Detecting if a file is binary

Detecting if a file is binary

[Nordlöw]

Is there a way in emacs-lisp code to detect if a file binary, that is
it does *not* contain a correct multi-character coding.
Or can every possible combination of bytes always be correctly decoded
by some character coding?

/Nordlöw

Re: Detecting if a file is binary

[tomas]

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On Tue, Nov 24, 2009 at 07:23:34AM -0800, Nordlöw wrote:
> Is there a way in emacs-lisp code to detect if a file binary, that is
> it does *not* contain a correct multi-character coding.
> Or can every possible combination of bytes always be correctly decoded
> by some character coding?

Yes, it can. For all one-byte encodings of the iso-8859-x family, each
byte represents a valid code point, for example. In utf-8 there are byte
sequences which can't (shouldn't) happen.

I think the only way to gain some confidence is by statistical analysis
of the text.

Regards
- -- tomás
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