What's the most Pythonic way of determining endianness?

Question

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?

Rattrap

Why do you need to know? Your solution seems good enough, but you certainly don't have to know when using 'struct' itself? – Frangos

True, but I'm not using the struct module (perhaps I should be, but I'm not the original author of the code I'm fixing). – Rattrap

Answer 1

The answer is sys module's attribute sys.byteorder:

An indicator of the native byte order. This will have the value 'big' on big-endian (most-significant byte first) platforms, and 'little' on little-endian (least-significant byte first) platforms.

Example:

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

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

Leeway