perm filename TEACH.DM[UP,DOC]2 blob sn#346003 filedate 1978-04-04 generic text, type C, neo UTF8
COMMENT ⊗   VALID 00023 PAGES
C REC  PAGE   DESCRIPTION
C00001 00001
C00003 00002	    You are now looking at page 2 of TEACH (see top line with asterisks).
C00008 00003	General remarks (come back later if this seems confusing).
C00011 00004	The window display
C00012 00005	PAGE changing commands.
C00017 00006	How to EXIT and how to ENTER a file.
C00019 00007	A brief review
C00021 00008	WINDOW and CURSOR moving cammands.
C00031 00009	EDITING.  The LINE-EDITOR and how to add text.
C00035 00010	More on the line editor
C00037 00011	Simple line-editing commands.
C00043 00012	More editing commands.  Insertions and deletions.  αβ<CR>  αI  α<cr>  αβD
C00048 00013	PAGING. Introducing and deleting PAGE MARKS.  EXTEND commands.
C00053 00014	File switching commands.  α?  αH  αε αλ and α∃   File switches.
C00063 00015	Line marking. αβM and αM
C00066 00016	ATTACH and COPY.
C00072 00017	FIND commands. Single page, multipage and directory searches.
C00083 00018	Substitution commands.
C00086 00019	Text justification. XJUST,XJFILL XSJFILL and XJGET
C00096 00020	Margin fixing commands. XALIGN<cr> XCENTER<cr> XINDENT<cr> → and ←
C00100 00021	Some other EXTEND commands.
C00106 00022	System commands to evoke E.
C00110 00023	Summary.
C00112 ENDMK
C⊗;
    You are now looking at page 2 of TEACH (see top line with asterisks).
Page 1, the "directory" page, is automatically prepared by E.

ABREVIATIONS used in TEACH to characterize commands to E.
   α     means hold the "CONTROL" key down while typing a character.
   β     means hold the "META" key down while typing a character.
   αβ    means hold both "CONTROL" and "META" keys down while typing.
   ⊗     means hold either the "CONTROL" key alone or both "CONTROL"
	   and "META" keys down while typing.
NOTE!!  The words "control" and "meta"  as used in this document refer  to
the Stanford keyboard.  On a  Datamedia keyboard, "control" means to  hold
down the  EDIT  key while  typing  the  character; "meta"  means  to  type
EDIT-NUL (hold down EDIT while typing NUL) and then type the character.
    A line starting with !! is an instruction that you are to follow.

   !!    Type αW (pronounced CONTROL W) (hold EDIT down and type W).
		(Use this command to get to the next window.)

Remember, when you see αW you should think "CONTROL-W" and type EDIT-W.
When you see βW you should think "META-W" and type EDIT-NUL then W.
The CTRL key is NOT used for CONTROL characters, but for funny characters
like π or λ.  If you see π, think "pi" and type CTRL-G.

   <cr>    carriage RETURN key.			<lf>    LF (line feed) key.
   <tab>   TAB key.				<alt>   ESC key (altmode).
   <bs>    DEL key (Back-Space).		<form>  ↑L key (form-feed).
   <vt>    CTRL-K (vertical tab).		<clear>	the CLEAR key.
   CURRENT means the current line (normally where the blinking cursor is).

Remember that on a Datamedia the characters β ∨ and ≡ must be "quoted" by
typing NUL first: if you see α∨ think "CONTROL-OR" and type NUL then EDIT-HOLD.

    !! Type αW again to see the next window.  (We won't mention this again!)

    Most commands are single characters typed with one or both of the  two
special keys held down as specified by α, β or ⊗ as defined above.  When a
number is shown in a command, this  is by way of example, and any  desired
decimal number may be used.

Hints for Datamedia users: at Stanford it is just as easy to type αβ as it
is to type α since these are two shift-like keys right next to each other.
But on a Datamedia it's a pain to type <meta>, so when you see a ⊗ command
(meaning you can type it either way) just think of it as a α command.  But
if the command description  says αβ explicitly, you  have to type it  that
way.  In reading this manual, don't confuse ⊗ (a funny character,  CTRL-V)
with the letter x.  ( x⊗x⊗X⊗X⊗ )

    Typing ordinary characters will cause you to enter the LINE-EDITOR and
can easily lead to the overwriting  of desirable text, so be careful.   If
you do make a mistake or get confused, type <alt> before you type a <cr>.

   !!    If you would like to review these definitions--you should feel
	   confident about things like "control" and "meta" and "<alt>"
	   before continuing--type αL to return to the top of the page.

   !!    Type αP (pronounced CONTROL P) (hold CONTROL down and type P).
		(Use this command to get to the next page.)
General remarks (come back later if this seems confusing).

    E is a page oriented editor designed for use with a display  terminal.
It brings one page of the text into core, as requested, and it displays  a
portion of this  page as if through a window.   A line pointer, namely, an
underscoring cursor, marks the position in the  text where  editing is  to
occur.  Special commands allow you  to go from page  to page, to move  the
window up or down on the page and  to move the line pointer and cursor  as
desired.

    E does not make a separate disk  copy of the file being edited  unless
requested to do so by the use  of a special command (described later),  so
take care or you may damage a file, even one belonging to someone else.

    E achieves its speed (1) by using  the system line editor and by  only
changing the core copy of the text  on the completion of a line edit,  and
(2) by updating the disk copy of the page only on the completion of a page
edit (automatically effected by moving to another page).

    Always remember  that the  text  shown on  the  display may  not,  and
usually does not, mirror the true state of the actual text on the disk.

    E is best understood by recognizing  that it operates in a variety  of
different modes  and that  many commands  are appropiate  only to  certain
modes or, worse yet, that they  may mean quite different things  depending
upon the mode that E is in at the time that the command is given.

    The dominant mode is  the NORMAL mode.  This  allows for page,  window
and line-marker  movement  commands and  commands  which enter  the  other
modes.  You will first learn some normal-mode commands.

    !!   Type αP or αβP for the next page.  DO THIS NOW.

The window display

    Notice the rows of asterisks at the top and bottom of this page.
These two lines delimit the text in the editing window.  Above the
window is the who line area, and below the window are three lines used
to echo and acknowledge the commands you type.

    !!   Type αP or αβP for the next page.  DO THIS NOW.
PAGE changing commands.

    You are now looking at a longer page than before. Note two things:

1  The header line contains asterisks, the  page number and the file name.

2  A trailer line  contains dots, where formerly there  were asterisks,
along with some suplimentary information which will be explained later.

    The asterisks  mean that  you are  seeing the  page through  a  window
starting at the top  of the page,  while the dots mean  that there is  yet
more on the page than that shown.

    Most page-changing  commands  are  single characters  typed  with  the
CONTROL key held  down or with  both the  CONTROL and the  META keys  held
down. They may take modifiers as shown below.  Examples:

   ⊗P       Go to the next PAGE. (You have done this several times).
   ⊗-⊗P     Back up to the previous page. !! Try this and then return.

