XmGetPixmapByDepth(3) on Linux
The text d4e557faa833, as Debian 13 (Trixie), Debian 12 (Bookworm), Debian 11 (Bullseye), Debian 10 (Buster), Debian 9 (Stretch), Debian 8 (Jessie) shipped it.
A pixmap caching function that generates a pixmap, stores it in a pixmap cache, and returns the pixmap "XmGetPixmapByDepth" "pixmaps"