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From: obrien@cs.ucdavis.edu (David E. O'Brien)
Message-Id: <9601100805.AA19304@toadflax.cs.ucdavis.edu>
Subject: Re: Differentiating between 2.0 and 2.1
To: dglo@SSEC.WISC.EDU (Dave Glowacki)
Date: Wed, 10 Jan 1996 00:05:18 -0800 (PST)
Cc: ports@FreeBSD.ORG
In-Reply-To: <199601100205.UAA03363@tick.SSEC.WISC.EDU> from "Dave Glowacki" at Jan 9, 96 08:05:56 pm
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> 
> OK, I can determine that I'm on a FreeBSD system if __FreeBSD__ is defined
> and I can tell that I'm on a FreeBSD 2.x system if __FreeBSD__ == 2.
> 
> Is there a way to determine if a program is being built on a FreeBSD 2.1
> system as opposed to a 2.0 system?
> 

I believe you could include osreldate.h.  Inside there is 
#define __FreeBSD_version 199511

I believe this to be read "November 1995".

-- David   (obrien@cs.ucdavis.edu)