GNU Emacs Lisp Reference Manual

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Emacs Lisp

This is edition 2.9 of the GNU Emacs Lisp Reference Manual, corresponding to GNU Emacs version 22.1.

Introduction: Introduction and conventions used.
Lisp Data Types: Data types of objects in Emacs Lisp.
Numbers: Numbers and arithmetic functions.
Strings and Characters: Strings, and functions that work on them.
Lists: Lists, cons cells, and related functions.
Sequences Arrays Vectors: Lists, strings and vectors are called sequences. Certain functions act on any kind of sequence. The description of vectors is here as well.
Hash Tables: Very fast lookup-tables.
Symbols: Symbols represent names, uniquely.
Evaluation: How Lisp expressions are evaluated.
Control Structures: Conditionals, loops, nonlocal exits.
Variables: Using symbols in programs to stand for values.
Functions: A function is a Lisp program that can be invoked from other functions.
Macros: Macros are a way to extend the Lisp language.
Customization: Writing customization declarations.
Loading: Reading files of Lisp code into Lisp.
Byte Compilation: Compilation makes programs run faster.
Advising Functions: Adding to the definition of a function.
Debugging: Tools and tips for debugging Lisp programs.
Read and Print: Converting Lisp objects to text and back.
Minibuffers: Using the minibuffer to read input.
Command Loop: How the editor command loop works, and how you can call its subroutines.
Keymaps: Defining the bindings from keys to commands.
Modes: Defining major and minor modes.
Documentation: Writing and using documentation strings.
Files: Accessing files.
Backups and Auto-Saving: Controlling how backups and auto-save files are made.
Buffers: Creating and using buffer objects.
Windows: Manipulating windows and displaying buffers.
Frames: Making multiple system-level windows.
Positions: Buffer positions and motion functions.
Markers: Markers represent positions and update automatically when the text is changed.
Text: Examining and changing text in buffers.
Non-ASCII Characters: Non-ASCII text in buffers and strings.
Searching and Matching: Searching buffers for strings or regexps.
Syntax Tables: The syntax table controls word and list parsing.
Abbrevs: How Abbrev mode works, and its data structures.
Processes: Running and communicating with subprocesses.
Display: Features for controlling the screen display.
System Interface: Getting the user id, system type, environment variables, and other such things.

Appendices

Antinews: Info for users downgrading to Emacs 21.
GNU Free Documentation License: The license for this documentation
GPL: Conditions for copying and changing GNU Emacs.
Tips: Advice and coding conventions for Emacs Lisp.
GNU Emacs Internals: Building and dumping Emacs; internal data structures.
Standard Errors: List of all error symbols.
Standard Buffer-Local Variables List of variables buffer-local in all buffers.
Standard Keymaps: List of standard keymaps.
Standard Hooks: List of standard hook variables.
Index: Index including concepts, functions, variables, and other terms.

--- The Detailed Node Listing --- ---------------------------------

Here are other nodes that are inferiors of those already listed, mentioned here so you can get to them in one step:

Introduction

Conventions

Some Terms: Explanation of terms we use in this manual.
nil and t: How the symbols nil and t are used.
Evaluation Notation: The format we use for examples of evaluation.
Printing Notation: The format we use for examples that print output.
Error Messages: The format we use for examples of errors.
Buffer Text Notation: The format we use for buffer contents in examples.
Format of Descriptions: Notation for describing functions, variables, etc.

Format of Descriptions

Lisp Data Types

Programming Types

Integer Type: Numbers without fractional parts.
Floating Point Type: Numbers with fractional parts and with a large range.
Character Type: The representation of letters, numbers and control characters.
Symbol Type: A multi-use object that refers to a function, variable, property list, or itself.
Sequence Type: Both lists and arrays are classified as sequences.
Cons Cell Type: Cons cells, and lists (which are made from cons cells).
Array Type: Arrays include strings and vectors.
String Type: An (efficient) array of characters.
Vector Type: One-dimensional arrays.
Char-Table Type: One-dimensional sparse arrays indexed by characters.
Bool-Vector Type: One-dimensional arrays of t or nil.
Hash Table Type: Super-fast lookup tables.
Function Type: A piece of executable code you can call from elsewhere.
Macro Type: A method of expanding an expression into another expression, more fundamental but less pretty.
Primitive Function Type: A function written in C, callable from Lisp.
Byte-Code Type: A function written in Lisp, then compiled.
Autoload Type: A type used for automatically loading seldom-used functions.

