Please note that since the initial release of the program, I've added the ability to specify a word size with -w. So if you're on a machine with 11 byte words, you can swap ABCDEFGHIJK to KJIHGFEDCBA .
The program verifies that your file's length is a multiple of your selected wordsize, and attempts to give a progress report so you have a feel for how long the conversion is going to take (but only if the input is fstat()'able, which generally means files, but not pipes).
byte-swap is more likely to handle a file full of integers, than a file
full of real's - but it can sometimes handle real's as well, or a file
full of mixed-but-same-sized integers and reals, depending on what
platforms are involved. If your file has character/string data in it,
then byte-swap is likely to make a mess of that information.
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