The Revert to the Handler of the Routine Activator routine
    deletes the condition handler established by LIB$ESTABLISH by
    clearing the address pointing to the condition handler from the
    activated routine's stack frame.

    This routine is not available to native OpenVMS Alpha and I64
    programs but is recognized and handled appropriately by most HP
    high-level language compilers.

    Format

      LIB$REVERT

1 - Returns

    OpenVMS usage:address
    type:         address
    access:       write only
    mechanism:    by value

    Previous contents of SF$A_HANDLER (longword 0) of the caller's
    stack frame. This is the address of the condition handler
    previously in effect. If no condition handler was in effect,
    zero is returned.

2 - Arguments

    None.