From owner-freebsd-chat Sat Feb 26 14:32:20 2000 Delivered-To: freebsd-chat@freebsd.org Received: from mail2.x-treme.gr (mail2.x-treme.gr [212.120.196.24]) by hub.freebsd.org (Postfix) with ESMTP id 3808A37B596 for ; Sat, 26 Feb 2000 14:31:40 -0800 (PST) (envelope-from keramida@ceid.upatras.gr) Received: from hades.hell.gr (pat58.x-treme.gr [212.120.197.250]) by mail2.x-treme.gr (8.9.3/8.9.3/IPNG-ADV-ANTISPAM-0.1) with ESMTP id AAA13995; Sun, 27 Feb 2000 00:30:26 +0200 Received: by hades.hell.gr (Postfix, from userid 1001) id 0CBC8DD283; Sat, 26 Feb 2000 23:23:24 +0200 (EET) Date: Sat, 26 Feb 2000 23:23:24 +0200 From: Giorgos Keramidas To: cjclark@home.com Cc: Alfred Perlstein , Marco Molteni , freebsd-chat@FreeBSD.ORG Subject: Re: how to do this C preprocessor trick? Message-ID: <20000226232324.C99617@hades.hell.gr> Reply-To: keramida@ceid.upatras.gr References: <20000225182432.A5017@sofia.csl.sri.com> <20000226001121.A20702@cc942873-a.ewndsr1.nj.home.com> <20000225214616.U21720@fw.wintelcom.net> <20000226003741.C20702@cc942873-a.ewndsr1.nj.home.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 1.0i In-Reply-To: <20000226003741.C20702@cc942873-a.ewndsr1.nj.home.com>; from cjc@cc942873-a.ewndsr1.nj.home.com on Sat, Feb 26, 2000 at 12:37:41AM -0500 X-PGP-Fingerprint: 62 45 D1 C9 26 F9 95 06 D6 21 2A C8 8C 16 C0 8E X-Phone-Number: +30-94-6203692, +30-93-2886457 X-Address: Theodorou Kirinaiou 61, 26334 Patra, Greece Sender: owner-freebsd-chat@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org On Sat, Feb 26, 2000 at 12:37:41AM -0500, Crist J. Clark wrote: > > Why a, > > do { } while(0) > > Rather than just, > > { } > > That's how I group multi-statement macros, but that does not work for > this one. One fairly good reason that I can clearly remember is that, with the extra do { .. } while (0) wrapping, one gets the extra benefit of being able to define properly scoped local variables within the macro body. -- Giorgos Keramidas, < keramida @ ceid . upatras . gr > For my public PGP key: finger keramida@diogenis.ceid.upatras.gr PGP fingerprint, phone and address in the headers of this message. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-chat" in the body of the message