   ⊗+⊗7⊗P   Go forward 7 pages if possible, otherwise to the last page.
   ⊗-⊗3⊗P   Go backward 3 pages if possible, otherwise to the first page.

   ⊗7⊗P     Go to page 7 if possible, otherwise to the last page.

    !!  If you are sure  that you know these  commands, skip around a  bit
and come back  here by typing  ⊗5⊗P.  Note  that the directory  on page  1
lists the first line of each page.

    To get to see another windowful of a long page one types <form>,  that
is, depress the FORM key. (Note that no control keys are required.)
    !!  So type <form> now.

    If somehow you  failed to  understand what happened,  then type  <vt>,
that is, hold down CTRL and type K, and you will go back a windowful.

    !!  So do this now and then come back here.  Do this several times.

    When you tire of this you might  note that dots have now replaced  the
asterisks in  the  header  line.  Some  additional  information  has  also
appeared in this line, to  wit, a record of the  line number of the  first
line that now shows on the window.  At this time this number is 33.

    !!  Type <form> again and see what happens to the line number at the top.

    Now turn  your attention  to the  trailer line  which is  now seen  to
contain asterisks indicating that we now see to the end of this particular
page, which is  still a rather  short one.  The  information on this  line
tells you that the cursor is pointing to line 49 as it does and that there
are 62 lines on this page, further that you are looking at page 5 and that
there are 23 pages in  this file.  We will ignore  the rest of the of  the
information for the time being.

    By this  time, you  will have  also observed  some rather  nonsensical
information below the trailer line which is,  in fact a record of some  of
the commands that you have been typing and some acknowledgements of  these
commands.  Form a practice  of watching this information  to be sure  that
your commands are properly acknowledged before you type too far ahead.  At
the moment about the  only thing to  observe is that  the <form> and  <vt>
commands are echoed in a rather funny way.

    !!  So type ⊗P as you did earlier.
How to EXIT and how to ENTER a file.

    But maybe you have had enough for one session and would like to  quit.
As mentioned earlier you have created a  special file on your own area  by
the name of TEACH and you will be able to re-enter this file by typing the
system command ET TEACH  followed by the "return"  key.
		Remember this  ET TEACH<cr>.

    And now to quit, simply  type ⊗E , that is,  type the letter "E"  with
either the <control> key or both <control> and <meta> keys depressed.

    !!  If you want to quit now, do so,  otherwise continue and come  back
here when you are ready to quit, to make sure you know how to resume.

    If you want to  start a new file  say one named FOO,  you type to  the
system the command  CET FOO<cr>.  Having  created such a  file and  having
left it, you can, of course, reenter it by the command ET FOO<cr>.

    If you should get confused and try to create a new file with the  same
name as one that you  already have, the editor will  warn you of this  and
allow you to either correct your mistake  or, if you want, to replace  the
old file by a newly created one.

    !! If you're not tired, type αP for the next page.
A brief review

The commands that you have learned are:  (Remember what ⊗ means)

⊗P	Go to the next page.		⊗-⊗P	Go back a page.
⊗+⊗3⊗p	Go forward 3 pages.		⊗-⊗3⊗P	Go back 3 pages.
⊗7⊗P	Go to page 7.			⊗∞⊗P	Go to the last page.
<form>	Go to the next windowful.	<vt>	Go back a windowful.

⊗E	Terminate an editing session.

And the system commands:

CET BAZ		Create a new file "BAZ" (assuming you want such a file).
ET TEACH	RE-ENTER  the file named TEACH on your own area.

    !! Go to the next window
    Since this page was  only slightly longer than  a windowful, you  have
had the opportunity of observing that the command <form> only advances the
window enough to get to the end of the page.  If you try it again now  you
will also observe that it does not cross page boundaries.

!!  Type <form> several times and observe what happens to the cursor.

!!  Now try typing α<form> (EDIT-↑L).
WINDOW and CURSOR moving cammands.

   But first, are you sure that you read all of the previous page?
!! To make sure type α<vt> to back up a windowful over the page boundary.

So two other useful commands are:

α<form>		Get a new windowful, crossing a page boundary if the old
		windowful is at the end of a page and if there is another
		page in the file.
α<vt>		Back up a windowful, crossing a page boundary if the old
		windowful is at the beginning of a page  and  if there is
		an earlier page in the file.

Now a new subject,- that of CURSOR moving.

    If you have been observing the cursor to the left, you will have noted
that it has usually, but not always, pointed to the first or the last line
on the window.  This cursor points to the CURRENT line, i.e. the line that
would be edited were you to enter the LINE-EDIT mode.  For convienence, we
will call this line the "cursor line".

    While in the NORMAL mode, as we  now are (or at least should be),  the
command <cr>, that is  hitting the "return" key,  will cause the cursor to
move down a line and the command <bs> will cause it to move up a line.

    Both of these  commands can  take arguments which  are simply  decimal
numbers typed  ahead  of  the  command itself,  but  NOTE  CAREFULLY,  the
arguments MUST be typed with the control key depressed, that is to say the
EDIT  key on a  Datamedia,  while the  commands themselves,  that is,  the
<return> or <bs> are typed without control keys.

The following commands can then be added to our list:

<cr>	Move the cursor down a line.	<bs>	Move the cursor up a line.
⊗4<cr>	Move the cursor down 4 lines.	⊗3<bs>	Move the cursor up 3 lines.

To these we can also add:

⊗>	The same as ⊗4<cr>.		⊗<	The same as ⊗4<bs>.
⊗2⊗>	Move the cursor down 8 lines.	⊗2⊗<	Move the cursor up 8 lines.

⊗≥	Move the cursor down half a windowful.
⊗≤	Move the cursor up half a windowful.

⊗∧	Move the cursor to the top of the window.
⊗∨	Move the cursor to the bottom of the window.

Remember that ∨ is one of the characters  which must be preceded by NUL on
a Datamedia to avoid its special meaning (HOLD), so ⊗∨ means you must type
NUL then EDIT-HOLD.

!!  It may be well to stop here and go through your repertoire of commands.

    You will observe that  the cursor moving commands will sometimes  also
move the window,  should  this be  necessary to  prevent  the cursor  from
leaving the window.  When this happens the window will usually be adjusted
so that the cursor line will be at the middle of the window.

More window moving commands.

    Having moved the cursor to a line of interest you may wish to position
the window without moving the cursor with respect to the text.  There  are
several commands designed for this purpose.  The more useful ones are:

⊗J	JUMP the window so that the cursor line will be at the top of the
	window.
⊗0⊗J	Jump the window  so that the cursor line will be in the middle of
	the window.
⊗-⊗J	Jump the window  so that the cursor line will be at the bottom of
	the window.

    Alternatively, you may want to see a few lines more at the top or  the
bottom  of the window  and would prefer that the  cursor not be moved with
respect to text but you are willing for this to happen if the cursor would
otherwise go off the screen.  The commands to do this are:

⊗T	Show 4 more lines at the top of the window.
⊗B	Show 4 more lines at the bottom of the window.

