1

I am looking for a reliable cross-platform way to check if a process with a specific pid is running. Two possible solutions came up:

  1. kill -0 $PID — exit status is 0 if it the process exists and 1 if not, however it also returns 1 for pids that require additional privileges to kill.
  2. ps a | grep "^\s*${PID}" and similar which are plain ugly.

Is there a way to have something like #1, but without the owner limitation?

  • Note that knowing that a process isn't running isn't very useful, because by the time you do something with the result the process may be dead, and may even be a different just-started process after the prior process with the same PID died. The only time you can rely on a PID being meaningful is from its parent, until the next time you call one of the wait* functions. – Gilles 'SO- stop being evil' Feb 15 '12 at 6:23
4

Can you write a small C program? The kill(2) system call does return -1 if your UID doesn't have permission to send a signal to a given process, but errno is set to EPERM in that case, as opposed to ESRCH for a non-existent PID. I'm reasonably certain you could make it portable across Solaris, HP-UX, Linux and the *BSDs. You would have to compile it for each platform.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.