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Mail Archives: cygwin/1998/05/13/00:44:32

From: rhg AT cps DOT com (Richard H. Gumpertz)
Subject: Re: strlen on a NULL
13 May 1998 00:44:32 -0700 :
Message-ID: <199805121632.LAA18276.cygnus.gnu-win32@Pooh.cps.com>
References: <3557E6C4 DOT EF2F27B3 AT kiwiplan DOT co DOT nz>
To: ian AT kiwiplan DOT co DOT nz (Ian Collins)
Cc: gnu-win32 AT cygnus DOT com

> If I do a strlen on a NULL pointer I get a coredump.
> I have the same code running on a few *other* Unix machines with
> exhibiting this behaviour.
> OK, so I could tidy it up, but I wondered is this an oversight or the
> correct behaviour?

Sounds like correct behavior to me.  The result of using strlen (or any other
function that indirects through a pointer and does not explicitly define
behavior for NULL) is undefined and therefore implementation dependent.  The
most reasonable behavior for a strlen implementation is probably to do
whatever makes the WELL-DEFINED uses of strlen as fast as possible.

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