    !!  Try  these  commands  now.   You  will  observe  their  action  is
inhibited when they are given near the page boundaries.

    When you start trying to actually edit  a file you will find that  you
will need just about all of the commands that have been described.

Line numbers and their use.

    E is not primarily a line-number oriented editor.  However, there  are
times when it is desirable to get to some specific line on a page, perhaps
you have tried to compile a program and the compiler has given you a  list
of errors in terms of the pages and lines on which they occur.

    Just as you can get to any page, say page 6, by typing ⊗6⊗P , you  can
type ⊗2⊗9⊗L  to get  to  line 29  on the  current  page.  The  command  ⊗L
(without an argument) gets you to line 1 and the command ⊗∞⊗L will get you
to the bottom row of asterisks at the end of the page.  Relative arguments
may also be used with the L  command, but you will find that the  commands
<cr>, <bs>, ⊗>, ⊗<, ⊗≥ and ⊗≤ are usually much more convenient.

    Note that the  P command  without an  argument implies  the next  page
while the L command without an argument implies line 1.  These conventions
are arbitrary, but  once you  get used  to them  you will  find them  very
convenient.

The most useful line-number commands are:

⊗L	Go to line 1 on the page.  This is the fastest way to get to the
	start of the page.

⊗3⊗5⊗L	Go to line 35 on the page.

⊗∞⊗L	Go to one line beyond the end of the page. The cursor will point
	to the row of asterisks.   This is the fastest way to get to the
	end of the page in a position to add more text.

    E also  allows you  to move  directly to  any designated  line in  the
window, by means of the following commands.

⊗∧	Go to the first line of text in the current window.

⊗4⊗∧	Go to the 4th line of text from the top of the current window.

⊗∨	Go to the last line of text in the current window.

⊗3⊗∨	Go to the 3rd line of text from the bottom of the current window.

    !!  Try skipping around by asking  for specific lines by number.   You
will observe that the cursor will simply  move to the specified line if it
is on the window. If a shifting of the window is required, then the cursor
line will usually be in the middle of the window.

    It will pay to  become very conversant with  all of these commands  so
that you can minimize the number of key strokes that you will need to  get
to any desired location in your text.  This will save your time,  minimize
the chances of error and greatly reduce the load on the system.

    You have already observed that the trailer line always tells the  line
number of the CURRENT line i.e. the  line to which the cursor is pointing.
There is a special command ⊗XLINCNT<cr> that causes E to supply some more
information about this line and about the current page.  !! Try it.
EDITING.  The LINE-EDITOR and how to add text.

   You enter the LINE-EDIT mode simply by starting to type.

    In other words,  typing a  character without  a CONTROL  or META  key,
(almost any character key except for certain non-printing keys) will cause
that character to appear in the  line where the cursor is pointing at  the
time.  If you are in  the NORMAL mode, when you  start to type, the  typed
character will overwrite the first character in the line.  As you continue
to type additional characters will be overwritten.

    Remember- If you make a mistake  or get confused, the safest thing  to
do is to  type <alt>  . If  you do  this, while  in the  line editor,  the
corrections that you have just made will go away.

Adding text at the bottom of the page:

    Perhaps the simplest thing to do is  to add text at the bottom of  the
page.  This  you can  do, 1)  by moving  the cursor to the  bottom row  of
asterisks (which, of course, are  not in the text at  all) and then 2)  by
just typing.  (Do you remember the fastest way to get to get to the end of
the page?)

    Incidentally, do not  try to move  the cursor down the page by  simply
typing a  lot of  <cr>'s.  This  forces ETV  to do  a lot  of extra  work,
increases the chance of  error, slows down the  response and loads up  the
system.  There are better ways and besides  it is always better to use  an
argument with any command that will accept one (and many do, besides those
specifically mentioned) than to  type the command as  many times as it  is
wanted.

    !!  So type something at the end of this page, limiting your typing to
a few words without a <cr>.  (First type <form> to get to the next window)

    You will observe that the asterisks  disappear to be replaced by  what
ever you type.

    !!  Now type a  <cr> which will terminate  your line of text  allowing
the asterisks to reappear below your new text.  If you look at the end  of
the header  line  you will  observe  that  the letter  "W"  has  appeared,
indicating that something  has been changed  on the page  that is not  yet
written out.

    !!  Since you may not want  to preserve this, your first attempt,  for
posterity, move the  cursor back to  your line and  type αβD.  Your  newly
typed line is gone beyond recall.

More on the line editor

 !  Incidentally, if you  have been so  careless as to  type αβD when  the
cursor was pointing at a line that was in  the original TEACH text, rather
than at your newly  created line, you  can get the  original text back  by
typing ⊗XCANCEL.  This only works if  you have not saved the altered  page
(as you will  do when you  switch pages), and,  needless to say,  ⊗XCANCEL
will cause all corrections  and additions, that you  may have made to  the
current page (not just to the current windowful), to go away.

    One word of caution,-  The LINE-EDITOR will  only handle lines  having
less than roughly 126 characters.  You will be warned when you reach  this
limit but it is possible to create lines that can't be subsequently edited
without first dividing  them.  Fortunately there  are other commands  that
are not so limited.

    !! Now go to the next page for more.
Simple line-editing commands.

    The line-editor is actually  a part of the  main operating system  and
when you are operating in this mode you are typing directly to the system.
The line editor has a whole set  of commands that you will need to  learn.
In this Teach manual  we will consider only  that subset of commands  that
you will have to know almost at once.

    Certain keys and particularly most normal characters, when typed  with
both the  <control>! and  <meta> keys  depressed,  are  called  activation
characters.  These activation characters terminate the editing of the line
and cause the resulting line to be returned to E.

Six almost essential line-editor commands that you will need to know are:

α<space>   Move the cursor  one character position  to the right  without
	   affecting the text.

<bs>	   Move the cursor by one character position to the left, without
	   affecting the text.  If !the cursor is  1 position beyond  the
	   end of!the text when this command is given, then this  command
	   erases the text as it backs up.

<char>	   Overwrite the character, at the cursor position with the typed
	   character <char>, where <char> can be any normal character.

αD         Delete the character  at the cursor position,  moving the text
	   at the right of the deleted position by one character!position
	   to the left to fill in the missing position. (Note: NOT  αβD.)
	   Note that this command,  if given at the  end of a line,  will
	   add the next line to the end  of the current one, but it  will
	   do this only if the resulting line will contain less than  126
	   characters.

<meta><char>   Insert the character <char> at the cursor position, moving
	   the rest of the text over one character position to make room.

<cr>       Finish editing the line and return control to E, that is, back
	   to the normal  mode with  the cursor moved to  the next  line.
	   (Note: <cr> behaves differently if you are in the LINE-INSERT
	   or INSERT modes, soon to be described.)

    Remember that the line corrections do not appear in the core image and
E has no knowledge of your line-editor corrections until you have typed an
activation character, (of which the <cr> is the most common).

