XmInstallImage(3) on Linux
The text 6f69aac6b06c, 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 adds an image to the image cache "XmInstallImage" "pixmaps"