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PTHREAD_SIGMASK(2)          BSD System Calls Manual         PTHREAD_SIGMASK(2)

NAME
     pthread_sigmask -- examine and/or change a thread's signal mask

SYNOPSIS
     #include <signal.h>

     int
     pthread_sigmask(int how, const sigset_t *restrict set, sigset_t *restrict oset);

DESCRIPTION
     The pthread_sigmask() function examines and/or changes the calling thread's signal mask.

     If set is not NULL, it specifies a set of signals to be modified, and how specifies what to set the
     signal mask to:

     SIG_BLOCK    Union of the current mask and set.

     SIG_UNBLOCK  Intersection of the current mask and the complement of set.

     SIG_SETMASK  set.

     If oset is not NULL, the previous signal mask is stored in the location pointed to by oset.

     SIGKILL and SIGSTOP cannot be blocked, and will be silently ignored if included in the signal mask.

RETURN VALUES
     If successful, pthread_sigmask() returns 0.  Otherwise, an error is returned.

ERRORS
     pthread_sigmask() will fail if:

     [EINVAL]           how is not one of the defined values.

LEGACY SYNOPSIS
     #include <pthread.h>
     #include <signal.h>

     The include file <pthread.h> is necessary.

SEE ALSO
     sigaction(2), sigpending(2), sigprocmask(2), sigsuspend(2), sigsetops(3), compat(5)

STANDARDS
     pthread_sigmask() conforms to ISO/IEC 9945-1:1996 (``POSIX.1'')

BSD                             April 27, 2000                             BSD