SETJMP (3)
save stack context for non-local goto
SYNOPSIS
int setjmp(jmp_buf env );
int sigsetjmp(sigjmp_buf env , int savesigs );
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DESCRIPTION
setjmp() and longjmp() are useful for dealing with errors
and interrupts 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.
RETURN VALUE
setjmp() and sigsetjmp() return 0 if returning directly, and
non-zero when returning from longjmp() using the saved context.
CONFORMING TO
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.
SEE ALSO
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