Compaq Tru64 UNIX Operating System supports two types of Unicode-based locales -- UTF-8 locales, which use forms of Unicode for both the multibyte and wide character encoding, and "@ucs4 locales", which use Unicode for the wide character encoding only. The @ucs4 locales have been in use for over five years. The UTF-8 locales were first introduced to provide support for the euro in Europe, but Tru64 UNIX now extends the support to Asian locales including Chinese, Japanese, and Korean.

This paper is intended to give an overview of the implementation of Unicode support in Compaq Tru64 UNIX. In addition, the following topics will also be discussed:

• Efficient localization technique for supporting Unicode locales.
• Migration of existing non-Unicode based locales to Unicode locales.
• Using Unicode to support the new Chinese GB18030-2000 character set.

After reading through this paper, the readers should have a basic understanding of what kind of Unicode support is provided by the Tru64 UNIX operating system and how it is being implemented. This paper also illustrates how to make use of the Unicode support provided in the operating system to help application developers write Unicode based applications.