Could somebody be so kind and tell a newbie how to convert a string of single byte characters (char) to a string of Unicode characters (wchar) in a way that the characters with more than 7 bits (e. g. German Umlaute, French accents) are treated correctly?
I use "iconv" library for this purpose. It allows you to make arbitrary conversions from different source and destinantion encodings. http://www.gnu.org/software/libiconv/ It is licensed as LGPL, so you can also use it in commercial products. This library is standard on Linux, used by many programs. So if your platform is Linux, you can expect it to be already installed.