x11-xserver-utils

About x11-xserver-utils

From Debian's package description

An X client is a program that interfaces with an X server (almost always via the X libraries), and thus with some input and output hardware like a graphics card, monitor, keyboard, and pointing device (such as a mouse).

This package provides a miscellaneous assortment of X Server utilities that ship with the X Window System, including:

• iceauth, a tool for manipulating ICE protocol authorization records;
• rgb;
• sessreg, a simple program for managing utmp/wtmp entries;
• xcmsdb, a device color characteristic utility for the X Color Management System;
• xgamma, a tool for querying and setting a monitor's gamma correction;
• xhost, a very dangerous program that you should never use;
• xmodmap, a utility for modifying keymaps and pointer button mappings in X;
• xrandr, a command-line interface to the RandR extension;
• xrdb, a tool to manage the X server resource database;
• xrefresh, a tool that forces a redraw of the X screen;
• xset, a tool for setting miscellaneous X server parameters;
• xsetmode and xsetpointer, tools for handling X Input devices;
• xsetroot, a tool for tailoring the appearance of the root window;
• xstdcmap, a utility to selectively define standard colormap properties;
• xvidtune, a tool for customizing X server modelines for your monitor.

From Debian's description of the x11-xserver-utils package, under that package's license.