13.1. Configurazione del server X11
La configurazione iniziale dell'interfaccia grafica può essere complicata a volte; schede video molto recenti spesso non funzionano alla perfezione con la versione di X.org fornita nella versione stabile di Debian.
A brief reminder: X.org is the software component that allows graphical applications to display windows on screen. It includes a driver that makes efficient use of the video card. The features offered to the graphical applications are exported through a standard interface, X11 (Stretch contains version X11R7.7).
Current versions of X.org are able to autodetect the available hardware: this applies to the video card and the monitor, as well as keyboards and mice; in fact, it is so convenient that the package no longer even creates a /etc/X11/xorg.conf configuration file.
La configurazione della tastiera è attualmente impostata in
/etc/default/keyboard. Questo file è usato per configurare sia la console testuale sia l'interfaccia grafica, ed è gestito dal pacchetto
keyboard-configuration. Dettagli sulla configurazione della disposizione della tastiera sono disponibili in
Sezione 8.1.2, «Configurare la tastiera».
Il pacchetto xserver-xorg-core fornisce un server X generico, come usato dalle versioni 7.x di X.org. Questo server è modulare e usa un insieme di driver indipendenti per gestire i molti diversi tipi di schede video. L'installazione di xserver-xorg assicura che sia il server che almeno un driver video siano installati.
Note that if the detected video card is not handled by any of the available drivers, X.org tries using the VESA and fbdev drivers. VESA is a generic driver that should work everywhere, but with limited capabilities (fewer available resolutions, no hardware acceleration for games and visual effects for the desktop, and so on) while fbdev works on top of the kernel's framebuffer device. Nowadays the X server runs without any administrative privileges (this used to be required to be able to configure the screen) and thus its log file is now stored in the user's home directory in ~/.local/share/xorg/Xorg.0.log (whereas it used to be in /var/log/Xorg.0.log for versions older than Stretch). That log file is where one would look to know what driver is currently in use. For example, the following snippet matches what the intel driver outputs when it is loaded:
(==) Matched intel as autoconfigured driver 0
(==) Matched modesetting as autoconfigured driver 1
(==) Matched vesa as autoconfigured driver 2
(==) Matched fbdev as autoconfigured driver 3
(==) Assigned the driver to the xf86ConfigLayout
(II) LoadModule: "intel"
(II) Loading /usr/lib/xorg/modules/drivers/intel_drv.so
