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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: Empty functions (was: GCC and const-correctness)
Date: Thu, 11 Oct 2018 10:54:12 -0700
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Keith Thompson <kst-u@mib.org> writes:
[...]
> A null pointer (which doesn't point to a function) is not the same
> as a function that does nothing.

What I meant to say is that a null pointer is not the same as *a pointer
to* a function that does nothing.

>                                   A function that takes a pointer
> to a callback function should document what it does with it.  In my
> opinion it's perfectly reasonable to require the passed pointer to
> be non-null (or perhaps for a null pointer to have some distinct
> meaning).

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"