In the X Window System architecture, which statement correctly describes the roles of the X server and an X client?
LPIC-1 Exam 102-500, objective 106. User interfaces and desktops medium
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The options
Not correct The X server runs on the machine where the application's code executes, and the X client is the display hardware that receives the drawing output.
Wrong, and it is the inversion that catches most people. The naming is the other way round: the application is the client, the display is the server.
Not correct The X server and the X client are two halves of the same process and cannot be separated across machines.
Wrong. Separating them is the entire point of the X protocol: a client on one host can draw on a server on another host over the network, which is what X forwarding exploits.
Correct The X server runs on the machine with the display, keyboard and mouse, and applications are X clients that connect to it to draw and to receive input events.
Correct. The X server owns and serves the graphics hardware and input devices. Applications such as xterm or a browser are clients that ask that server for windows and receive keyboard and mouse events from it.
Not correct The X server is the window manager, and X clients are the toolkits such as GTK and Qt that it loads.
Wrong. A window manager (for example Openbox, Mutter or KWin) is itself just another X client, one with the special job of drawing frames and handling window placement. GTK and Qt are libraries linked into clients, not clients themselves.
Why
X is named from the point of view of the display hardware, not the application. The X server is the program that controls the screen, keyboard and mouse and offers those resources as a service; every application, including the window manager, is a client of it. This is why the machine sitting in front of you runs the server even when the program you are using lives on a remote host. Wayland deliberately drops this split: a Wayland compositor combines the display server and the window manager into one process, and clients talk to it directly.
Where this comes from
- Cited
- LPI exam objective 106.1
- What it says
- Understand the client and server model used by the X Window System.
Practise this
Reading one question is not practice. The trainer will draw a short set from objective 106 and space the ones you get wrong.
More questions on this objective
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