[Libvir] PATCH: Prevent zombie ssh tunnels

[Gerd Hoffmann]

Daniel Veillard wrote:
> On Tue, Sep 11, 2007 at 11:35:46AM +0200, Gerd Hoffmann wrote:
>> Daniel Veillard wrote:
>>>    - the ssh process dies
>>>    - libvirt based application takes some time to notice it
>>>    - the OS span a new process with the same PID after a PID rollabck
>> Can not happen as long as libvirt hasn't asked for the exist status via
>> waitpid() because the pid is still in use by the zombie ssh process.
> 
>   Hum, which is precisely why we need the patch. Still I would feel a bit
> better if we could check that priv->pid is a child of the current process
> something like (getppid(priv->pid) == getpid()) test before any kill would
> do this easilly I think.

Simply keep track which processes you've (successfully) waitpid()'ed
already, then you'll know.

cheers,
  Gerd