MythWelcome binds to port 6948, MythFrontend unable to use MythMessage

[Michael Haas <haas@…>]

MythWelcome? binds to port 6948, thus making it impossible for MythFrontend to bind to that port. This means thatmythuitl --message is unable to send a message to the frontend.

Steps to reproduce:

1. Start MythWelcome?
2. Start MythFrontend from MythWelcome?
3. Run {{{mythutil --message --message_text "Hello World" --timeout 60

Expected result: Seeing "Hello World" on my TV.

Actual result: Output on TV is the same as before, no popup.

Note: Messaging works as expected if MythWelcome? is not running.

Attached:

• mythwelcome log file (where we can see it binds to the port)
• mythfrontend log file (where we can see the port is in use)
• mythfrontend --version

[wagnerrp]

I actually thought there was another open ticket for this, but I can't find one. I have discussed this with Stuart Morgen in the past few weeks. There's a couple options here. With Stuart's "idle mode" frontend, there is little reason why MythWelcome? wouldn't dissolve into MythFrontend, and MythShutdown? into MythBackend?, making the problem just go away. I could add a hook into the MythSystem? class, allowing the listen server to be taken down when the UI stop listening for other input events. I could add checks in the ServerPool? class for broadcast and multicast addresses, to allow reuse. The second and third ones should likely be done anyway, even if the first happens.

[Raymond Wagner <rwagner@…>]

In 8532584f4c3d0f7d14b88eed6c492073fbed8f86/mythtv:

Fix UI message interface availability when using MythWelcome?.

This adds a mechanism to disable the UI message interface when running
MythFrontend, freeing up the necessary ports to allow the frontend to
listen on them and receive events while MythWelcome? idles in the
background. The interface is brought back up on MythWelcome? when the
frontend terminates.

This commit contains an ABI bump for two new events and a MythSystem?
constant.

Fixes #10815