Xorg

Xorg [:display_number] [option ...]

Example: Xorg :1 -configure

-configure
    Generates a new xorg.conf configuration file, often used for initial setup or troubleshooting.

-config
    Uses the specified xorg.conf file instead of the default paths.

-logfile
    Redirects server output and errors to the specified log file.

-depth
    Sets the default color depth for the display (e.g., 24 for true color).

-retro
    Starts the server with a monochrome, retro-style display, primarily for debugging.

-version
    Prints the X server version information and exits.

-ac
    Disables access control, allowing any host to connect to the X server. Highly insecure.

-dpi
    Sets the screen's Dots Per Inch (DPI) value, affecting font and element sizing.

Xorg is the open-source implementation of the X Window System, providing the fundamental building blocks for graphical user interfaces on Linux and other Unix-like operating systems. It acts as a server that manages graphical displays, input devices like keyboards and mice, and communicates with client applications (graphical programs).

Its primary function is to draw windows, text, and images on your screen, and to relay input events from your devices back to the applications. While users typically interact with Xorg indirectly through a display manager (like GDM, LightDM, or SDDM) or by using commands like startx, it's the core component that enables the visual desktop environment you see. Xorg supports various graphics drivers and input methods, making it highly versatile for different hardware configurations. It relies on configuration files (traditionally xorg.conf or snippets in xorg.conf.d) to define display settings, input device mappings, and other server behaviors, although modern Xorg often auto-detects most settings.

Xorg typically requires root privileges to operate, as it directly interacts with hardware. It is rarely invoked directly by users, but rather by display managers or helper scripts like startx.

Its configuration can be complex, though modern Xorg versions often manage well with auto-detection. Manual configuration via xorg.conf is still possible but less common.

Note that Xorg is gradually being replaced by Wayland as the default display server on some Linux distributions, representing a shift in graphical architecture.

The primary configuration file for Xorg is xorg.conf, though modern systems often use modular configuration files located in /etc/X11/xorg.conf.d/. These files define screen resolutions, monitor settings, input device mappings, and driver options.

Xorg logs its operations, warnings, and errors to files typically found at /var/log/Xorg.0.log (for the first X server instance). These logs are invaluable for diagnosing display and input device issues.

Xorg traces its roots back to XFree86, a widely used open-source implementation of the X Window System that emerged in the early 1990s. In 2004, due to licensing disagreements within the XFree86 project, the X.Org Foundation was established, and Xorg was forked from XFree86 4.4 RC2. This new project quickly gained traction and became the de facto reference implementation for X11.

Over the years, Xorg has seen significant development, including improved hardware support, modularity, and better auto-configuration capabilities, reducing the need for manual xorg.conf files. While still widely used, its role is evolving as new display server protocols like Wayland gain prominence.

startx(1), xinit(1), xrandr(1), xset(1), xorg.conf(5), xdm(1)