Error while restarting using SIGHUP

[ivirabyan]

There was an error, saying "Pidfile is already exists" while restarting
using SIGHUP. The problem arises only when "--pidfile" option is used.

Related to: https://github.com/ask/celery/issues/26

[ask]

Thank you!

This may have been fixed (or partly fixed) by f4fe925 which was released as part of version 2.5.2.

Please review and report :)

[ivirabyan]

Thanks for the answer. I've tried 2.5.2, the problem still arises. As I understand ask@f4fe925 is about corrupted pidfiles.
My problem is that pidfile does not get removed when the process is restarted. This is because pidfile is relased on interpreter exit, which is not the case.

Also, I have rewritten my patch, making PIDFile class unchanged. I moved creation/deletion of a pidfile into the WorkController class.

[ask]

Aha, so I guess the process id is still alive, so that the stale pidfile detection doesn't work,
thanks I'll merge!

[ask]

I have to move it to the end of the stop() method though, because not it could create a race
if the process has not been properly shutdown (imagine a blocking shutdown process and an automatic restarter)

[ivirabyan]

The process id is still alive because it is the same process :)

[TylerSheffels]

I think