Boost C++ Libraries: Ticket #9968: [filesystem] Streams don't handle unicode file name on Windows

anonymous — Sun, 08 Mar 2015 16:53:22 GMT

Same problem here, I tried also utf8 and it doesn't work as well:

#include <boost/filesystem/detail/utf8_codecvt_facet.hpp>
(...)
std::locale global_loc = std::locale();
std::locale loc(global_loc, new boost::filesystem::detail::utf8_codecvt_facet);
boost::filesystem::path::imbue(loc);
(...)
boost::filesystem::ofstream hello("שלום.txt");

it creates ﾗｩﾗ慵勉・txt since I'm on SJIS encoding.

Windows machine, i686-w64-mingw32-g++ (GCC) 4.8.3 on Cygwin

anonymous — Sun, 08 Mar 2015 16:55:01 GMT

Same problem here, I tried also utf8 and it doesn't work as well:

#include <boost/filesystem/detail/utf8_codecvt_facet.hpp>
(...)
std::locale global_loc = std::locale();
std::locale loc(global_loc, new boost::filesystem::detail::utf8_codecvt_facet);
boost::filesystem::path::imbue(loc);
(...)
boost::filesystem::ofstream hello("שלום.txt");

it creates ﾗｩﾗ慵勉・txt since I'm on SJIS encoding.

Windows machine, i686-w64-mingw32-g++ (GCC) 4.8.3 on Cygwin

Artyom Beilis — Wed, 07 Oct 2015 15:16:56 GMT

The problem is that boost::filesystem::ofstream uses native filebuf - and mingw does not support wide path parameter so basically it fails back to narrow strings.

In these terms ofstream is not really useful under mingw.

anonymous — Mon, 22 May 2017 14:43:04 GMT

Still an issue in 1.63.

Workaround: Create a temporary file with a normal name (file.tmp) and use

boost::filesystem::copy_file("file.tmp", destfile)

That is a major nuisance, though.

boost.flamefire@… — Mon, 25 Sep 2017 02:28:15 GMT

Came across the same problem. I was wondering: If boost has to fall back to narrow character set on mingw then why doesn't it convert the filename correctly?

In my case I have to write to the user directory but the username contains an umlaut. Internally I use all UTF8 in the string (std::string) and also have the path as an UTF8 string. When I pass it to e.g. memory mapped files or the directory functions it works. In MSVC it also works (widechar open function for fstream) but on MinGW it falls back to narrow char open and (maybe?) passes the utf8 string raw into the open function instead of converting it to the system encoding.