2011년 10월 23일 Do Not Fall Back to UTF-8 Everyone knows that
UTF-8 is now universal; it is so universal that a half of all
webpages collected by Google is in UTF-8 by 2010. This success
is certainly backed by an ASCII-compatibility (and thus, an
ability to encode many Latin letters without further overheads)
of UTF-8, which UTF-16 certainly does not have. But it does not
mean that you can use UTF-8 for everything. Case study: You are
writing an IRC client. IRC (Internet Relay Chat) is very ancient
chatting protocol and still kicking around. While IRC is not
designed for Unicode in mind1, it is a text-based format and all
UTF-8 multibyte characters do not overlap with ASCII characters
like ! which are special in IRC. As a result nowadays UTF-8 in
IRC is quite common, and even if the default encoding is not
UTF-8 it seemed that using UTF-8 for every characters not in
that default encoding is reasonable. Right? No. You are dead
wrong. It may make sense when you are limited to Western
charsets like ISO 8859-1. For