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tech291083
14th May 2007, 01:28 PM
Hi,

I have been reading a bit aboyt the X Window system adopted for Linux and came across this web page.

http://en.wikipedia.org/wiki/X_Window_System


It details the whole idea in a very technical language suited to the pros. But if I am to sum it up as to what exactly it means is, would be

the X Window System (commonly X11 or X) is a networking and display protocol which provides windowing on bitmap displays.

As per the exact first few lines on the page itself. But as far as I understand, it is nothing else but an API just like any other API tha allows programmer to develop softwares that can ultimately be able to talk to the operating system of any kind acting as an intermediary layer. Is this the right path I am on? Here I am moving away from the very concept of a protocol and api though which both are totally different thing as I understand.. Thanks....

Phobeus
14th May 2007, 02:09 PM
I think the answer heavily depend on the technical level you wish. The article itself does explain it quite nice. The X Window system or commonly often just "x server" is a graphic layer on top of the system allowing to interact with input devices and drawing primitive graphic items (lines, rectangle) etc. So in the unix world the graphic layer is running on top of the system itself and this allows you switching to text mode or restarting the server without restart the operation system itself.

However the X server itself is not quite usefull... it just provides an interface to mouse, keyboard and drawing operations. On top of the x server a so called "window manager" is running, allowing to draw and interact with the well-known windows. KWin (KDE), Metacity (GNOME) and the modern compiz/beryl are good examples. So if somebody is asking me what the x server is, I am often just say: It's that part of software allowing you to run a graphical interface.

markkuk
14th May 2007, 02:16 PM
As per the exact first few lines on the page itself. But as far as I understand, it is nothing else but an API just like any other API
No, at the core X is a networking protocol just as the article says. XLib and other APIs are means for accessing that protocol but you could use the the protocol directly through sockets.

tech291083
14th May 2007, 02:21 PM
I think the answer heavily depend on the technical level you wish. The article itself does explain it quite nice. The X Window system or commonly often just "x server" is a graphic layer on top of the system allowing to interact with input devices and drawing primitive graphic items (lines, rectangle) etc. So in the unix world the graphic layer is running on top of the system itself and this allows you switching to text mode or restarting the server without restart the operation system itself.

However the X server itself is not quite usefull... it just provides an interface to mouse, keyboard and drawing operations. On top of the x server a so called "window manager" is running, allowing to draw and interact with the well-known windows. KWin (KDE), Metacity (GNOME) and the modern compiz/beryl are good examples. So if somebody is asking me what the x server is, I am often just say: It's that part of software allowing you to run a graphical interface.

Thanks a lot first of all.

Very polite and relevant explanation as far as I go. You are very right in making it clear to me that it is nothing but a layer that wraps the main os element ie kernel and sits below another layer called the window manager which allows the interaction between users and computer as the ultimate objective. This is the way I want to understand the whole idea the layer based/component based clarification, just like human body as a whole has many components such as the heart, lungs, kidney and brain, who have their jobs well defined. Tell me one more thing, as I have oftern come across people's questions regarding their inability to start the x-server on Linux. So as far as I understand now, it is by default already on when you are starting the pc. Right? And it is off for some reason you might not be able to see the windows, menus etc. Tell me more and thanks again for the kind help offered.....

tech291083
14th May 2007, 02:23 PM
No, at the core X is a networking protocol just as the article says. XLib and other APIs are means for accessing that protocol but you could use the the protocol directly through sockets.

Thanks a lot mate..