XmObjectAtPoint(3) on Linux
The text 112764f1464a, as Debian 13 (Trixie), Debian 12 (Bookworm), Debian 11 (Bullseye), Debian 10 (Buster), Debian 9 (Stretch), Debian 8 (Jessie) shipped it.
A toolkit function that determines which child intersects or comes closest to a specified point "XmObjectAtPoint"