How do I reverse engineer Mac OS X language localisation files for natural language learning?

Question

OK, the goal of this question is not strictly programming related but it is a question programmers can answer using programming tools, and programmers may find useful answers here. Bear with me.

I find changing the system language in Mac OS X a useful way to augment my learning of natural languages, eg French. However sometimes I find a menu item or dialog box in French that I can't understand and it's a bore to google the translation or change the system language back to English. But I know that the English translation is hidden away somewhere in the localisation file and maps somehow to the French phrase. So what I want to do is extract all the text from all the localisation files to develop a mapping of this phrase in English = that phrase in French so I can look it up easily.

I know that the localisation files are stored in something like Localizable.strings, lproj files and nib files but I can't make head or tail of how they are stored or how to work with them. I can program but I've never written anything in Xcode. All the information I can find is for Mac OS / iOS programmers to localise their software, not for hackers to extract already made localisation information.

How can I extract the foreign language information as plain text from Mac OS X system and 3rd party software localisation files? Thanks!

Answer 1

Strings files are easy. They're simply dictionaries serialized as property lists. The dictionary keys are used by the program to look up the given string for a particular localization. You can build a mapping from English to another language by loading both dictionaries, iterating over the keys, and using the value from the English dictionary as the key in your output and the value from the other language dictionary as the value in your output.

NIBs are harder. The build process "compiles" NIB files in to a form that's not conduicive to editing or parsing. If you have access to uncompiled NIB files then you can use ibtool --export-strings-file to dump a strings file, which you could then process as per above. If you don't then I think you may have a hard time.