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From:   Florian Weimer <fw@deneb.enyo.de>
To:     Jonny Grant <jg@jguk.org>
Cc:     linux-man <linux-man@vger.kernel.org>,
        Michael Kerrisk <mtk.manpages@gmail.com>
Subject: Re: strlen
References: <0bf239e9-cfc7-8889-ca00-b1d1566bd174@jguk.org>
Date:   Fri, 04 Sep 2020 21:21:47 +0200
In-Reply-To: <0bf239e9-cfc7-8889-ca00-b1d1566bd174@jguk.org> (Jonny Grant's
        message of "Fri, 4 Sep 2020 19:01:12 +0100")
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* Jonny Grant:

> Hello
>
> https://man7.org/linux/man-pages/man3/strlen.3.html
>
> Is it possible to clarify :-
>
> * glibc will SIGSEGV if 's' is NULL
> * there are no ERROR returns

That would be misleading.  Whether strlen (NULL) is undefined also
depends on the compiler.  They know that the argument cannot be zero
and optimize accordingly.