Knowledge Base

The Gnome Desktop

Gnome provides Linux computers with a graphical interface similar to Macintosh or Windows computers.

On Linux computers, many people use a shell (a text-based or command-line user interface) to run programs. However, Linux also provides several graphical desktop enironments. One of these is Gnome, which is the default on the College's Linix servers.

Gnome's interface is similar to the GUIs provided by Macintosh or Windows computers, but is also quite different in many ways. For example, it has the CentOS Icon System menu, which is used like the Windows Start Menu or the Macintosh Apple Menu. However, this menu is organized very differently, and most of the applications and utilities you willl find in it will also be very different.

Instructions for logging in using Gnome

Running Graphical Applications in Gnome

A large number of graphical programs have been written to take advantage of the Gnome desktop (or, more generally, X Windows). Some of these are also available on Windows and Macs and look very similar in all environments; Mathematica is a good example. Some of these programs are graphical versions of software that was originally written for use with shells, e.g. the text editor Emacs. Here are some sample instructions for running a graphical application in Gnome:

To start up Mathematica:

  1. In the lower left corner of the screen, click on the CentOS Icon System menu.
  2. Select the menu item Gnome Programming Icon Programming.
  3. Select the menu item Gnome Mathematica Icon Mathematica.

 

To start up Emacs:

  1. In the lower left corner of the screen, click on the menu CentOS Icon System.
  2. Select the menu item Gnome Programming Icon Programming.
  3. Select the menu item Gnome Emacs Text Editor Icon Emacs Text Editor.

Running Command-Line Applications in Gnome

There are still many Unix programs, some quite essential, that are only usable with a text or command-line interface, known as a shell. Gnome lets you start up any number of virtual terminals to run such programs. Please note that you can also do the same thing remotely with SSH , so this is not a reason to use Gnome unless these programs generate graphical output (e.g. some Java programs), or if you're already using Gnome for some other reason. To start a virtual terminal in Gnome, follow these instructions:

To start up a Terminal:

  1. In the lower left corner of the screen, click on the menu CentOS Icon System.
  2. Select the menu item Gnome Accessories Icon Accessories.
  3. Select the menu item Gnome Terminal Icon Terminal.

Many Gnome graphical applications can also be started from a terminal window, e.g. you can type in "mathematica &" or "emacs &" and the return key. The purpose of the "&" is to detach these programs from the terminal window, otherwise they will prevent it from being used for other activities.

Logging Out of Gnome

 

To log out of Gnome:

  1. In the lower left corner of the screen, click on the menu CentOS Icon System.
  2. Select the menu item Gnome Logout Icon Log Out username.
  3. In the dialog Log out of this system now?, click on the button Log Out.

If you are connecting to Unix using NX , then you have the option to disconnect rather than log out of Gnome. This will leave your applications running for when you reconnect. To disconnect, simply close the NX window, and when asked, click on the button Disconnect.