1, killpg (pgrp, sig) is equivalent to kill (−pgrp, sig).

Returns:

Zero, or -1 if an error occurs (errno is set).

Errors:

EAGAIN: Insufficient system resources are available to deliver the signal.
EINVAL: The signal sig is invalid or not supported.
EPERM: The process doesn't have permission to send this signal to any receiving process.
ESRCH: No process group can be found corresponding to the specified pgrp or pgrp is less than or equal to 1.

Examples:

See sigprocmask().

Classification:

POSIX 1003.1 XSI

Safety:
Cancellation point	No
Interrupt handler	No
Signal handler	Yes
Thread	Yes