SIGSETOPS(3)             BSD Library Functions Manual             SIGSETOPS(3)

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

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <signal.h>

     int
     sigaddset(sigset_t *set, int signo);

     int
     sigdelset(sigset_t *set, int signo);

     int
     sigemptyset(sigset_t *set);

     int
     sigfillset(sigset_t *set);

     int
     sigismember(const 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.

     These functions are provided as macros in the include file <signal.h>.
     Actual functions 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, 0 otherwise.  The other functions return 0.

ERRORS
     Currently, no errors are detected.

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

STANDARDS
     These functions are defined by IEEE Std 1003.1-1988 (``POSIX.1'').

BSD                              June 4, 1993                              BSD