Character Type

Cons Cell and List Types

String Type

Editing Types

Buffer Type: The basic object of editing.
Marker Type: A position in a buffer.
Window Type: What makes buffers visible.
Frame Type: Windows subdivide frames.
Window Configuration Type: Recording the way a frame is subdivided.
Frame Configuration Type: Recording the status of all frames.
Process Type: A process running on the underlying OS.
Stream Type: Receive or send characters.
Keymap Type: What function a keystroke invokes.
Overlay Type: How an overlay is represented.

Numbers

Integer Basics: Representation and range of integers.
Float Basics: Representation and range of floating point.
Predicates on Numbers: Testing for numbers.
Comparison of Numbers: Equality and inequality predicates.
Numeric Conversions: Converting float to integer and vice versa.
Arithmetic Operations: How to add, subtract, multiply and divide.
Rounding Operations: Explicitly rounding floating point numbers.
Bitwise Operations: Logical and, or, not, shifting.
Math Functions: Trig, exponential and logarithmic functions.
Random Numbers: Obtaining random integers, predictable or not.

Strings and Characters

String Basics: Basic properties of strings and characters.
Predicates for Strings: Testing whether an object is a string or char.
Creating Strings: Functions to allocate new strings.
Modifying Strings: Altering the contents of an existing string.
Text Comparison: Comparing characters or strings.
String Conversion: Converting characters to strings and vice versa.
Formatting Strings: format: Emacs's analogue of printf.
Case Conversion: Case conversion functions.
Case Tables: Customizing case conversion.

Lists

Cons Cells: How lists are made out of cons cells.
List-related Predicates: Is this object a list? Comparing two lists.
List Elements: Extracting the pieces of a list.
Building Lists: Creating list structure.
List Variables: Modifying lists stored in variables.
Modifying Lists: Storing new pieces into an existing list.
Sets And Lists: A list can represent a finite mathematical set.
Association Lists: A list can represent a finite relation or mapping.
Rings: Managing a fixed-size ring of objects.

Modifying Existing List Structure

Sequences, Arrays, and Vectors

Hash Tables

Symbols

Property Lists

Evaluation

Kinds of Forms

Self-Evaluating Forms: Forms that evaluate to themselves.
Symbol Forms: Symbols evaluate as variables.
Classifying Lists: How to distinguish various sorts of list forms.
Function Indirection: When a symbol appears as the car of a list, we find the real function via the symbol.
Function Forms: Forms that call functions.
Macro Forms: Forms that call macros.
Special Forms: "Special forms" are idiosyncratic primitives, most of them extremely important.
Autoloading: Functions set up to load files containing their real definitions.

Control Structures

Nonlocal Exits

Errors

Variables

Global Variables: Variable values that exist permanently, everywhere.
Constant Variables: Certain "variables" have values that never change.
Local Variables: Variable values that exist only temporarily.
Void Variables: Symbols that lack values.
Defining Variables: A definition says a symbol is used as a variable.
Tips for Defining: Things you should think about when you define a variable.
Accessing Variables: Examining values of variables whose names are known only at run time.
Setting Variables: Storing new values in variables.
Variable Scoping: How Lisp chooses among local and global values.
Buffer-Local Variables: Variable values in effect only in one buffer.
Frame-Local Variables: Variable values in effect only in one frame.
Future Local Variables: New kinds of local values we might add some day.
File Local Variables: Handling local variable lists in files.
Variable Aliases: Variables that are aliases for other variables.
Variables with Restricted Values: Non-constant variables whose value can not be an arbitrary Lisp object.
Standard Buffer-Local Variables List of variables buffer-local in all buffers.

