C compiler for IBM (MVS & CMS)

[Alan Crosswell]

WATCOM Products, Inc. (The University of Waterloo spin-off) has done a nice
job on a CMS C compiler.  The license fee is reasonable and I found it to be
much nicer than Oracle, Whitesmiths, or ATT's C/370.  As usual,  the Waterloo
folks have done a good job.  You can call (519) 886-3700 or write to
	WATCOM Products, Inc.
	415 Phillip Street
	Waterloo, Ontario N2L 3X2
	Canada
Waterloo C does not provide a "fortran" linkage by just declaring an external
function as type fortran but you can write a 10 line assembly interface that
maps from their linkage to OS linkage for example.  They provide an example
subroutine that does just this in the manual.  Whether you can get this to
work with PL/I or Fortran subroutines really depends.  I would say that if
you know the junk required to write an Assembler main program that can call a
PL/I or Fortran subroutine then you would be able to do it in Waterloo C
(with some Assembler).  The converse situation:  calling a C function from
PL/I or Fortran is definitely doable.  I have done something along these
lines already where I call a C function as a second-level CMS interrupt 
handler.  The first-level handler is an assembler routine that sets up 
the C environment (stack and registers).  Again,  the information I needed
to set up the environment was in the Waterloo documentation.

Alan Crosswell
Columbia University Center for Computing Activities

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