UTF-8 signature is the UTF-8 character 'ef bb bf' at the start of a .cpp .c file. When you edit a UTF-8 file with notepad, it also put the signature at the start of the file.
Microsoft Visual Studio 2008 C++ compiler reads this to detect the encoding of a text file. Without this signature, a UTF-8 const string literal with chinese characters is not read correctly in Visual C++.

Please skip the  'EF BB BF' at the start of a .cpp .c file. Currently this signature causes compilation errors on GCC. Add this feature will easy the porting of WIN32 software to GCC.