SIGSETOPS(3)            NetBSD Library Functions Manual           SIGSETOPS(3)

NAME
     sigemptyset, sigfillset, sigaddset, sigdelset, sigismember -- manipulate
     signal sets

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <signal.h>

     int
     sigemptyset(sigset_t *set);

     int
     sigfillset(sigset_t *set);

     int
     sigaddset(sigset_t *set, int signo);

     int
     sigdelset(sigset_t *set, int signo);

     int
     sigismember(sigset_t *set, int signo);

DESCRIPTION
     These functions manipulate signal sets stored in a sigset_t.  Either
     sigemptyset() or sigfillset() must be called for every object of type
     sigset_t before any other use of the object.

     The sigemptyset() function initializes a signal set to be empty.

     The sigfillset() function initializes a signal set to contain all sig-
     nals.

     The sigaddset() function adds the specified signal signo to the signal
     set.

     The sigdelset() function deletes the specified signal signo from the sig-
     nal set.

     The sigismember() function returns whether a specified signal signo is
     contained in the signal set.

     sigemptyset() and sigfillset() are provided as macros, but actual func-
     tions are available if their names are undefined (with #undef name).

RETURN VALUES
     The sigismember() function returns 1 if the signal is a member of the
     set, a 0 otherwise.  The other functions return 0 upon success.  A -1
     return value indicates an error occurred and the global variable errno is
     set to indicate the reason.

ERRORS
     These functions could fail if one of the following occurs:

     [EINVAL]           signo has an invalid value.

SEE ALSO
     kill(2), sigaction(2), sigsuspend(2), signal(7)

STANDARDS
     These functions conform to ISO/IEC 9945-1:1990 (``POSIX.1'').

NetBSD 8.1                       June 4, 1993                       NetBSD 8.1