XmStringCreateSimple(3) on Linux
The text f5d3bea82e45, as Debian 13 (Trixie), Debian 12 (Bookworm), Debian 11 (Bullseye), Debian 10 (Buster), Debian 9 (Stretch), Debian 8 (Jessie) shipped it.
A compound string function that creates a compound string in the language environment of a widget "XmStringCreateSimple" "compound string functions" "XmStringCreateSimple"