Glk API Specification

API version 0.6.1

Andrew Plotkin <erkyrath@eblong.com>

Copyright 1998-2000 by Andrew Plotkin. You have permission to display, download, and print this document, provided that you do so for personal, non-commercial use only. You may not modify or distribute this document without the author's written permission.

This document and further Glk information can be found at: http://www.eblong.com/zarf/glk/

0. Introduction
0.1. What Glk Is
0.2. What About Java?
0.3. What About the Virtual Machine?
0.4. What Does Glk Not Do?
0.5. Conventions of This Document
1. Overall Structure
1.1. Your Program's Main Function
1.2. Exiting Your Program
1.3. The Interrupt Handler
1.4. The Tick Thing
1.5. Basic Types
1.6. Opaque Objects
1.6.1. Rocks
1.6.2. Iterating Through Opaque Objects
1.7. The Gestalt System
1.8. The Version Number
1.9. Other API Conventions
2. Character Encoding
2.1. Output
2.2. Line Input
2.3. Character Input
2.4. Upper and Lower Case
3. Windows
3.1. Window Arrangement
3.2. Window Opening, Closing, and Constraints
3.3. Changing Window Constraints
3.4. A Note on Display Style
3.5. The Types of Windows
3.5.1. Blank Windows
3.5.2. Pair Windows
3.5.3. Text Buffer Windows
3.5.4. Text Grid Windows
3.5.5. Graphics Windows
3.6. Echo Streams
3.7. Other Window Functions
4. Events
4.1. Character Input Events
4.2. Line Input Events
4.3. Mouse Input Events
4.4. Timer Events
4.5. Window Arrangement Events
4.6. Window Redrawing Events
4.7. Sound Notification Events
4.8. Hyperlink Events
4.9. Other Events
5. Streams
5.1. How To Print
5.2. How To Read
5.3. Closing Streams
5.4. Stream Positions
5.5. Styles
5.5.1. Suggesting the Appearance of Styles
5.5.2. Testing the Appearance of Styles
5.6. The Types of Streams
5.6.1. Window Streams
5.6.2. Memory Streams
5.6.3. File Streams
5.7. Other Stream Functions
6. File References
6.1. The Types of File References
6.2. Other File Reference Functions
7. Graphics
7.1. Image Resources
7.2. Graphics in Graphics Windows
7.3. Graphics in Text Buffer Windows
7.4. Testing for Graphics Capabilities
8. Sound
8.1. Sound Resources
8.2. Creating and Destroying Sound Channels
8.3. Playing Sounds
8.4. Other Sound Channel Functions
8.5. Testing for Sound Capabilities
9. Hyperlinks
9.1. Creating Hyperlinks
9.2. Accepting Hyperlink Events
9.3. Testing for Hyperlink Capabilities
10. Porting, Adapting, and Other Messy Bits
10.1. Startup Options
10.2. Going Outside the Glk API
10.2.1. Memory Management
10.2.2. String Manipulation
10.2.3. File Handling
10.2.4. Private Extensions to Glk
10.3. Glk and the Virtual Machine
10.3.1. Implementing a Higher Layer Over Glk
10.3.2. Glk as a VM's Native API
11. Appendices
11.1. The Dispatch Layer
11.1.1. How This Works
11.1.2. Interrogating the Interface
11.1.3. Dispatching
11.1.3.1. Basic Types
11.1.3.2. References
11.1.3.3. Structures
11.1.3.4. Arrays
11.1.3.5. Return Values
11.1.4. Getting Argument Prototypes
11.1.5. Functions the Library Must Provide
11.1.5.1. Opaque Object Registry
11.1.5.2. Retained Array Registry
11.1.6. Table of Selectors
11.2. The Blorb Layer
11.2.1. How This Works
11.2.2. What the Program Does
11.2.3. What the Library Does
11.2.4. What the Blorb Layer Does
11.2.5. Blorb Errors