sigsetops(3C)                                                 sigsetops(3C)


   NAME
         sigemptyset, sigfillset, sigaddset, sigdelset, sigismember -
         manipulate sets of signals.

   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 sigset_t data types, representing the set
         of signals supported by the implementation.

         sigemptyset initializes the set pointed to by set to exclude all
         signals defined by the system.

         sigfillset initializes the set pointed to by set to include all
         signals defined by the system.

         sigaddset adds the individual signal specified by the value of signo
         to the set pointed to by set.

         sigdelset deletes the individual signal specified by the value of
         signo from the set pointed to by set.

         sigismember checks whether the signal specified by the value of signo
         is a member of the set pointed to by set.

         Any object of type sigset_t must be initialized by applying either
         sigemptyset or sigfillset before applying any other operation.

         sigaddset, sigdelset and sigismember will fail if the following is
         true:

         EINVAL         The value of the signo argument is not a valid signal
                        number.

         sigfillset will fail if the following is true:

         EFAULT         The set argument specifies an invalid address.





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   sigsetops(3C)                                                 sigsetops(3C)


   SEE ALSO
         sigaction(2), sigprocmask(2), sigpending(2), sigsuspend(2),
         signal(5).

   DIAGNOSTICS
         Upon successful completion, the sigismember function returns a value
         of one if the specified signal is a member of the specified set, or a
         value of zero if it is not. Upon successful completion, the other
         functions return a value of zero. Otherwise a value of -1 is returned
         and errno is set to indicate the error.











































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