_LONGJMP(3C) Standard C Library Functions _LONGJMP(3C)
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 are identical to
longjmp(3C) and
setjmp(3C), respectively, with the additional restriction that
_longjmp() and
_setjmp() do 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 VALUES
Refer to
longjmp(3C) and
setjmp(3C).
ERRORS
No errors are defined.
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 termination. 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(3C) a pointer to a buffer not created by
sigsetjmp(3C) 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(3C) and
sigsetjmp(3C) respectively.
ATTRIBUTES
See
attributes(7) for descriptions of the following attributes:
+--------------------+-----------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-----------------+
|Interface Stability | Standard |
+--------------------+-----------------+
SEE ALSO
longjmp(3C),
setjmp(3C),
siglongjmp(3C),
sigsetjmp(3C),
attributes(7),
standards(7) July 24, 2002 _
LONGJMP(3C)