/* System Data Page */

  dcl sysdat$pointer pointer;
  dcl sysdat$ptr structure(
    offset word,
    segment word) at (@sysdat$pointer);
  declare sd based sysdat$pointer structure (
      supmod (4) word,
  /*  rtmmod (4) word,
      memmod (4) word,
      ciomod (4) word,
      bdosmod (4) word,
      xiosmod (4) word,
      netmod (4) word,
      reservd (4) word */
      space1(28) word,
      mpmseg word,
      rspseg word,
      endseg word,
      module$map byte,
      ncns byte,
      nlst byte,
      nccb byte,
      nflags byte,
      srchdisk byte,
      mmp word,
      nslaves byte,
      dayfile byte,
      tempdisk byte,
      tickspersec byte, 
      lul word, 
      ccb word,
      flags word,
      mdul word,
      mfl word,
      pul word,
      qul word,
      qmau (4) word,
      rlr word,
      dlr word,
      drl word,
      plr word,
      slr word,
      thrdrt word,
      qlr word,
      mal word,      
      version word,
      vernum word,
      mpmvernum word,
      tod_day word,
      tod (3) byte,
      ncondev byte,
      nlstdev byte,
      nciodev byte,
      lcb word,
      openvec word,
      lockmax byte,
      openmax byte,
      space2 (2) word,
      cmod byte );	
      
      
declare sd$byte based sysdat$pointer (1) byte;
dcl   ncondev lit '83h',
      nlstdev lit '84h',
      nciodev lit '85h';