Using the X-Windows Environment

When X-Windows is invoked you are usually presented with at least one X-terminal window. By moving your mouse pointer over this window you select that window to receive the 'input focus' of the terminal. All keyboard input is directed to the window with the input focus. After the window is put in focus, you can enter commands at the shell prompt.

An important use of the setenv command is to redefine the DISPLAY variable when logging in to a remote machine. If you log in to a remote machine, then run an X-windows-based program from that remote machine, the X server needs to know where to display the window for program output. The DISPLAY variable is used for this purpose. When you login to a Xwindow based machine, the default startup files set the DISPLAY enviornment variable for you to the machine you have just logged into. If you rlogin into another machine or run a program remotely via rsh, then the DISPLAY environment variable should be set correctly. However you may run into some instances where this doesn't work properly and you need to set it manually. If you get an error like:

Can't open display:

then enter the following from the remote machine to set the DISPLAY environment variable:

setenv DISPLAY machine-you-want-to-display-on:0

After setting the DISPLAY variable, add the name of the remote machine to the list of those machines allowed to make connections with the X server with the command xhost. If remotely connected to gandalf the following would add gandalf to the list:

xhost gandalf

You can now run your X application on the remote host.

If you get an error that looks like:

Xlib: connection to "dori:0.0" refused by server Xlib: Client is not authorized to connect to Server xterm Xt error: Can't open display: dori:0.0

then you need to run xhost.

Modifying the current configuration of windows is done by moving the pointer out of all X-terminal windows (onto the background screen) and pressing the right mouse button. A window entitled 'System' will pop up, and by continuing to hold the mouse button down, and dragging the mouse towards you, you will highlight the various options that are in the window. Moving the mouse slightly to the right after highlighting any one of these options will show any further options under a given heading if further options exist.

Note that by pressing the right mouse button when the pointer is over the title bar on the top of a window, a window entitled 'Title Bar Window' appears. This window has the most of the options that are in the 'Window Options' submenu of the System window, but the options act specifically on the window whose title bar was selected.

The System window options:

1.

Window Options

• Lower
  Places the selected window on the bottom of the stack of windows.
• Raise
  Places a selected window on the top of the window stack.
• Resize
  Selecting this option allows you to change the size of any X-terminal window that you are using. After selecting this option, move the pointer over the window you wish to change and press the left mouse button. While holding the button down, drag the mouse in any direction to alter the frame size of the window. Release the left button when the window is the size that you prefer. This option also exists as the fourth icon (from the left) on the title bar. Follow the same procedure for resizing when using the icon.
• Zoom/Unzoom
  This option expands a window to the maximum screen size, and back to normal if selected again.
• Half Zoom/Unzoom
  Same as Zoom, except that window is expanded to half the screen size.
• Move
  Used to change the position of an X-terminal window. Follow the procedure for Resize (above) to drag window to new location. This option also exists as the second icon (from the left) on the title bar.
• Deiconify
  Not used. To deiconify a window, click the left button while the pointer is on the appropriate icon box in the upper right corner of your terminal screen.
• Iconify
  Removes a window leaving only its icon on the upper right part of the screen. Icon is marked with an 'X' if window it represents is not active. This option also exists as the first icon (from the left) on the title bar.
• Identify
  Display a message showing info about window selected.
• Focus
  Force input focus to be in a selected window irrespective of pointer position.
• Unfocus
  Unfocus previously Focused window.
• Kill
  Skull and Crossbones pointer that destroys the window beneath it if the left mouse button is pressed. This option also exists as the third icon (from the left) on the title bar.

2.

Active Windows
Shows a list of all windows you currently have active when you move the pointer to the right on this option. Also provides an alternate way of deiconifying windows by clicking on the window names.

3.

OpenWindows
This menu contains a series of utility programs that you can start by dragging the highlight bar over the program name, then releasing the right mouse button.

4.

Button Help
Details the mapping of mouse buttons and meta/control key combinations to functions.

5.

Open New XTERM
Opens a new default X-terminal window.

6.

Show Icon Box
Displays icon box if hidden behind other windows, or if explicitly removed via 'Hide Icon Box'

7.

Hide Icon Box
Removes icon box from view. Can be brought back into view with 'Show icon Box'

8.

TMW-Version
Version information on window manager.

9.

Show system MOTD
Displays a window with any Messages Of The Day from the system. This message will come up automatically at login, but you can look at it again with this option.

10.

Redraw all
Redraws all windows on the screen. Helpful if garbage is written on your screen for some reason. This option won't get rid of ''iebark reset '' and other system error messages, you'll need to log out and log back in again to get rid of these.

11.

Restart Window Mgr
Restarts the Window Manager. Probably not something you will ever need to do.

12.

Lock Screen
Locks your screen while displaying a moving image. Something you should do every time you leave your terminal, to prevent unauthorized access to your account. Hit a key to get the password entry screen, and enter your password to get back into your account.

13.

Logout
Logs you out if you are on a Sun Terminal. Causes a lot of trouble if you are on an RT. The proper way of logging out on an RT is to press CTRL-ALT-BACKSPACE to kill the X-Windows process, then entering 'logout' on the command line.

The Tools window options can be seen by moving the pointer away from all other windows and pressing the left mouse button. The options are a series of utility programs:

1.

Calculator
A standard calculator that you operate with the mouse.

2.

Editors
Another menu is here; move the mouse to the right to access it. Several editors (including EMACS) are listed for your use.

3.

Mail
A utility for sending mail. Many more options than command-line version.

4.

XMail
Another utility for handling your mail. Some people like this better than the previous one.

5.

Biff
Produces a mailbox icon that announces the arrival of mail by putting up the mailbox's flag and reversing icon's video.

6.

Manual Pages
A man page reader which is prettier and more powerful than command-line version.

7.

Magnify
A utility that magnifies a square region of the screen that you select.

8.

Load Monitor
Displays the CPU load on your host terminal in graphical form.

9.

Notepad
Notes can be written to this window to help you keep track of things during a login session. Notes cannot be saved to a file.

10.

Clock
Brings up a standard analog clock.

11.

Digital Clock
Brings up a standard digital clock.

12.

XArchie
A utility that lets you search through for files available by anonymous ftp.

13.

Xforecast
A utility that lets you get weather reports from around the country.

14.

XRn
A window based form of read-news (rn). Much fancier than the command-line version.

15.

Xdtm
A utility that gives you a pseudo- MS-Windows/Macintosh view of your files.

16.

Xgopher
A information retrieval system, Gopher lets you quickly find information about the University of Maine and many other sites and topics.