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Date: Wed, 23 Apr 2008 03:13:14 -0400
From: "Constantine A. Murenin" <mureninc@gmail.com>
To: "Garrett Cooper" <yanefbsd@gmail.com>
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Cc: hackers@freebsd.org
Subject: Re: strdup(NULL) supposed to create SIGSEGV?
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On 23/04/2008, Garrett Cooper <yanefbsd@gmail.com> wrote:
> Hi all,
>      I made an oops in a program, which uncovered "feature" in strdup(2)
>  that I wasn't aware of before. So I was wondering, is strdup(pointer = NULL)
>  supposed to segfault should this just return NULL and set errno?
>      Good news is that Linux does the same thing (yay?), so at least FreeBSD
>  isn't alone..

strdup(3) duplicates a string, and NULL is obviously not a string.

Or would you expect strlen(NULL) to return 0 and set errno, too? But
then you have to redesign most, if not all, libc string functions
(http://cvsweb.freebsd.org/src/lib/libc/string/), breaking the
expected behaviour of many existing applications and promoting
unportable code.

C.