Re: [ddccontrol-devel] Panel Applet, libddcci

[Nicolas B. <ni...@bo...>]

Hello Christian,

On Fri, 2005-09-02 at 14:40 +0200, Christian Schilling wrote:
> Am Freitag, den 02.09.2005, 11:37 +0200 schrieb Nicolas Boichat:
> > Hello Christian,
> > 
> > On Fri, 2005-08-26 at 12:20 +0200, Christian Schilling wrote:
> > > > > i'm currently working on a panel applet for gnome, with allows quick
> > > > > changeing of profiles created with gddccontrol.
> > > > 
> > > > Nice idea .-) One thing you should take care of is multi-screen (which
> > > > monitor are you controlling?).
> > > yes i am aware of this, the applet is now working with one monitor only
> > > (first one thats found), but i intend to make an config dialog to chose
> > > the monitor.
> > > > 
> > > > > while doing this i noticed libddcci is build as a static library.
> > > > > as i needed it's functionality in my applet i changed the makefiles (and
> > > > > headers) to build a shared library and install it in $PREFIX/lib
> > > > > (headers in $prefix/include/ddcci)
> > > > 
> > > > There is no problem about it. My only concern is about two applications
> > > > accessing the monitors at the same time. It could create huge problems
> > > > (particularly with ddcpci)... I think we need a mechanism to lock and
> > > > unlock the libraries, but I've no experience on it. Any idea??
> > > not only the library must be locked, but other applications also need to
> > > get informed of changes.
> > > or do you mean not allowing to run two applications at the same time?
> > 
> > An easy way of doing this thing, which doesn't requires the apps to be
> > "informed", would be:
> >  - When ddccontrol or gddccontrol run, it locks the library, so no other
> > app can access DDC/CI. (so you can't change profile in ddcc-applet)
> >  - When ddcc-applet, it doesn't lock the library, unless when it is
> > changing of profile.
> > 
> > But again, I don't know how to do this... I'll try to find
> > informations...
> > 
> 
> is it requrired that the whole library is locked, or must just be
> ensured, that only one library function is executed at a time?
> 
> i've experienced no problems so far running both apps the same time,
> exept the information they are showing getting out of sync.
> 
> what kind of problems do you expect? maybe just adding protection to
> some critical functions is enough.

Yes, you're right, locking some functions should be enough...

I'll also find a way to automatically refresh controls/profile list.

Best regards,

Nicolas