computing Computing is any goal-oriented activity requiring, benefiting from, or creating computing machinery. It includes the study and experimentation of algorithmic processes, and development of both hardware and software. Computing has scientific, ...

, XFixes is an

X Window System The X Window System (X11, or simply X) is a windowing system for bitmap displays, common on Unix-like operating systems. X provides the basic framework for a GUI environment: drawing and moving windows on the display device and interacting ...

extension which makes useful additions to the X11 protocol. It was started in 2003 by

Keith Packard Keith Packard (born April 16, 1963) is a software developer, best known for his work on the X Window System. Packard is responsible for many X extensions and technical papers on X. He has been heavily involved in the development of X since the l ...

. It first appeared in the

KDrive X.Org Server is the Free and open-source software, free and open-source implementation of the X Window System display server stewarded by the X.Org Foundation. Implementations of the client-side X Window System protocol exist in the form of ' ...

X server and later in X.Org Server version 6.8.0. The extension implements a collection of unrelated additions to the protocol. The theme of the collection is small additions to remove important defects in the protocol that can't be worked around using the pure X11 protocol. The point of implementing these additions in an extension is to leave the core server code, and a server that does not include the XFixes extension, implementing the original pure X11 protocol. However, as the additions are designed in a backward compatible way, there is no practical reason for a server not to implement them. The client and server can always negotiate down to the additions that both understand.

Version history

*Version 1 of the extension included Save Set processing changes (to make embedding applications more reliable), selection notification events (add events sent when selection ownership is asserted) and cursor tracking (requests allowing the image to be tracked reliably). *Version 2 of the extension adds region objects and cursor names. *Version 3 allows existing region objects to be enlarged. *Version 4 allows the mouse cursor to be hidden over specific windows. *Version 5 introduces pointer barriers, which allows using easy-to-reach locations (according to

Fitts's Law Fitts's law (often cited as Fitts' law) is a predictive model of human movement primarily used in human–computer interaction and ergonomics. The law predicts that the time required to rapidly move to a target area is a function of the ratio betw ...

) even in

multi-monitor Multi-monitor, also called multi-display and multi-head, is the use of multiple physical display devices, such as monitors, televisions, and projectors, in order to increase the area available for computer programs running on a single compute ...

configurations.

Controversy

XFixes was a source of controversy when Packard committed the extension to the

XFree86 XFree86 is an implementation of the X Window System. It was originally written for Unix-like operating systems on IBM PC compatibles and was available for many other operating systems and platforms. It is free and open source software under the XF ...

project hours before the feature freeze window for XFree86 4.3.0 began in December 2002 without prior approval of the XFree86's Core Team (a

cathedral A cathedral is a church that contains the ''cathedra'' () of a bishop, thus serving as the central church of a diocese, conference, or episcopate. Churches with the function of "cathedral" are usually specific to those Christian denominatio ...

-style group that were allowed to commit changes to the project, of which Packard was a member). Packard was stripped of his commit rights as a result (but remained in the project's Core Team until March 2003) and the extension was backed out six weeks later.CVS commit: Finish removing XFIXES
, By David Dawes, 12 Jan 2003

References

External links

X Fixes extension
(freedesktop.org)
The X Fixes Extension, Latest Official Specifications
X Window extensions {{graphics-software-stub