NAME

sigsetmask - set current signal mask

LIBRARY

Standard C Library (libc, -lc)

SYNOPSIS



int sigsetmask(int mask) sigmask(signum)

DESCRIPTION

This interface is made obsolete by: sigprocmask(2).

sigsetmask() sets the current signal mask Signals are blocked from delivery if the corresponding bit in mask is a 1; the macro sigmask() is provided to construct the mask for a given signum.

The system quietly disallows SIGKILL or SIGSTOP to be blocked.

RETURN VALUES

The previous set of masked signals is returned.

EXAMPLES

The following example using sigsetmask():
int omask;
        

omask = sigblock(sigmask(SIGINT) | sigmask(SIGHUP));

...

sigsetmask(omask & ~(sigmask(SIGINT) | sigmask(SIGHUP)));

Could be converted literally to:

sigset_t set, oset;
        

sigemptyset(&set); sigaddset(&set, SIGINT); sigaddset(&set, SIGHUP); sigprocmask(SIG_BLOCK, &set, &oset);

...

sigdelset(&oset, SIGINT); sigdelset(&oset, SIGHUP); sigprocmask(SIG_SETMASK, &oset, NULL);

Another, clearer, alternative is:

sigset_t set;
        

sigemptyset(&set); sigaddset(&set, SIGINT); sigaddset(&set, SIGHUP); sigprocmask(SIG_BLOCK, &set, NULL);

...

sigprocmask(SIG_UNBLOCK, &set, NULL);

To completely clear the signal mask using sigsetmask() one can do:

(void) sigsetmask(0);

Which can be expressed via sigprocmask(2) as:

sigset_t eset;
        

sigemptyset(&eset); (void) sigprocmask(SIG_SETMASK, &eset, NULL);

SEE ALSO

kill(2), sigaction(2), sigprocmask(2), sigsuspend(2), sigblock(3), sigsetops(3), sigvec(3)

HISTORY

The sigsetmask() function call appeared in 4.2BSD and has been deprecated.