    Furthermore, a corrected page  is not  transfered to  the disk  record
until you have switched  pages, or have issued  a specific request for the
page to be saved.  This has one nice side effect in that if you have  made
a grevious mistake in editing  a page you can  undo your errors by  simply
replacing the present core copy by the one that is still on the disk.

    As noted earlier,the command to undo a page of unwanted corrections is
αXCANCEL<cr> , where the "X" is typed with the <control> key whle the word
CANCEL and the <cr> are typed without control keys.

    The command to write out  a page is α. ,  that is, the  character  "."
(period) is  typed  with  the! control  key  depressed.  This  command  is
unnecessary if you are switching to another page (or another file) but  it
is wise to use this command if you  ar stopping to do something for a  few
minutes or if you are going to try some global!command that might mess  up
your page should you make a mistake.

    !!  To see how this all  works, try editing this paragraph, doing  all
sorts of things to it and when  you have messed it up most horribly,  then
try the ⊗XCANCEL command.  The ⊗XCANCEL command may take a little time  to
function (since it involves a disk reference) so do not be impatient.

More editing commands.  Insertions and deletions.  αβ<CR>  αI  α<cr>  αβD

INSERTIONS.

    There are two special modes that  make editing very much easier.   You
will need to know how to enter and how to leave these modes.

1) The LINE-INSERT mode is entered by the command αβ<cr> .

    Typing the  command αβ<cr>  causes E  to enter  a special  LINE-INSERT
mode, signalled to the user by the appearance of a new blank line in front
of the line to which the cursor had been pointing,  or, if the command  is
given when one is already in the LINE-EDITOR mode, the line will be  split
at the cursor position and the!new blank line!will!appear between the  two
segments of the the former CURRENT line.

    When E is  in this mode,  everything that you  type (again except  for
certain activation characters) will  simply be inserted  into the text  at
the position marked by the cursor.   Carriage returns will be accepted  as
such and you can type as much as you want, for all the world as if you you
were typing on a typewriter, with the added convience that the rest of the
text is always moved down to make room.  Most of the LINE-EDITOR  commands
are available  to  you  and  you  may move  the  cursor  around  and  make
corrections to the line that you are typing as desired.

    To leave the LINE-INSERT mode, you  must type one of several  possible
commands, the!simplest one being α<cr> . This causes you to leave the mode
with the cursor pointing to the last line of your insertion.  The  command
<alt> can also be used  to leave this mode,  but it does different  things
depending upon the  exact situation  at the time  that it  is given.   You
might experiment with this a bit.

2) The INSERT mode is an even simplier affair.

    This is entered from the LINE-EDIT mode by the command αI .

    Typing αI when in the LINE-EDIT  mode causes everything that you  type
thereafter  until  the  next  line-edit  command  to  be  accepted  as  an
insertion, just as would otherwise  be the case if  you were to hold  down
the <meta> key while you were typing.  You may not find this special  mode
to be of  much value, but  you need to  know of its  existance as you  may
enter it by accident and you will need to know what to do if this happens.
To leave this  mode and still  stay in  the LINE-EDIT mode,  one can,  for
example, type α<space> or α<bs>.  The command α<cr> is useful for  leaving
this special mode AND the LINE-EDITOR at the same time.

DELETIONS.

    It is almost as important to be  able to delete text as to create  it,
as you will  find when you  misinterpret these instructions  and make  bad
mistakes.

    The command αβD ,if given while in the normal mode, causes the line at
the cursor to be deleted. This command can take an argument specifying the
number of lines that are to be deleted, starting with the current one, but
take care, this is a very powerful command and you can easily delete  more
than you intend.

PAGING. Introducing and deleting PAGE MARKS.  EXTEND commands.

    Having added some text  to a file  you will want to  break it up  into
pages, and then occasionally you will want to combine two pages into one.

    It is good practice to limit the size of each page to something of the
order of 150 lines  and to start  each page with a  comment or title  line
that defines the material  on the page.  As  mentioned earlier, E keeps  a
directory, usually  on page  1,  which contains  the  first lines  of  all
subsequent pages,  and this  directory may  be used  by you  directly  and
through some search  commands, to  be described  later, to  help you  find
things that you may want to refer to in the file.

    The commands to  do these things  are similar to the ⊗XCANCEL  command
that you learned earlier in that they  begin with the letter X typed  with
control keys.  These are called EXTEND commands, so let's take time out to
learn something about these commands.

EXTEND commands.

    Since there are many more commands in E than there are letters, it  is
necessary to have some multi-letter commands.  Such commands are signalled
by the letter "X" which is typed with one or both of the control keys  and
then followed immediately with  the letters that make  up the name,  typed
without control keys.  There is a further complication , however, in  that
the name may be  shortened as long  as it does  not become ambiguous,  and
certain EXTEND commands may take arguments that follow the name and  these
must be separated from the name by a delimiter.

Two simple EXTEND commands that apply to paging are:

αXM<cr>      The command  to introduce a  page mark is  αXMARK<cr>.   This
	command is given with the cursor  pointing to the line that is  to
	be the first line on the new page.
	(This can be shortened as shown but cannot be shortened to MA !)

αXDEL<cr>    The command to join two pages, that is to DELETE a page-mark,
	is  αXDELETE<cr>,  which can be shortened  as shown.  This command
	is given when the first  of the two pages  (or a portion of it) is
	being viewed. The cursor  need not be at any  particular place  on
	the page.

File switching commands.  α?  αH  αε αλ and α∃   File switches.

(Don't get confused by all the Greek  letters!  Remember that α and β  are
always used in this document to mean <control> and <meta>, but the  others
are really to be typed: αλ means "CONTROL-λ" (EDIT-CTRL-H).  That's the  H
key while holding down both EDIT and CTRL.)

    One of  the first  things that  you will  want to  do after  you  have
mastered the basic  elements of  editing will be  to switch  from file  to
file, both to read or edit another file and later to copy information from
one file into another.  E has some  special commands to make this easy  to
do.

    Perhaps the very first file you will need to reference is the expanded
version of the E manual that is  always available on the system.  The  two
commands that you will need for this purpose are α?  and αH.

α?      This command switches  you to a  special file E.ALS[UP,DOC].   The
	first time that you give this command you will find that page 2 of
	this file is displayed.  Page 2  lists information as to the  most
	recent modifications to  the editor  E.  You  can, however  switch
	from page  to  page, using  all  of  the page  and  window  moving
	commands as required, perhaps going to the directory page (page 1)
	to find  out the  number of  the  page that  concerns you  at  the
	moment.  After you  have once referenced  this file on  subsequent
	references (during any one editing  session) you will be  returned
	to that page and line where you were when you left this file.

    Incidentally, this method of  referencing the E  manual causes you  to
enter the file in what is called the READONLY mode.  You will find that  E
will not  let  you  change the  disk  copy  of this  file,  at  least  not
unintentionally.  Should you try to do this, E will ask you to confirm the
desired mode.  You  must then type  either READONLY  if it was  all a  big
mistake, or READWRITE, if you really want the changes to be made.

