readme

这是一个同样来自贝尔实验室的和UNIX有着渊源的操作系统, 其简洁的设计和实现易于我们学习和理解

Redirect output of the print operator to paper. Particularly useful if
you're trying to extract information from a printer, but you don't have
access to the data the printer returns to the host.

For example,

	FontDirectory {pop ==} forall

names all the fonts registered in the FontDirectory dictionary. Simple,
but only if you can read the data returned to the host by the printer.