[fpc-pascal] D-Bus. Non blocking listening for signals

[Henry Vermaak]

On 13 January 2011 19:51,  <dibo20 at wp.pl> wrote:
>
> I'm trying with "dbus_connection_set_watch_functions" but this is not easy
> like it look. I thought that I must only register my event procedures by
> calling this functions but there is much more work. I have a headache. Now I
> understand why dbus documentation begins with the words "If you use this
> low-level API directly, you're signing up for some pain" ;) . Tomorrow I
> look for some "live example" of using this functions in C.

Indeed, it's pretty ugly.

> I tried with thread. It doesn't catch all signals even if I call sleep(1) in
> loop. I don't know what is reason of this loss. Thread and AddEventHandler
> have this same problem - they don't catch all signals. Only one way which
> works is "g_main_context_set_poll_func" but now I see that the application
> consumes 30% CPU. So now I understand why it catch all signals. @Matthias
> how you solved problem with CPU and this function?

I changed your code to run in a thread and it works well for me.  I
made a thread safe TQueue derivative that I add messages to, then I
notify the gui thread with PostMessage.  The gui thread pops the
messages from the queue and displays them.  This works even if I add
huge delays in the gui thread, since the queue is a buffer.  This
solution should also work with other widgetsets.

I'll send you some code tomorrow (it's on my work computer).

Henry