Scoping Rules for Variable Bindings

Buffer-Local Variables

Functions

What Is a Function: Lisp functions vs primitives; terminology.
Lambda Expressions: How functions are expressed as Lisp objects.
Function Names: A symbol can serve as the name of a function.
Defining Functions: Lisp expressions for defining functions.
Calling Functions: How to use an existing function.
Mapping Functions: Applying a function to each element of a list, etc.
Anonymous Functions: Lambda-expressions are functions with no names.
Function Cells: Accessing or setting the function definition of a symbol.
Obsolete Functions: Declaring functions obsolete.
Inline Functions: Defining functions that the compiler will open code.
Function Safety: Determining whether a function is safe to call.
Related Topics: Cross-references to specific Lisp primitives that have a special bearing on how functions work.

Lambda Expressions

Macros

Simple Macro: A basic example.
Expansion: How, when and why macros are expanded.
Compiling Macros: How macros are expanded by the compiler.
Defining Macros: How to write a macro definition.
Backquote: Easier construction of list structure.
Problems with Macros: Don't evaluate the macro arguments too many times. Don't hide the user's variables.
Indenting Macros: Specifying how to indent macro calls.

Common Problems Using Macros

Writing Customization Definitions

Customization Types

How Programs Do Loading: The load function and others.
Load Suffixes: Details about the suffixes that load tries.
Library Search: Finding a library to load.
Loading Non-ASCII: Non-ASCII characters in Emacs Lisp files.
Autoload: Setting up a function to autoload.
Repeated Loading: Precautions about loading a file twice.
Named Features: Loading a library if it isn't already loaded.
Where Defined: Finding which file defined a certain symbol.
Unloading: How to "unload" a library that was loaded.
Hooks for Loading: Providing code to be run when particular libraries are loaded.

Byte Compilation

Speed of Byte-Code: An example of speedup from byte compilation.
Compilation Functions: Byte compilation functions.
Docs and Compilation: Dynamic loading of documentation strings.
Dynamic Loading: Dynamic loading of individual functions.
Eval During Compile: Code to be evaluated when you compile.
Compiler Errors: Handling compiler error messages.
Byte-Code Objects: The data type used for byte-compiled functions.
Disassembly: Disassembling byte-code; how to read byte-code.

Advising Emacs Lisp Functions

Simple Advice: A simple example to explain the basics of advice.
Defining Advice: Detailed description of defadvice.
Around-Advice: Wrapping advice around a function's definition.
Computed Advice: ...is to defadvice as fset is to defun.
Activation of Advice: Advice doesn't do anything until you activate it.
Enabling Advice: You can enable or disable each piece of advice.
Preactivation: Preactivation is a way of speeding up the loading of compiled advice.
Argument Access in Advice: How advice can access the function's arguments.
Advising Primitives: Accessing arguments when advising a primitive.
Combined Definition: How advice is implemented.

Debugging Lisp Programs

The Lisp Debugger

Error Debugging: Entering the debugger when an error happens.
Infinite Loops: Stopping and debugging a program that doesn't exit.
Function Debugging: Entering it when a certain function is called.
Explicit Debug: Entering it at a certain point in the program.
Using Debugger: What the debugger does; what you see while in it.
Debugger Commands: Commands used while in the debugger.
Invoking the Debugger: How to call the function debug.
Internals of Debugger: Subroutines of the debugger, and global variables.

Edebug

Using Edebug: Introduction to use of Edebug.
Instrumenting: You must instrument your code in order to debug it with Edebug.
Edebug Execution Modes: Execution modes, stopping more or less often.
Jumping: Commands to jump to a specified place.
Edebug Misc: Miscellaneous commands.
Breaks: Setting breakpoints to make the program stop.
Trapping Errors: Trapping errors with Edebug.
Edebug Views: Views inside and outside of Edebug.
Edebug Eval: Evaluating expressions within Edebug.
Eval List: Expressions whose values are displayed each time you enter Edebug.
Printing in Edebug: Customization of printing.
Trace Buffer: How to produce trace output in a buffer.
Coverage Testing: How to test evaluation coverage.
The Outside Context: Data that Edebug saves and restores.
Edebug and Macros: Specifying how to handle macro calls.
Edebug Options: Option variables for customizing Edebug.

