今天读到 Eric S. Raymond 《The Art of UNIX Programming》的最后一章 "Futures: Dangers and Opportunities"。才了解到， utf-8 居然是专门为 Plan 9 而设计的。下面是书中的引文：
Some Plan 9 ideas have been absorbed into modern Unixes, particularly the more innovative open-source versions. FreeBSD has a /proc
file system modeled exactly on that of Plan 9 that can be used to query or control running processes. FreeBSD's rfork
(2) and Linux's clone
(2) system calls are modeled on Plan 9's rfork
(2). Linux's /proc
file system, in addition to presenting process information, holds a variety of synthesized Plan 9-like device files used to query and control kernel internals using predominantly textual interfaces. Experimental 2003 versions of Linux are implementing per-process mount points, a long step toward Plan 9's private namespaces. The various open-source Unixes are all moving toward systemwide support for UTF-8, an encoding actually invented for Plan 9.
Plan 9 到现在，大约10年过去了。Unix 们也正不断地向 Plan 9 规划出的世界前行，构建更加美丽的 UNIX World。