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Date: Thu, 16 Dec 2004 23:58:51 -0800 (PST)
From: vlobanov <vlobanov@speakeasy.net>
To: Jan Engelhardt <jengelh@linux01.gwdg.de>
cc: Mitchell Blank Jr <mitch@sfgoth.com>,
       krishna <krishna.c@globaledgesoft.com>,
       Linux Kernel <linux-kernel@vger.kernel.org>
Subject: Re: Significance of do ... while (0)
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> >>    Can any one explain the importance of do  ... while (0)
> >
> >It's a standard C programming practice; more info is available from
> >your local search engine:
> >  http://www.google.com/search?lr=&c2coff=1&q=%22while%280%29%22
>
> Why? {} would suffice, no need to do{}while(0)
>
>
>
> Jan Engelhardt
> --
> ENOSPC
> -
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Unless I'm mistaken, it won't work in all cases. Example:

    #define foo(...) { ... /* nefarious macro stuff here */ ... }

    if (some_condition)
        foo();
    else
        // do something nifty

The above would expand to:

    if (some_condition) {
        /* nefarious macro stuff here */
    };
    else
        // do something nifty

And that's not quite right.

-Vadim Lobanov