Usenet 1994 October/usenetsourcesnewsgroupsinfomagicoctober1994disk2.iso/misc/volume1/8711/15

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From: [e-mail] (Daniel Lawrence)
Newsgroups: comp.sources.misc
Subject: MicroEmacs 3.9 Manual (4 of 6)
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Date: 26 Nov 87 04:16:09 GMT
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X          called  a  destructive  backspace--it  removes  text  immediately
X          before the current cursor position from the buffer.  Now  type ^H
X
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X                                                                          8
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X          Basic Editing--Simple Insertions and Deletions         MicroEMACS
X                                                           Reference Manual
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X          delete-previous-character.  Notice that the cursor moves back and
X          obliterates the "r"--either command will backspace the cursor.
X
X                  Type in the two letters you erased to  restore  your text
X          and move the cursor to the beginning of the buffer M-> beginning-
X          of-file.  Move the cursor down  one  line to the beginning of the
X          first paragraph.
X
X                  To  delete  the  forward  character, type ^D delete-next-
X          character.  The "F" of "Fang" disappears.  Continue  to  type  ^D
X          until the whole word is erased EMACS also permits the deletion of
X          larger elements of text.  Move the cursor to the word "center" in
X          the first line of text.  Pressing  M-<backspace> delete-previous-
X          word kills the word immediately before the cursor.  M-^H  has the
X          same effect.
X
X                  Notice that  the commands are very similar to the control
X          commands you used to  delete  individual  letters.   As a general
X          rule in EMACS, control sequences affect small areas of text, META
X          sequences larger areas.  The  word forward of the cursor position
X          can therefore be deleted by  typing  M-D  delete-next-word.   Now
X          let's take out the remainder of the first line by typing ^K kill-
X          to-end-of-line.  You now have a blank line  at  the  top  of your
X          screen.   Typing ^K again or ^X-^O delete-blank-lines deletes the
X          blank  line  and  flushes the second line to the top of the text.
X          Now exit EMACS by typing ^X-^C exit-emacs .  Notice EMACS reminds
X          you that you have not saved your buffer.  Ignore the  warning and
X          exit.  This  way  you  can  exit  EMACS without saving any of the
X          changes you just made.
X
X
X
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X                                  Chapter 2 Summary
X
X
X                  In Chapter  2,  you  learned  about  the  basic 'building
X          blocks' of an EMACS text file--buffers, windows, and files.
X
X          Key binding             Keystroke       Effect
X          delete-previous-character
X                                  ^H              deletes character immediately
X                                                  before
X                                                  the current cursor position
X
X          delete-next-character   ^D              deletes character immediately after
X                                                  current cursor position
X
X          delete-previous-word    M-^H            deletes word immediately before
X                                                  current cursor position
X
X          delete-next-word        M-D             deletes word immediately after
X                                                  current cursor position
X
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X          9
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X          MicroEMACS Reference Manual  Basic Editing--Simple Insertions and
X                                                                  Deletions
X
X
X          kill-to-end-of-line     ^K              deletes from current cursor
X                                                  position to end of line
X
X          insert-space            ^C              inserts a space to right of cursor
X
X          open-line               ^O              inserts blank line
X
X          delete-blank-lines      ^X-^O           removes blank line
X
X          exit-emacs              ^X-^C           exits emacs
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X                                                                         10
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X          Using Regions                         MicroEMACS Reference Manual
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X                                      Chapter 3
X
X                                    Using Regions
X
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X          3.1  Defining and Deleting a Region
X
X
X                  At this  point its time to familiarize ourselves with two
X          more EMACS terms--the point  and  the mark.  The point is located
X          directly behind the current  cursor  position.    The mark (as we
X          shall see shortly) is user  defined.  These two elements together
X          are called the  current  region  and  limit the region of text on
X          which EMACS performs many of its editing functions.
X
X                  Let's begin by entering some new text.   Don't  forget to
X          add wrap  mode  if  its  not set on this buffer.  Start EMACS and
X          open a file called PUBLISH.TXT.  Type in the following text:
X
X               One of the largest growth areas  in  personal computing
X               is electronic publishing.  There are packages available
X               for practically  every  machine  from  elegantly simple
X               programs  for the humble Commodore 64 to  sophisticated
X               professional packages for PC and Macintosh computers.
X
X               Electronic publishing is as revolutionary in its way as
X               the  Gutenburg  press.    Whereas  the  printing  press
X               allowed  the  mass  production  and distribution of the
X               written  word, electronic publishing puts the means  of
X               production  in  the  hands  of nearly every individual.
X               From  the  class  magazine  to  the  corporate  report,
X               electronic publishing is changing  the  way  we produce
X               and disseminate information.
