setjmp(3p) [posix man page]
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 correspond- ing 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 Technol- ogy -- 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 Stan- dard 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(3P)
Check Out this Related Man Page
_LONGJMP(3P) POSIX Programmer's Manual _LONGJMP(3P) PROLOG
This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the correspond- ing Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux. NAME
_longjmp, _setjmp -- non-local goto SYNOPSIS
#include <setjmp.h> void _longjmp(jmp_buf env, int val); int _setjmp(jmp_buf env); DESCRIPTION
The _longjmp() and _setjmp() functions shall be equivalent to longjmp() and setjmp(), respectively, with the additional restriction that _longjmp() and _setjmp() shall not manipulate the signal mask. If _longjmp() is called even though env was never initialized by a call to _setjmp(), or when the last such call was in a function that has since returned, the results are undefined. RETURN VALUE
Refer to longjmp() and setjmp(). ERRORS
No errors are defined. The following sections are informative. EXAMPLES
None. APPLICATION USAGE
If _longjmp() is executed and the environment in which _setjmp() was executed no longer exists, errors can occur. The conditions under which the environment of the _setjmp() no longer exists include exiting the function that contains the _setjmp() call, and exiting an inner block with temporary storage. This condition might not be detectable, in which case the _longjmp() occurs and, if the environment no longer exists, the contents of the temporary storage of an inner block are unpredictable. This condition might also cause unexpected process ter- mination. If the function has returned, the results are undefined. Passing longjmp() a pointer to a buffer not created by setjmp(), passing _longjmp() a pointer to a buffer not created by _setjmp(), passing siglongjmp() a pointer to a buffer not created by sigsetjmp(), or passing any of these three functions a buffer that has been modified by the user can cause all the problems listed above, and more. The _longjmp() and _setjmp() functions are included to support programs written to historical system interfaces. New applications should use siglongjmp() and sigsetjmp() respectively. RATIONALE
None. FUTURE DIRECTIONS
The _longjmp() and _setjmp() functions may be removed in a future version. SEE ALSO
longjmp(), setjmp(), siglongjmp(), 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 Technol- ogy -- 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 Stan- dard 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 _LONGJMP(3P)