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From: "Stephen J. Turnbull" <turnbull AT sk DOT tsukuba DOT ac DOT jp>
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Subject: Re: _CRT0_FLAG_NULLOK
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Date: Wed, 31 Jul 2013 22:45:14 +0900
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Rod Pemberton writes:

 > > It is not possible to give a consistent specification of what
 > > happens when NULL is passed to a function,

"Consistent" may be a bad word, but my point is that (pointer to char)
and (NULL) have very different semantics.  The memory referenced by
the latter can be neither accessed nor mutated, so no computations can
be done with it.  In order to associate an array of chars with NULL,
you need to make an arbitrary decision.

 > It sure is _possible_.  It just wasn't done.  That's entirely
 > different than actually *not* being able to specify something.

Of course it's possible to specify "something".  It's just not
possible to infer that something from the behavior of the function
when passed a non-NULL char*.