Difference between revisions of "Internationalization/file format"

Revision as of 05:42, 28 April 2006

Summary

Here we evaluate various file formats used for the translation of programas. For the moment we are considering:

• XML
• po
• create an own format

PO Files

Format of PO files

A PO file has an entry for each string that has to be translated. There are two kind of them, a "normal" one and one that involves plural forms.

Normal entry

Here is the general structure of a "normal" entry:

white-space
#  translator-comments
#. automatic-comments
#: reference...
#, flag...
msgid untranslated-string
msgstr translated-string

Where the translator-comments are created and maintained exclusively by the translator, this comments have some white space immediately following the #. The other comments are created by the program that created the PO file. After the special comment "#," there can be some flags, as fuzzy shows that the msgstr string might not be a correct translation, i.e. the translator is not sure of his work. The 'untranslated-string' is the untranslated string as it appears in the original program source. The translated-string is (as the name suggests) the translated string, if there is no translation it is an empty string.

Plural form entry

white-space
#  translator-comments
#. automatic-comments
#: reference...
#, flag...
msgid untranslated-string-singular
msgid_plural untranslated-string-plural
msgstr[0] translated-string-case-0
...
msgstr[N] translated-string-case-n

Supported character encodings

character encodings that can be used are limited to those supported by both GNU libc and GNU libiconv. These are: ASCII, ISO-8859-1, ISO-8859-2, ISO-8859-3, ISO-8859-4, ISO-8859-5, ISO-8859-6, ISO-8859-7, ISO-8859-8, ISO-8859-9, ISO-8859-13, ISO-8859-15, KOI8-R, KOI8-U, CP850, CP866, CP874, CP932, CP949, CP950, CP1250, CP1251, CP1252, CP1253, CP1254, CP1255, CP1256, CP1257, GB2312, EUC-JP, EUC-KR, EUC-TW, BIG5, BIG5-HKSCS, GBK, GB18030, SHIFT_JIS, JOHAB, TIS-620, VISCII, UTF-8.

I thing they are a lot...

Positive aspects

• Powerful plural handling
• Format created for translation purpose
• Easy for humans to read
• Used by gettext, kbabel, rosetta and many other programs

Negative aspects

XML

Positive aspects

Negative aspects

• Not every body knows it
• Microsoft seeks XML-related patents, that could restrict the use of XML (there should be a "Very negative aspect" section)

New Format

Positive aspects

• Free to do what we want

Negative aspects

• A new format? Why should we be different?

Conclusions

References

• Gettext manual (for PO files)
• Microsoft and XML