Path: utzoo!utgpu!jarvis.csri.toronto.edu!clyde.concordia.ca!uunet!aussie!rex
From: rex@aussie.UUCP (Rex Jaeschke)
Newsgroups: comp.std.c
Subject: Re: A simple typing question.
Message-ID: <36.UUL1.3#5077@aussie.UUCP>
Date: 13 Feb 90 16:39:16 GMT
References: <25D7D0BE.17645@paris.ics.uci.edu>
Organization: Journal of C Language Translation
Lines: 33

> Ronald Guilmette writes:

> The question really is: "What is the type of a?"  Is the type of `a'
> simply `int *' or is it `int * const'?
> 
> */
> 
> int *p;
> 
> void function (int a[])
> {
>   a = p;
> }

In the scope of a definition (or an extern declaration) of an array,
the array name IS a const pointer.  Not so though when used as a 
formal parameter. At that stage arrays and pointers are synonymous. In 
fact ANSI C requires that arguments be passed by value and that a 
private MODIFIABLE copy be made available to the called function. As 
such, a++ is valid inside function above. If, however, the formal 
parmeter were declared as (int * const a) then a would be a const 
pointer. (I don't see how to declare as such using array notation 
though since const int a[] is NOT the same thing.)

Rex

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