@section(Appendix A:  VAXstation Terminals)

A VAXstation terminal looks like Figure 1.  Attached to it, in addition
to the keyboard, is a little puck with buttons on it called a @b(mouse)
(Figure 2).

The VAXstation terminals run something called
the @b(X window system).  A window system lets you divide up the
screen into sections called @b(windows).  Each window can behave like
a regular terminal.  Hence, you can do more than one thing at once:
a different thing in each window.  For example, in one window you
might be reading your mail, while in another you edit a file, while
in a third you are running it through the @i(scribe) formatter.
Windows can overlap.  See Figure 3. 

You move from window to window
by rolling the mouse around on the tabletop.  As you do this, you
will see a @b(mouse cursor) moving around on the screen.  Whichever
window the mouse cursor is "in," that's the window that will get
the characters you type on the keyboard.

@subsection(Login)

VAXstations have the same login banner as other terminals.  If the
screen seems to be blank, hit the SHIFT key or wiggle the mouse,
and the login window will appear:
@begin(example)
Athena Login Server (NESSUS.MIT.EDU:ttyv1 5:36 pm on Mon 26 Aug 1985)


Machine name:
@end(example)
To login:
@begin(enumerate)
See the two circled parts of the login banner above?  Write down what
your VAXstation shows in the same place.  You @i(need) this.

Make sure that
the I-shaped mouse cursor is inside the login window. If it isn't,
the terminal will ignore everything you type.  When the mouse cursor
is outside a window, it looks like an "x". 

Login as usual.

Once logged in, type this:
@example[setenv  DISPLAY  @i(nessus:1)]
This is vital.  Without it, you will not be able to make windows
on your terminal.  Copy it exactly.  "setenv" is all lowercase and all one
word.
"DISPLAY" is all uppercase.  Where the example says "nessus:1", substitute
the name and number your VAXstation showed before you logged in--e.g.,
teela:0, or maybe demeter:3, etc.   Run this third piece all together,
as shown.
@end(enumerate)

@subsection(Making Windows)

When you first login, you only have one window.  From that window, you create
additional windows.  

To create a terminal window:
@begin(enumerate)
Type:
@begin(example)xterm &
@end(example)
The "&" is important.  Be sure to add it.  The system will reply
with something like, "[1] 15832".

The mouse pointer will change to a cross with a
thin, spectral window outline.  Move the cross
with the mouse to where you want the upper left corner of the window
to be.

You now pick the window's size by pressing one of the mouse buttons:
@begin(description)
small window@\the left mouse button

big window@\the right mouse button

variable size window@\hold down the center mouse button and roll the
mouse.  Let go at the size you want.
@end(description)
@end(enumerate)

If you didn't setenv DISPLAY right, you'll get an error message "can't
connect to display server..."  Possibly your window will show up
on someone else's VAXstation.

@subsection(Moving Windows Around)

After you make a window from your login window, you'll want to start up
a program called @b(xwm).  This is the @b(window manager) program.  Without
@i(xwm), you won't be able to move the windows around, nor shuffle
them like papers stacked on a desk.

To start a window manager, type:  @b(xwm &) (Again, don't forget the "&".)
The only response will be something like "[2] 2665".  If you
don't get a prompt back shortly, you probably forgot the "&".


The X functions are listed below.
To perform any X function you
must hold down the key labeled SYMBOL (or COMPOSE CHARACTER)
with one hand, and manipulate the mouse
with the other.  The SYMBOL key is the key underneath
the SHIFT and '<' keys at the left of  the space bar.

@begin(description)
Move a window@\"Click" and hold the right mouse button down.
Move the mouse, and the window will drag along with it.  Depress the button.
This will also bring the window to the top if other windows have been
stacked on top of it.

Bring a window to the top@\Just click the right mouse button on the window
you want on top.

Push a window to the back@\Click the left mouse button on the window you
want pushed to the back, underneath the others.

Resize a window@\To change the size of a window, click and hold the
middle button on the window to be changed.  The mouse pointer will
change to a cross with arrows on the ends.  A small window showing
the size of the @p(xterm) window will appear, and the size will
change as you move the mouse to the desired
size.

Iconify a window@\An "icon" is a small symbol that represents a window.
To create an icon, click and hold the left mouse button on the window you
want to iconify, and then move the mouse to the desired location for the
icon.  The window will go away and be replaced by a small box that says
"xterm".  Other programs besides @p(xterm) may have different icons.

Restore an iconified window@\To bring back a window that has been
iconified, just move the mouse pointer to the icon and click the middle
button.

@end(description)

@subsection(Removing Windows)

To get rid of a window, type @b(exit) to the system prompt 
in the window you want to go away.

If you logout of your original login window, all windows will go away.


@subheading(More Advanced Information)

This information is enough to get you started with windows.  The "Hardcopy
Graphics Output" chapter tells how to get VAXstation "screen dumps."
There are many X programs besides @i(xterm) and @i(xwm).  Take the
Athena Minicourse on the X window system to learn more about X.
There will be an @i(Essential X) later in Spring term 1986.