Text Editing Tools

Enquiry : Mr.Jason Chan (mwchan@phy.cuhk.edu.hk, Rm348)

EMACS ---- A powerful text editor

Invoke EMACS : > emacs filename

Most emacs comands can be invoked by pressing Control Key + a letter OR Alternate Key + a letter, for example, [Ctrl+y] means holding the control key & press y. Belows are some important commands :

Get Help : [Ctrl-h]
Start Tutorial on EMACS : [Ctrl-h] t
Save File : [Ctrl-x] [Ctrl-s]
Quit EMACS : [Ctrl-x][Ctrl-c]
Undo Last Command : [Ctrl-x] u OR [Ctrl-_ ]

Cursor Movement :

[Ctrl-v] : Next Screen
[Alt-v] : Previous Screen
[Alt->] : Goto end of file
[Alt-<] : Goto beginning of file
[Ctrl-a] : Move to beginning of current line
[Ctrl-e] : Move to end of current line

Delete Text :

[Alt-d] : delete the next word after the cursor
[Ctrl-k] : delete from cursor to end of line
[Ctrl-y] : yank the deleted text back to current position

Search/Replace Text :

[Ctrl-s] text-to-search : Search text, press [Ctrl-s] to find next, [Enter] to stop search
[Alt-x] repl s[Enter]old[Enter]new[Enter] : Replace old with new

PICO --- A easy-to-use text editor

Invoke PICO : > pico filename

Basic Commands :

[Ctrl-g] : Display help pages
[Ctrl-a] : Move to beginning of line
[ctrl-e] : Move to end of line
[Ctrl-v] : Next Page
[Ctrl-Y] : Previous Page
[Ctrl-w] : Search Text
[Ctrl-l] : Refresh the display
[Ctrl-j] : Justify the current paragraph
[Ctrl-t] : Invoke the spelling checker
[Ctrl-o] : Save the buffer to a file
[Ctrl-x] : Exit & Save

VI --- A default editor on all UNIX systems

Invoke VI : > vi filename

Objectives

Identify different modes within vi
Create, save and exit a file
Add text to a file
Delete text from a file
Invoke the search and replace function
Exit with or without saving a file

Full screen editor (visual editor)
Widely use
Create and modify text only
No formatting capability
Two modes of operation

full screen command mode
full screen text editing mode

Search and replace capability for pattern matching

Cursor Movement

From command mode

  +--------+--------------------+
  | h      | left, one space    |
  +--------+--------------------+
  | j      | down, one line     |
  +--------+--------------------+
  | k      | up, one line       |
  +--------+--------------------+
  | l      | right, one space   |
  +--------+--------------------+
  | ^      | beginning of line  |
  +--------+--------------------+
  | $      | end of line        |
  +--------+--------------------+
  | 1G     | first line         |
  +--------+--------------------+
  | G      | last line          |
  +--------+--------------------+
  |[CTRL]f | forward one screen |
  +--------+--------------------+
  |[CTRL]b | backward one screen|
  +--------+--------------------+
  |[CTRL]d | down half screen   |
  +--------+--------------------+
  |[CTRL]u | up half screen     |
  +--------+--------------------+

From command or text mode

<esc> get to command mode

Create a File

Command : vi filename

if the file to be edited exists, a copy of the file is put into a buffer
if the file does not exist, an empty buffer is opened for this edit session

When vi is invoked the default mode is command mode
Use cursor keys to get to the location of first revision

Insert and Delete

a    - append or add text
         - change the editor to text input mode
         - ‘a’ will not be displayed
d$  - delete from cursor to end of line
dd  - delete the entire line
ndd - delete n lines
dw  - delete to the end of the word 
i    - insert text before cursor
o   - open a new line after cursor
O  - open a new line before cursor 
p   - put item last deleted before current line
P  - put item last deleted after current line
rx - replace current character with x
x  - delete 1 character at the cursor position

Save / Exit a File

< esc >  - change the editor to command
                 mode
:q!        - exit without saving
:w         - write the editing buffer to the file
:wq      - write and exit vi  
ZZ        - save & quit

String Search

/the/  - put the cursor on the first 
               occurrence of the string ‘the’
?the?- similar to /the/  but in opposite
               direction
n      - search next occurrence of the string
N      - similar to ‘n’ but in opposite direction

Global Search and Replace

Example :Replace every ‘ if ‘ with ‘ if and only if ‘

:g/ if /s// if and only if /g

the : moves the cursor to the ex line editor command line
first g indicates global search
the s stands for substitute
the // direct the editor to use the search string in the preceding command and replaces it with the following string
the last g stands for global

Undo

:u  -  allow command to 
           appear on screen
u   -  command will not
           appear anywhere on
           the screen
 .    - repeat last command

Environment Customization

Editor defined variables only
To see current settings from command mode, type

:set all

To set toggle variables on or off

:set nu
:set noshowmode

.exrc File

Set the vi environment on each vi session
Create a .exrc file in home directory
.exrc file is read for every vi session

Crash Recovery

After the system is restored, type

vi -r filename

List of files that have been saved

vi -r

LaTeX --- A document preparation system

Compose a LaTeX source file to DVI format : > latex myfile.tex

(Then, a file "myfile.dvi" will be generated)

Transform a DVI file to Postscript file : > dvips myfile.dvi

(Then, a file "myfile.ps" will be genrated)

Print a Postscipt file : > lpr -Plj326 myfile.ps

(Attention : only lj326, lj328 & lj204 support postscript format)

For more details about how to write a LaTeX source file, please refer to the user's guide & reference manual of LaTeX. You can borrow the book from Mr.Jason Chan.

DXNotepad --- X-window Text Editor on DEC machines

If you are using the terminal of anyone of the DEC workstations, you can invoke a X-window base text editor "dxnotepad" on the command line.

TextEdit --- X-window Text Editor on SUN machines

If you are using the terminal of anyone of the SUN workstations, you can invoke a X-window base text editor "textedit" on the command line.