1SETJMP(3P)                 POSIX Programmer's Manual                SETJMP(3P)
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PROLOG

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

13       setjmp — set jump point for a non-local goto
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SYNOPSIS

16       #include <setjmp.h>
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18       int setjmp(jmp_buf env);
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DESCRIPTION

21       The functionality described on this reference page is aligned with  the
22       ISO C  standard.  Any  conflict between the requirements described here
23       and the ISO C standard is unintentional. This  volume  of  POSIX.1‐2008
24       defers to the ISO C standard.
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26       A  call to setjmp() shall save the calling environment in its env argu‐
27       ment for later use by longjmp().
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29       It is unspecified whether setjmp() is a macro or a function. If a macro
30       definition  is  suppressed  in order to access an actual function, or a
31       program defines an external identifier with the name setjmp, the behav‐
32       ior is undefined.
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34       An  application  shall ensure that an invocation of setjmp() appears in
35       one of the following contexts only:
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37        *  The entire controlling  expression  of  a  selection  or  iteration
38           statement
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40        *  One operand of a relational or equality operator with the other op‐
41           erand an integral constant expression, with the  resulting  expres‐
42           sion  being  the  entire  controlling  expression of a selection or
43           iteration statement
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45        *  The operand of a unary '!'  operator with the resulting  expression
46           being the entire controlling expression of a selection or iteration
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48        *  The  entire expression of an expression statement (possibly cast to
49           void)
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51       If the invocation appears in any other context, the behavior  is  unde‐
52       fined.
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RETURN VALUE

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

60       No errors are defined.
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62       The following sections are informative.
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EXAMPLES

65       None.
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APPLICATION USAGE

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

72       None.
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FUTURE DIRECTIONS

75       None.
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SEE ALSO

78       longjmp(), sigsetjmp()
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80       The Base Definitions volume of POSIX.1‐2008, <setjmp.h>
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83       Portions of this text are reprinted and reproduced in  electronic  form
84       from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology
85       -- Portable Operating System Interface (POSIX),  The  Open  Group  Base
86       Specifications Issue 7, Copyright (C) 2013 by the Institute of Electri‐
87       cal and Electronics Engineers,  Inc  and  The  Open  Group.   (This  is
88       POSIX.1-2008  with  the  2013  Technical Corrigendum 1 applied.) In the
89       event of any discrepancy between this version and the original IEEE and
90       The  Open Group Standard, the original IEEE and The Open Group Standard
91       is the referee document. The original Standard can be  obtained  online
92       at http://www.unix.org/online.html .
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94       Any  typographical  or  formatting  errors that appear in this page are
95       most likely to have been introduced during the conversion of the source
96       files  to  man page format. To report such errors, see https://www.ker‐
97       nel.org/doc/man-pages/reporting_bugs.html .
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101IEEE/The Open Group                  2013                           SETJMP(3P)
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