Subject: Re: Unicode support in iso9660.
To: None <tech-kern@netbsd.org>
From: Valeriy E. Ushakov <uwe@ptc.spbu.ru>
List: tech-kern
Date: 11/18/2004 13:27:12
On Thu, Nov 18, 2004 at 12:57:21 +0900, MINOURA Makoto wrote:

> What we have to consider:
[...]

All these topics are important, but orthogonal to my proposal.


> Partly discussed in http://www.haun.org/ml/b-l-j/a/500/572.html
> (in Japanese, sorry).

Requires authentication.


> Anyway, I do not think all of the above can be solved in a
> single solution:), but it is worth discuss before adding a
> mount option to specify encoding.

Not encoding - transcoding!  It's a cheap and effective way to dodge
all the conceptual encoding problems that you mentioned.  I.e. instead
of making a "declarative" statement "This filesystem has filenames in
encoding FOO", we make a "procedural" request "Please apply this
mangling procedure (transcoding) to the filenames in this filesystem".
Thus we remain within the scope of the existing "file name is just a
stream of bytes" paradigm, and it's up to user to ensure the mangling
does the right thing.

Yes, this is not "generic enough" to support on a single system users
that use different locales.  OTOH, they already have enough rope to
shoot themselves in the foot - a single FFS filesystem, happily
unaware of all things related to encodings, allow users that use
different locales to create file names e.g. in Russian and Latvian.

There's existing practice (FreeBSD) and it worked out really well
there.  I don't see why we can't adopt it.

Thanks.

SY, Uwe
-- 
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