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From: jgk@panix.com (Joe keane)
Newsgroups: comp.lang.c
Subject: Re: possible NULL && dereferencing NULL pointer
Date: Wed, 1 Feb 2012 15:15:24 +0000 (UTC)
Organization: Public Access Networks Corp.
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In article <jg7srm$ka8$1@speranza.aioe.org>,
Mark <mark_cruzNOTFORSPAM@hotmail.com> wrote:
>I'm not sure that memcmp() will not fail if p_master->bridge is NULL (i.e. 
>dereferencing NULL pointer), would it be more clear and correct to have:

In general, you don't pass NULL to a function that takes 'pointer to
so-and-so object', unless you have good evidence that it's allowed, and
it does what you want.

Otherwise, it will
    a) crash,
or
    b) do not what you want.

The 'strcmp' example is good.  What does a NULL argument mean?  Is it
the same thing as the string ""?  Or are NULL and "" two different
things?  Does NULL compare equal to "NULL"?