Passing Pointers

This is a discussion on Passing Pointers within the C Programming forums, part of the General Programming Boards category; Hi, I'm just wondering if this is the correct way to pass a pointer in a for loop: say I ...

  1. #1
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    Passing Pointers

    Hi, I'm just wondering if this is the correct way to pass a pointer in a for loop:

    say I have the following variables. (don't worry about functions not having prototypes etc, this is only an example).

    Code:
    #include <stdio.h>
    
    int *firstPointer;
    int *secondPointer;
    int x = 0;
    int array[5];
    int aFunctionCall();
    
    int main()
    {
    firstPointer = &x; // firstPointer now points to x, x holds the value 0.
    aFunctionCall();
    if (x == 2)
       {
            array[(*firstPointer)-1] = 5; // basically says 'array[2-1] = 5'; aka 'array[1] = 5'
    }
    
    int aFunctionCall()
    for (*firstPointer=1; *firstPointer <= 3; *firstPointer++) // sets the value of x to 1 etc?
    {
         if (*firstPointer == 2) // basically saying if the value of x is 2?
         {
              return 0;
         }
    }

    So basically at the end of this program array[1] will be holding the value 5, if i'm correct :P
    so yeah, hope i didn't confuse everyone too much -_- thanks.
    Last edited by pobri19; 05-26-2008 at 11:10 PM.

  2. #2
    Woof, woof! zacs7's Avatar
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    Where did 'a' come from?

  3. #3
    C++ Witch laserlight's Avatar
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    No, it is not good since it unnecessarily relies on global variables. Also, a is never declared. Honestly, if you want to give a code example, give one that works, or that you did your best to try and get it to work.
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  4. #4
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    Uh I just wrote that from the top of my head, and it's not really necessary because i'm not asking if the code is right, i'm asking if the idea is right.. sorry if i left something out :>

    EDIT: gah sorry, i got a bit confused, a is meant to be *firstPointer, i'm trying to compare this off something i've already written and it's using different variable names etc. ill fix it up.

    I think it's all fixed now, sorry.
    Last edited by pobri19; 05-26-2008 at 11:11 PM.

  5. #5
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    Then yes, at the end of your program array[1] will be set to 5. What exactly is your question..?

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