Debugging Invalid Lisp Syntax

Reading and Printing Lisp Objects

Streams Intro: Overview of streams, reading and printing.
Input Streams: Various data types that can be used as input streams.
Input Functions: Functions to read Lisp objects from text.
Output Streams: Various data types that can be used as output streams.
Output Functions: Functions to print Lisp objects as text.
Output Variables: Variables that control what the printing functions do.

Minibuffers

Intro to Minibuffers: Basic information about minibuffers.
Text from Minibuffer: How to read a straight text string.
Object from Minibuffer: How to read a Lisp object or expression.
Minibuffer History: Recording previous minibuffer inputs so the user can reuse them.
Initial Input: Specifying initial contents for the minibuffer.
Completion: How to invoke and customize completion.
Yes-or-No Queries: Asking a question with a simple answer.
Multiple Queries: Asking a series of similar questions.
Reading a Password: Reading a password from the terminal.
Minibuffer Commands: Commands used as key bindings in minibuffers.
Minibuffer Contents: How such commands access the minibuffer text.
Minibuffer Windows: Operating on the special minibuffer windows.
Recursive Mini: Whether recursive entry to minibuffer is allowed.
Minibuffer Misc: Various customization hooks and variables.

Completion

Basic Completion: Low-level functions for completing strings. (These are too low level to use the minibuffer.)
Minibuffer Completion: Invoking the minibuffer with completion.
Completion Commands: Minibuffer commands that do completion.
High-Level Completion: Convenient special cases of completion (reading buffer name, file name, etc.)
Reading File Names: Using completion to read file names.
Programmed Completion: Finding the completions for a given file name.

Command Loop

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.
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.

Defining Commands

Input Events

Keyboard Events: Ordinary characters--keys with symbols on them.
Function Keys: Function keys--keys with names, not symbols.
Mouse Events: Overview of mouse events.
Click Events: Pushing and releasing a mouse button.
Drag Events: Moving the mouse before releasing the button.
Button-Down Events: A button was pushed and not yet released.
Repeat Events: Double and triple click (or drag, or down).
Motion Events: Just moving the mouse, not pushing a button.
Focus Events: Moving the mouse between frames.
Misc Events: Other events the system can generate.
Event Examples: Examples of the lists for mouse events.
Classifying Events: Finding the modifier keys in an event symbol.
Accessing Events: Functions to extract info from events.
Strings of Events: Special considerations for putting keyboard character events in a string.

Reading Input

Keymaps

Key Sequences: Key sequences as Lisp objects.
Keymap Basics: Basic concepts of keymaps.
Format of Keymaps: What a keymap looks like as a Lisp object.
Creating Keymaps: Functions to create and copy keymaps.
Inheritance and Keymaps: How one keymap can inherit the bindings of another keymap.
Prefix Keys: Defining a key with a keymap as its definition.
Active Keymaps: How Emacs searches the active keymaps for a key binding.
Searching Keymaps: A pseudo-Lisp summary of searching active maps.
Controlling Active Maps: Each buffer has a local keymap to override the standard (global) bindings. A minor mode can also override them.
Key Lookup: How extracting elements from keymaps works.
Functions for Key Lookup: How to request key lookup.
Changing Key Bindings: Redefining a key in a keymap.
Remapping Commands: A keymap can translate one command to another.
Translation Keymaps: Keymaps for translating sequences of events.
Key Binding Commands: Interactive interfaces for redefining keys.
Scanning Keymaps: Looking through all keymaps, for printing help.
Menu Keymaps: A keymap can define a menu for X or for use from the terminal.
Standard Keymaps: List of standard keymaps.

Major and Minor Modes

Hooks: How to use hooks; how to write code that provides hooks.
Major Modes: Defining major modes.
Minor Modes: Defining minor modes.
Mode Line Format: Customizing the text that appears in the mode line.
Imenu: How a mode can provide a menu of definitions in the buffer.
Font Lock Mode: How modes can highlight text according to syntax.
Desktop Save Mode: How modes can have buffer state saved between Emacs sessions.

