Used for establishing an OpenVMS exception handler for a
    particular routine. This function establishes a special C RTL
    exception handler in the routine that called it. This special
    handler catches all RTL-related exceptions that occur in later
    routines, and passes on all other exceptions to your handler.

    Format

      #include  <signal.h>

      void VAXC$ESTABLISH  (unsigned int (*exception_handler)(void
                           *sigarr, void *mecharr));