C code line, pointer declaration

This is a discussion on C code line, pointer declaration within the C Programming forums, part of the General Programming Boards category; Hi I don't understand this code line: Code: struct iphdr *iph=(struct iphdr *)data; where data is an u_char. What I ...

  1. #1
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    Post C code line, pointer declaration

    Hi

    I don't understand this code line:
    Code:
    struct iphdr *iph=(struct iphdr *)data;
    where data is an u_char.
    What I can see is that we are creating a pointer (iph) to a iphdr struct, but the right side is not very clear. Can anyone explain the meaning, please?

    Thanks in advance

    Dedalus

  2. #2
    Deathray Engineer MacGyver's Avatar
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    If this example is too difficult to understand, you should get a good C book and learn the basics. The code is casting data to a struct iphdr * and then assigning it to the newly created variable iph.

    BTW, if you mean that data is an unsigned char, then this cast is rather horrible to do and makes little sense to me. In fact, this could be the cause of some ugly problems.

    Oh, and welcome to cboard.
    Last edited by MacGyver; 06-10-2009 at 05:37 AM. Reason: Messed up spelling of type name.

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    Thanks MacGyver

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