sigpause — atomically release blocked signals and wait for interrupt
#include <signal.h>
int sigpause( |
int sigmask) ; |
/* BSD */
int sigpause( |
int sig) ; |
/* System V / Unix95 */
Don't use this function. Use sigsuspend(2) instead.
The function sigpause
() is
designed to wait for some signal. It changes the process's
signal mask (set of blocked signals), and then waits for a
signal to arrive. Upon arrival of a signal, the original
signal mask is restored.
If sigpause
() returns, it
was interrupted by a signal and the return value is −1
with errno
set to EINTR.
The classical BSD version of this function appeared in
4.2BSD. It sets the process's signal mask to sigmask
. Unix95 standardized
the incompatible System V version of this function, which
removes only the specified signal sig
from the process's signal
mask. The unfortunate situation with two incompatible
functions with the same name was solved by the sigsuspend(2) function,
that takes a sigset_t
* argument (instead of an int).
On Linux, this routine is a system call only on the Sparc (sparc64) architecture.
Libc4 and libc5 only know about the BSD version.
Glibc uses the BSD version if the _BSD_SOURCE
feature test macro is defined
and none of _POSIX_SOURCE
,
_POSIX_C_SOURCE
, _XOPEN_SOURCE
, _GNU_SOURCE
, or _SVID_SOURCE
is defined. The System V
version is used if _XOPEN_SOURCE
is defined.
kill(2), sigaction(2), sigprocmask(2), sigsuspend(2), sigblock(3), sigvec(3), feature_test_macros(7)