Thread: what to do with unused array elements

  1. #1
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    Question what to do with unused array elements

    Hello,

    I have some arrays in my code which will contain different messages of varying lengths, so I have sized my arrays to take the longest ones (plus 1 or two elements on the end), but how do I ensure that if the message is shorter than maximum, there is not junk in the unused elements which would be sent out my serial port?

    Thanks
    Dave

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    before filling the value in your array just
    Code:
    memset(array, 0,  sizeof(size) * MAX_NUMBER)
    and initailize your array like
    Code:
    array[MAX_NUMBER] = {0}

  3. #3
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    The third argument to memset is computed like (sizeof(array[0]) * MAX_NUMBER), because the function expects a number of bytes.

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    Thanks for that info Rocky, that sounds like just what I need. Just to clarify, I invoke this function when I am declaring my arrays? Also, can I insert this code into a struct member declaration, or would I have to declare my arrays separately first?

    --dave
    Last edited by droseman; 11-05-2009 at 06:14 AM. Reason: extra info

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    You are most welcome Enjoy C/C++ programming

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