Re: [bug-gnu-libiconv] Missing support for ISO-6937

[Marian Ďurkovič]

Hi Bruno,

On Mon, Sep 14, 2009 at 10:05:18PM +0200, Bruno Haible wrote:
> In [1] you point to a document [2] whose appendix A contains the specification
> to be implemented. Most encodings needed therein are not related to ISO 6937.
> The only reference is in figure A1: "This table is a superset of ISO/IEC 6937
> with addition of the Euro symbol." So it's not exactly ISO 6937.

The euro symbol is the only difference, so it's not a big problem even if
standard ISO6937 is being used. In fact, adding it to conversion table
does not break anything, since position 0xA4 is empty and AFAIK there are
discussions to add euro symbol also to the official ISO6937 spec.

> I think such a specialized encoding, defined by a Digital Video standard,
> should be implemented in digital video decoding software, not in general
> purpose libraries such as glibc or libiconv. See also libiconv/NOTES for
> the scope of libiconv.

ISO6937 is used not only in DVB, but also for X.400, X.500 and other
telecommunication services. It's usability is thus more general
and glibc supports it for a long time.

> The implementation is not hard, by the way: The essential ingredient is a
>   (diacritic, letter) -> combined diacritic
> mapping table.

Yes, I already implemented a replacement for VLC:

http://git.videolan.org/?p=vlc.git;a=commitdiff;h=475b627e585a1f3132378733e4dfc0076326f6bf

Anyway, the feeling on vlc-devel mailinglist was, that implementing
conversion routines in VLC is suboptimal and I do believe that having
ISO6937 support in libiconv would help several other applications besides
VLC itself (and also remove the difference between glibc and libiconv
in this).

Thus, I'd like to kindly ask you to reconsider one more time, if it's
really not feasible to implement ISO6937 support into libiconv.


   Thanks & kind regards,

      M.