SIGPENDING
Section: Linux Programmer's Manual (2)
Updated: 2017-09-15
Index
Return to Main Contents
NAME
sigpending, rt_sigpending - examine pending signals
SYNOPSIS
#include <signal.h>
int sigpending(sigset_t *set);
Feature Test Macro Requirements for glibc (see
feature_test_macros(7)):
sigpending():
_POSIX_C_SOURCE
DESCRIPTION
sigpending()
returns the set of signals that are pending for delivery to the calling
thread (i.e., the signals which have been raised while blocked).
The mask of pending signals is returned in
set.
RETURN VALUE
sigpending()
returns 0 on success and -1 on error.
In the event of an error,
errno
is set to indicate the cause.
ERRORS
- EFAULT
-
set
points to memory which is not a valid part of the process address space.
CONFORMING TO
POSIX.1-2001, POSIX.1-2008.
NOTES
See
sigsetops(3)
for details on manipulating signal sets.
If a signal is both blocked and has a disposition of "ignored", it is
not
added to the mask of pending signals when generated.
The set of signals that is pending for a thread
is the union of the set of signals that is pending for that thread
and the set of signals that is pending for the process as a whole; see
signal(7).
A child created via
fork(2)
initially has an empty pending signal set;
the pending signal set is preserved across an
execve(2).
C library/kernel differences
The original Linux system call was named
sigpending().
However, with the addition of real-time signals in Linux 2.2,
the fixed-size, 32-bit
sigset_t
argument supported by that system call was no longer fit for purpose.
Consequently, a new system call,
rt_sigpending(),
was added to support an enlarged
sigset_t
type.
The new system call takes a second argument,
size_t sigsetsize,
which specifies the size in bytes of the signal set in
set.
The glibc
sigpending()
wrapper function hides these details from us, transparently calling
rt_sigpending()
when the kernel provides it.
BUGS
In versions of glibc up to and including 2.2.1,
there is a bug in the wrapper function for
sigpending()
which means that information about pending real-time signals
is not correctly returned.
SEE ALSO
kill(2),
sigaction(2),
signal(2),
sigprocmask(2),
sigsuspend(2),
sigsetops(3),
signal(7)
COLOPHON
This page is part of release 4.13 of the Linux
man-pages
project.
A description of the project,
information about reporting bugs,
and the latest version of this page,
can be found at
https://www.kernel.org/doc/man-pages/.
Index
- NAME
-
- SYNOPSIS
-
- DESCRIPTION
-
- RETURN VALUE
-
- ERRORS
-
- CONFORMING TO
-
- NOTES
-
- C library/kernel differences
-
- BUGS
-
- SEE ALSO
-
- COLOPHON
-
|
|
- Running on 
-
:
: 