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    <p>Yes, that's exactly what <code>fwrite()</code> is. It uses a <code>const void *</code> which means "pointer to any type of data", and treats it as a pointer to bytes.</p> <p>So, your wrapper isn't really needed, you can just make a correctly-sized call to <code>fwrite()</code> right away to write the array:</p> <pre><code>const int my_ints[3] = { 1, 2, 3 }; const double my_doubles[5] = { 5, 4, 3, 2, 1 }; fwrite(my_ints, sizeof *my_ints, sizeof my_ints / sizeof *my_ints, stdout); fwrite(my_doubles, sizeof *my_doubles, sizeof my_doubles / sizeof *my_doubles, stdout); </code></pre> <p>Note that writing binary data to <code>stdout</code> can be somewhat rude, and also that I/O calls should be checked for errors.</p> <p>If you drop the "x elements of y bytes" model that <code>fwrite()</code>'s API uses, and just treat them as single chunks of bytes, you can simplify the calls:</p> <pre><code>fwrite(my_ints, sizeof my_ints, 1, stdout); fwrite(my_doubles, sizeof my_doubles, 1, stdout); </code></pre> <p>Note that there's no point in looping, the numbers in each array will be adjacent in memory so <code>fwrite()</code> can write them all at once. It's generally best to keep the number of I/O calls done down as much as possible, so if you can do a single write of <code>n * m</code> bytes instead of <code>n</code> writes of <code>m</code> bytes each, that's almost often better. Remember that that many of the underlying devices that you write to are block-oriented, and will benefit a lot from getting whole blocks of data since that's what they have to write, anyway.</p>
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    1. POCan I create a function which accepts a pointer to an array which may contain a different type of numbers on each call?
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    1. COVery happy but almost too cynical to believe it could be that simple :) - I do need the wrapper though, for other reasons (particular headers need to be included to define the dimensions in the array for other programs reading the file, etc.)
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    2. COQuestion: I guess fwrite doesn't need the loop because it handles buffering itself - the main reason for the loop was to write in chunks for speed. Do you know if this is a safe assumption across Linux builds and compilers?
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