XmDataFieldSetSelection(3) on Linux
The text a1a77bfd7d2e, as Debian 13 (Trixie), Debian 12 (Bookworm), Debian 11 (Bullseye), Debian 10 (Buster), Debian 9 (Stretch), Debian 8 (Jessie) shipped it.
A DataField function that sets the primary selection of the text "XmDataFieldSetSelection" "DataField functions" "XmDataFieldSetSelection"