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From: throopw@xyzzy.UUCP (Wayne A. Throop)
Newsgroups: comp.lang.c
Subject: Re: static char (*b)[6]; /* an unusual declaration */
Message-ID: <116@xyzzy.UUCP>
Date: Sat, 27-Jun-87 13:40:23 EDT
Article-I.D.: xyzzy.116
Posted: Sat Jun 27 13:40:23 1987
Date-Received: Sun, 28-Jun-87 04:47:26 EDT
References: <761@bsu-cs.UUCP> <2117@dg_rtp.UUCP> <207@sugar.UUCP>
Organization: Data General, RTP NC.
Lines: 34

> peter@sugar.UUCP (Peter DaSilva)     
>> throopw@xyzzy.UUCP (Wayne Throop)
>>   [ static char (*b)[6];    is a  ]
>> Static pointer to an array of six characters.  The same memory layout
>> (though *not* the same type) can be had by the declarations:
>>         char q[6];
>>         static char *r = q;
> except that static char (*b)[6] doesn't actually allocate the 6 bytes.

Well, now, I had already said this in the text immediately following,
which Peter removed.  To quote myself:

   Note that the array of characters in the first example does
   *not* have static scope (and is in fact not even allocated).

> Better would be
>   typedef char mytype[6];
>   static mytype *b;

But this misses the entire point.  Peter has defined a type that is
exactly the same as the original declaration of b with type 
(char (*)[6]).  The point was to show that a simple (char *) could
indicate the same memory layout, while (obviously) not being the same
type.  Again, the typedef just above does indeed indicate the same
memory layout.  But it is *exactly* the same type, and does nothing to
clarify the standard confusion, in particular the erronious opinion that
(char **) and (char (*)[6]) indicate the same memory structure.  It is
important to note that they do NOT.

--
Adam and Eve had many advantages, but the principal one
was, that they escaped teething.
                --- Pudd'nhead Wilson's Calendar (Mark Twain)
-- 
Wayne Throop      <the-known-world>!mcnc!rti!xyzzy!throopw