huschi.net

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

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
       A call to setjmp() shall save the calling environment in its env  argu-
       ment 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 state-
          ment
        * One operand of a relational or equality operator with the other  op-
          erand 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 unde-
       fined.
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
       IEEE Std 1003.1-2001, <setjmp.h>
COPYRIGHT
       Portions of this text are reprinted and reproduced in  electronic  form
       from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
       -- Portable Operating System Interface (POSIX),  The  Open  Group  Base
       Specifications  Issue  6,  Copyright  (C) 2001-2003 by the Institute of
       Electrical and Electronics Engineers, Inc and The Open  Group.  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.opengroup.org/unix/online.html .

IEEE/The Open Group                  2003                           SETJMP(3P)