Menu Keymaps

Defining Menus

Major and Minor Modes

Hooks: How to use hooks; how to write code that provides hooks.
Major Modes: Defining major modes.
Minor Modes: Defining minor modes.
Mode Line Format: Customizing the text that appears in the mode line.
Imenu: How a mode can provide a menu of definitions in the buffer.
Font Lock Mode: How modes can highlight text according to syntax.
Desktop Save Mode: How modes can have buffer state saved between Emacs sessions.

Major Modes

Major Mode Basics
Major Mode Conventions: Coding conventions for keymaps, etc.
Example Major Modes: Text mode and Lisp modes.
Auto Major Mode: How Emacs chooses the major mode automatically.
Mode Help: Finding out how to use a mode.
Derived Modes: Defining a new major mode based on another major mode.
Generic Modes: Defining a simple major mode that supports comment syntax and Font Lock mode.
Mode Hooks: Hooks run at the end of major mode functions.

Minor Modes

Mode Line Format

Font Lock Mode

Font Lock Basics: Overview of customizing Font Lock.
Search-based Fontification: Fontification based on regexps.
Customizing Keywords: Customizing search-based fontification.
Other Font Lock Variables: Additional customization facilities.
Levels of Font Lock: Each mode can define alternative levels so that the user can select more or less.
Precalculated Fontification: How Lisp programs that produce the buffer contents can also specify how to fontify it.
Faces for Font Lock: Special faces specifically for Font Lock.
Syntactic Font Lock: Fontification based on syntax tables.
Setting Syntax Properties: Defining character syntax based on context using the Font Lock mechanism.
Multiline Font Lock: How to coerce Font Lock into properly highlighting multiline constructs.

Multiline Font Lock Constructs

Documentation

Files

Visiting Files: Reading files into Emacs buffers for editing.
Saving Buffers: Writing changed buffers back into files.
Reading from Files: Reading files into other buffers.
Writing to Files: Writing new files from parts of buffers.
File Locks: Locking and unlocking files, to prevent simultaneous editing by two people.
Information about Files: Testing existence, accessibility, size of files.
Changing Files: Renaming files, changing protection, etc.
File Names: Decomposing and expanding file names.
Contents of Directories: Getting a list of the files in a directory.
Create/Delete Dirs: Creating and Deleting Directories.
Magic File Names: Defining "magic" special handling for certain file names.
Format Conversion: Conversion to and from various file formats.

Visiting Files

Information about Files

File Names

File Name Components: The directory part of a file name, and the rest.
Relative File Names: Some file names are relative to a current directory.
Directory Names: A directory's name as a directory is different from its name as a file.
File Name Expansion: Converting relative file names to absolute ones.
Unique File Names: Generating names for temporary files.
File Name Completion: Finding the completions for a given file name.
Standard File Names: If your package uses a fixed file name, how to handle various operating systems simply.

Backups and Auto-Saving

Backup Files

Buffers

Buffer Basics: What is a buffer?
Current Buffer: Designating a buffer as current so primitives will access its contents.
Buffer Names: Accessing and changing buffer names.
Buffer File Name: The buffer file name indicates which file is visited.
Buffer Modification: A buffer is modified if it needs to be saved.
Modification Time: Determining whether the visited file was changed ``behind Emacs's back''.
Read Only Buffers: Modifying text is not allowed in a read-only buffer.
The Buffer List: How to look at all the existing buffers.
Creating Buffers: Functions that create buffers.
Killing Buffers: Buffers exist until explicitly killed.
Indirect Buffers: An indirect buffer shares text with some other buffer.
Buffer Gap: The gap in the buffer.

