[Openicc] Profile installation and association for Linux/Unix/X11

[Graeme Gill]

Kai-Uwe Behrmann wrote:

> What would be needed for applications is a way of registering callbacks 
> to obtain notification at a root window Xatom change.

Right, but the application side is not my concern, making the Xatom change
in response to a monitor being plugged in is. Applications can register
for RootWindow and RROutputProperty change events.

> In contrary a daemon might eigther poll or wait in a endless loop for 
> events.

With XRandR the daemon registers for RRScreenChangeNotify and
RROutputPropertyChange events, and waits for an event. On the event it
can check whether the configuration and/or EDID has changed, and install
the appropriate ICC profile in the Xatom (by consulting the monitor<->profile
association in the installed profile config files), and also update the monitor
video luts to the profile calibration.

For non-RandR it could select PropertyChangeMask, and check the
root window Xatom for a change in the EDID.

(at least, that's the sketch).

Graeme Gill.