Alright, after playing a while, I'm confident the following replacement function works in all cases, including the ones for which the native fputcsv function fails.
If fputcsv fails to work for you (particularly with mysql csv imports), try this function as a drop-in replacement instead.
Not sure you could do the same about the file's size, though...
Issue: working with a proxy generated against the Document NOW wsdl in a .
NET programming language, you receive an error in compilation such as: "An endpoint configuration section for contract 'Document NOWService.