Windows

Basic Windows: Basic information on using windows.
Splitting Windows: Splitting one window into two windows.
Deleting Windows: Deleting a window gives its space to other windows.
Selecting Windows: The selected window is the one that you edit in.
Cyclic Window Ordering: Moving around the existing windows.
Buffers and Windows: Each window displays the contents of a buffer.
Displaying Buffers: Higher-level functions for displaying a buffer and choosing a window for it.
Choosing Window: How to choose a window for displaying a buffer.
Window Point: Each window has its own location of point.
Window Start: The display-start position controls which text is on-screen in the window.
Textual Scrolling: Moving text up and down through the window.
Vertical Scrolling: Moving the contents up and down on the window.
Horizontal Scrolling: Moving the contents sideways on the window.
Size of Window: Accessing the size of a window.
Resizing Windows: Changing the size of a window.
Coordinates and Windows: Converting coordinates to windows.
Window Tree: The layout and sizes of all windows in a frame.
Window Configurations: Saving and restoring the state of the screen.
Window Hooks: Hooks for scrolling, window size changes, redisplay going past a certain point, or window configuration changes.

Frames

Creating Frames: Creating additional frames.
Multiple Displays: Creating frames on other displays.
Frame Parameters: Controlling frame size, position, font, etc.
Frame Titles: Automatic updating of frame titles.
Deleting Frames: Frames last until explicitly deleted.
Finding All Frames: How to examine all existing frames.
Frames and Windows: A frame contains windows; display of text always works through windows.
Minibuffers and Frames: How a frame finds the minibuffer to use.
Input Focus: Specifying the selected frame.
Visibility of Frames: Frames may be visible or invisible, or icons.
Raising and Lowering: Raising a frame makes it hide other windows; lowering it puts it underneath the others.
Frame Configurations: Saving the state of all frames.
Mouse Tracking: Getting events that say when the mouse moves.
Mouse Position: Asking where the mouse is, or moving it.
Pop-Up Menus: Displaying a menu for the user to select from.
Dialog Boxes: Displaying a box to ask yes or no.
Pointer Shape: Specifying the shape of the mouse pointer.
Window System Selections: Transferring text to and from other windows.
Drag and Drop: Internals of Drag-and-Drop implementation.
Color Names: Getting the definitions of color names.
Text Terminal Colors: Defining colors for text-only terminals.
Resources: Getting resource values from the server.
Display Feature Testing: Determining the features of a terminal.

Frame Parameters

Window Frame Parameters

Basic Parameters: Parameters that are fundamental.
Position Parameters: The position of the frame on the screen.
Size Parameters: Frame's size.
Layout Parameters: Size of parts of the frame, and enabling or disabling some parts.
Buffer Parameters: Which buffers have been or should be shown.
Management Parameters: Communicating with the window manager.
Cursor Parameters: Controlling the cursor appearance.
Color Parameters: Colors of various parts of the frame.

Positions

Motion

Markers

Overview of Markers: The components of a marker, and how it relocates.
Predicates on Markers: Testing whether an object is a marker.
Creating Markers: Making empty markers or markers at certain places.
Information from Markers: Finding the marker's buffer or character position.
Marker Insertion Types: Two ways a marker can relocate when you insert where it points.
Moving Markers: Moving the marker to a new buffer or position.
The Mark: How "the mark" is implemented with a marker.
The Region: How to access "the region".

Text

Near Point: Examining text in the vicinity of point.
Buffer Contents: Examining text in a general fashion.
Comparing Text: Comparing substrings of buffers.
Insertion: Adding new text to a buffer.
Commands for Insertion: User-level commands to insert text.
Deletion: Removing text from a buffer.
User-Level Deletion: User-level commands to delete text.
The Kill Ring: Where removed text sometimes is saved for later use.
Undo: Undoing changes to the text of a buffer.
Maintaining Undo: How to enable and disable undo information. How to control how much information is kept.
Filling: Functions for explicit filling.
Margins: How to specify margins for filling commands.
Adaptive Fill: Adaptive Fill mode chooses a fill prefix from context.
Auto Filling: How auto-fill mode is implemented to break lines.
Sorting: Functions for sorting parts of the buffer.
Columns: Computing horizontal positions, and using them.
Indentation: Functions to insert or adjust indentation.
Case Changes: Case conversion of parts of the buffer.
Text Properties: Assigning Lisp property lists to text characters.
Substitution: Replacing a given character wherever it appears.
Transposition: Swapping two portions of a buffer.
Registers: How registers are implemented. Accessing the text or position stored in a register.
Base 64: Conversion to or from base 64 encoding.
MD5 Checksum: Compute the MD5 "message digest"/"checksum".
Atomic Changes: Installing several buffer changes "atomically".
Change Hooks: Supplying functions to be run when text is changed.

