The Decode Instruction Stream During Fault routine is a tool
    for building condition handlers that process instruction fault
    exceptions. It is called from a condition handler.

    This routine is not available to native OpenVMS Alpha and I64
    programs but is available to translated VAX images.

    Format

      LIB$DECODE_FAULT  signal-arguments ,mechanism-arguments

                        ,user-procedure [,unspecified-user-argument]

                        [,instruction-definitions]