bug#20891: emacs: Back off if .doc is not an Office document

[Stefan Kangas]

Lars Ingebrigtsen <larsi@gnus.org> writes:

> era+emacs@iki.fi writes:
>
>> It is not uncommon for *.doc files to contain plain ASCII text. In this
>> case, the default behavior of Emacs is less than ideal, as described in
>> more detail in the problem report below. Perhaps the .doc file name
>> mapping should contain some additional heuristics, and fall back to
>> plain text if the file is not an Office document.
>
> (I'm going through old bug reports that have unfortunately not gotten
> any responses.)
>
> I think this makes sense.  A fix in Emacs would mean moving the .doc
> recognition from `auto-mode-alist' to...  `magic-fallback-mode-alist', I
> guess.
>
> According to the interwebs, the magic sequence for Word .doc files is:
>
> D0 CF 11 E0 A1 B1 1A E1
>
> Does anybody have an opinion here?

I wasn't aware of the practice to name plain text files *.doc; I can't
remember having encountered any file like that.  Perhaps this practice
is rare.

Would implementing this risk make opening *.doc files slower for most
users?  Perhaps that could make the trade-off not worth it.  Other
than that, I see no problem with the proposal.

Best regards,
Stefan Kangas