The Kill Ring

Indentation

Text Properties

Examining Properties: Looking at the properties of one character.
Changing Properties: Setting the properties of a range of text.
Property Search: Searching for where a property changes value.
Special Properties: Particular properties with special meanings.
Format Properties: Properties for representing formatting of text.
Sticky Properties: How inserted text gets properties from neighboring text.
Saving Properties: Saving text properties in files, and reading them back.
Lazy Properties: Computing text properties in a lazy fashion only when text is examined.
Clickable Text: Using text properties to make regions of text do something when you click on them.
Links and Mouse-1: How to make <Mouse-1> follow a link.
Fields: The field property defines fields within the buffer.
Not Intervals: Why text properties do not use Lisp-visible text intervals.

Non-ASCII Characters

Text Representations: Unibyte and multibyte representations
Converting Representations: Converting unibyte to multibyte and vice versa.
Selecting a Representation: Treating a byte sequence as unibyte or multi.
Character Codes: How unibyte and multibyte relate to codes of individual characters.
Character Sets: The space of possible character codes is divided into various character sets.
Chars and Bytes: More information about multibyte encodings.
Splitting Characters: Converting a character to its byte sequence.
Scanning Charsets: Which character sets are used in a buffer?
Translation of Characters: Translation tables are used for conversion.
Coding Systems: Coding systems are conversions for saving files.
Input Methods: Input methods allow users to enter various non-ASCII characters without special keyboards.
Locales: Interacting with the POSIX locale.

Coding Systems

Coding System Basics: Basic concepts.
Encoding and I/O: How file I/O functions handle coding systems.
Lisp and Coding Systems: Functions to operate on coding system names.
User-Chosen Coding Systems: Asking the user to choose a coding system.
Default Coding Systems: Controlling the default choices.
Specifying Coding Systems: Requesting a particular coding system for a single file operation.
Explicit Encoding: Encoding or decoding text without doing I/O.
Terminal I/O Encoding: Use of encoding for terminal I/O.
MS-DOS File Types: How DOS "text" and "binary" files relate to coding systems.

Searching and Matching

String Search: Search for an exact match.
Searching and Case: Case-independent or case-significant searching.
Regular Expressions: Describing classes of strings.
Regexp Search: Searching for a match for a regexp.
POSIX Regexps: Searching POSIX-style for the longest match.
Match Data: Finding out which part of the text matched, after a string or regexp search.
Search and Replace: Commands that loop, searching and replacing.
Standard Regexps: Useful regexps for finding sentences, pages,...

Regular Expressions

Syntax of Regular Expressions

The Match Data

Syntax Tables

Syntax Basics: Basic concepts of syntax tables.
Syntax Descriptors: How characters are classified.
Syntax Table Functions: How to create, examine and alter syntax tables.
Syntax Properties: Overriding syntax with text properties.
Motion and Syntax: Moving over characters with certain syntaxes.
Parsing Expressions: Parsing balanced expressions using the syntax table.
Standard Syntax Tables: Syntax tables used by various major modes.
Syntax Table Internals: How syntax table information is stored.
Categories: Another way of classifying character syntax.

Syntax Descriptors

Parsing Expressions

Abbrevs And Abbrev Expansion

Processes

Subprocess Creation: Functions that start subprocesses.
Shell Arguments: Quoting an argument to pass it to a shell.
Synchronous Processes: Details of using synchronous subprocesses.
Asynchronous Processes: Starting up an asynchronous subprocess.
Deleting Processes: Eliminating an asynchronous subprocess.
Process Information: Accessing run-status and other attributes.
Input to Processes: Sending input to an asynchronous subprocess.
Signals to Processes: Stopping, continuing or interrupting an asynchronous subprocess.
Output from Processes: Collecting output from an asynchronous subprocess.
Sentinels: Sentinels run when process run-status changes.
Query Before Exit: Whether to query if exiting will kill a process.
Transaction Queues: Transaction-based communication with subprocesses.
Network: Opening network connections.
Network Servers: Network servers let Emacs accept net connections.
Datagrams: UDP network connections.
Low-Level Network: Lower-level but more general function to create connections and servers.
Misc Network: Additional relevant functions for network connections.
Byte Packing: Using bindat to pack and unpack binary data.