X
X               Personal  publishing  greatly  increases the utility of
X               practically every computer.   Thousands  of  people who
X               joined the computer revolution of this  decade  only to
X               hide their machines unused in closets have discovered a
X               new use for them as dedicated publishing workstations.
X
X                  Now  let's  do  some editing.  The last paragraph seems a
X          little out of place.  To see what the document looks like without
X          it we can  cut  it  from  the  text  by  moving the cursor to the
X          beginning of the paragraph.   Enter  M-<space>  set-mark.   EMACS
X          will respond with "[Mark set]".   Now  move the cursor to the end
X          of the paragraph.  You have  just  defined  a region of text.  To
X          remove  this  text  from  the  screen, type ^W kill-region.   The
X          paragraph disappears from the screen.
X
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X          11
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X          MicroEMACS Reference Manual                         Using Regions
X
X
X                  On further consideration, however, perhaps  the paragraph
X          we cut wasn't so bad after all.  The problem may have been one of
X          placement.  If  we  could  tack  it  on  to  the end of the first
X          paragraph it might work quite  well to support and strengthen the
X          argument.  Move the cursor to the end of the first  paragraph and
X          enter ^Y yank.  Your text should now look like this:
X
X               One of the largest growth areas  in  personal computing
X               is electronic publishing.  There are packages available
X               for practically  every  machine  from  elegantly simple
X               programs  for the humble Commodore 64 to  sophisticated
X               professional  packages for PC and Macintosh  computers.
X               Personal  publishing  greatly  increases the utility of
X               practically every computer.   Thousands  of  people who
X               joined the computer revolution of this  decade  only to
X               hide their machines unused in closets have discovered a
X               new use for them as dedicated publishing workstations.
X
X               Electronic publishing is as revolutionary in its way as
X               the  Gutenburg  press.    Whereas  the  printing  press
X               allowed  the  mass  production  and distribution of the
X               written  word, electronic publishing puts the means  of
X               production  in  the  hands  of nearly every individual.
X               From  the  class  magazine  to  the  corporate  report,
X               electronic publishing is changing  the  way  we produce
X               and disseminate information.
X
X
X          3.2  Yanking a Region
X
X
X                  The text you cut initially didn't simply  just disappear,
X          it  was  cut  into  a  buffer  that  retains  the  'killed'  text
X          appropriately called the kill buffer.  ^Y "yanks"  the  text back
X          from this buffer into the current buffer. If you have a long line
X          (indicated,  remember,  by  the  "$"  sign),  simply  hit M-Q  to
X          reformat the paragraph.
X
X                  There are other uses to which the kill buffer can be put.
X          Using the method we've already learned, define the last paragraph
X          as  a  region.   Now type M-W copy-region.  Nothing seems to have
X          happened; the cursor stays  blinking  at  the  point.  But things
X          have  changed,  even  though you may  not  be  able  to  see  any
X          alteration.
X
X                  To  see what has happened to the  contents  of  the  kill
X          buffer, move the  cursor  down  a  couple of lines and "yank" the
X          contents  of  the kill buffer back with  ^Y.    Notice  the  last
X          paragraph is now repeated.  The region you defined is "tacked on"
X          to the end of your file because M-W copies a  region  to the kill
X          buffer while leaving the  original  text  in your working buffer.
X          Some caution is needed however,  because the contents of the kill
X          buffer are updated when you delete any regions,  lines  or words.
X          If  you  are  moving  large  quantities  of  text,  complete  the
X
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X                                                                         12
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X          Using Regions                         MicroEMACS Reference Manual
X
X
X          operation before you do any more deletions or you could find that
X          the  text  you  want to move has been replaced by the most recent
X          deletion.  Remember--a buffer is  a  temporary  area  of computer
X          memory that is lost when the machine is powered down  or switched
X          off.  In order to make your changes permanent, they must be saved
X          to  a  file  before you leave EMACS.  Let's delete the section of
X          text we just added and save the file to disk.
X
X
X
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X                                  Chapter 3 Summary
X
X
X                  In  Chapter  3,  you  learned  how   to   achieve  longer
X          insertions  and  deletions.   The EMACS terms point and mark were
X          introduced and you learned how to manipulate text  with  the kill
X          buffer.
X
X          Key Binding     Keystroke       Effect
X
X          Delete-Region   ^W              Deletes region between point and mark and
X                                          places it in KILL buffer
X
X          Copy-Region     M-W             Copies text between point and mark into
X                                          KILL buffer
X
X          Yank-Text       ^Y              Inserts a copy of the KILL buffer into
X                                          current buffer at point
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X          13
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X          MicroEMACS Reference Manual                    Search and Replace
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X                                      Chapter 4
X
X                                 Search and Replace
X
X
X          4.1  Forward Search
X
X
X                  Load EMACS and bring in the file you just  saved.    Your
X          file should look like the one below.
