tcpser(1) on Linux
The text d9361d71680d, as Debian 4.0 (Etch) shipped it.
emulate a Hayes compatible modem
Flags it lists
-
-A -
-B -
-C -
-D -
-I -
-L -
-N -
-S -
-T -
-a -
-c -
-d -
-h -
-i -
-l -
-n -
-p -
-s -
-t