This week was about Emacs. Emacs is an editor used in UNIX programming. Somebody suggests a possible derivation for the letters in Emacs as "Escape-Meta-Alt-Control-Shift" referring to its use of key combination commands. Its true in one way but Emacs is actually derived from "Editing MACRoS" - where macro is a piece of programming code that runs in Excel environment and helps automate routine tasks.
The two keys commonly used in Emacs are <Ctrl> and <Alt>. Here in this blog I use C for <Ctrl> and M(Meta) for <Alt> afterwards. Emacs look a different from all other editors. All the way down it has a small area called "mini-buffer". All the commands we type or whatever happens to the file is dispalyed in minibuffer while we play inside the editor. So always always look the mini-buffer.
To use emacs on a file
In the shell type,
emacs <filename> ($ emacs ~/learning/poem)
C-h --Help command
C-h k --Help by typing a keystroke
C-h a --Help by typing a pattern(C-h a ispell)
C-h ? --Describe how to use the help
File Reading and Writing Commands
C-x C-f --Find a file
C-x C-s --save the buffer into filename
C-x C-w --save as
Cursor/Screen Movement Commands
These commands are also applicable in shell.
C-a --Move cursor to beginning of line
C-e --Move cursor to end of line
C-f --Move cursor to forward one character
C-b --Move cursor to one character
M-f --Move cursor to forward one word
M-b --Move cursor to backward one word
C-n --Move cursor to next line
C-p --Move cursor to previous line
C-v --Scroll file forward by one screen
M-v --Scroll file backward by one screen
Mark a Region
C-space or C-@ and the move forward or backward using C-n and C-p respectively
Delete Copy Yank
In Emacs "the conventional Cut" is called Delete; and "paste" is called Yank.
C-d --Delete character under the cursor
M-d --Delete the word
C-k --Kill rest of the line
C-w --Delete a region
Some other useful commands
C-g --Keyboard quit
Modes in Emacs
Emacs contains many editing modes that alter its basic behavior in useful ways. Two types of modes. Major mode and Minor mode
Major modes provide specialized facilities for working on a particular file type, such as a C source file , or a particular type of non-file buffer, such as a shell buffer . Major modes are mutually exclusive; each buffer has one and only one major mode at any time.
Minor modes are optional features which you can turn on or off, not necessarily specific to a type of file or buffer. Minor modes are independent of one another, and of the selected major mode.
My presentation last week was about this mode.This mode is used to check the spellings of a single word or words in a whole buffer.By turning on this mode we can have all the words spelled wrong underlined on-the-fly.
Ispell offers us so many different language dictionaries. We can change dictionaries by this command below
We can check only the spellings of a particular region as
We can check spelling of whole buffer
Here above we can see the options for wrong spelled word "Watr" in the third line. We have to click 2 to get the correct word which is "Water".
Thank you for reading my blog.