SETJMP(3)                            BSD                             SETJMP(3)



NAME
     setjmp, longjmp - non-local goto

SYNOPSIS
     #include <setjmp.h>

     setjmp(env)
     jmp_buf env;

     longjmp(env, val)
     jmp_buf env;

     _setjmp(env)
     jmp_buf env;

     _longjmp(env, val)
     jmp_buf env;

DESCRIPTION
     These routines are useful for dealing with errors and interrupts
     encountered in a low-level subroutine of a program.

     setjmp saves its stack environment in env for later use by longjmp. It
     returns value 0.

     longjmp restores the environment saved by the last call of setjmp.  It
     then returns in such a way that execution continues as if the call of
     setjmp had just returned the value val to the function that invoked
     setjmp, which must not itself have returned in the interim.  All
     accessible data have values as of the time longjmp was called.

     setjmp and longjmp save and restore the signal mask sigmask(2), while
     _setjmp and _longjmp manipulate only the C stack and registers.

SEE ALSO
     sigvec(2), sigstack(2), signal(3)