Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!ists!stpl!bbm!darcy
From: darcy@bbm.UUCP (D'Arcy Cain)
Newsgroups: comp.lang.c
Subject: Re: Nested Macros
Message-ID: <819@bbm.UUCP>
Date: 22 Nov 89 21:15:13 GMT
References: <gZO1Sce00W0JQ6AKEr@andrew.cmu.edu>
Reply-To: darcy@druid.UUCP (darcy)
Organization: BBM Bureau of Measurement, Toronto
Lines: 23

In article <gZO1Sce00W0JQ6AKEr@andrew.cmu.edu> 
jb3o+@andrew.cmu.edu (Jon Allen Boone) writes:
>#define DEBUG 1
>
>#define DB(X) #ifdef (DEBUG) printf(X)
>

I would have coded the above  as follows just because I don't like
smart-alecky code (or more accurately I'm afraid some compiler won't :-).)

#ifdef DEBUG
#define DB(X) printf(X)
#else
#define DB(X)

This however still has the problem that printf has a variable number of
arguments so you  have to call it like this:

    DB(("Error: Result code is %d\n", res));   /* note double parentheses */

and that is probably your error.

D'Arcy