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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:	Thu, 01 Aug 2013 19:04:45 +0900
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Rod Pemberton writes:

 > E.g., [C definition committees] could've specified a NULL pointer
 > always points to an emtpy string of just a null character.  Such a
 > specification is unlikely to break C, since a NULL pointer just
 > needs to have a unique address.  This would've allowed a NULL
 > pointer to safely function as an empty character string too.

Which is an arbitrary decision, because it could be a pointer to an
arbitrary instance of *any* type.  Of course some of those instances
may be compatible with an empty string, but I don't see how you can
guarantee they *all* will be, on all machines you might want to target
with a C compiler.  Even if you restrict them to be "do nothing"
instances.  (Eg, the numeric types have *two* do-nothing instances, 0
and 1, depending on the operation.)  So the decision to favor strings
is arbitrary.

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