Glulx is a 32-bit

portable Portable may refer to: General * Portable building, a manufactured structure that is built off site and moved in upon completion of site and utility work * Portable classroom, a temporary building installed on the grounds of a school to provide ...

virtual machine In computing, a virtual machine (VM) is the virtualization/ emulation of a computer system. Virtual machines are based on computer architectures and provide functionality of a physical computer. Their implementations may involve specialized h ...

intended for writing and playing interactive fiction. It was designed by

Andrew Plotkin Andrew Plotkin (born May 15, 1970), also known as Zarf, is a central figure in the modern interactive fiction (IF) community. Having both written a number of award-winning games and developed a range of new file formats, interpreters, and other u ...

to relieve some of the restrictions in the venerable

Z-machine The Z-machine is a virtual machine that was developed by Joel Berez and Marc Blank in 1979 and used by Infocom for its text adventure games. Infocom compiled game code to files containing Z-machine instructions (called story files or Z-code ...

format. For example, the Z-machine provides native support for 16-bit integers, while Glulx natively supports 32-bit integers.

Versions and popularity

The

Inform Inform is a programming language and design system for interactive fiction originally created in 1993 by Graham Nelson. Inform can generate programs designed for the Z-code or Glulx virtual machines. Versions 1 through 5 were released betw ...

compiler In computing, a compiler is a computer program that translates computer code written in one programming language (the ''source'' language) into another language (the ''target'' language). The name "compiler" is primarily used for programs tha ...

, starting with version 6.30, can produce either

or Glulx story files. A Spanish interactive fiction development system called Superglús also uses Glulx. Despite being a better-adapted virtual machine for modern computing hardware and being just as accessible to developers, Glulx continues to lag behind the Z-machine in popularity, largely due to the comparative rarity of interpreters. The most popular interpreter for Glulx is Andrew Plotkin's Glulxe. Glulxe uses the Glk API for input and output.

File and email extensions

The

MIME Multipurpose Internet Mail Extensions (MIME) is an Internet standard that extends the format of email messages to support text in character sets other than ASCII, as well as attachments of audio, video, images, and application programs. Message ...

type for Glulx is "application/x-glulx". Glulx files have the file extension .ulx, but they are commonly archived in Blorb packages. For Blorb packages containing a Glulx work, accepted file extensions are .gblorb, .glb, .blorb and .blb. The former two extensions are intended to make it easy for interpreters to figure out which type of game is inside the Blorb file.

References

External links

The Glulx specification

Glulx games at "Baf's Guide"

Text adventure game engines Virtual machines {{videogame-software-stub