lang ID for "*" (any language)

Doug Ewell doug at
Wed Jun 13 02:13:46 CEST 2012

I tend to agree with Mark that 'und' is the best choice for this.

The passage in Section 4.1 seems to start off otherwise:

"The 'und' (Undetermined) primary language subtag identifies linguistic 
content whose language is not determined.  This subtag SHOULD NOT be 
used unless a language tag is required and language information is not 
available or cannot be determined.  Omitting the language tag (where 
permitted) is preferred."

but then goes on to give reasonable use cases:

"The 'und' subtag might be useful for protocols that require a language 
tag to be provided or where a primary language subtag is required (such 
as in "und-Latn").  The 'und' subtag MAY also be useful when matching 
language tags in certain situations."

On the list we've often talked about, for example, "und-Cyrl" to 
indicate text in the Cyrillic script. In a case like this, it might not 
be that the language cannot be determined, but that it doesn't matter.

I think CLDR uses 'root' for a purpose similar to this.

Doug Ewell | Thornton, Colorado, USA | @DougEwell ­

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