3 ms·

Opening a file (or attempting to) is resource intensive and throwing/catching exceptions is sloooow.

• swolchok 17y ago
  Both opening the file and checking whether it exists involve a syscall, which dwarfs the overhead of throwing and catching an exception. If you check whether it exists and then try to open it, that's two syscalls.
  • swolchok 17y ago
    On reflection, it occurs to me that a Sufficiently Smart Compiler (TM) could figure out that you were going to open the file right after checking whether it exists and just call open(2) as the existence check instead of stat(2) and then open(2). This seems to depend on the details of the library implementation as well, though.
• Confusion 17y ago
  I don't know how many files you open in your applications, but in all of mine, the number is so small that I could not care less about the overhead of an exception.
• eru 17y ago
  The slowness of exceptions depends on your language / implementation of you language.
• gnaritas 17y ago
  > and throwing/catching exceptions is sloooow. That's not seeing the forest for the trees. Unless a specific inner loop of the program shows up in a profiler as the hotspot because of an exception, this just isn't something you should ever worry about in 99% of code. Don't throw out the nice abstractions that make code simple unless you know for sure it's the actual problem, rarely is that the case for throwing exceptions. In this particular instance, I'd say you're just wrong about not using an exception.