bug#13086: 24.2.50; Emacs seems to hang at w32proc.c:1126

[Paul Eggert]

On 12/06/12 12:25, Eli Zaretskii wrote:
 
> How can that happen, if PID is not our child process?

Because Emacs regularly kills processes that it thinks are its
children.  If I'm running several applications, one of them
can kill the other even if the applications are otherwise
unrelated -- that's standard Unix semantics.  So if
Emacs mistakenly thinks that it has a child with PID 1234
and does the equivalent of "kill -9 1234", which is something
that delete-process does, Emacs can kill an innocent and
unrelated victim.

> the hypothetical problem you envision
> hardly justify losing an Emacs session.

It depends on how important the other process is to the user.
Sometimes, the other process is more important than Emacs,
and the user would rather lose this Emacs session than lose
the other process.

>> One possibility is for Emacs to fall back into recovery mode
> 
> It is much easier to remove the offending process object from the list
> of those we expect to be dead.

Sure, but there's a good case for being cautious here, even if
it's a bit harder to be cautious.