X
X               One of the largest growth areas  in  personal computing
X               is electronic publishing.  There are packages available
X               for practically  every  machine  from  elegantly simple
X               programs  for the humble Commodore 64 to  sophisticated
X               professional  packages for PC and Macintosh  computers.
X               Personal  publishing  greatly  increases the utility of
X               practically every computer.   Thousands  of  people who
X               joined the computer revolution of this  decade  only to
X               hide their machines unused in closets have discovered a
X               new use for them as dedicated publishing workstations.
X
X               Electronic publishing is as revolutionary in its way as
X               the  Gutenburg  press.    Whereas  the  printing  press
X               allowed  the  mass  production  and distribution of the
X               written  word, electronic publishing puts the means  of
X               production  in  the  hands  of nearly every individual.
X               From  the  class  magazine  to  the  corporate  report,
X               electronic publishing is changing  the  way  we produce
X               and disseminate information.
X
X                  Let's use EMACS to search for the word "revolutionary" in
X          the second paragraph.   Because  EMACS  searches from the current
X          cursor  position  toward  the  end  of buffers, and we intend  to
X          search forward, move the  cursor  to  the  beginning of the text.
X          Enter ^S search-forward.  Note that the command line now reads
X
X                  "Search [] <META>:"
X
X                  EMACS is prompting you to  enter the search string -- the
X          text you want to find.  Enter the word revolutionary and  hit the
X          META  key.     The   cursor   moves   to  the  end  of  the  word
X          "revolutionary."
X
X                  Notice  that  you  must enter the <META> key to start the
X          search.  If you simply press <NL> the command line  responds with
X          "<NL>".  Although this may seem infuriating to users who are used
X          to pressing the return key to execute any command, EMACS'  use of
X
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X                                                                         14
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X          Search and Replace                    MicroEMACS Reference Manual
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X          <META>  to  begin  searches allows it to pinpoint text with great
X          accuracy.  After every line wrap or carriage return, EMACS 'sees'
X          a new line character (<NL>).  If you need to search for a word at
X          the end of a line, you can specify this word uniquely in EMACS.
X
X                  In our sample text for example, the word  "and"  occurs a
X          number  of times, but only once at the end of a line.  To  search
X          for this particular occurence of the word, move the cursor to the
X          beginning of the buffer and type ^S.  Notice  that  EMACS  stores
X          the last specified search  string  as the default string.  If you
X          press  <META>  now,  EMACS will search for the default string, in
X          this case, "revolutionary."
X
X                  To change this string so  we can search for our specified
X          "and" simply enter the word and followed by <NL>.    The  command
X          line now shows:
X
X                  "search [and<NL>]<META>:"
X
X                  Press <META> and the cursor moves to "and" at the  end of
X          the second last line.
X
X
X          4.2  Exact Searches
X
X
X                  If the mode EXACT is  active in the current buffer, EMACS
X          searches on a case sensitive basis.  Thus, for example  you could
X          search for Publishing as distinct from publishing.
X
X
X          4.3  Backward Search
X
X
X                  Backward  searching is very similar to forward  searching
X          except  that  it  is  implemented  in the reverse direction.   To
X          implement a reverse  search,  type  ^R  search-reverse.   Because
X          EMACS makes no distinction between  forward  and  backward stored
X          search strings, the last search item you entered  appears  as the
X          default string.   Try  searching  back  for  any  word  that lies
X          between the cursor and the beginning of the buffer.   Notice that
X          when the item is found, the  point  moves to the beginning of the
X          found string (i.e., the cursor  appears under the first letter of
X          the search item).
X
X                  Practice searching for other words in your text.
X
X
X          4.4  Searching and Replacing
X
X
X                  Searching and replacing is  a  powerful  and quick way of
X          making changes to your text.  Our sample text is about electronic
X          publishing, but the correct term  is  'desktop'  publishing.   To
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X          MicroEMACS Reference Manual                    Search and Replace
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X          make the necessary changes we need to replace  all  occurences of
X          the word "electronic"  with  "desktop." First, move the cursor to
X          the top of the current buffer with the M-< command.  Then type M-
X          R replace-string.  The command line responds:
X
X                  "Replace []<META>:"
X
X                  where  the  square  brackets  enclose the default string.
X          Type the word  electronic  and  hit  <META>.    The  command line
X          responds:
X
X                  "with []<META>"
X
X                  type desktop<META>.  EMACS replaces all instances  of the
X          original word with your revision.  Of course, you  will  have  to
X          capitalize the first letter of "desktop" where it  occurs  at the
X          beginning of a sentence.
X
X                  You have just completed  an  unconditional  replace.   In
X          this operation, EMACS replaces every instance of the found string
X          with the replacement string.