    Please do not change the E manual.   If you find a mistake in it,  let
ALS know.  Note that the α? command does not create a separate copy of the
E manual as  the command  HELP ETEACH  did for  the TEACH  file.  You  are
referencing the system copy of this file which others will also use.

αH      This command returns you to the last file that you were using.  So
	if you give this command while looking at the manual you will  get
	back to your former position  in your (H for HOME) file.  (The  α?
	file is never considered to be the HOME file, however).

    !!  By way of practice, try switching to the α? file,  locate the page
that first mentions αH,  and then return here using the αH  command.   You
will later learn a much simplier way to find the desired page in a file by
using the FIND command described on  page 14.  Hint, look at the  diectory
or at page 3.

Switching to other files.

    It is also very easy to switch to  any other file by using one of  two
commands.  One simply types <control>ε , that is the Greek letter  epsilon
typed with the two control keys, followed by the name of the file  desired
and a <cr>.  This  opens the designated file  in the so-called  READ-WRITE
mode, so that you can edit the new file if you so desire.

    Should you wish only to reference this file, (and not to edit it)  you
can use the Greek letter lambda (λ  for look) instead of the Greek  letter
epsilon (ε for enter) and the file  will be opened in READ-ONLY mode.   It
is good practice to always use λ instead of ε whenever this is  sufficient
and E will keep you from unwittingly damaging a file.

αεFOO<cr>   Switch to file FOO (assuming that you have previously creaated
	such a file) so that it is available for editing.

αλFOO<cr>   Switch to file FOO in the readonly mode.

    Certain switches  may  be used  with  these file  switching  commands.
These are single  letters, either with  an argument or  without, that  are
typed after the file name and before the terminating <cr>.  The fact  that
they are switches is signalled by starting  them with a slash (/), and  by
typing them without control bits.  The more useful of these are:

/C	Create a new file with this name.
/26P	Open the file at the start of page 26.
/34E	Open the file at the end of page 34.
/E	Open the file at the end of its last page.
/4P/45L Open the file with the cursor pointing at line 45 on page 4.

    Note that these same switches may be  used with the ET command to  the
system when entering E at  the start of an  editing session.  See page  22
for a more complete list of available switches.

    Once you have entered a file, (during any one editing session) E keeps
a record of the  file name and  your position in this  file and assigns  a
serial number to this information.  You need then only type this number as
a preceding  argument to either  αε or αλ ,without then being required  to
retype the name  of the  file.  You  must observe  the difference  between
these commands as  typed without an  argument, in which  case a  following
file name  must be  typed  terminated by  a <cr>  and  the case  where  an
argument is used  in which case the symbol αε or αλ is the  command and in
which a file  name and  the terminating  <cr> are  not to  be typed.   (As
always, the argument must be typed with control bits).

    Actually E only keeps such records on  the last 8 files that you  have
referenced, but this is usually enough for any one editing session.

α∃      As a mnemonic  aid,  E will  show you the  numbers that have  been
	assigned and the corresponding file names.  To see this, type  the
	command α∃ ,  that is the symbol ∃ (for "there exists") typed with
	the control key.  The desired information will appear on the lines
	at the bottom of the screen.   For your last referenced file,  the
	serial  number in the  listing will be  replaced by  the letter  H
	to show you that you need only type αH to go back to it.

Line marking. αβM and αM

    E provides the facility for marking up to 23 line locations in any one
file with a rapid way to return to these locations by using the  following
commands.  These marks are  preserved with file  switching during any  one
session and they  are still  available when  one returns  to a  previously
marked file.  They are also sticky with  respect to the text so that  they
still reference the specific  text line  to which they were assigned  even
when the line  numbers are changed  by the addition  or deletion of  other
lines ahead  of the  marked lines.   When  a marked  line is  deleted  its
assigned mark disappears.

αβM             Mark the cursor line, that is, record the page number  and
		line number for the CURRENT cursor location,

⊗-αβM           Clear the MARK, if any, for the CURRENT cursor location.

⊗XZMARKS<cr>    Clear all marks in the file that is being edited.

αM              Go to the next MARK (cyclicly).

α2αM            Go the the second Mark from here.

αβ-αM           Go backward one mark (cyclicaly).

    !!  This might be a good time to review, so go back to page 2 and skim
through the file putting marks on those lines that you especially want  to
remember.  When you  have done  this, then go  through the  file again  by
using αM's to switch from  one marked line to  another.  If you feel  that
you would like to know more about  some aspect you might try switching  to
the E.ALS[UP,DOC]  file by  typing α?  to see  what it  the more  complete
manual has to say.   When you switch  back, by using  the αH command,  you
will find that your marks are still available.
ATTACH and COPY.

    The ATTACH and COPY commands permit blocks of lines or copies of  them
to be moved up and down  on the page, from page  to page and from file  to
file as desired.

    The user  is  reminded  of  the existance  of  an  attachment  by  the
fact that the attached lines are shown in bold (extra bright) display.  If
the attachment contains 8 or fewer lines they all show, otherwise only the
first 4 and  the last 3  lines are shown,  separated by a  dotted line  to
signal some  omissions  from the  screen  (but  of course,  not  from  the
attachment).

    On the Datamedia display, the same method (bold characters) is used to
indicate both a line being  edited by the system  line editor, and one  or
more lines which have  been attached.  If more  than one line is  attached
there is no chance of confusion, but if you see a single bold line on  the
screen, remember that if  the blinking cursor is  on that line it's  being
edited by the line editor; if the blinking cursor is down near the  bottom
of the screen, the bold line has been attached.  (When in attach mode  the
cursor will not be inside the text window.)

    Once an attachment has been effected,  it can be moved arround on  the
page, from page to  page and from  file by all of  the usual commands  for
moving the normal cursor.  When a final resting place has been located the
command αβE causes the attachment to be released.  You will find the  MARK
commands useful  for marking places to which you want to move text, before
you have  attached  the  desired lines.   In  this  way you  can  get  the
attachment moved to the  the desired location with  the minimum of  effort
and in the shortest possible  time.  You can mark  lines that you want  to
move but when marked lines are attached their marks are deleted.

Basic commands.

  ⊗A     ATTACH the CURRENT line.
	 Note that the line has been assigned to a special attach buffer
	 although it is still shown on the screen in its original location.

  ⊗3⊗A   ATTACH 3 lines starting with CURRENT.

  ⊗C     COPY the CURRENT line, and attach the copy.
	 Note that in this case a copy has been made and the old line is 
	 still in its original place.

  ⊗4⊗C   COPY 4 lines starting with CURRENT, and attach the copy.

  ⊗E     Deposit the attached lines where displayed and Exit ATTACH mode.
	 Note:   this command has a different meaning when one is NOT in
	 the ATTACH mode (it then means EXIT from E). Don't stutter when
	 typing it. Give the system time to react.

  αβK    KILL the attached lines (they go away beyond recall) and exit
	 from the ATTACH mode. Note that αK does not work (for safety).

