[vlc-devel] ISO 639-3

[Bruno Haible]

[Dropped CC to vlc-devel mailing list.]
John Cowan wrote:
> Bruno Haible scripsit:
> > ISO 639-3 abbreviations can change over time
> 
> In fact not, according to the usual understanding of "change".  In no
> case does a code refer to something and then cease to refer to it, or
> begin to refer to something else.  Here's the Registration Authority's
> policy statement from http://www.sil.org/ISO639-3/changes.asp (I've put
> RFC 2119 keywords in CAPS here):
> ...
> they all share the same set of abbreviations and the same change-control
> policies. 

Well, that's theory. In reality [1], in ISO 639-3, in one year, they have
merged 8 language identifiers and split 9 language identifiers.

Whereas in ISO 639-2, the official rules are equally weak [2], but much
less changes are made in practice [3]:
  - In 2008, Croatian and Serbian have received new 3-letter codes, but this
    is irrelevant for Unix since they already had 2-letter codes and these were
    not changed.
  - In 2001, Javanese has received a new 2-letter code and a new 3-letter code.
  - Deprecated identifiers (mo, jw, sh, in, ji) will not be reused.

In summary, it is fine to use identifiers from ISO 639-1 and ISO 639-2 for
translation catalog names. But when you use ISO 639-3 identifiers, you should
be prepared to surprises.

Bruno

[1] http://www.sil.org/iso639-3/
[2] http://www.loc.gov/standards/iso639-2/faq.html#19
[3] http://www.loc.gov/standards/iso639-2/php/code_changes.php