On Wed, Dec 7, 2011 at 10:27, Felipe Almeida Lessa wrote:

On Wed, Dec 7, 2011 at 1:19 PM, Brandon Allbery wrote:

...

They *do* terminate; a zombie is a dead process waiting for its parent to reap it with waitForProcess. There's also some POSIX stuff you can do to have them auto-reaped, but doing that correctly and portably is somewhat painful.

But zombie processes do consume a row in the process table, right? If so, then it's bad to have them around.

Yes, and they count against the per-uid process limit. -- brandon s allbery allbery.b@gmail.com wandering unix systems administrator (available) (412) 475-9364 vm/sms

Thank you very much for your answers. Felipe's suggestion to use waitForProcess after terminateProcess did the trick. No more zombies around :) Best regards, Dan Rosén On Wed, Dec 7, 2011 at 4:39 PM, Donn Cave wrote:

Quoth Felipe Almeida Lessa ,

...

On Wed, Dec 7, 2011 at 1:19 PM, Brandon Allbery wrote:

...

They *do* terminate; a zombie is a dead process waiting for its parent to reap it with waitForProcess. There's also some POSIX stuff you can do to have them auto-reaped, but doing that correctly and portably is somewhat painful.

But zombie processes do consume a row in the process table, right? If so, then it's bad to have them around.

Correct. As noted above, clean up with waitForProcess to release this resource. If it's more convenient, that could be done up front, by forking twice and waiting for the intermediate process. One possibly convenient way to do that might be something like runCommand "eprover &".

Donn

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On Wed, Dec 7, 2011 at 20:35, Jason Dagit wrote:

...

They *do* terminate; a zombie is a dead process waiting for its parent to reap it with waitForProcess. There's also some POSIX stuff you can do to have them auto-reaped, but doing that correctly and portably is somewhat painful.

You can use a double fork to make this portable and not painful. It's just that you have to fork twice, which can be expensive in some cases.

And problematic if you're using a pipe to communicate with the child, which seemed quite possible. -- brandon s allbery allbery.b@gmail.com wandering unix systems administrator (available) (412) 475-9364 vm/sms