Quick reference article for how to use Emacs. Yes, it is really old skool!

Cursor Motion

Key Cursor Motion
C-f Forward one character
C-b Backward one character
C-n Next line
C-p Previous line
C-a Beginning of line
C-e End of line
C-v Next screenful
M-v Previous screenful
M-< Beginning of buffer
M-> End of buffer
C-s Search forward incrementally
C-r Reverse search incrementally
C-u C-s Reg-Exp Search forward incrementally
C-u C-r Reg-Exp Reverse search incrementally
C-x C-x Swap mark and cursor
C-Space Set mark
C-l Cursor to the middle of the screen
M-} Forward one paragraph
M-{ Backward one paragraph

Text editing

Key Editing
C-q Literal command
C-d Delete next character
Backspc Delete previous character
M-% Query string replacement
M-d Delete next word
M-Bcksp Delete previous word
C-k Kill to end of line (delete to end of line)
C-w Cut region
M-w Copy region
C-y Yank most recent cut/copy (paste command)
M-y Replace yanked text with previously cut/copy text (only works immediatly after C-y or another M-y)
C-x u undo
C-u ## Repeat the next command

File Commands

Key Files
C-x C-f Open a file
C-x C-s Save buffer to file
C-x C-w Write buffer to file (Save As)
C-x C-c Exit Emacs
C-x s Save all buffers
C-x i Insert file
C-g Cancel current command
C-z Suspend/Minimize Emacs

Buffers

Key Buffers
C-x b Switch to buffer
C-x 1 Close all other buffers
C-x 2 Split current buffer in tow
C-x 3 Split current buffer horizontally
C-x 0 Close current buffer
C-x o Switch to other buffer
C-x C-b List buffers
C-x k Kill buffer
C-x ^ Grow window vertically; prefix is number of lines

Help

Key Help
C-h C-h Help menu
C-h i Info
C-h a Apropos
C-h b Key bindings
C-h m Mode help
C-h k Show command documentation; prompts for keystrokes
C-h c Show command name on message line; prompts for keystrokes
C-h f Describe function; prompts for command or function name, shows documentation in other window
C-h i Info browser; gives access to online documentation for emacs and more

Misc

Key Other
M-/ Abbreviation
M-q Autoformat current text region
C-M- Re-indent current region
C-x ( Start defining macro
C-x ) Stop macro defintion
C-x e Execute macro

C-Mode Commands

Key C-Mode
C-j Insert a newline and indent the next line.
C-c C-q Fix indentation of current function
C-c C-a Toggle the auto-newline-insertion mode. (If it was off, it will now be on and vice versa.)
C-c C-d Toggle the hungry delete mode

Extended commands

Enter ESC + [ and enter this text:

M-x Commands
c-set-style Change the indentation style
replace-string Global string replacement
revert-buffer Throw out all changes and revert to the last saved version of the file.
gdb Start GNU debugger
shell Start shell in new buffer
print-buffer Send the contents of the current buffer to the printer
compile Compile a program
set-variable Change the value of an Emacs variable to customize Emacs
artist-mode Start artist mode
artist-mode-off Exit artist mode
tabify
untabify

Tags

Use tags to navigate source code. It’s not hard to set up. This takes advantage of a popular tool called “Exuberant Ctags” (AKA ctags, or etags) that scans your source code and indexes the symbols into a TAGS file. Note: emacs comes with a tool called “etags” that does almost the same thing as Exuberant Ctags. In cygwin, the “etags” binary is actually Exuberant Ctags. Confused yet? My advice is, ignore Emacs etags, and use Exuberant Ctags, whatever it happens to be called in your part of the universe. To generate a TAGS file, do this in the root of your code tree (stick this in a script or Makefile):

#ETAGS=/cygdrive/c/emacs-21.3/bin/etags.exe
ETAGS=etags # Exuberant ctags
rm TAGS
find . -name '*.cpp' -o -name '*.h' -o -name '*.c' -print0 
     | xargs $(ETAGS) --extra=+q --fields=+fksaiS --c++-kinds=+px --append

Then, when you’re reading code and want to see the definition(s) of a symbol:

  • M-.: goes to the symbol definition
  • M-0 M-.: goes to the next matching definition
  • M-*: return to your starting point