PROLOG

       This  manual  page  is part of the POSIX Programmer's Manual.  The Linux implementation of
       this interface may differ (consult the corresponding Linux  manual  page  for  details  of
       Linux behavior), or the interface may not be implemented on Linux.

NAME

       sigaddset — add a signal to a signal set

SYNOPSIS

       #include <signal.h>

       int sigaddset(sigset_t *set, int signo);

DESCRIPTION

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

       Applications shall call either sigemptyset() or sigfillset() at least once for each object
       of  type  sigset_t  prior  to  any  other  use  of  that  object. If such an object is not
       initialized  in  this  way,  but  is  nonetheless  supplied  as  an  argument  to  any  of
       pthread_sigmask(),  sigaction(),  sigaddset(),  sigdelset(),  sigismember(), sigpending(),
       sigprocmask(), sigsuspend(), sigtimedwait(), sigwait(), or sigwaitinfo(), the results  are
       undefined.

RETURN VALUE

       Upon  successful completion, sigaddset() shall return 0; otherwise, it shall return −1 and
       set errno to indicate the error.

ERRORS

       The sigaddset() function may fail if:

       EINVAL The value of the signo argument is an invalid or unsupported signal number.

       The following sections are informative.

EXAMPLES

       None.

APPLICATION USAGE

       None.

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       Section 2.4, Signal Concepts, pthread_sigmask(), sigaction(), sigdelset(),  sigemptyset(),
       sigfillset(), sigismember(), sigpending(), sigsuspend()

       The Base Definitions volume of POSIX.1‐2008, <signal.h>

COPYRIGHT

       Portions  of  this  text  are  reprinted  and  reproduced in electronic form from IEEE Std
       1003.1, 2013 Edition, Standard for Information Technology  --  Portable  Operating  System
       Interface  (POSIX),  The Open Group Base Specifications Issue 7, Copyright (C) 2013 by the
       Institute of Electrical and Electronics Engineers, Inc  and  The  Open  Group.   (This  is
       POSIX.1-2008  with  the  2013  Technical  Corrigendum  1  applied.)  In  the  event of any
       discrepancy between this version and the original IEEE and The Open  Group  Standard,  the
       original  IEEE  and The Open Group Standard is the referee document. The original Standard
       can be obtained online at http://www.unix.org/online.html .

       Any typographical or formatting errors that appear in this page are most  likely  to  have
       been  introduced  during  the conversion of the source files to man page format. To report
       such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html .