xdg-screensaver

xdg-screensaver { activate | reset | lock | status | suspend | resume }

activate
    Triggers the screensaver, typically blanking the screen or starting the screensaver program.

reset
    Simulates user activity, resetting the screensaver idle timer and preventing its immediate activation.

lock
    Activates the screensaver and locks the session, requiring a password to regain access.

status
    Reports the current state of the screensaver. Returns 0 if active, 1 if inactive, and 2 if the status cannot be determined or is unsupported.

suspend
    Temporarily halts automatic screensaver activation, often used by applications displaying fullscreen content like videos.

resume
    Restores automatic screensaver activation after a prior suspend command, allowing it to engage based on idle time.

xdg-screensaver is a utility included in the xdg-utils package, designed to provide a desktop-environment-independent way for applications to interact with the system's screensaver. It abstracts the underlying mechanisms, whether they involve D-Bus calls to gnome-screensaver or kde-screensaver, or direct commands to xset for simpler setups. This standardization allows applications to control the screensaver without needing to know the specifics of the user's desktop environment (like GNOME, KDE, XFCE, MATE, LXDE, etc.).

Its primary functions include activating the screensaver, resetting the idle timer to prevent activation, locking the screen, querying the current screensaver status, and informing the screensaver to temporarily suspend or resume its automatic behavior (useful for full-screen video playback). By offering a common interface, xdg-screensaver simplifies application development, ensuring consistent behavior across diverse Linux desktop setups. It gracefully handles scenarios where a screensaver might not be installed or configured, providing appropriate exit codes for error handling in scripts.

xdg-screensaver relies on the desktop environment's D-Bus interfaces or specific commands. If no compatible screensaver is installed, configured, or the desktop environment doesn't expose the necessary interfaces, some commands might not function as expected or return an exit code indicating an unsupported operation. It primarily manages automatic screensaver behavior rather than direct configuration of screensaver settings (like theme or delay). Scripting with this command should always check its exit codes for robust error handling.

xdg-screensaver provides informative exit codes for scripting: 0 for success, 1 for general errors, 2 if the requested operation is not supported by the desktop environment or status cannot be determined, and 3 for invalid command-line arguments. Checking these codes is crucial for reliable automation.

This command exemplifies the xdg-utils philosophy of abstracting desktop-specific implementations. It attempts to communicate with various screensaver daemons (e.g., gnome-screensaver, kde-screensaver, xfce4-screensaver) using their preferred methods (often D-Bus), falling back to simpler X Window System commands like xset if no sophisticated screensaver is detected. This ensures broad compatibility.

xdg-screensaver is a component of the xdg-utils package, developed under the freedesktop.org initiative. This initiative began to create common standards and tools for Linux desktop environments, addressing the fragmentation that arose from distinct development paths of GNOME, KDE, and others. xdg-utils (and thus xdg-screensaver) emerged to provide a unified API for common desktop tasks, abstracting away desktop-specific implementations. It allows applications to perform actions like opening files, managing MIME types, or controlling the screensaver, without needing to detect and adapt to the specific desktop environment the user is running. Its development has focused on robustness and wide compatibility, evolving with desktop environment standards.

xdg-open(1), xdg-settings(1), xdg-mime(1), xdg-desktop-menu(1)