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

       setjmp — set jump point for a non-local goto

SYNOPSIS

       #include <setjmp.h>

       int setjmp(jmp_buf env);

DESCRIPTION

       The  functionality  described  on  this  reference  page is aligned with the ISO C standard. Any conflict
       between the requirements described  here  and  the  ISO C  standard  is  unintentional.  This  volume  of
       POSIX.1‐2008 defers to the ISO C standard.

       A call to setjmp() shall save the calling environment in its env argument for later use by longjmp().

       It is unspecified whether setjmp() is a macro or a function. If a macro definition is suppressed in order
       to  access  an  actual  function,  or  a program defines an external identifier with the name setjmp, the
       behavior is undefined.

       An application shall ensure that an invocation of setjmp() appears in one of the following contexts only:

        *  The entire controlling expression of a selection or iteration statement

        *  One operand of a relational or  equality  operator  with  the  other  operand  an  integral  constant
           expression,  with  the resulting expression being the entire controlling expression of a selection or
           iteration statement

        *  The operand of a unary '!'  operator with the  resulting  expression  being  the  entire  controlling
           expression of a selection or iteration

        *  The entire expression of an expression statement (possibly cast to void)

       If the invocation appears in any other context, the behavior is undefined.

RETURN VALUE

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

ERRORS

       No errors are defined.

       The following sections are informative.

EXAMPLES

       None.

APPLICATION USAGE

       In general, sigsetjmp() is more useful in dealing with errors and interrupts encountered in  a  low-level
       subroutine of a program.

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       longjmp(), sigsetjmp()

       The Base Definitions volume of POSIX.1‐2008, <setjmp.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 .

IEEE/The Open Group                                   2013                                        SETJMP(3POSIX)