sigprocmask — examine and change blocked signals
#include <signal.h>
int
sigprocmask( |
int | how, |
| const sigset_t * | set, | |
| sigset_t * | oldset); |
sigprocmask() is used to
change the signal mask, the set of currently blocked signals.
The behavior of the call is dependent on the value of
how, as follows.
SIG_BLOCKThe set of blocked signals is the union of the
current set and the set argument.
SIG_UNBLOCKThe signals in set are removed from the
current set of blocked signals. It is legal to attempt
to unblock a signal which is not blocked.
SIG_SETMASKThe set of blocked signals is set to the argument
set.
If oldset is
non-null, the previous value of the signal mask is stored in
oldset.
If set is NULL,
then the signal mask is unchanged (i.e., how is ignored), but the
current value of the signal mask is nevertheless returned in
oldset (it is not
NULL).
The use of sigprocmask() is
unspecified in a multithreaded process; see pthread_sigmask(3).
It is not possible to block SIGKILL or SIGSTOP. Attempts to do so are silently
ignored.
If SIGBUS, SIGFPE, SIGILL, or SIGSEGV are generated while they are
blocked, the result is undefined, unless the signal was
generated by the kill(2), sigqueue(2), or raise(3).
See sigsetops(3) for details on manipulating signal sets.
kill(2), pause(2), sigaction(2), signal(2), sigpending(2), sigqueue(2), sigsuspend(2), pthread_sigmask(3), sigsetops(3), signal(7)
This page is part of release 2.79 of the Linux man-pages project. A
description of the project, and information about reporting
bugs, can be found at
http://www.kernel.org/doc/man-pages/.
|
Copyright (c) 2005 Michael Kerrisk based on earlier work by faithcs.unc.edu and Mike Battersby <mibdeakin.edu.au> Permission is granted to make and distribute verbatim copies of this manual provided the copyright notice and this permission notice are preserved on all copies. Permission is granted to copy and distribute modified versions of this manual under the conditions for verbatim copying, provided that the entire resulting derived work is distributed under the terms of a permission notice identical to this one. Since the Linux kernel and libraries are constantly changing, this manual page may be incorrect or out-of-date. The author(s) assume no responsibility for errors or omissions, or for damages resulting from the use of the information contained herein. The author(s) may not have taken the same level of care in the production of this manual, which is licensed free of charge, as they might when working professionally. Formatted or processed versions of this manual, if unaccompanied by the source, must acknowledge the copyright and authors of this work. 2005-09-15, mtk, Created new page by splitting off from sigaction.2 |