MythMessage is a simple messaging protocol, added in 0.25 to replace the old mythtvosd protocol. The primary difference is that MythMessage is fully integrated with the new UI, meaning messages will also pop up in the menu, rather than only during playback.
MythMessage listens on UDP port 6948, and currently accepts a single simple XML format.
<mythmessage version="1"> <text>Your Message Text</text> <timeout>int</timeout> </mythmessage>
Timeout accepts an integer value in seconds before the popup is automatically closed. If timeout is not given, the popup will not clear until manually selected on the frontend. Messages only timeout while playing back media; if a menu is present then the message box will wait for OK to be clicked before clearing.
To send the message to a single address, use bcastaddr parameter with that single IP.
Example: mythutil --message --message_text $message --timeout 5 --bcastaddr 192.168.1.255
See also MythNotification; to use the new Notification Center introduced in 0.27