$ Linux Command

Development

emacs

Extensible, customizable text editor and computing environment.

editortextlispdevelopmentIDE

Additional Notes

emacs (GNU Emacs) is a highly extensible, self-documenting text editor with a built-in Lisp interpreter. It can be used for editing code, writing documents, managing files, reading email, browsing the web, running a terminal, and many other tasks through its package ecosystem.

The core of Emacs is a Lisp dialect called Emacs Lisp (Elisp), which you can use to write new commands, customize existing behavior, and extend the editor in virtually any direction. It has built-in support for syntax highlighting, version control integration, project management, debugging, and a windowing system. Emacs runs in both terminal and GUI modes.

Syntax

emacs [options] [file...]

Parameters

  • file: One or more files to open for editing.

Common Options

  • -nw, --no-window-system: Run in the terminal without opening a GUI frame.
  • -Q, --quick: Start with minimal customizations (no init file).
  • --batch: Run in noninteractive batch mode for scripted processing.
  • -l file, --load file: Load a Lisp file at startup.
  • -f function, --funcall function: Call a Lisp function at startup.
  • --script file: Run a file as a script in batch mode.
  • -t file, --terminal file: Use the specified file as the terminal instead of stdin/stdout.
  • --daemon: Start Emacs as a server daemon for emacsclient.
  • --eval expr: Evaluate a Lisp expression at startup.
  • -d display, --display display: Use the specified X display.
  • -T title, --title title: Set the frame title.
  • +line: Open a file with the cursor positioned at a specific line number.

Examples

emacs

Start Emacs with the GUI.

emacs -nw

Start Emacs inside the terminal.

emacs --batch --eval '(print "hello")'

Run a Lisp expression in batch mode and print the result.

emacs --batch foo.org --load my-export.el --funcall org-html-export-to-html

Export an Org file to HTML using a batch command.

emacs -Q --eval "(package-initialize)" -f package-list-packages

Start Emacs without customizations and open the package manager.

emacs +42 file.c

Open file.c with the cursor on line 42.

emacs --daemon

Start the Emacs daemon for fast client connections.

Practical Notes

  • The Emacs tutorial is available inside Emacs: press C-h t (Ctrl+h then t).
  • The emacsclient command connects to a running Emacs daemon for nearly instant startup.
  • Key chords use modifier keys: C- is Ctrl, M- is Alt/Meta, S- is Shift.
  • Configuration is stored in ~/.emacs, ~/.emacs.el, or ~/.config/emacs/init.el.
  • Package management is built-in (M-x list-packages). Popular package repos include ELPA, MELPA, and NonGNU ELPA.
  • For basic editing: C-x C-f opens a file, C-x C-s saves, C-x C-c exits, C-s searches forward, C-_ undoes.
  • Emacs can replace a full IDE with packages for language servers (eglot/lsp-mode), project management (project.el), debugging (gud/dap-mode), and version control (magit).