Date   : Wed, 12 Jun 1991 21:15:38 -0400 (EDT)
From   : John C Klensin <KLENSIN@INFOODS.MIT.EDU>
Subject: PL/I and PL/M and PL/??

David Douthitt writes...

>Isn't that really PL/M?  Of course, that might be all that's needed.
>PL/M is PL/I for [M]icros.  
   Well, no.  More like "Programming Language / Micros".  It shares some
syntax with PL/I, but not even enough to be considered a dialect.  
Digital Research "PL/I" (not to be confused with PL/I) really is a 
dialect.

>Anyone got a handle on what PL/C was supposed to be?
  The appearance of PL/I in the marketplace, and its tenure as the 
teaching language of choice, was associated with a largish collection of 
PL/I dialects and PL/I-like languages designed for various purposes or 
to illustrate various points.
  PL/C was a pedagogical subset that came out of Cornell (ok, now guess 
what the "C" stands for).  It lacked, among other things, BASED 
variables and pointers, which put in into the class known at the time as 
"FORTRAN with semicolons" rather than serious PL/I.
  A certain large computer manufacturer had a variation for systems 
programming work (more control of registers, etc.) that, for a while, 
was called PL/S but which was never released to customers and, as far as 
I know, never officially existed.
  There was also, if I recollect correctly (it has been a LONG time, he 
says, pulling at his white beard), one collection of PL/I dialects and
variants that were not named PL/x but SP/1 ... SP/K.  The came, if I
recall, out of Toronto.  If one could find the sources somewhere, it
might be pretty easy to put them up in a micro environment. 
   --john
   Klensin@INFOODS.MIT.EDU