X
X
X          4.5  Query-Replace
X
X
X                  You may also replace text on  a  case by case basis.  The
X          M-^R query-replace-string command causes EMACS to  pause  at each
X          instance of the found string.
X
X                  For example,  assume we want to replace some instances of
X          the  word  "desktop"  with  the  word "personal." Go back to  the
X          beginning of  the current buffer and enter the M-^R query-replace
X          command.    The  procedure is very  similar  to  that  which  you
X          followed in the unconditional search/replace  option.    When the
X          search begins however, you will  notice that EMACS pauses at each
X          instance of "publishing" and asks  whether you wish to replace it
X          with the replacement  string.    You  have  a  number  of options
X          available for response:
X
X                  Response        Effect
X                  Y(es)   Make the current replacement and skip to the next
X                          occurence of the search string
X
X                  N(o)    Do not make this replacement but continue
X
X                  !       Do the rest of the replacements with no more queries
X
X                  U(ndo)  Undo just the last replacement and query for it
X                          again (This can only go back ONE time)
X
X                  ^G      Abort the replacement command (This action does not
X                          undo previously-authorized replacements
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X          Search and Replace                    MicroEMACS Reference Manual
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X                  .       Same effect as ^G, but cursor returns to the point at
X                          which the replacement command was given
X
X                  ?       This lists help for the query replacement command
X
X                  Practice searching and  searching and replacing until you
X          feel comfortable with the commands and their effects.
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X                                  Chapter 4 Summary
X
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X                  In this  chapter, you learned how to search for specified
X          strings of text in EMACS.  The chapter also dealt  with searching
X          for and replacing elements within a buffer.
X
X          Key Binding             Keystroke                        Effect
X
X          Search-Forward          ^S      Searches from point to end of buffer.
X                                          Point is moved from current location to
X                                          the end of the found string
X
X          Search-Backward         ^R      Searches from point to beginning of buffer.
X                                          Point is moved from current location to
X                                          beginning of found string
X
X          Replace                 M-R Replace ALL ocurrences of search string with
X                                          specified (null) string from point to the
X                                          end of the current buffer
X
X          Query-Replace          M-^R     As above, but pause at each found string
X                                          and query for action
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X          17
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X          MicroEMACS Reference Manual                               Windows
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X                                      Chapter 5
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X                                       Windows
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X          5.1  Creating Windows
X
X
X                  We  have  already  met windows in an earlier chapter.  In
X          this  chapter,  we  will  explore  one  of  EMACS' more  powerful
X          features   --  text  manipulation  through  multiple   windowing.
X          Windows  offer  you  a powerful and easy way to edit  text.    By
X          manipulating  a  number  of  windows  and buffers on  the  screen
X          simultaneously, you can perform complete edits  and  revisions on
X          the computer screen while having your draft text or original data
X          available for reference in another window.
X
X                  You will recall that windows  are  areas  of  buffer text
X          that  you  can see on the screen.    Because  EMACS  can  support
X          several screen windows simultaneously  you  can  use them to look
X          into different places in the same buffer.  You can also  use them
X          to  look  at  text in different buffers.  In effect, you can edit
X          several files at the same time.
X
X                  Let's  invoke EMACS and pull back  our  file  on  desktop
X          publishing by typing
X
X               emacs publish.txt
X
X                  When  the  text   appears,  type  the  ^X-2  split-window
X          command.  The window  splits  into two windows.  The window where
X          the cursor resides is  called  the current window -- in this case
X          the bottom window.  Notice that each window has a text area and a
X          mode line.  The command line is however, common to all windows on
X          the screen.
X
X                  The two  windows  on  your  screen  are  virtually mirror
X          images of each other because the new window is  opened  into  the
X          same buffer as the one you are in when you issue  the open-window
X          command.  All  commands  issued  to  EMACS  are  executed  on the
X          current buffer in the current window.
X
X                  To move the cursor  to  the  upper  window (i.e., to make
X          that  window  the  current  window,  type  ^X-P  previous-window.
X          Notice  the  cursor  moves  to  the  upper  or  previous  window.
X          Entering ^X-O next-window moves to  the  next  window.   Practice
X          moving between windows.   You  will notice that you can also move
X          into the Function Key menu by entering these commands.
X
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X                                                                         18
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X          Windows                               MicroEMACS Reference Manual
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X
X                  Now move to the upper window.  Let's open a new file.  On
X          the  EMACS disk is a tutorial file.  Let's call it into the upper
X          window by typing:
X
X               ^X-^F
X
X                  and press return.
X
X                  Enter the filename emacs.tut.
X
X                  In a short time,  the  tutorial  file  will appear in the
X          window.  We now have two windows on the screen, each looking into
X          different buffers.  We have just used the ^X-^F find-file command
X          to find a file and bring it into our current window.
