Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!watmath!clyde!caip!princeton!allegra!ulysses!mhuxr!mhuxn!ihnp4!poseidon!brent
From: brent@poseidon.UUCP (Brent P. Callaghan)
Newsgroups: net.sources
Subject: Re: ifdef filter
Message-ID: <1469@poseidon.UUCP>
Date: Sat, 19-Jul-86 18:19:41 EDT
Article-I.D.: poseidon.1469
Posted: Sat Jul 19 18:19:41 1986
Date-Received: Mon, 21-Jul-86 04:21:06 EDT
References: <323@enmasse.UUCP>
Organization: AT&T Information Systems, Lincroft NJ
Lines: 29

> 
> It often happens that software packages are set up to run on so many
> configurations that it is hard to read the code because of all the ifdefs.
> I would like a filter for C programs that does something like the
> following:
> 
> Invoke it like this:
> 
> 	prog <x.c >x.c.new -DSYSV -D68000
> 
> That is, filter out everything that is not going to be expanded by cpp while
> retaining the ifdefs that are going to be expanded, just for comment value.
> Ideally the output, when compiled, would produce exactly the same results as the
> original.  Does anyone have anything like this?

How about something simple like the following shell/awk one-liner:

          awk "/# *ifdef.*$1/ , /#endif/ {print}" $2

Call it "ifdef" and invoke as:

	  ifdef 6800  x.c  >  x.c.new

-- 
				
Made in New Zealand -->		Brent Callaghan
				AT&T Information Systems, Lincroft, NJ
				{ihnp4|mtuxo|pegasus}!poseidon!brent
				(201) 576-3475