gnome-calls(1) on Linux
The text e76ba677ffe2, as Debian 11 (Bullseye) shipped it.
A GTK+ user interface for PSTN phone calls
Flags it lists
-
--daemon -
--dial -
--display -
--help -
--help-all -
--help-gapplication -
--help-gtk -
--provider -
-d -
-h -
-l -
-p