Kernighan had the experience then of writing "Software Tools in Pascal", updated from "... in RATFOR". RATFOR was a pre-processor for FORTRAN that made it look

Kernighan had the experience then of writing "Software Tools in Pascal", updated from "... in RATFOR". RATFOR was a pre-processor for FORTRAN that made it look sort of Pascal-ish. People could use it to code and run unixy utilities on their machines that only had a FORTRAN compiler. Good times! Getting those translated to Pascal was a big enough nuisance to motivate the essay.