Predefined Names

     The following names have special meaning to perl.   I  could
     have used alphabetic symbols for some of these, but I didn't
     want to  take  the  chance  that  someone  would  say  reset
     "a-zA-Z"  and wipe them all out.  You'll just have to suffer
     along  with  these  silly  symbols.   Most  of   them   have
     reasonable mnemonics, or analogues in one of the shells.