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From:   "Michael Kerrisk (man-pages)" <mtk.manpages@gmail.com>
Date:   Tue, 29 Sep 2020 15:38:03 +0200
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Subject: Re: [PATCH 12/24] getgrent_r.3: Use sizeof() to get buffer size
 (instead of hardcoding macro name)
To:     Alejandro Colomar <colomar.6.4.3@gmail.com>
Cc:     Stefan Puiu <stefan.puiu@gmail.com>,
        lnx-man <linux-man@vger.kernel.org>,
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> 2.-     Use sizeof() everywhere, and the macro for the initializer.
>
> pros:
> - It is valid as long as the buffer is an array.
> cons:
> - If the code gets into a function, and the buffer is then a pointer,
>    it will definitively produce a silent bug.

Sigh! I just did exactly the last point in a test program I've been writing...

M