You make an overall valid point that despite reading the documentation, the resulting behavior of your code was not what you expected -- I take that specific complaint very seriously anytime anyone makes it.


Regarding your recommendations:

I) Unfortunately this is not a trivial topic; it has been discussed extensively elsewhere.  As you point out, this is a different topic.

II) Please do note the atexit documentation does not suggest it is a tool for triggering actions when a _process_ exits.  I don't think I'm a pedant but that kinda makes me sound like one.



Here are some suggestions on potential next steps:

1. If the documentation for atexit is inadequate in getting across its true nature and limitations, would you please open a new issue against atexit's documentation?  In it, please recommend what would have made it much clearer.

2. Detecting that atexit functionality has been invoked inside a process created using multiprocessing does not cover the full range of possibilities where atexit functionality is impacted and thus the originally-intended/desired behavior will not occur.  Ignoring the larger set of possible scenarios for the moment, I think a case could be made to add an atexit-like feature to multiprocessing that would give you specific control over what happens when a process created by multiprocessing is done and terminates.  If that appeals to you too, would you consider opening a new issue proposing this feature request and, given your use cases to date, please suggest things that would make it especially valuable?



Apologies if any choice of phrasing on my part added in any way to your frustration -- it was not my intention.  I do hope you'll be able to contribute something more, possibly along the lines I suggest.