If C was still just a baby in 1983, what does that make Ada? Signals were a feature of Unix and C from the early 1970s; at least by 1973, if not earlier. Signa

If C was still just a baby in 1983, what does that make Ada? Signals were a feature of Unix and C from the early 1970s; at least by 1973, if not earlier. Signals were a software-based abstraction over the concept of hardware interrupts, and even today we often say that hardware interrupts are triggered by (among other reasons) an "exception" or "hardware exception". Similarly, the fact that the concept of interrupts and exceptions are related can be seen in the later (4.2 BSD, 1983) select(2) syscall, where the third fd_set argument is for capturing "exceptional condition(s)". (https://pubs.opengroup.org/onlinepubs/9699919799/functions/select.html https://pubs.opengroup.org/onlinepubs/9699919799/functions/s...) Ada enjoyed the benefit of at least another 10 years of reflection and evolution in computer science when choosing the semantics of their exception mechanism. But the success of Ada's (or Ada-like) semantics hasn't yet completely redefined the concept of exceptions.