    Relative arguments may also be used to add or subtract lines from  the
end of an attachment.  See αβ? for more details.

    A word of warning, a hazard is  involved in moving lines from page  to
page, and from file to  file as the attachment can  be lost if the  system
should crash during the interval between  the attachment of the lines  and
the final updating of the page to  which they are moved.  This hazard  can
be avoided by copying the lines rather than attaching them and then  going
back and deleting the original copy.  This precaution is hardly  necessary
for a few lines of text and, of  course, it is unnecessary if the text  is
being only moved around on the same page.

    This is a good place to comment  on the RIPPLING report, that you  may
notice  in the scratch-pad lines at the bottom of the screen. This  notice
appears when a  major rearrangement  of the text  between records  becomes
necessary.

FIND commands. Single page, multipage and directory searches.

    E provides facilities for searching for desired strings of characters,
either delimited,  that is  as separate  words, or  undelimited.  We  will
explain only the simplest form of  such searches in this manual.  As  soon
as you have mastered these, you may want to refer to ⊗?  to get the entire
story.

Single page searches.

    Single page FIND commands start searching at the CURRENT line, that is
at the line marked by the cursor, and search forward toward the end of the
page.  When the desired string has been found, the cursor is moved to line
in question.   If  the searched-for-string  is  not found,  this  fact  is
reported and the cursor is left in its original position.

    The command αβFSmith<cr> searches for  the word "smith", that is,  for
this as a separate word, whether it is spelled with an initial capital  or
without, (but it nust be separated from the rest of the text by the  usual
word delimiters, spaces, tabs, punctuation marks etc.).

    Note that no space is used between the F and the start of the  string,
and that both  the control and  the meta keys  ARE used with  the "F"  but
that control keys ARE NOT used with the characters of the string  nor with
the <cr>.

    If you want  to find  "smith" even  should it be  a part  of a  longer
sequence of letters, then you type αFsmith<cr> , that is you use only  the
control key <control> with the letter "F".

    One further complication:  Using a simple  carriage return, to  signal
the end of the searched-for-string, leaves the cursor at the beginning  of
the line in which  the string is  found.  Often times  it is desirable  to
have the beginning  of the found  string marked as  well, particularly  if
there are more than one occurance  of the searched-for-string in a  single
line.  To effect this, one merely used the control key <control> with  the
carriage return.

Repeat searches.

    Having found the first  example of some desired  string, you can  find
the next example of  this same string  by the command αβ*  , that is,  the
symbol "*" typed with both control and meta keys.  Note that this  command
simply repeats your previous find  request, whether delimited or not,  and
that the  control  keys used  with  the repeat  command  do not  have  the
significance that  they  did  for the  original  command.   Caution,  this
command always repeats the  last search command given,  whether it be  the
the single page search that has  been described or a multi-page search  as
will be described below.


αβFtheα<cr>    then  will find the next occurance  of the word "the" and
this will be signalled by the  cursor being left under the first  letter
of this word.

   Similarly using only the <control>  key with the repeat command, that
is,  typing <control>*  will  leave the  cursor under  the start  of the
string for repeat searches.

!!     Before going on it might be wise to practice these commands a few
times.

   !!  Move  the cursor to the top of the  page and then search  for the
word "the".  Do  this several times both leaving the cursor at the start
of the line and leaving it under  the first letter of the string.   Note
that  one can  switch between  α* and  αβ* with  the wanted  results for
repeated FINDs.


Multi-page searches.

   Multipage searches are a bit more complicated in that you have to use
an EXTEND command.

   At the present time there is  but one command beginning with  the
   letter "F" so only the "F" needs to  be typed.  Never-the-less we
   must separate this letter from the string that follows by a space
   to prevent the string from being  taken as a part of the  command
   name.

The multipage search commands then are of the form:

αβXF Smith<cr>  Find a  delimited string "smith".
αXF Smith<cr>  Find the string regardless of surroundings.

   Note that CONTROL and  META keys are not used  with the F and  that a
space is required between the F and the string which is typed without
control keys.

   As before one  may use the <control> key  with the <cr> to  cause the
cursor to be positioned under the first character of the found string.

   The command  ⊗* repeats the  last find request,  be it a  single page
search  or a  multi-page search.

   Multi-page searches may take some time for large files.  You are kept
informed as  to the progress of  the search by a  running display of the
number of the page that  is being searched, This information appears  to
the right on the header line.

   You may  interrupt a multi-page  search at  any time by  typing <esc>
followed by  the letter "I".  The search will continue to the end of the
page it is on and then terminate.

   Datamedia users: Remember, <esc> is the NUL key!  The ESC key is <alt>.

Directory searches.

   One final  form of search  is so useful  that it should  be described
here.  This command makes a search on the directory page (which contains
the first lines from all pages in the file) but then the referenced page
is displayed and the cursor is  positioned either at the first occurance
of the searched-for-string (which, of course, will be on the first line)
or at the second occurance of  this string.  One need not be  looking at
the directory to give this command.

The proper final character for these two forms of directory search are:

αP   Make the search over the directory page and then display
     the referenced page with the line pointer at the top line.

αβP  Make the search over the directory page and then display
     the referenced page with the line pointer at the second
     occurance of the referenced string (the first will be in
     the first line of the page).

Finding the Nth occurance.

The search can be for the first  occurance of the specified string
or for the n'th occurance.

   ⊗3⊗Fsmith<cr> Finds the 3rd occurance of SMITH.

If one only wants to know how many examples of the searched-for-string
there are in the document then one asks for an impossibly large number
and the search will be terminated without finding  the specified
occurance.  However, and this is cute, E obligingly reports the number
that it did find.  The symbol "∞" (here meaning 262142) may be used.

    !!  Find how many times the word "the" is used on this page.

Substitution commands.

   One frquently wishes to find all of the  occurances of some string in
order  to change them to  something else, perhaps you  have misspelled a
name or you wish to rename some variable used in a program.

   Substitution commands begin as any normal  search command except that
one  uses, as  a special  termination  for the  searched-for-string, the
symbol "\" , that is a  backslash which must be typed with both  control
keys  thus  <control><meta>\   and  then  one  follows   this  with  the
substitution string terminated by either a <cr> or a <control><cr> .

   The usual  conventions apply  to  the searched-for-string,  that  is,
capitalization is ignored but  the substitution string is made  with due
attention to  the case of the letters.   The searched-for-string itself,
(and not its  delimiters if  it is  a delimited search)  is removed  and
replaced by the substitution string,  which, of course, need not contain
the same number of characters.

   A  substitution may be made  for the first occurance  only or for any
specified number.  A repeat command is available and it is good practice
to always make a single substitution first just to make sure that one is
making the desired substitution  and then to use  the repeat command  to
make the rest of the desired substitutions.

   The repeat command is <control><meta>\ .  This can be preceeded by an
argument (typed with  control keys) and the symbol "∞" (infinity) may be
used.  The αβ\ acts  as the command and no  further delimiter is used.

