pid_exists(0) lies on POSIX

[giampaolo]

From g.rodola on December 17, 2013 14:55:37

>>> import psutil
>>> 0 in psutil.get_pids()
False
>>> psutil.pid_exists(0)
True
>>> 

This is similar to issue 23 of 4 years ago.
This happens because internally we use os.kill() and according to "man 2 kill":

> If pid equals 0, then sig is sent to every process 
> in the process group of the calling process.

...which is definitively not what we want.
In case of PID 0 we should just "return 0 in get_pids()".

Original issue: http://code.google.com/p/psutil/issues/detail?id=457

[giampaolo]

From g.rodola on December 17, 2013 06:41:14

Fixed in revision 0fe8e5eb7fbe .

Status: FixedInHG
Labels: Milestone-1.3.0

[giampaolo]

From g.rodola on March 10, 2014 04:36:50

Closing out as fixed as 2.0.0 version is finally out.

Status: Fixed
Labels: -Milestone-1.3.0 Milestone-2.0.0