This is a draft document explaining how to write locale files + for GNU libc. It will not go into details, but reference + specifications. It will on the other hand mention some of the + pitfalls, and try to document the current practice.
+ +Locale names consist of three parts. The language code, the + country/region code, and the optional modifier. The format is + language_REGION@modifier. The language code is a code from + ISO 639. The two-letter code is prefered, but a three letter + code is accepted if no two-letter code is available. The + country/region code is a code from ISO 3166. If the language + or region in question is missing in the ISO standard, one need + to get the ISO standard updated before the locale will be + included in glibc. If one can't convince the ISO 639 + maintainers that your language exists (and thus need a + language code), the glibc maintainers will refuse to add the + locale. In addition, the glibc maintainers seem to refuse + "artificial languages" like Esperanto and Lojban, even if they + got a ISO 639 code.
+ +Little is known about the requirements for the naming of + modifiers. The following modifiers are currently used: + abegede, cyrillic, euro and saaho. This might indicate that + lower case letters are prefered in modifier names.
+ +It is recommended to follow RFC 3066 when selecting locale + names.
+ +To make it easier to compare locales with each other, I + recommend using the same order for the categories in all + locales. Any order will do, so I picked the order used in most + locales, and decided to recommend this order:
+ +One should avoid cut-n-paste when possible, and instead use + the copy statement to include sections from locales + with identical content.
+ +The category entries are references to the standard used when + writing the given section. The standard refs should have + quotes around them, and should not use the <U#> + notation. They should normally look something like this:
+ ++ ++category "i18n:1997";LC_IDENTIFICATION +
Then yesexpr and noexpr entries should have the form + ^[yY<extra>] and ^[nN<extra>], + without 0 and 1 and without trailing ".*". The + reason is to make sure the expressions have the same form as + the expressions used in the C/POSIX locale (^[yY] and + ^[nN]).
+ +To test a new locale on a test machine, do the + following:
+ +Example, generating a new de_DE@euro locale using + the ISO-8859-15 charset and save it as 'de_DE':
+ ++ cp de_DE@euro /usr/share/i18n/locales/de_DE@euro + localedef -i de_DE@euro -c -f ISO-8859-15 de_DE + LANG=de_DE date ++ +
I've made a small tool check-locale + capable of detecting a few common mistakes with locales
+ +