[PATCH 1/3] dix: Add facilities for client ID tracking.

Alan Coopersmith alan.coopersmith at oracle.com
Mon Aug 30 22:26:14 PDT 2010


Vignatti Tiago (Nokia-MS/Helsinki) wrote:
>> +#ifndef CLIENT_IDS_H
>> +#define CLIENT_IDS_H
> 
> does anyone knows if these macros on the top of header files are useful for
> some reason? I don't think so.

They prevent errors about redefined types/macros if the file gets included twice
for some reason - they're a very common C idiom, required in many projects for
good reason.  See http://en.wikipedia.org/wiki/Include_guard for a basic
explanation - I'm sure google can find much more to educate you about them.

-- 
	-Alan Coopersmith-        alan.coopersmith at oracle.com
	 Oracle Solaris Platform Engineering: X Window System



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