Xephyr

Xephyr is a command line tool used for running nested X Window System servers within the current session. It allows the creation and management of isolated display environments within a single host system. Xephyr provides a lightweight alternative for testing, development, and experimentation purposes, without the need for multiple physical machines or virtualization.

With Xephyr, users can create and run multiple X servers within a single X session, each with its own root window. This enables the simultaneous execution of different applications or desktop environments in separate isolated environments. Each nested X server behaves as an individual X11 display.

Xephyr supports various command line options, allowing users to configure the size, depth, and other properties of the nested X server. It can be initialized with a specific resolution, color depth, and screen number, among other parameters.

The command line tool also enables the usage of window managers, desktop environments, and applications specifically targeted for testing or debugging purposes. This makes Xephyr an invaluable tool for developers and software testers, allowing them to simulate different display scenarios, resolutions, and environments.

Since Xephyr runs within the current X session, it inherits all the available resources of the host system, such as input devices, graphics acceleration, and system libraries. This ensures compatibility and efficient utilization of system resources.

Xephyr can be used in combination with other command line tools, such as Xvfb (X virtual framebuffer) or Xnest, to create complex nested X server configurations. It can also be integrated into scripts and automation workflows, allowing for the streamlined testing and deployment of graphical applications.

By providing a lightweight and flexible solution for nested X server management, Xephyr empowers users to explore and experiment with different graphical environments without the need for extensive hardware or virtualization setups.