I remember helping newbie students at USC who were very confused that even though they made the changes "PL/C USES", their program didn't work! 

> On May 19, 2024, at 5:58 PM, Rob Pike <robpike@gmail.com> wrote:
> 
> The Cornell PL/I compiler, PL/C, ran on the IBM 360 so of course used batch input. It tried automatically to keep things running after a parsing error by inserting some token - semicolon, parenthesis, whatever seemed best - and continuing to parse, in order to maximize the amount of input that could be parsed before giving up. At least, that's what I took the motivation to be. It rarely succeeded in fixing the actual problem, despite PL/I being plastered with semicolons, but it did tend to ferret out more errors per run. I found the tactic helpful.
> 
> -rob
>