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From: dave@cs.arizona.edu (Dave P. Schaumann)
Newsgroups: comp.lang.c
Subject: Re: Malloc and arrays...
Message-ID: <999@caslon.cs.arizona.edu>
Date: 3 Mar 91 18:12:12 GMT
References: <1991Mar3.172942.3116@nntp-server.caltech.edu>
Organization: U of Arizona CS Dept, Tucson
Lines: 32

In article <1991Mar3.172942.3116@nntp-server.caltech.edu> eychaner@suncub.bbso.caltech.edu writes:
>Warm up those flame guns!  It's time for Another Novice Question!
>
>I know this is partly covered in the FAQ, but it didn't seem to have quite
>the answer I want.
>[...]
>  bigmemory = (char *) malloc (OODLES_O_BYTES);
>I can access the chunk of memory as though it were an array, like so:
>  bigmemory [RIGHT_HERE] = SOME_CHARACTER;
>[becomes]
>  *(bigmemory + RIGHT_HERE) = SOME_CHARACTER;

Right.

>  bigmemory [RIGHT_HERE][RIGHT_NOW] = SOME_CHARACTER;

/* This requires that OODLES_O_BYTES is divisible by NUMBER_OF_ENTRIES_WANTED.
*/
char **two_d = malloc(NUMBER_OF_ENTRIES_WANTED * sizeof(char *))

  for( i = 0 ; i < NUMBER_OF_ENTRIES_WANTED ; i++ )
    two_d[i] = &bigmemory[ i * OODLES_O_BYTES / NUMBER_OF_ENTRIES_WANTED ]

Now you can say two_d[RIGHT_HERE][RIGHT_NOW] = SOME_CHARACTER
Provided I haven't made an Incredibly Stupid Mistake (TM), you should be
able to modify this to your needs.

-- 
		Dave Schaumann		dave@cs.arizona.edu
'Dog Gang'!  Where do they get off calling us the 'Dog Gang'?  I'm beginning to
think the party's over.  I'm beginning to think maybe we don't need a dog.  Or
maybe we need a *new* dog.  Or maybe we need a *cat*! - Amazing Stories