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SIGPROCMASK(2) | System Calls Manual | SIGPROCMASK(2) |
NAME¶
sigprocmask
—
manipulate current signal mask
LIBRARY¶
Standard C Library (libc, -lc)SYNOPSIS¶
#include
<signal.h>
int
sigprocmask
(int
how, const sigset_t * restrict set,
sigset_t * restrict oset);
DESCRIPTION¶
Thesigprocmask
() system call examines and/or
changes the current signal mask (those signals that are blocked from
delivery). Signals are blocked if they are members of the current signal mask
set.
If set is not null, the action of
sigprocmask
() depends on the value of the
how argument. The signal mask is changed as a
function of the specified set and the current
mask. The function is specified by how using
one of the following values from
<signal.h>
:
SIG_BLOCK
- The new mask is the union of the current mask and the specified set.
SIG_UNBLOCK
- The new mask is the intersection of the current mask and the complement of the specified set.
SIG_SETMASK
- The current mask is replaced by the specified set.
SIGKILL
or
SIGSTOP
to be blocked.
In threaded applications, pthread_sigmask(3) must
be used instead of sigprocmask
().
RETURN VALUES¶
Thesigprocmask
() function returns the
value 0 if successful; otherwise the value -1 is returned and
the global variable errno is set to indicate
the error.
ERRORS¶
Thesigprocmask
() system call will fail and
the signal mask will be unchanged if one of the following occurs:
- [
EINVAL
] - The how argument has a value other than those listed here.
SEE ALSO¶
kill(2), sigaction(2), sigpending(2), sigsuspend(2), fpsetmask(3), pthread_sigmask(3), sigsetops(3)STANDARDS¶
Thesigprocmask
() system call is expected to
conform to IEEE Std 1003.1-1990
(“POSIX.1”).May 7, 2010 | Debian |