x11utils

X11utils, commonly referred to as x11utils, is a collection of small command-line programs that interact with the X Window System. The tools are designed to query information about an X server, inspect and manipulate window properties, manage client connections, and adjust server settings. They are typically packaged as x11-utils or xorg-x11-utils in many Linux and BSD distributions as part of the X.Org suite. The exact toolset varies by release, but the package generally includes utilities such as xprop (read or set window properties), xdpyinfo (display information), xwininfo (window information), xlsclients (list X clients), xhost (control host access), xset (alter server defaults like keyboard and pointer behavior), xsetroot (change root window parameters), and xkill (terminate a client by its window).

These utilities are valued by developers, administrators, and window-manager authors for debugging, scripting, and configuring an X environment. They are often used in shell scripts to obtain IDs, properties, or status information needed to automate tasks or diagnose display issues. The x11-utils package is part of the broader X.Org ecosystem and remains widely available across Unix-like systems that implement the X Window System.