Thread: Question

  1. #1
    Registered User
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    Question

    Hello everybody,

    Can anybody explain to me what does the following example mean. Or any of you can show me the reference to explain it?

    #define MESSAGE(MID,Respn) (MID = *((unsigned int *)Respn))

    Thanx.

  2. #2
    Sweet
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    That would take two variables and cast respn to an unsigned int pointer and assign the value stored at that address to MID.

    Code:
    unsigned int x = 10;
    unsigned int y = 0;
    
    MESSAGE(x, &y);
    
    printf("%u", x);
    Not a great example but it should work.
    Woop?

  3. #3
    Hurry Slowly vart's Avatar
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    Quote Originally Posted by prog-bman View Post
    That would take two variables and cast respn to an unsigned int pointer and assign the value stored at that address to MID.

    Code:
    unsigned int x = 10;
    unsigned int y = 0;
    
    MESSAGE(x, &y);
    
    printf("%u", x);
    Not a great example but it should work.
    actually more interesting example would be
    Code:
    unsigned int x;
    float y = 2.34;
    
    MESSAGE(x, &y);
    
    printf("%u", x);
    All problems in computer science can be solved by another level of indirection,
    except for the problem of too many layers of indirection.
    David J. Wheeler

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