If you were designing a standard library of a high level language (like Rust, C++, etc.) what would it do if while getting the current time of day (e.g. SystemTime::now()
) it encountered a failed kernel system call (e.g. to clock_gettime
) and why?
What do you think the existing implementations do?
- Return error or raise exception
- Return 0
- Return undefined values (like stack garbage)
- Panic/crash/segfault
I think not being able to get the current time from the system is very exceptional. And I think exceptional circumstances should act that way and not “look like” normal executions. To me, that means letting hell break loose, and not “silently” return a 1 instead of a 0.
By similar reasoning, “Exceptions in most languages tend to be relatively expensive” is a very weak argument. We don’t expect this error-throwing code to execute a lot.
I can think if plenty of situations where system time is
In fact, if you don’t set up your containers right, the system time is almost always wrong.