Documentation was almost nonexistent ( I had very worn copies of the two [ Leffler et al.] documents from the4.3BSD manual set) so when you needed an answer, you looked it up in the source code. 当时几乎没有文档可查(我从一堆4.3BSD手册中找到两本Leffler等人编写的文档,但非常破旧),因而在想解决某个问题时,就得查源代码。