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From: Ken Brown <kbrown@cornell.edu>
To: cygwin@cygwin.com
Subject: Re: posix_spawnp creates ghost processes
Date: Fri, 24 Apr 2020 08:47:42 -0400	[thread overview]
Message-ID: <41635049-2112-0d95-4adf-3e14f6f96029@cornell.edu> (raw)
In-Reply-To: <008201d61a0a$328a5510$979eff30$@gmail.com>

On 4/24/2020 3:30 AM, Kristian Ivarsson via Cygwin wrote:
> Hi all
> 
> We're having a rather complex application and have noticed a rather weird
> behaviour that I cannot find any information about
> 
> We're using posix_spawnp and sometimes it creates extra "ghost-process(es)"
> non visible to cygwin (via e.g. process status (ps)) but visible to Windows
> (Task Manager)
> 
> The function doesn't fail and it doesn't report any error, but sometimes
> (hard to reproduce deterministically) it creates one, or more, extra
> processes of the same binary
> 
> 
> 
> Have anyone noticed and/or have some information/ideas about this ?

Cygwin's posix_spawn uses execve under the hood.  The latter creates a new 
Windows process, does some housekeeping, and then transfers control from the old 
process to the new one.  There will be a short period of time when both 
processes exist from the Windows point of view.

Ken

      parent reply	other threads:[~2020-04-24 12:47 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-04-24  7:30 sten.kristian.ivarsson
2020-04-24  8:10 ` Andrey Repin
2020-04-24 13:18   ` Sv: " sten.kristian.ivarsson
2020-04-24 12:47 ` Ken Brown [this message]

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