What's the most Pythonic way of determining endianness?

python endianness
Major Major picture Major Major · Aug 28, 2009 · Viewed 12.1k times · Source

I'm trying to find the best way of working out whether the machine my code is running on is big-endian or little-endian. I have a solution that works (although I haven't tested it on a big-endian machine) but it seems a bit clunky:

import struct
little_endian = (struct.pack('@h', 1) == struct.pack('<h', 1))

This is just comparing a 'native' two-byte pack to a little-endian pack. Is there a prettier way?

Answer

Scott Griffiths picture Scott Griffiths · Aug 28, 2009

The answer is in the sys module:

>>> import sys
>>> sys.byteorder
'little'

Of course depending on your machine it may return 'big'. Your method should certainly work too though.

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