From: "Johan Venter" <jventer AT writeme DOT com>
Newsgroups: alt.comp.lang.learn.c-c++,comp.lang.c++,comp.os.msdos.djgpp,comp.os.msdos.programmer
References: <7n6153$eqc$1 AT autumn DOT news DOT rcn DOT net>
Subject: Re: Help with Casts...
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Date: Thu, 22 Jul 1999 14:04:32 +1000
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To: djgpp AT delorie DOT com
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Reply-To: djgpp AT delorie DOT com

Tom wrote in message <7n6153$eqc$1 AT autumn DOT news DOT rcn DOT net>...
>I'm am having trouble understanding casts.  Let's say I want to call a
>program and it takes three variables.  Two of those variables are casts and
>are supposed to return values from what I understand.  How do I get those
>two values.
>
>Example;
>
>int playcdtrack(tracknumber, *startingposition, *endingposition)
>
>How do I get the variables startingposition and endingposition of let's say
>track #1?
>
>If anyone can help I would greatly appreciate.  Thanks.

These are not casts you are talking about, but pointers.
Here's an example:

int a = 10;
int *b = &a;    //b = the address of a, so a = *b and vise versa

Bad example, I know.
In playcdtrack() when referencing the last two variables you should use an asterisk to
reference what the pointer points to, rather than the address the pointer holds, so, quick
example:

void playcdtrack(int tracknumber, int *startingposition, int *endingposition)
{
    *startingposition = find_starting_position_of_track(tracknumber);        //just
example code, use your own code here
    *endingposition = find_ending_position_of_track(tracknumber);
}

int main(void)
{
    int start, end;

    playcdtrack(1, &start, &end);    // & = THE ADDRESS OF

    return 0;
}

I hope I didn't make any mistakes in that code, i'm in a hurry. If I did then I'm going to
be pretty embarressed.

--
Johan Venter
ICQ 3643877
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