X
X                  You can scroll any  window  up  and  down with the cursor
X          keys, or with the commands we've learned so far. However, because
X          the area of visible text in each window is relatively  small, you
X          can scroll the current window a line at a time.
X
X                  Type ^X-^N move-window-down
X
X                  The  current  window  scrolls down by one line -- the top
X          line of  text  scrolls  out  of  view,  and the bottom line moves
X          towards the top of the screen.  You can imagine, if you like, the
X          whole window  slowly  moving  down  to  the  end of the buffer in
X          increments of one line.  The command ^X-^P move-window-up scrolls
X          the window in the opposite direction.
X
X                  As we have  seen,  EMACS editing commands are executed in
X          the current window, but the program does support a useful feature
X          that allows you to scroll the next window.    M-^Z scroll-next-up
X          scrolls the next  window  up,  M-^V  scroll-next-down  scrolls it
X          downward.   From  the  tutorial  window,  practice  scrolling the
X          window with the desktop publishing text in it up and down.
X
X                  When you're  finished,  exit  EMACS  without  saving  any
X          changes in your files.
X
X
X                  Experiment  with  splitting  the  windows on your screen.
X          Open windows into different buffers and experiment with any other
X          files you may have.  Try editing the  text  in  each  window, but
X          don't  forget  to  save any changes you want to keep -- you still
X          have to save each buffer separately.
X
X
X          5.2  Deleting Windows
X
X
X          Windows allow you to perform  complex  editing  tasks  with ease.
X          However,  they  become  an  inconvenience  when  your  screen  is
X          cluttered  with  open  windows  you  have  finished  using.   The
X          simplest solution is to delete  unneeded  windows.    The command
X
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X          19
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X          MicroEMACS Reference Manual                               Windows
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X          ^X-0 delete-window  will  delete  the  window  you  are currently
X          working in and move you to the next window.
X
X                  If you have a number of windows open, you can  delete all
X          but the current window by entering ^X-1 delete-other-windows.
X
X
X          5.3  Resizing Windows
X
X
X                  During complex editing tasks, you will  probably  find it
X          convenient  to  have  a  number   of   windows   on   the  screen
X          simultaneously.       However   this   situation   may    present
X          inconveniences because the more  windows  you  have on the screen
X          the smaller they are; in some cases, a  window  may  show  only a
X          couple of lines of text.  To increase the flexibility and utility
X          of the window environment, EMACS  allows you to resize the window
X          you  are  working  in  (called,  as you will recall, the  current
X          window) to a convenient size  for easier editing, and then shrink
X          it when you no longer need it to be so large.
X
X                  Let's try an example.  Load in any EMACS  text  file  and
X          split the current window into two.  Now type ^X-^(Shift-6), grow-
X          window.   Your  current  window  should  be  the lower one on the
X          screen.  Notice that it increases in size upwards  by  one  line.
X          If  you  are  in  the  upper  window,  it increases in size in  a
X          downward   direction.      The   command   ^X-^Z,   shrink-window
X          correspondingly decreases window size by one line at a time.
X
X                  EMACS also allows  you  to resize a window more precisely
X          by entering a numeric argument  specifying the size of the window
X          in  lines.  To resize the window this way, press the META key and
X          enter  a  numeric  argument (remember to keep it smaller than the
X          number of lines on your screen display) then  press  ^X-W resize-
X          window.  The  current  window  will  be enlarged or shrunk to the
X          number of lines specified in the numeric argument.    For example
X          entering:
X
X               M-8 ^X-W
X
X          will resize the current window to 8 lines.
X
X
X          5.4  Repositioning within a Window
X
X
X                  The cursor may be  centered  within  a window by entering
X          M-! or M-^L redraw-display.  This command is especially useful in
X          allowing  you  to  quickly  locate  the cursor if you are  moving
X          frequently from window to window.  You can also use  this command
X          to move the line containing the cursor to any position within the
X          current window.  This is done by using a numeric  argument before
X          the command. Type M-<n> M-^L where <n> is the number of  the line
X          within the window that you wish the current line to be displayed.
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X          MicroEMACS Reference Manual                               Windows
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X                  The ^L Refresh-screen command is useful for 'cleaning up'
X          a 'messy' screen that can result of using EMACS  on  a  mainframe
X          system and being interupted by a system message.
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X          Windows                               MicroEMACS Reference Manual
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X          Chapter 5 summary
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X                  In Chapter 5 you  learned  how  to manipulate windows and
X          the editing flexibility they offer.
