Bug 1682 - Handles leak with Process.Start if Process.WaitForExit is not called
Summary: Handles leak with Process.Start if Process.WaitForExit is not called
Alias: None
Product: Runtime
Classification: Mono
Component: io-layer ()
Version: unspecified
Hardware: PC Linux
: --- normal
Target Milestone: ---
Assignee: Bugzilla
: 6437 ()
Depends on:
Reported: 2011-10-25 14:39 UTC by Randy Chapman
Modified: 2013-01-11 16:23 UTC (History)
3 users (show)

Is this bug a regression?: ---
Last known good build:

Repro case (809 bytes, text/plain)
2011-10-25 14:39 UTC, Randy Chapman

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Description Randy Chapman 2011-10-25 14:39:36 UTC
Created attachment 764 [details]
Repro case

According to MSDN documentation, and running on win7 with MS CLR, it is valid to start a process with p = Process.Start() and then call p.Close(), without ever calling p.WaitForExit().  You can, in fact, save the process id from the original process object, and create a new one with Process.GetFromProcessId, and call WaitForExit() on that new object, and there will be no leak on the MS CLR.

However, if you do this with the Mono CLR, you can only start 255 processes before failure:

    Starting process #255
    CreateProcess: error creating process handle

I checked this on Linux Mono 2.10.5 and OS/X 2.10.6

Simple repro code is attached.
Comment 1 Zoltan Varga 2011-11-04 13:16:10 UTC
Fixed in HEAD/mono-2-10 branch.
Comment 2 Rodrigo Kumpera 2013-01-11 16:23:12 UTC
*** Bug 6437 has been marked as a duplicate of this bug. ***