Arrays and pointers

This is a discussion on Arrays and pointers within the C Programming forums, part of the General Programming Boards category; If I am reading an array from a pointer, how can I get the first element of array: Right now ...

  1. #1
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    Arrays and pointers

    If I am reading an array from a pointer, how can I get the first element of array: Right now the following code gets me reading an array of 500 intergers 100 at a time. What if I want to make the first element of my array the sizeof(int). I guess thats a better way to word that question?
    Code:
    File *fptr
    int data[500]
    fptr = (fopen("xfile.dat", "rb");
    for (i=0, i<500, i +=100)
     fread(&data[i], sizeof(int),100),fptr)
    Right now I am declaring the array size of 500 but if I want to put in my array first element can I declare &data[0] and make it equal to size of int or do I have to take i when its at 0 and use it for my sizeof int.

  2. #2
    and the Hat of Guessing tabstop's Avatar
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    Are you saying that the first number on your list is the number of numbers to go in the array? Or what?

    sizeof(int) is not something about your program, it's something about your machine (how much space does an int take on this particular piece of silicon).

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