If I want to use C++11\'s regular expressions with unicode strings, will they work with char* as UTF-8 or do I have to convert them to a wchar_t* string?
C++11 regular expressions will "work with" UTF-8 just fine, for a minimal definition of "work". If you want "complete" Unicode regular expression support for UTF-8 strings, you will be better off with a library that supports that directly such as http://www.pcre.org/ .