X
X          Key Binding     Keystroke       Effect
X
X          Open-Window     ^X-2            Splits current window into two windows if
X                                          space available
X
X          Close-Windows   ^X-1            Closes all windows except current window
X
X          Next-Window     ^X-O[oh]        Moves point into next (i.e. downward)
X                                          window
X
X          Previous-Window ^XP             Moves point to previous (i.e. upward)
X                                          window
X
X          Move-Window-Down ^X-^N          Scrolls current window down one line
X
X          Move-Window-Up  ^X-^P           Scrolls current window up one line
X
X          Redraw-display  M ! or          Window is moved so line with point
X                          M ^L            (with cursor) is at center of window
X
X          Grow-Window     M-X ^ or        Current window is enlarged by one
X                          M ^L            line and nearest window is shrunk by
X                                          one line
X
X          Shrink-Window   ^X-^Z           Current window is shrunk by one line
X                                          and nearest window is enlarged by one line
X
X          Clear-and-redraw ^L             Screen is blanked and redrawn.  Keeps
X                                          screen updates in sync with your commands
X
X          Scroll-Next-Up  M-^Z            Scrolls next window up by one line
X
X          Scroll-Next-Down M-^V           Scrolls next window down by one line
X
X          Delete-Window   ^X-0            Deletes current window
X
X          Delete-Other-Windows ^X-1       Deletes all but current window
X
X          Resize-Window   ^X-^W           Resizes window to a given numeric argument
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X          MicroEMACS Reference Manual                               Buffers
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X                                      Chapter 6
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X                                       Buffers
X
X
X                    We  have  already  learned  a  number  of things  about
X          buffers.    As  you will recall,  they  are  the  major  internal
X          entities  in  EMACS  --  the  place  where  editing commands  are
X          executed.  They are  characterized  by  their names, their modes,
X          and by the file with which they are associated.  Each buffer also
X          "remembers" its mark  and  point.  This convenient feature allows
X          you to go to other buffers and return to the original location in
X          the "current" buffer.
X
X                  Advanced users  of  EMACS  frequently  have  a  number of
X          buffers in the computer's memory  simultaneously.    In  the last
X          chapter, for example, you opened at least two buffers -- one into
X          the text you were  editing,  and the other into the EMACS on-line
X          tutorial.  If you deal with complex text files --  say, sectioned
X          chapters  of  a  book, you may have five or six  buffers  in  the
X          computer's memory.   You could select different buffers by simply
X          calling up the file  with  ^X-^F find-file, and let EMACS open or
X          reopen the  buffer.  However, EMACS offers fast and sophisticated
X          buffering techniques that you will find easy to  master  and much
X          more convenient to use.
X
X                  Let's begin by opening three buffers.  You  can  open any
X          three  you  choose,  for example call the  following  files  into
X          memory: fang.txt, publish.txt, and emacs.tut in the  order listed
X          here.  When you've finished this process, you'll be looking  at a
X          screen showing the EMACS tutorial.  Let's assume that you want to
X          move to the fang.txt buffer.  Enter:
X
X                  ^X-X next-buffer
X
X                  This command moves you to the next buffer.  Because EMACS
X          cycles through the  buffer  list, which is alphabetized, you will
X          now be in the fang.txt buffer. Using ^X-X again places you in the
X          publish.txt  buffer.  If  you  are  on  a  machine that  supports
X          function keys, using ^X-X again places you in  the  Function Keys
X          buffer. Using ^X-X one last time cycles you back to the beginning
X          of the list.
X
X                  If you have a large number of buffers to deal  with, this
X          cycling process may be slow and inconvenient.   The  command ^X-B
X          select-buffer allows you to  specify  the  buffer  you wish to be
X          switched  to.    When the command is entered, EMACS prompts, "Use
X
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X          Buffers                               MicroEMACS Reference Manual
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X          buffer:".  Simply enter the buffer name (NOT the file  name), and
X          that buffer will then become the current buffer.
X
X                  Multiple  buffer  manipulation  and  editing is a complex
X          activity, and you will probably  find it very inconvenient to re-
X          save each  buffer  as  you  modify  it.   The command ^X-^B list-
X          buffers creates a new  window  that  gives  details about all the
X          buffers  currently  known  to  EMACS.    Buffers  that have  been
X          modified are identified by  the  "buffer  changed"  indicator (an
X          asterisk in the second column).  You can thus quickly  and easily
X          identify buffers that need  to  be saved to files before you exit
X          EMACS.   The buffer window also  provides  other  information  --
X          buffer  specific modes, buffer size, and  buffer  name  are  also
X          listed.   To close this window,  simply  type  the  close-windows
X          command, ^X-1.
X
X                  To delete any buffer,  type  ^X-K  delete-buffer.   EMACS
X          prompts you "Kill buffer:".  Enter the buffer name  you  want  to
X          delete.    As  this  is  destructive command, EMACS will ask  for
X          confirmation if the buffer  was  changed  and  not saved.  Answer
X          Y(es) or N(o).  As usual ^G cancels the command.
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X          MicroEMACS Reference Manual                               Buffers
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X                                  Chapter 6 Summary
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X                  In Chapter 6 you learned how to manipulate buffers.
