My compamy creates many software and some are translated. Up to here, nothing serious.
Now compiling can be a problem as older versions of msgfmt do not like the BOF character at the start of text files. It has to be clean UTF-8, but no BOF.
Anyway... Now I compiled and I need to test the results. So I need to run in French, Spanish, etc.
The normal way under Unix is to do this:
LANG=es program-name options
Although the name of the language can be a bit more complicated such as es_ES.ISO-8859-1.