sigsetops(3P)                                       sigsetops(3P)



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

     SYNOPSIS
          #include <signal.h>

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

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

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

          int sigfillset(set)
          sigset_t *set;

          int sigemptyset(set)
          sigset_t *set;

     DESCRIPTION
          These routines manipulate sets of signals.  They operate on
          data objects addressable by the application, not on any set
          of signals known to the system. The signal set modified by
          these rountines may be used as a parameter to
          sigagction(3P), sigprocmask(3P), sigpending(3P), or
          sigsispend(3P).  sigaddset adds the signal specified by
          pointed to by set.

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

          POSIX defines the following signals:

            SIGABRT           SIGPIPE           SIGCLD

            SIGALRM           SIGQUIT           SIGCONT

            SIGFPE            SIGSEGV           SIGSTOP

            SIGHUP            SIGTERM           SIGTSTP

            SIGILL            SIGUSR1           SIGTTIN

            SIGINT            SIGUSR2           SIGTTOU

            SIGKILL


          sigfillset initializes the signal set pointed to by set so

          that all POSIX-defined signals are included.


          sigemptyset initializes the signal set pointed to by set so

          that all the POSIX-defined signals are excluded.  Applica-

          tions must call sigemptyset for each object of type sigset_t



     April, 1990                                                     1

     sigsetops(3P)                                       sigsetops(3P)



          before any other use of the object.

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

     RETURN VALUE
          On successful completion, sigismember returns 1 if the
          specified signal is a member of the specified set and re-
          turns 0 if it is not.  On successful completion, each of the
          other functions returns 0.  For all the functions listed, if
          an error is detected, sigaddset, sigdelset, and sigismember
          returns -1 and set errno to indicate the error.

     ERRORS
          If any of the following conditions occur, the function re-
          turns -1 and sets errno to the corresponding value:

          [EINVAL]      The value of signo is not a valid signal
                        number.

          [EFAULT]      set is an invalid address.

     SEE ALSO
          sigaction(3P), sigpending(3P), sigprocmask(2P),
          sigsuspend(3P).






























     2                                                     April, 1990