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Possible Duplicate:
How do I convert between big-endian and little-endian values in C++?

I was wondering how you would byte swap a 32-bit word

I have a huge buffer of these words and each of them need to be byte swapping due to endianness.

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user1496413
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2 Answers2

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Either use the functions provided by your OS (cf. Martin Beckett's answer), or alternatively, if you are looking for a way to do this out of interest you may be interested in the following code snippet:

x = (x & 0x0000FFFF) << 16 | (x & 0xFFFF0000) >> 16;
x = (x & 0x00FF00FF) << 8 | (x & 0xFF00FF00) >> 8;
Thomas Russell
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Use htonl / ntohl provided by your OS

Martin Beckett
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    That will only swap bytes if the native format is the reverse of network format. – Mike Seymour Jul 09 '12 at 14:40
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    @MikeSeymour true, but it's most likely that this is what the user needs. Anyone writing some low level non-network order driver is likely to know how to do it anyway. This seemed a good 99% answer – Martin Beckett Jul 09 '12 at 14:41
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    Well actually I am writing a low level non-network order driver... For an internship though so its above my head. I understand the concept but I am used to high level languages. – user1496413 Jul 09 '12 at 16:04