Text justification. ⊗XJUST,⊗XJFILL ⊗XSJFILL and ⊗XJGET
	(These are EXTEND commands, see p. 10.)

    The margin justifying command ⊗XJFILL  adjusts the lengths of  textual
lines by moving words from line to line as required to achieve any desired
maximum line length.  At the same time this command fixes the left  margin
at any  desired position  (both  for crown  lines,  i.e.  first  lines  of
paragraphs, and for normal text lines), and it either puts the same number
of blank  lines  at  each paragraph  break  as  in the  original  text  or
introduces any desired  number of  blank lines.  The  ⊗XJUST command  also
pads the line  by distributing additional  spaces between words  so as  to
align the right margin as well.

    The range  of  application of  these  commands  may be  limited  by  a
prefixed decimal argument.  If no argument is specified the entire page is
justified.  If  there is  an  attachment the  ATTACH buffer  is  justified
rather than the page.   When the range is  limited by a positive  argument
the justification starts with the cursor line, but for a negative argument
the justification will be  for the specified number  of lines before  (but
not including) the cursor line.

    ⊗XJFILL or ⊗XJUST, preceded by a  0 argument, causes ETV to report  on
the current status of the switch  setting (se below) and of the  resulting
margins without any overt action other than to record any typed changes to
these values (these changes are recorded before the report is made).

    !!  Type α0αXJF<cr> to verify this, and then read the next paragraph.

    The last  4 numbers  that are  reported, refer,  respectively, to  the
crown line  indent, the  non-crown-line  indent, the  rightmost  character
position and  to the  number of  blank lines  that are  to appear  between
paragraphs.  When a negative number is shown, it means,  by
convention, that there is  to be the same  distribution of blank lines  in
the output text as in the input  text.  By following your commands with  a
string of  numbers, separated  by commas,  as shown,  you can  change  the
default values to anything that you desire.  These values are sticky, that
is, once changed they stay changed (until changed again) and they need not
be retyped with subsequent commands.  There are no limits as to the values
that may be assigned to the left indents or to the right margin value,  so
it is possible to create lines that cannot be edited with the LINE-EDITOR.

	The full explanation of these commands is beyond the scope of this
TEACH manual.  See ⊗?  for details.

EXAMPLES for beginners and for casual users.

    As a beginner  you might like  to use these  commands without  getting
into all of  the gory  details.

*** If you are willing to use the initial default conditions.

    Type ⊗6⊗XJF<cr> to effect the  left-justification of 6 lines  starting
with the  cursor line or  ⊗Xju<cr>  if you  want  the entire  page  to  be
justified and padded to preserve the right margin as well.

	Under these conditions E uses the presence of a blank line  or
    of a line  that is indented  by 2 or  more character positions  to
    signal the start of a new  paragraph and it expects all  non-crown
    lines to be indented by less  than 2 character positions.  In  the
    output text,  crown  lines (first  lines  of all  paragraph)  will
    follow the same number of blank lines as were in the original taxt
    and they will  be indented  by 4  character positions.   Non-crown
    lines will all start at the left margin and the maximum number  of
    characters on a line will be 74.

*** If you want the new crown indents to be 8 (actually a TAB) and are
    willing to use the other default values.

    Type ⊗9⊗9⊗XJU 8<cr> only.

*** If you prefer to have new paragraphs signalled by blank lines only and
    want the indentations in the original text to be completely ignored.

    Type ⊗6⊗XJF A<cr> or ⊗7⊗XJU A<cr> as the case may be.

	This sets a special A (for  Assigned) switch which tells E  to
    use some assigned  input indent conditions  for which the  default
    values are initially set at 0,0  which causes E to behave as  just
    noted.

There are several other commands that you might like to use.

⊗XSJF<cr>

    The command ⊗XSJF<cr> causes all  sentences in the designated text  to
be separated into individual sentences.   This makes it easy to  rearrange
sentences within a document.   Caution, this command obliterates all crown
indents so it is well to have  blank lines between paragraphs in order  to
preserve paragraph  breaks.   Having  rearanged  the  sentences  to  one's
satisfaction, they  can then  be put  back togather  with a  ⊗XJF or  ⊗XJU
command.  The decision as to what is a sentence is made on the basis of  a
sentence-ending punctuation mark that is followed by either 2 spaces or  a
carriage return.  Some funny things will happen if such marks are used  in
the text, in mathematical equations or the like, so be careful.

    !!  Try this command  on this page,  but only if  you are prepared  to
undo its effect with a ⊗XCANCEL command.

⊗XJGET<cr>

    The ⊗XJGET<cr>  command  allows one  to  have E  examine  a  specified
portion of text to determine the indents and right margin that were  used.
This is of use, primarily,  with text that is  quite abnormal as to  these
properties, for example,  if the  lines are  too long  to be  seen on  the
screen or  even  too  long to  edited  (since  there is  a  limit  of  126
characters that applies to the LINE-EDITOR  and there is no limit for  the
justification commands).

    !!  You  might like  to experiment  with this  command since  it  does
nothing to your  text.  You will observe  that you  get different  answers
depending upon  the location  of the  cursor and upon  the extent  of  the
designated text.

    There is a complete set of additional commands, similar to those  that
have been described, that are designed for use with tabular material.   As
an example, the tabular lists of commands with there explanations that you
have seen in TEACH  (the next page  is a good  example) were justified  by
using these commands.  See ⊗? for details.

Margin fixing commands. ⊗XALIGN<cr> ⊗XCENTER<cr> ⊗XINDENT<cr> ⊗→ and ⊗←
		(3 EXTEND commands and 2 that are not.)

    These commands are related to the justification commands in that  they
adjust margins but the text is not shuffled between lines.  These commands
take a  prefixed argument  specifying  the number  lines  that are  to  be
processed, but the default is one line, rather than the entire page as  it
was for the justification commands.  Negative, zero and positive  prefixed
arguments may be used.

Some examples follow:

⊗XALIGN<cr>     Align at the cursor line, with the left margin indent  set
		at the default value, which initially is 0.

⊗8⊗XALIGN 4<cr>  Align 8 lines starting  at the cursor line with the  left
		margin indent set  at 4 and  change the default  alignment
		value to 4.

⊗XCENTER<cr>    Center the cursor line between the margins that have  been
		set for or by a previously executed justification command.

⊗XINDENT<cr>    Indent the cursor line by the default  value which is  set
		initially at 4, that  is move the text  to the right by  4
		character positions.  If  the resulting total  indentation
		is 8  or more  spaces, TABs  will be  used to  the  extent
		possible.

⊗5⊗XINDENT -3<cr>  Change the  default indent  value to  -3 and  indent  5
		lines by this  amount, that is,  move the 5  lines to  the
		left by 3 character positions  (but do not shift any  line
		far enough to lose  any non-space characters).  Note  that
		the relative  indentations  of  the  lines  moved  is  not
		changed by an indent command as long as an attempt is  not
		made to shift any line too far to the left.