Receiving Output from Processes

Low-Level Network Access

Packing and Unpacking Byte Arrays

Emacs Display

Refresh Screen: Clearing the screen and redrawing everything on it.
Forcing Redisplay: Forcing redisplay.
Truncation: Folding or wrapping long text lines.
The Echo Area: Displaying messages at the bottom of the screen.
Warnings: Displaying warning messages for the user.
Invisible Text: Hiding part of the buffer text.
Selective Display: Hiding part of the buffer text (the old way).
Temporary Displays: Displays that go away automatically.
Overlays: Use overlays to highlight parts of the buffer.
Width: How wide a character or string is on the screen.
Line Height: Controlling the height of lines.
Faces: A face defines a graphics style for text characters: font, colors, etc.
Fringes: Controlling window fringes.
Scroll Bars: Controlling vertical scroll bars.
Display Property: Enabling special display features.
Images: Displaying images in Emacs buffers.
Buttons: Adding clickable buttons to Emacs buffers.
Abstract Display: Emacs' Widget for Object Collections.
Blinking: How Emacs shows the matching open parenthesis.
Usual Display: The usual conventions for displaying nonprinting chars.
Display Tables: How to specify other conventions.
Beeping: Audible signal to the user.
Window Systems: Which window system is being used.

The Echo Area

Reporting Warnings

Overlays

Faces

Defining Faces: How to define a face with defface.
Face Attributes: What is in a face?
Attribute Functions: Functions to examine and set face attributes.
Displaying Faces: How Emacs combines the faces specified for a character.
Font Selection: Finding the best available font for a face.
Face Functions: How to define and examine faces.
Auto Faces: Hook for automatic face assignment.
Font Lookup: Looking up the names of available fonts and information about them.
Fontsets: A fontset is a collection of fonts that handle a range of character sets.

Fringes

The display Property

Images

Image Descriptors: How to specify an image for use in :display.
XBM Images: Special features for XBM format.
XPM Images: Special features for XPM format.
GIF Images: Special features for GIF format.
PostScript Images: Special features for PostScript format.
Other Image Types: Various other formats are supported.
Defining Images: Convenient ways to define an image for later use.
Showing Images: Convenient ways to display an image once it is defined.
Image Cache: Internal mechanisms of image display.

Buttons

Abstract Display

Display Tables

Operating System Interface

Starting Up: Customizing Emacs start-up processing.
Getting Out: How exiting works (permanent or temporary).
System Environment: Distinguish the name and kind of system.
User Identification: Finding the name and user id of the user.
Time of Day: Getting the current time.
Time Conversion: Converting a time from numeric form to a string, or to calendrical data (or vice versa).
Time Parsing: Converting a time from numeric form to text and vice versa.
Processor Run Time: Getting the run time used by Emacs.
Time Calculations: Adding, subtracting, comparing times, etc.
Timers: Setting a timer to call a function at a certain time.
Idle Timers: Setting a timer to call a function when Emacs has been idle for a certain length of time.
Terminal Input: Accessing and recording terminal input.
Terminal Output: Controlling and recording terminal output.
Sound Output: Playing sounds on the computer's speaker.
X11 Keysyms: Operating on key symbols for X Windows
Batch Mode: Running Emacs without terminal interaction.
Session Management: Saving and restoring state with X Session Management.

Starting Up Emacs

Getting Out of Emacs

Terminal Input

Tips and Conventions

Coding Conventions: Conventions for clean and robust programs.
Key Binding Conventions: Which keys should be bound by which programs.
Programming Tips: Making Emacs code fit smoothly in Emacs.
Compilation Tips: Making compiled code run fast.
Warning Tips: Turning off compiler warnings.
Documentation Tips: Writing readable documentation strings.
Comment Tips: Conventions for writing comments.
Library Headers: Standard headers for library packages.

GNU Emacs Internals

Object Internals