From: Erik Max Francis <max AT alcyone DOT com>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Dynamically declaring 2-d arrays
Date: Sat, 14 Feb 1998 12:06:50 -0800
Organization: Alcyone Systems
Lines: 33
Message-ID: <34E5F95A.793B45C4@alcyone.com>
References: <34DF9744 DOT C7CFDBFE AT ea DOT oac DOT uci DOT edu> <6c3ulo$jq AT freenet-news DOT carleton DOT ca>
NNTP-Posting-Host: 165.90.20.242
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp
Precedence: bulk

Paul Derbyshire wrote:

> My dynamic 2D array recipe:
> 
> int (*foo)[ysize] = malloc (xsize*ysize*sizeof(int));

This only wroks if ysize is not a variable, i.e., it is not truly
dynamic.

gcc has extensions to allow variable-sized arrays, but they are
gcc-specific.

> As for C++, it ought to be possible (at least with gnu) to use
> 
> foo = new int[y][x];
> /* ... */
> delete [] foo;
> 
> (is it?)

Same restriction applies here.

In general, it's a bad idea to use any compiler extensions unless you
have a _very_ good reason, or know for a fact you'll never have to/want
to port the program to another compiler/platform.

-- 
         Erik Max Francis, &tSftDotIotE / mailto:max AT alcyone DOT com
                       Alcyone Systems / http://www.alcyone.com/max/
  San Jose, California, United States / icbm://+37.20.07/-121.53.38
                                     \
                       "Life may be / the product of imperfections."
                                   / (Marclo Gleiser)