Yeah it was, you seem to be mistaken: http://doc.cat-v.org/plan_9/4th_edition/papers/comp http://doc.cat-v.org/plan_9/4th_edition/papers/comp To make it easie

Yeah it was, you seem to be mistaken: http://doc.cat-v.org/plan_9/4th_edition/papers/comp http://doc.cat-v.org/plan_9/4th_edition/papers/comp To make it easier to share code with other systems, Plan 9 has a version of the compiler, pcc, that provides the standard ANSI C preprocessor, headers, and libraries with POSIX extensions. Pcc is recommended only when broad external portability is mandated. It compiles slower, produces slower code (it takes extra work to simulate POSIX on Plan 9), eliminates those parts of the Plan 9 interface not related to POSIX, and illustrates the clumsiness of an environment designed by committee. Pcc is described in more detail in APE—The ANSI/POSIX Environment, by Howard Trickey. I'm obviously aware that it wasn't the main compiler/compiler suite for Plan 9 (of which I've submitted links to papers about quite a few times), but it was there.