postgres/src/backend/utils/mb

src/backend/utils/mb/README

Encodings
=========

conv.c:		static functions and a public table for code conversion
mbutils.c:	public functions for the backend only.
stringinfo_mb.c: public backend-only multibyte-aware stringinfo functions
wstrcmp.c:	strcmp for mb
wstrncmp.c:	strncmp for mb

See also in src/common/:

encnames.c:	public functions for encoding names
wchar.c:	mostly static functions and a public table for mb string and
		multibyte conversion

Introduction
------------
	http://www.cprogramming.com/tutorial/unicode.html