sigsetjmp(3p) — Linux manual page


SIGSETJMP(3P)             POSIX Programmer's Manual            SIGSETJMP(3P)

PROLOG         top

       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         top

       sigsetjmp — set jump point for a non-local goto

SYNOPSIS         top

       #include <setjmp.h>

       int sigsetjmp(sigjmp_buf env, int savemask);

DESCRIPTION         top

       The sigsetjmp() function shall be equivalent to the setjmp()
       function, except as follows:

        *  References to setjmp() are equivalent to sigsetjmp().

        *  References to longjmp() are equivalent to siglongjmp().

        *  If the value of the savemask argument is not 0, sigsetjmp() shall
           also save the current signal mask of the calling thread as part
           of the calling environment.

RETURN VALUE         top

       If the return is from a successful direct invocation, sigsetjmp()
       shall return 0. If the return is from a call to siglongjmp(),
       sigsetjmp() shall return a non-zero value.

ERRORS         top

       No errors are defined.

       The following sections are informative.

EXAMPLES         top



       The distinction between setjmp()/longjmp() and
       sigsetjmp()/siglongjmp() is only significant for programs which use
       sigaction(), sigprocmask(), or sigsuspend().

       Note that since this function is defined in terms of setjmp(), if
       savemask is zero, it is unspecified whether the signal mask is saved.

RATIONALE         top

       The ISO C standard specifies various restrictions on the usage of the
       setjmp() macro in order to permit implementors to recognize the name
       in the compiler and not implement an actual function. These same
       restrictions apply to the sigsetjmp() macro.

       There are processors that cannot easily support these calls, but this
       was not considered a sufficient reason to exclude them.

       4.2 BSD, 4.3 BSD, and XSI-conformant systems provide functions named
       _setjmp() and _longjmp() that, together with setjmp() and longjmp(),
       provide the same functionality as sigsetjmp() and siglongjmp().  On
       those systems, setjmp() and longjmp() save and restore signal masks,
       while _setjmp() and _longjmp() do not. On System V Release 3 and in
       corresponding issues of the SVID, setjmp() and longjmp() are
       explicitly defined not to save and restore signal masks. In order to
       permit existing practice in both cases, the relation of setjmp() and
       longjmp() to signal masks is not specified, and a new set of
       functions is defined instead.

       The longjmp() and siglongjmp() functions operate as in the previous
       issue provided the matching setjmp() or sigsetjmp() has been
       performed in the same thread. Non-local jumps into contexts saved by
       other threads would be at best a questionable practice and were not
       considered worthy of standardization.



SEE ALSO         top

       pthread_sigmask(3p), siglongjmp(3p), signal(3p), sigsuspend(3p)

       The Base Definitions volume of POSIX.1‐2008, setjmp.h(0p)

COPYRIGHT         top

       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 .

       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 .

IEEE/The Open Group                 2013                       SIGSETJMP(3P)

Pages that refer to this page: setjmp.h(0p)longjmp(3p)_longjmp(3p)setjmp(3p)_setjmp(3p)sigaltstack(3p)siglongjmp(3p)sleep(3p)