Text files are nowadays usually encoded in Unicode, and may consist of
very different scripts - from Latin letters to Chinese Hanzi -, with
many kinds of special characters - accents, right-to-left writing marks,
hyphens, Roman numbers, and much more. But the POSIX platform APIs for
text do not contain adequate functions for dealing with particular
properties of many Unicode characters. In fact, the POSIX APIs for text
have several assumptions at their base which don't hold for Unicode
text.

This library provides functions for manipulating Unicode strings and for
manipulating C strings according to the Unicode standard.
