SETJMP(3)                                               SETJMP(3)

     NAME
          setjmp, longjmp - non-local goto

     SYNOPSIS
          #include <setjmp.h>

          setjmp(env)
          jmp_buf env;

          longjmp(env, val)
          jmp_buf env;

     DESCRIPTION
          These routines are useful for dealing with errors and inter-
          rupts 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 contin-
          ues 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 val-
          ues as of the time longjmp was called.

     SEE ALSO
          signal(2)