xdm(1) on Linux
The text 8b13aab7d461, as Debian 4.0 (Etch) shipped it.
X Display Manager with support for XDMCP, host chooser
Flags it lists
-
-config -
-debug -
-error -
-nodaemon -
-resources -
-server -
-session -
-udpPort -
-xrm