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Mail Archives: djgpp/2000/04/30/03:44:24

From: Nate Eldredge <neldredge AT hmc DOT edu>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Array swapping.
Date: 30 Apr 2000 00:58:55 -0700
Organization: InterWorld Communications
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Krogg <krogg DOT no DOT to DOT spam AT gtcom DOT net> writes:

> Joseph Rose wrote:
> > 
> > Try:
> > 
> > void Swap (void* A, void* B)
> > {
> >     void* i=A
> >     A=B
> >     B=i
> >     return;
> > }
> 
> Just for fun i tried this.
[snip]
> This is the output:
> 59.720001
> 0.000000
> 
> so,IT DON'T WERK........
>  
> 
> The real problem in this is that i need to 
> change the value of a constant pointer...
> 
> There has to be a way to do this.

The solution is to make it not constant.  Instead of `float
foo[40][50]', you could do:

float (*foo)[50];
foo = malloc(40 * sizeof(*foo));

You can then throw the pointers around as desired.

This should probably go to comp.lang.c, since there's nothing
DJGPP-specific about it, but oh well.

-- 

Nate Eldredge
neldredge AT hmc DOT edu

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