Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.2 9/18/84; site osiris.UUCP
Path: utzoo!linus!philabs!cmcl2!seismo!umcp-cs!aplcen!osiris!phil
From: phil@osiris.UUCP (Philip Kos)
Newsgroups: net.wanted.sources
Subject: partial preprocessing
Message-ID: <605@osiris.UUCP>
Date: Thu, 21-Nov-85 11:06:39 EST
Article-I.D.: osiris.605
Posted: Thu Nov 21 11:06:39 1985
Date-Received: Sat, 23-Nov-85 10:23:38 EST
Distribution: na
Organization: Johns Hopkins Hospital
Lines: 34

I'm looking for a way to do partial preprocessing of C programs.  What
I'm talking about is selectively #defining one (or more) preprocessor
variables or macros in the source code and expanding it (them) while
leaving all others untouched.  I want any occurrences of the variables
or macros in the source code (and particularly #if/#ifdef code) to be
expanded.

Is there a way to do this using cpp that I've been missing?  If not,
could m4 do something like this?  (It would have to imitate the Reiser
cpp to perform correctly, so I have my doubts about m4...)  If none of
the preprocessors can handle it, is there a program anywhere which
implements this function?

We have something here on our Pyramid called 'unifdef', which is
located in /usr/ucb and seems to be from Berkeley (according to the
sccs header).  I can't find any documentation on it, though.  If this
*is* an official BSD distribution-type command, could somebody please
explain to me how it works (or at least what it does) - I don't really
have the time to figure it out empirically.

If I get no leads from this posting, I may well write something like
this myself (whenever I manage to find the time!!).  If I do, would
anybody else out there be interested in a copy?



Phil Kos					"Woo!"
The Johns Hopkins Hospital			     -  Trent Phlooog
Baltimore, MD
			   ...!gamma!cp1
				 v
...!decvax!decuac   ->	!aplvax!osiris!phil  <-  ...!unc!brl-bmd
				 ^
			...!allegra!umcp-cs