I'm reading in, Kernighan & Plauger's 1981 edition of Software Tools in 
Pascal and in the book, the author's mention Bill Joy's Pascal and Andy 
Tanenbaum's as being rock solid. So, a few related questions:

1. What edition of UNIX were they likely to be using?
2. What versions of "Standard Pascal" were in vogue on UNIX at the time 
(1981)?
3. What combinations of UNIX/Pascal were popular?

Thanks,

Will