X
X          Key Binding             Keystroke                      Effect
X          Next-Buffer             ^X-^X           Switch to the next buffer in the
X                                                  buffer list
X
X          Select-Buffer           ^X-B            Switch to a particular buffer
X
X          List-Buffers            ^X-^B           List all buffers
X
X          Delete-Buffer           ^X-K            delete a particular buffer if it
X                                                  is off-screen
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X          Modes                                 MicroEMACS Reference Manual
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X                                      Chapter 7
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X                                        Modes
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X
X                  EMACS allows you to  change  the way it works in order to
X          customized it to the style of editing you  are  using.    It does
X          this by providing a number of different modes .  These  modes can
X          effect either a single buffer, or any new buffer that is created.
X          To add a mode to the  current  buffer, type ^X-M add-mode.  EMACS
X          will then prompt you for the name of  a  mode  to  add.  When you
X          type in a legal mode name,  and  type  a <NL>, EMACS will add the
X          mode  name  to  the list of current mode names in the modeline of
X          the current buffer.
X
X                  To remove an existing mode, typing the  ^X-^M delete-mode
X          will cause EMACS to prompt you for the name of  a  mode to delete
X          from the current  buffer.    This  will remove that mode from the
X          mode list on the current modeline.
X
X                  Global modes are the modes which are inherited by any new
X          buffers which are created.  For example, if you wish to always do
X          string searching with character case being significant, you would
X          want global mode EXACT to be  set  so  that any new files read in
X          inherent the EXACT mode.  Global modes are set with the  M-M add-
X          global-mode  command, and unset with the M-^M  delete-global-mode
X          command.  Also, the  current  global  modes  are displayed in the
X          first line of a ^X-^B list-buffers command.
X
X                  On machines which are capable of  displaying  colors, the
X          mode  commands  can  also  set  the  background   and  foreground
X          character colors.  Using add-mode or delete-mode with a lowercase
X          color will set the background color in the current  window.    An
X          uppercase  color will set the foreground  color  in  the  current
X          window.  Colors that EMACS knows about are: white, cyan, magenta,
X          yellow, blue, red,  green,  and  black.   If the computer you are
X          running on does not have eight colors, EMACS will attempt to make
X          some intelligent guess at what color to use when you ask  for one
X          which is not there.
X
X
X          7.1  ASAVE mode
X
X
X                  Automatic Save mode tells  EMACS  to  automatically write
X          out the current buffer to its associated file on a regular basis.
X          Normally this will be every 256 characters typed  into  the file.
X          The environment variable $ACOUNT  counts  down  to the next auto-
X
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X          save, and $ASAVE is the value used to reset $ACOUNT after  a save
X          occurs.
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X          7.2  CMODE mode
X
X
X                  CMODE is useful to C  programmers.  When CMODE is active,
X          EMACS will try to assist the user in a number of ways.  This mode
X          is set automatically with files that have a .c or .h extension.
X
X                  The <NL> key will normally  attempt to return the user to
X          the next line  at  the  same  level of indentation as the current
X          line, unless the current line ends with a open brace ({) in which
X          case the new line will be further indented by one tab position.
X
X                  A close brace (}) will delete one tab position preceeding
X          itself  as it is typed.  This should line up the close brace with
X          its matching IF, FOR or WHILE statement.
X
X                  A pound sign (#) with only leading whitespace will delete
X          all the whitespace  preceeding  itself.  This  will  always bring
X          preprocessor directives flush to the left margin.
X
X                  Whenever  any  close  fence  is  typed, ie )]>},  if  the
X          matching  open  fence  is  on  screen in the current window,  the
X          cursor will briefly  flash  to  it,  and  then  back.  This makes
X          balancing expressions, and matching blocks much easier.
X
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X          7.3  CRYPT mode
X
X
X                  When a buffer is in  CRYPT mode, it is encrypted whenever
X          it is written to a file, and decrypted when it  is  read from the
X          file.  The encryption key can be specified on  the  command  line
X          with the -k  switch,  or with the M-E set-encryption-key command.
X          If you attempt to read or  write  a  buffer in crypt mode and now
X          key has  not  been  set,  EMACS  will  execute set-encryption-key
X          automatically, prompting  you for the needed key.  Whenever EMACS
X          prompts you for a key, it will not echo the key to your screen as
X          you type it  (ie  make  SURE  you  get  it  right when you set it
X          originally).
X
X                  The encryption algorithm used changes all characters into
X          normal printing characters, thus the resulting  file  is suitable
X          for  sending  via  electronic mail.  All  version  of  MicroEMACS
X          should  be able decrypt the resulting  file  regardless  of  what
X          machine encrypted it.   Also  available  with  EMACS is the stand
X          alone  program,  MicroCRYPT,   which  can  en/decrypt  the  files
X          produced by CRYPT mode in EMACS.
