21 Command Loop

When you run Emacs, it enters the editor command loop almost immediately. This loop reads key sequences, executes their definitions, and displays the results. In this chapter, we describe how these things are done, and the subroutines that allow Lisp programs to do them.

• Command Overview		How the command loop reads commands.
• Defining Commands		Specifying how a function should read arguments.
• Interactive Call		Calling a command, so that it will read arguments.
• Distinguish Interactive		Making a command distinguish interactive calls.
• Command Loop Info		Variables set by the command loop for you to examine.
• Adjusting Point		Adjustment of point after a command.
• Input Events		What input looks like when you read it.
• Reading Input		How to read input events from the keyboard or mouse.
• Special Events		Events processed immediately and individually.
• Waiting		Waiting for user input or elapsed time.
• Quitting		How C-g works. How to catch or defer quitting.
• Prefix Command Arguments		How the commands to set prefix args work.
• Recursive Editing		Entering a recursive edit, and why you usually shouldn’t.
• Disabling Commands		How the command loop handles disabled commands.
• Command History		How the command history is set up, and how accessed.
• Keyboard Macros		How keyboard macros are implemented.