ultrix man page for sigdelset

sigsetops(3)						     Library Functions Manual						      sigsetops(3)

Name
       sigemptyset, sigfillset, sigaddset, sigdelset, sigismember - manipulate signal sets (POSIX)

Syntax
       #include <signal.h>

       int sigemptyset(set)
       sigset_t *set;

       int sigfillset (set)
       sigset_t *set;

       int sigaddset(set,sig)
       sigset_t *set;
       int sig;

       int sigdelset(set,sig)
       sigset_t *set;
       int sig;

       int sigismember(set,sig)
       sigset_t *set;
       int sig;

Description
       The functions manipulate signal sets used by the other POSIX signal functions

       The function initializes the signal set pointed to by the argument set so that all signals are excluded.

       The function initializes the signal set pointed to by the argument set so that all signals are included.

       The  and functions respectively add and delete the individual signal specified by the value of the argument sig from the signal set pointed
       to by the argument set.

       The function tests whether the signal specified by the value of the argument sig is a member of the set pointed to by the argument set.

Return Values
       Upon successful completion, the function returns a value of 1 if the specified signal is a member of the set.  If it is not a member of the
       set, a value of 0 is returned.

       If the or functions fail a -1 value is returned and errno is set to indicate the reason.

Diagnostics
       The function will fail and the signal mask will remain unchanged if one of the following occur:

       [EINVAL]       The value of the sig argument is not a valid signal number

See Also
       sigprocmask(3), sigaction(3), sigsuspend(3), sigpending(2)

																      sigsetops(3)