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X          7.4  EXACT mode
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X                  All   string  searches   and   replacements   will   take
X          upper/lower  case into account. Normally the  case  of  a  string
X          during a search or replace is not taken into account.
X
X
X          7.5  MAGIC mode
X
X
X                  In  the  MAGIC   mode  certain  characters  gain  special
X          meanings  when  used  in a search pattern.  Collectively they are
X          know as regular expressions,  and  a  limited  number of them are
X          supported in MicroEmacs.   They  grant  greater  flexibility when
X          using the search  command.    However,  they  do  not  affect the
X          incremental search command.
X
X                  The symbols that  have  special meaning in MAGIC mode are
X          ^, $, ., &, *, [ (and ], used with it), and \.
X
X                  The  characters ^ and $ fix the  search  pattern  to  the
X          beginning  and  end  of line, respectively.  The ^ character must
X          appear  at the beginning of the search string,  and  the  $  must
X          appear at the end,  otherwise  they  loose  their meaning and are
X          treated just like any  other  character.    For example, in MAGIC
X          mode, searching for the pattern "t$" would put the cursor  at the
X          end of any line that ended with the letter 't'.    Note that this
X          is different than searching for "t<NL>", that is, 't' followed by
X          a newline character.  The character $ (and ^,  for  that  matter)
X          matches a position, not a character, so the cursor remains at the
X          end of the line.  But a  newline  is  a  character  that  must be
X          matched,  just like any other character,  which  means  that  the
X          cursor is placed just after it - on  the  beginning  of  the next
X          line.
X
X                  The character .  has a very simple meaning --  it matches
X          any  single character, except the newline.   Thus  a  search  for
X          "bad.er" could match "badger", "badder" (slang), or up to the 'r'
X          of "bad error".
X
X                  The character * is known  as closure, and means that zero
X          or  more  of  the preceding character will match.  If there is no
X          character preceding, * has no  special meaning, and since it will
X          not match  with  a  newline,  *  will  have no special meaning if
X          preceded by the beginning of line symbol ^ or the literal newline
X          character <NL>.
X
X                  The notion of zero or  more characters is important.  If,
X          for example, your cursor was on the line
X
X               This line is missing two vowels.
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X                  and  a search was made for "a*",  the  cursor  would  not
X          move, because it  is  guaranteed  to  match no letter 'a' , which
X          satifies the search conditions.  If you wanted to search  for one
X          or  more of the letter 'a', you would  search  for  "aa*",  which
X          would match the letter a, then zero or more of them.
X
X                  The character [ indicates the  beginning  of  a character
X          class.  It is similar to  the  'any'  character ., but you get to
X          choose which characters you want to match.   The  character class
X          is ended with the character ].  So,  while  a  search  for "ba.e"
X          will match "bane", "bade", "bale",  "bate",  et  cetera,  you can
X          limit  it   to  matching  "babe"  and  "bake"  by  searching  for
X          "ba[bk]e".    Only  one of the characters inside the [ and ] will
X          match  a  character.   If in fact you want to match any character
X          except those in the character class, you can put a ^ as the first
X          character.  It must be the first character of the class,  or else
X          it has no special meaning.  So, a search for [^aeiou]  will match
X          any  character except a vowel, but a  search  for  [aeiou^]  will
X          match any vowel or a ^.
X
X                  If you have a lot of characters in order that you want to
X          put in  the  character  class,  you may use a dash (-) as a range
X          character.  So, [a-z] will match any letter (or  any  lower  case
X          letter if EXACT mode is on), and [0-9a-f] will match any digit or
X          any letter 'a' through 'f', which happen to be the characters for
X          hexadecimal numbers.  If the dash is at the beginning or end of a
X          character class, it is taken to be just a dash.
X
X                  The  character & (ampersand) is a replacement  character,
X          and represents the characters which  matched  the  search string.
X          When used in the  M-R  replace-string  or the M-^R query-replace-
X          string commands, the & will be substituted for the search string.
X
X                  The escape character \ is for those times  when  you want
X          to  be  in  MAGIC mode, but also want to use a regular expression
X          character to  be  just  a  character.    It turns off the special
X          meaning of the character.  So a search for "it\." will search for
X          a line with "it.", and not "it" followed by any  other character.
X          The escape character will also let  you  put  ^, -, or ] inside a
X          character class with no special side effects.
X
X
X          7.6  OVER mode
X
X
X                  OVER mode stands for overwrite  mode.  When in this mode,
X          when characters  are typed, instead of simply inserting them into
X          the file, EMACS  will  attempt to overwrite an existing character
X          past the point.    This  is  very useful for adjusting tables and
X          diagrams.
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