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Date: Fri, 17 Jan 2014 05:06:16 +1100
Subject: Re: Guessing the encoding from a BOM
From: Chris Angelico <rosuav@gmail.com>
Cc: "python-list@python.org" <python-list@python.org>
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Xref: csiph.com comp.lang.python:64095

On Fri, Jan 17, 2014 at 5:01 AM, Bj=C3=B6rn Lindqvist <bjourne@gmail.com> w=
rote:
> 2014/1/16 Steven D'Aprano <steve+comp.lang.python@pearwood.info>:
>> def guess_encoding_from_bom(filename, default):
>>     with open(filename, 'rb') as f:
>>         sig =3D f.read(4)
>>     if sig.startswith((b'\xFE\xFF', b'\xFF\xFE')):
>>         return 'utf_16'
>>     elif sig.startswith((b'\x00\x00\xFE\xFF', b'\xFF\xFE\x00\x00')):
>>         return 'utf_32'
>>     else:
>>         return default
>
> You might want to add the utf8 bom too: '\xEF\xBB\xBF'.

I'd actually rather not. It would tempt people to pollute UTF-8 files
with a BOM, which is not necessary unless you are MS Notepad.

ChrisA