Re: viewing attachments

[Katsumi Yamaoka <yamaoka@jpl.org>]

>>>>> In <87acqgnf7s.fsf@zip.com.au> Kevin Ryde wrote:

> Katsumi Yamaoka <yamaoka@jpl.org> writes:

>> I had many opportunities to need to see attachments containing
>> non-ASCII text or parts which have been compressed by gzip or
>> bzip2.

> Handa made a change to jka-compr in the emacs cvs (2003-01-24), adding
> decode-coding-inserted-region which I believe is meant to do emacs'
> usual charset guessing and priorities, like find-file.

I see.  The recent jka-compr uses `no-conversion' for reading
the output from the process which runs gzip, etc., and the
contents are decoded by `decode-coding-inserted-region'.  OTOH,
the earlier version uses `undecided' in order to decode the
contents while reading the output from the process.  That the
former is better is `decode-coding-inserted-region' recognizes
the coding cookies (and also `file-coding-system-alist').

> I had meant to propose a patch (for gnus-mime-copy-part actually) to
> make use of that, either by copying that code from the cvs, or just
> using it if emacs is new enough to have it.  Unfortunately I never got
> around to working out the details.

I'll look into the patch later.

>> I hit on another idea while considering about it last week.  The
>> plan is to add the charset parameter to the MIME header of an
>> attachment part automatically if there is a coding cookie in the
>> file and the MIME charset corresponding to it exists.

> If there's a cookie in the file, can't emacs just use that, without
> needing a mime charset parameter?

The principal object of that change was to enable users to add
the MIME charset manually for files which don't contain the
coding cookie.  I didn't make Emacs presume the coding system
since the auto-detection doesn't always work and Gnus should
never add the wrong charset.  Though recipients may use the
auto-decoding and it may work.

Furthermore, to add the MIME charset might be useful for
recipients who don't use Emacs, I think.

>> I've installed them (including decompressing of compressed parts)

> Maybe you can use jka-compr the same way that
> gnus-mime-jka-compr-maybe-uncompress does.

Hm, I didn't find an API of jka-compr which is suitable to that
purpose.  However, that I wasn't aware there's such a function
is the fact. ;-)  Now I want to integrate
`gnus-mime-jka-compr-maybe-uncompress' and `mm-decompress-buffer'
if it is possible.

> Or that function becomes
> gnus-mime-copy-part-jka-insert with a patch I'm proposing - see other
> message.  That would have the advantage of letting the user customize
> compression methods.

Thanks.  I will achieve them.