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From: Keith Thompson <kst-u@mib.org>
Newsgroups: comp.lang.c
Subject: Re: NULL as the empty string
Date: Tue, 21 Nov 2017 15:28:10 -0800
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ram@zedat.fu-berlin.de (Stefan Ram) writes:
> jacobnavia <jacob@jacob.remcomp.fr> writes:
>>Whaat would happen if we decide to give meaning to NULL?
>
>   One can do so by
>
> #include <stddef.h>
>
>   .
>
>>strlen would return zero, etc. This way, we would save terabytes of "\0" 
>>strings since an empty string would not require any storage, since it is 
>>empty of course!
>
>   An implementation already is free to map all »""« to the same address.
>
>       »It is unspecified whether these arrays are distinct
>       provided their elements have the appropriate values.«
>
>     6.4.5p7

Yes, but there's a difference between an empty string and an empty
string literal.

This:

    char s[] = "";

creates an empty string.  The address of s won't be the same as the address
of an empty string literal (unless there's some interesting optimization
going on).

[...]

-- 
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"