Converting a wstring to jstring on Linux

You have to use something like iconv(), because C++ wide strings have an opaque (read: unknown) encoding, while Java expects UTF16. Try this:

#include <iconv.h> #include <string> #include <vector> #include <iostream> std::u16string convert(std::wstring s) { iconv_t cd = iconv_open("UTF-16BE", "WCHAR_T"); if (cd == iconv_t(-1)) { std::cout << "Error while initializing iconv: " << errno << std::endl; iconv_close(cd); return std::u16string(); } std::size_t n = s.length() * 2 + 1; // Each character might use up to two CUs. const std::size_t norig = n; std::size_t m = s.length() * sizeof(std::wstring::value_type); std::vector<char16_t> obuf(n); char * outbuf = reinterpret_cast<char*>(obuf.data()); const char * inbuf = reinterpret_cast<const char*>(&s[0]); const std::size_t ir = iconv(cd, const_cast<char**>(&inbuf), &m, &outbuf, &n); if (ir == std::size_t(-1)) { std::cout << "Error while converting with iconv(): " << errno << ":" << EINVAL << ", left " << m << ", written " << std::dec << norig - n << " bytes." << std::endl; iconv_close(cd); return std::u16string(); } iconv_close(cd); return std::u16string(obuf.data(), (norig - n)/sizeof(std::u16string::value_type)); } 

If you don't have char16_t and std::u16string, you can use uint16_t as the basic character type and std::basic_string<uint16_t> or std::vector<uint16_t> as the resulting container.