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ex(1)

vi(1)



     edit(1)                    DG/UX 4.30                     edit(1)



     NAME
          edit - text editor (variant of ex for casual users)

     SYNOPSIS
          edit [ -r ] [ -x ] [ -C ] name ...

     DESCRIPTION
          Edit is a variant of the text editor ex recommended for new
          or casual users who wish to use a command-oriented editor.
          The following brief introduction should help you get started
          with edit.  If you are using a CRT terminal you may want to
          learn about the display editor vi(1).

     OPTIONS
          -r   Recover file after an editor or system crash.  If file
               is not specified, a list of all saved files will be
               printed.

          -x   Encryption option; when used, the file will be
               encrypted when it is written and will require an
               encryption key to be read.  When reading a file, edit
               makes an educated guess as to whether the file is
               encrypted or not.  See crypt(1).

          -C   Encryption option; same as -x except that when reading
               in a file, edit assumes that the file is encrypted.

     BRIEF INTRODUCTION
          To edit the contents of an existing file you begin with the
          command "edit name" to the shell.  Edit makes a copy of the
          file which you can then edit, and tells you how many lines
          and characters are in the file.  To create a new file, just
          make up a name for the file and invoke edit with the
          filename.  If no file by that name already exists, edit will
          create one and print [NEW FILE] on your screen.

          Edit prompts for commands with the character `:', which you
          should see after starting the editor.  If you are editing an
          existing file, then you will have some lines in edit's
          buffer (its name for the copy of the file you are editing).
          Most commands to edit use its "current line" if you do not
          tell them which line to use.  When you invoke edit for an
          existing file, the last line of the file is your current
          line.  If you type print (which can be abbreviated p) and
          press Newline (as you should after all edit commands) the
          current line will be printed.  If you delete (d) the current
          line, edit will print the new current line, which is
          typically the next line in the file.  If you delete this
          last line, then the new last line becomes the current one.
          In general, after a delete, the next line in the file
          becomes the current line.  (Deleting the last line is a
          special case.)



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     edit(1)                    DG/UX 4.30                     edit(1)



          If you start with an empty file or wish to add some new
          lines, then the append (a) command can be used.  After you
          give this command (typing a Newline after the word append)
          edit will read lines from your terminal until you give a
          line consisting of just a ".", placing these lines after the
          current line.  The last line you type then becomes the
          current line.  The command insert (i) is like append but
          places the lines you give before, rather than after, the
          current line.

          Edit numbers the lines in the buffer, with the first line
          having number 1.  If you give the command "1" then edit will
          print this first line.  If you then give the command delete
          edit will delete the first line, line 2 will become line 1,
          and edit will print the current line (the new line 1) so you
          can see where you are.  In general, the current line will
          always be the last line affected by a command.

          You can make a change to some text within the current line
          by using the substitute (s) command.  You type "s/old/new/"
          where old is the old characters you want to get rid of and
          new is the new characters you want to replace old with.

          The command file (f) will tell you how many lines there are
          in the buffer you are editing and will print "[Modified]" if
          you have changed the buffer.  After modifying a file you can
          replace the file with the buffer text by giving a write (w)
          command.  You can then leave the editor by issuing a quit
          (q) command.  If you run edit on a file, but do not change
          it, it is not necessary (but does no harm) to write the file
          back.  If you try to quit from edit after modifying the
          buffer without writing it out, you will be warned that there
          has been "No write since last change (:quit! overrides)" and
          edit will await another command.  If you wish not to write
          the buffer out then you can issue another quit! command
          (note the exclamation point).  The buffer is then
          irretrievably discarded, and you return to the shell.

          By using the delete and append commands, and giving line
          numbers to see lines in the file you can make any changes
          you desire.  You should learn at least a few more things,
          however, if you are to use edit more than a few times.

          The change (c) command will change the current line to a
          sequence of lines you supply (as with append you add lines
          up to a line consisting of only a ".").  You can tell change
          to change more than one line by giving the line numbers of
          the lines you want to change, e.g., "3,5change".  You can
          print lines this way too.  Thus "1,23p" prints the first 23
          lines of the file.

          The undo (u) command will reverse the effect of the last



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     edit(1)                    DG/UX 4.30                     edit(1)



          command you gave which changed the buffer.  Thus if you give
          a substitute command which does not do what you want, you
          can type undo and the old contents of the lines will be
          restored.  You can also undo an undo command so that you can
          continue to change your mind.  Edit will give you a warning
          message when your commands affect more than one line of the
          buffer.  If the amount of change seems unreasonable, you
          should consider doing an undo and looking to see what
          happened.  If you decide that the change is ok, then you can
          type undo again to get it back.  Note that commands such as
          write and quit cannot be undone.

          To look at the next line in the buffer you can just hit
          Newline.  To look at a number of lines type ^D (the control
          key and, while it is held down, the D key, then let up both)
          rather than Newline.  This will show you a half screen of
          lines on a CRT or 12 lines on a hardcopy terminal.  You can
          look at the text around where you are by giving the command
          "z.".  The current line will then be the last line printed;
          you can get back to the line where you were before the "z."
          command by typing "''".  The z command can also be given
          other following characters: "z-" prints a screen of text (or
          24 lines) ending at the current line; "z+" prints the next
          screenful.  If you want less than a screenful of lines, type
          in "z.11" to get 11 lines total (your former current line is
          now in the center of the 11 lines, and the last line printed
          is your new current line).  This method of giving counts
          works in general; thus you can delete 5 lines starting with
          the current line with the command "delete 5".

          To find things in the file, you can use line numbers if you
          happen to know them.  However, since the line numbers change
          when you insert and delete lines, this is somewhat
          unreliable.  You can search backwards and forwards in the
          file for strings by giving commands of the form /text/ to
          search forward for text or ?text?  to search backward for
          text.  If a search reaches the end of the file without
          finding the text it wraps around to the other end of the
          file and continues to search back to the line where you are.
          A useful feature here is a search of the form /^text/ which
          searches for text at the beginning of a line.  Similarly
          /text$/ searches for text at the end of a line.  You can
          leave off the trailing / or ? in these commands.

          The current line has a symbolic name "."; this is most
          useful in a range of lines as in ".,$print" which prints the
          rest of the lines in the file.  To get to the last line in
          the file you can refer to it by its symbolic name "$".  Thus
          the command "$ delete" or "$d" deletes the last line in the
          file, no matter which line was the current line before.
          Arithmetic with line references is also possible.  Thus the
          line "$-5" is the fifth before the last, and ".+20" is 20



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     edit(1)                    DG/UX 4.30                     edit(1)



          lines after the current.

          You can find out which line you are at by typing ".=".  This
          is useful if you wish to move or copy a section of text
          within a file or between files.  Find out the first and last
          line numbers you wish to copy or move (e.g., 10 to 20).  For
          a move you can then type "10,20delete a" which deletes these
          lines from the file and places them in a buffer named a.
          Edit has 26 such buffers named a through z.  You can later
          get these lines back by doing "put a" to put the contents of
          buffer a after the current line.  If you want to move or
          copy these lines between files you can give an edit (e)
          command after copying the lines, following it with the name
          of the other file you wish to edit, e.g., "edit chapter2".
          By changing delete to yank above you can get a command for
          copying lines.  If the text you wish to move or copy is all
          within one file then you can just type "10,20move $" for
          example.  It is not necessary to use named buffers in this
          case (but you can if you wish).

     SEE ALSO
          ex(1), vi(1).

































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