    The following commands are faster to  use than is the XINDENT command.
The (absolute) default value associated  with the XINDENT command is  used
by these (non-EXTEND) commands.   Less confusion will  result if you  keep
the default INDENT value as a positive number but this is not a requirment
as the following commands take the absolute value in any case.

⊗4⊗→            Shift 4  lines  to  the right  using  the  absolute  value
		associated with the XINDENT command.

⊗6⊗←            Move 6 lines to the left by the absolute value  associated
		with the  XINDENT command  (if  this is  possible  without
		losing any non-space  characters, otherwise stop  shifting
		each line when this limit is reached).
Some other EXTEND commands.

    You have,  by now,  encountered several  EXTEND commands.   There  are
several other EXTEND commands that you  will want to know about very  soon
but you will have to refer to  ⊗? for full details.  For completeness,  we
will review the way that these commands  are written and list some of  the
more useful EXTEND commands.

    Certain commands are potentially too dangerous to be safely evoked  by
a single character. There are also more commands than can be obtained with
single characters.  These contingencies are handled by the EXTEND  command
specified as follows:

⊗X              Accept the string that follows  as a command. This  string
		may be abbreviated as long  as no ambiguity results.   The
		string is  typed  without  control keys  and  it  must  be
		terminated by a space if parameters are required, or by  a
		<cr> or other deliniter.

The more useful EXTEND commands are:

⊗XBREAK<cr>     Break a  long line  into  segments as  defined by  a  line
		length that may be  changed but that  is initially set  to
		80.  This command will accept lines of any length and does
		not require  them to  contain cr's.   See ⊗?  page 12  for
		details.  Note  especially that  this command  breaks  the
		line quite  arbitrarily  and  not necessarily  at  a  word
		boundary.


⊗XCANCEL<cr>    Do not write out the current page but instead reread it in
		from the disk.

⊗XCLOSE<cr>     Close the file.  This allows others to read it if you  had
		modified it,  without  interfering with  your  ability  to
		still read it.  You may, however, be prevented from making
		further modifications should  someone else  start to  read
		the file.

⊗XDEFINE<cr>    Define a  macro-command which  can  then be  executed  any
		desired number of times by  a simple (⊗#⊗Y) command.   See
		page 25 in ⊗? for detailes.

⊗XDELETE<cr>    See page 13 for details.

⊗XDRAW<cr>      Redraw the complete screen.  Used when unwanted marks show
		on the screen  from whatever cause.   (This does the  same
		thing as ⊗V).

⊗XFIND<cr>      see page 14 for details on FIND.

⊗XGO<cr>        Exit from E and repeat the last COMPILE-type command.

⊗XJOIN<cr>      Join as many  lines as  specified by  an initial  argument
		into one line,  regardless of its  resulting length.   The
		default argument is 2.  See ⊗? page 12 for details.

⊗XJUST<cr>      See page 19 for details.

⊗XLINCNT<cr>    Report the number of characters  in the current line,  and
		the number of characters on the entire page.

⊗XMAIL<cr>      Send mail to the designated person. See ⊗? for details.

⊗XMARK<cr>      See page 13 for details.

⊗XPAREN<cr>     A  Parenthesis  matching  command.  See  ⊗?  page  22  for
		details.

⊗XPROTECT<cr>   Display or  change  the  PROTECTION  for  the  file  being
		viewed.  See ⊗? page 19 for details.

⊗XQUIT<cr>      Quit (exit) E WITHOUT updating the disk record.

⊗XREADONLY<cr>  Inhibit any  commands  that  will cause  the  file  to  be
		written out  and  ask  for confirmation  of  desired  mode
		before proceeding.

⊗XREADWRITE<cr>  Disable the write-inhibit.

⊗XREMIND<cr>    Send reminder.  See ⊗? for details.

⊗XSEND<cr>      Send message.  See ⊗? for details.

⊗XRSYS PRGM<cr>  Exit and runs SYS:PRGM

⊗XRUN PRGM<cr>  Exit and runs DSK:PRGM

⊗XSPOOL<cr>     Spool the  page that  is being  displayed, or  the  attach
		buffer only if something is attached.

⊗XXSPOOL<cr>    XGP spool the page that is being displayed, or the  attach
		buffer if something is attached.

System commands to evoke E.

   Basic commands

	CETV <string><cr>
		Create a new file with the name and extension as
 		  specified by string.
		  The file will contain a directory page and one
		  blank page.
	ETV <existing file name><cr>
		Enter E with the specified file. If the file has
		  but one text page, display this, otherwise
		  display the directory page.
	ETV	Reenter E with the most recently edited file and
		  display the most recently opened page (subject
		  to certain restrictions as described in the
		  Monitor Manual).	
	ETV <string1>←<string2><cr>
		Copy file named string2 into a new file named
		  string1, start E and display the text as above.
		  If the string2 file has a valid directory this
		  is executed relatively rapidly, if not a new
		  directory will have to be created. (See the note
		  below with respect to the /N switch).

	R E;<string1>←<string2><cr>
		Similar to ETV  <string1>←<string2> except for the
		  way it handles the TMPCOR files. (See the Monitor
		  Manual for this and other RPG features).

   Switches, when used, are strings beginning with a slash which are
placed immediately after the file name that they are to modify.

	/E	Open the file with the cursor pointing to the asterisks
		  on the last page of the file (in the position to add text).
	/6E	Open the file with the cursor pointing to the asterisks
		  at the end of page 6.
	/F	Repage the file as it is being read in, limiting the number
		  of lines on a page to a maximum of 33 (1 windowful).
		  Existing page marks are respected.
	/62F	Repage the file as before but with the maximum number of
		  lines set at 62 instead of the default value of 33.
	/5L	Open the file with the cursor at line 5.
		  This is not very useful by itself but see below.
	/N	No Directory. The inexperienced user is advised to avoid
		  using this switch as there are some commands that cause
		  trouble when used with no-directory files.
	/2P	Open the file displaying page 2.
	/R	Open the file in the read only mode. This is useful
 		  if one wants to examine a file without any danger
		  of inadvertently modifying it.
		    example: ET TEACH[UP,DOC]/R<cr>

   When two or more switches are to be used they may be put together
inside parenthesis.

		example: ET MYFILE(R4P5L)<cr>

Summary.

Remember that you still have not been told all there is to know about E.
It would be a good idea for you to spend some time looking at ⊗? so that
you will know something about the many other commands that are available.

Credits:

    Dan Swinehart wrote TV,  the original version  of the display  editor,
and created the  original version of  TEACH.  Fred Wright  wrote the  FAIL
version of TV  (called E).  This  has been extended  and modified by  many
different people, with major contributions by Arthur Samuel, Brian Harvey,
and Martin Frost.

    Suggestions as to ways to improve this version of TEACH should be sent
to ALS.

    Disclaimer.

    An attempt has been made to present a coordinated view of E.  To  this
end some simplications have  been made. The  experienced user may  develop
techniques that  are not  described in  this manual.  Any outright  errors
should, however, be called to our attention.