XmCreateDialogShell(3) on Linux
The text 5fd8cb2569d7, as Debian 13 (Trixie), Debian 12 (Bookworm), Debian 11 (Bullseye), Debian 10 (Buster), Debian 9 (Stretch), Debian 8 (Jessie) shipped it.
The DialogShell widget creation function "XmCreateDialogShell" "creation functions" "XmCreateDialogShell"