Error handlers, what is called callbacks in the article, have existed since time immaterial in operating systems. They have also been popular in PL/I and Lisp a

Error handlers, what is called callbacks in the article, have existed since time immaterial in operating systems. They have also been popular in PL/I and Lisp as signals and conditions. Unfortunately, Unix implementation kinda limited them (there is limited number of system signals, error handlers do not stack), so they never became really popular in C.