Re: [Lcd4linux-devel] How get i the verbose output? / Hash-Age problem

[Michael R. <re...@eu...>]

Hi Markus,

> When the Timer hits the 10000sec he begins the reread everytime the  
> value is called.

Fixed. Thanks for debugging this one! I reset the age of a specific 
element, but not the hash itself. Should work now.


> PS: My next Plugin is waiting in my development-directory. It will be  
> able to read RDF-Newstickers from the web. but we should first fix the  
> Xmms/hash-problem.

Sounds very interesting!

BUT! There's a big BUT!
We had some very big problems with the old mail client, which checks 
POP3 mailboxes and displayed the number of new/unread mails. The problem 
was that it took some time to parse the mailbox over an internet 
connection, there have been delays up to several seconds. This is very 
bad for the lcd4linux internal timing mechanisms. The display got 
"stuck" in this moments, which looked quite ugly.

That's why I don't want to port the mail plugin to the "next 
Generation", because I'd have to solve this issue.

The only solutzion that comes to my mind is an "asynchronous parsing": 
The plugin should do a fork() upon initialization, and the forked extra 
thread should parse the mailbox (or the ticker in your case), and 
deliver the results over a shared memory buffer. The "real" plugin just 
reads this memory buffer. There have to be some synchronisation 
mechanisms with mutexes and stuff...

Take a look at the (old) X11 driver, it already is asynchronous, you 
will find all the forking and shared memory stuff in there.

Anyone with better ideas?


bye, Michael

-- 
Michael Reinelt                                   Tel: +43 676 3079941
Geisslergasse 4                                   Fax: +43 316  692343
A-8045 Graz, Austria                          e-mail: re...@eu...