SETJMP(3) Library functions SETJMP(3)
NAME
setjmp, sigsetjmp - save stack context for non-local goto
SYNOPSIS
#include<setjmp.h>
intsetjmp(jmp_buf env);
intsigsetjmp(sigjmp_buf env,int savesigs);
DESCRIPTION
setjmp() and longjmp() are useful for dealing with errors and inter-
rupts encountered in a low-level subroutine of a program. setjmp()
saves the stack context/environment in env for later use by longjmp().
The stack context will be invalidated if the function which called
setjmp() returns.
sigsetjmp() is similar to setjmp(). If savesigs is nonzero, the set of
blocked signals is saved in env and will be restored if a siglongjmp()
is later performed with this env.
RETURNVALUE
setjmp() and sigsetjmp() return 0 if returning directly, and non-zero
when returning from longjmp() using the saved context.
CONFORMINGTO
POSIX, ISO 9899 (C99)
NOTES
POSIX does not specify whether setjmp will save the signal context. (In
SYSV it will not. In BSD4.3 it will, and there is a function _setjmp
that will not.) If you want to save signal masks, use sigsetjmp.
setjmp() and sigsetjmp make programs hard to understand and maintain.
If possible an alternative should be used.
SEEALSO
longjmp(3), siglongjmp(3)
1997-03-02 SETJMP(3)
Take our 
