SIGPROCMASK(2)

NAME
sigprocmask - manipulate the signal mask

SYNOPSIS
#include <signal.h> int sigprocmask(int how, const sigset_t *set, sigset_t *oset)

DESCRIPTION
Sigprocmask() examines or manipulates the signal mask. This mask is the set of signals that are currently blocked. The how argument determines the action that must be performed. In all cases the signal set referenced by oset, if not NULL, will be used to receive the old signal mask. The set argument, if not NULL, will be used to set or modify the current signal mask.

How can be one of:

SIG_BLOCK
    Add the signals referenced by set to the mask.

SIG_UNBLOCK
    Remove the signals referenced by set from the mask.

SIG_SETMASK
    Set the signal mask to the set referenced by set.

The value of how is ignored if set is NULL.

SEE ALSO
sigaction(2), sigpending(2), sigsuspend(2), sigset(3).

DIAGNOSTICS
Returns 0 on success and -1 on error. The error code is EFAULT for a bad set or oset address, or EINVAL for a bad how argument.

AUTHOR
Kees J. Bot (kjb@cs.vu.nl)