IPython.core.kitty:_ancestor_process_names

Extended Summary

On Linux this reads /proc directly: importing psutil costs upwards of 10ms, which is a real slice of IPython's startup, and this runs on every interactive start. /proc/<pid>/stat holds both the name psutil would report and the parent pid, so one read per ancestor is enough.

Everywhere else -- macOS, or a Linux without /proc -- fall back to psutil, which IPython depends on anyway.