Discuss whether system_executor should provide a way to wait for outstanding tasks

[chriskohlhoff]

[chriskohlhoff]

Pre-Lenexa Summary

[async.system.exec]

Currently the system_executor specification says:

If the program is terminated by any means, and there remain unexecuted functions objects that have been submitted using post or defer, these function objects are discarded without calling them.

The question is whether the system_executor should provide some mechanism for waiting for the completion of all outstanding tasks, and if so what form this should take? For example, a static member function system_executor::join_all().