With #275 @tonemackay ran into an issue where the caller expects a path to the BOINC data dir as an std::string. I haven't checked where that path ends up but I have seen old C fopen code so it's a bit tricky to know what the C or C++ libraries expect in terms of string encodings for paths. It's probably better to stick to unicode or utf8 and use boost for everything.

boost::filesystem and Qt both support this, I believe, so we just have to change our own code.