Des. Port & Src. Port Verification Method!

This is a discussion on Des. Port & Src. Port Verification Method! within the C Programming forums, part of the General Programming Boards category; Hi there, I'm trying to check on the value of two variables dst_port & src_port if any of them is ...

  1. #1
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    Des. Port & Src. Port Verification Method!

    Hi there,

    I'm trying to check on the value of two variables dst_port & src_port if any of them is 23 then service=the one who has that value.
    so,let take this example1;

    dst_port = 23;
    src_port= 2000;

    then service=dsp_port;

    other example;
    dst_port = 2000;
    src_port= 23;

    then service=src_port;

    I'm thinking of using bitwis operations, but not clear how yet.

    Any clue ??

  2. #2
    Gawking at stupidity
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    service = dst_port == 23 ? dst_port : src_port == 23 ? src_port : 0;

    Note that that only sets service to 23 or 0. You don't know which variable it got the 23 from though. You could do it like this instead though:

    int *service = dst_port == 23 ? &dst_port : src_port == 23 ? &src_port : NULL;

    Then service will be a pointer to the correct port if that's important to you. In either case, service will be 0 (or NULL if you go with the second code snippet) if neither one of them was 23.

  3. #3
    Registered User
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    Why not
    Code:
    if ((dst_port == 23) || (src_port == 23)) {
      service = 23;
    }
    I don't think bit-wise operations are the way to go in this case
    DavT
    -----------------------------------------------

  4. #4
    Obsessed with C chrismiceli's Avatar
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    Quote Originally Posted by DavT
    Why not
    I don't think bit-wise operations are the way to go in this case
    What bitwise operations, if you are referring to the logical or (||), you are wrong.
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