_longjmp, _setjmp - non-local goto
void _longjmp(jmp_buf env, int val);
int _setjmp(jmp_buf env);
The _longjmp() and _setjmp() functions are identical to
longjmp(3C) and setjmp(3C), respectively, with the addi-
tional restriction that _longjmp() and _setjmp() do not
manipulate the signal mask.
If _longjmp() is called even though env was never initial-
ized by a call to _setjmp(), or when the last such call was
in a function that has since returned, the results are unde-
Refer to longjmp(3C) and setjmp(3C).
No errors are defined.
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 tem-
porary 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 sup-
port programs written to historical system interfaces. New
applications should use siglongjmp(3C) and sigsetjmp(3C)
longjmp(3C), setjmp(3C), siglongjmp(3C), sigsetjmp(3C)
Man(1) output converted with