Difficulty/Confusion with Sockets

[us...@domain.invalid]

Thanks in advance for any pointers.

I am writing an addon that must be installed in both Firefox and T-Bird.
The two instances of this addon will communicate via sockets for IPC.
The server socket is in the FF portion of the addon.

So here is my issue... If FF is not running and I start T-Bird, my addon
in T-Bird tries to connect to the server socket in FF. The socket
transport is created ok and my addon opens its output stream ok. It even
writes a byte of data ok.

But the server is not running at all so it would seem that the
connection cannot really have been created. However, I cannot seem to
determine that this is the case. I am not looking for a response from
the server socket, I am simply broadcasting some data that I want the
addon in FF to pickup if it is there. If it is not, no big deal. But I
do want to detect if the listener is not there (or goes away after
having been there).

How can I do this?