Twm
Encyclopedia
In computing
, twm (originally Tom's Window Manager, then Tab Window Manager and now Timeless Windows Manager) is the standard window manager
for the X Window System
, version X11R4 onwards. It is a re-parenting window manager
that provides title bars, shaped windows and icon management, and is extensively configurable.
twm was a breakthrough achievement in its time, but has been largely superseded by other window managers. twm made a strong impact on the development of X window managers. Many others, such as vtwm
, tvtwm
, CTWM
, FVWM
and their derivatives, were built on its code
, while many others used concepts pioneered by it.
A small but dedicated minority of users favor twm for its simplicity, customizability, and light weight—partly due to being written in C
directly against Xlib
rather than based on a widget toolkit
. twm is still standard with the X.Org
reference implementation
and is available as part of many X distributions. The Knoppix
live CD will resort to twm if the computer it is running on lacks the RAM for a more sophisticated window manager.
twm was created by Tom LaStrange. It is currently maintained in X.Org by Eeri Kask.
s of the present day, which tend to work similarly to the Apple Macintosh or the various versions of Microsoft Windows
. New users often find twm difficult to understand without reading the manual page.
In the default configuration of twm, the title bar has two buttons:
There is no title bar button to close a window. A left click on the desktop brings up a menu, which includes an option to delete (close) a window.
A left click on the title bar brings the window to the top of the window stack; a middle click moves the window; a right click sends the window to the bottom of the window stack.
Window focus
follows the mouse pointer (point-to-focus), rather than being on whichever window was clicked last (click-to-focus).
When a new window is created, a 3×3 grid is displayed following the mouse pointer, waiting for the user to click where the window should appear — left-click to appear in that position with that size, middle-click to resize the window before its creation, right-click to appear at that position but long enough vertically to reach the bottom of the screen.
Note that any of the above may be changed with appropriate changes to the configuration file.
Menu config file: /etc/X11/twm/system.twmrc
: "I sat down at my monochrome Sun 3/50 and typed vi twm.c and then opened the X11 documentation. twm was my first X program. About six months later, I convinced my manager to let me send a copy to the comp.windows.x newsgroup." A version for X11R1 was published on the Usenet
newsgroup comp.unix.sources on June 13, 1988.
Nine months later, Jim Fulton of the MIT X Consortium approached Tom and asked that he turn over the maintenance of the code to the X Consortium. Fulton made it compliant with the then-new Inter-Client Communication Conventions Manual
and Keith Packard
added support for shaped title bars. Subsequently, twm was released as the standard sample window manager for X11R4, replacing uwm
.
twm originally stood for Tom's Window Manager. When the X Consortium took over its maintenance, and several other people had contributed substantially, its name was changed to Tab Window Manager. The vtwm.gamma man page says: "To save Tom LaStrange from being blamed for any of the massive numbers of changes that have been done to twm since he gave up control of it, the name 'twm' now stands for 'Tab Window Manager'."
According to Fulton, the word "tab" was picked because it conveniently started with 'T' and put the emphasis on the squeezing feature window title bars, which made them look like folders with tabs.
and Dave Sternlicht, all three at the X Consortium at the time, Steve Pitschke, then at Stardent Computer, and Dave Payne, then at Apple Computer
.
Eeri Kask is presently maintaining twm to work well with modern X.Org capabilities, such as XRender
and transparency.
Computing
Computing is usually defined as the activity of using and improving computer hardware and software. It is the computer-specific part of information technology...
, twm (originally Tom's Window Manager, then Tab Window Manager and now Timeless Windows Manager) is the standard window manager
X window manager
An X window manager is a window manager which runs on top of the X Window System, a windowing system mainly used on Unix-like systems.Unlike the Mac OS and Microsoft Windows platforms which have historically provided a vendor-controlled, fixed set of ways to control how windows and panes display...
for the X Window System
X Window System
The X window system is a computer software system and network protocol that provides a basis for graphical user interfaces and rich input device capability for networked computers...
, version X11R4 onwards. It is a re-parenting window manager
Re-parenting window manager
A stacking window manager is a window manager that draws all windows in a specific order, allowing them to overlap, using a technique called painter's algorithm...
that provides title bars, shaped windows and icon management, and is extensively configurable.
twm was a breakthrough achievement in its time, but has been largely superseded by other window managers. twm made a strong impact on the development of X window managers. Many others, such as vtwm
Vtwm
Vtwm is an X window manager that was developed from the twm codebase. The first release was in 1990, and it is very much an "old school" window manager. It added features like xpm icons, autoraising of windows, and a virtual desktop; the latter feature is from where the program takes its name...
, tvtwm
Tvtwm
tvtwm is an X window manager derived from twm to which it adds the virtual desktop feature from swm. All of these window managers were originally written by Tom LaStrange...
, CTWM
CTWM
In Unix computing, CTWM is a stacking window manager for the X Window System in the twm family of window managers...
, FVWM
FVWM
The F Virtual Window Manager is a virtual window manager for the X Window System. Originally a twm derivative, FVWM has evolved into a powerful and highly configurable environment for Unix-like systems.- History:...
and their derivatives, were built on its code
Source code
In computer science, source code is text written using the format and syntax of the programming language that it is being written in. Such a language is specially designed to facilitate the work of computer programmers, who specify the actions to be performed by a computer mostly by writing source...
, while many others used concepts pioneered by it.
A small but dedicated minority of users favor twm for its simplicity, customizability, and light weight—partly due to being written in C
C (programming language)
C is a general-purpose computer programming language developed between 1969 and 1973 by Dennis Ritchie at the Bell Telephone Laboratories for use with the Unix operating system....
directly against Xlib
Xlib
Xlib is an X Window System protocol client library written in the C programming language. It contains functions for interacting with an X server. These functions allow programmers to write programs without knowing the details of the protocol...
rather than based on a widget toolkit
Widget toolkit
In computing, a widget toolkit, widget library, or GUI toolkit is a set of widgets for use in designing applications with graphical user interfaces...
. twm is still standard with the X.Org
X.Org
X.Org refers to several things related to the X Window System:* X.Org, the organisation in charge of X standards from 1999 * The X.Org Foundation, a community-based foundation which took over X stewardship in 2004...
reference implementation
Reference implementation
In the software development process, a reference implementation is the standard from which all other implementations, with their attendant customizations, are measured, and to which all improvements are added...
and is available as part of many X distributions. The Knoppix
Knoppix
Knoppix, or KNOPPIX , is an operating system based on Debian designed to be run directly from a CD / DVD or a USB key , one of the first of its kind for any operating system. Knoppix was developed by Linux consultant Klaus Knopper. When starting a program, it is loaded from the removable medium...
live CD will resort to twm if the computer it is running on lacks the RAM for a more sophisticated window manager.
twm was created by Tom LaStrange. It is currently maintained in X.Org by Eeri Kask.
Using twm
twm's interface is very different from that of common X window managers and desktop environmentDesktop environment
In graphical computing, a desktop environment commonly refers to a style of graphical user interface derived from the desktop metaphor that is seen on most modern personal computers. These GUIs help the user in easily accessing, configuring, and modifying many important and frequently accessed...
s of the present day, which tend to work similarly to the Apple Macintosh or the various versions of Microsoft Windows
Microsoft Windows
Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
. New users often find twm difficult to understand without reading the manual page.
In the default configuration of twm, the title bar has two buttons:
- Resize button (nested squares): the user clicks here, drags the mouse pointer to the edge to be moved, then releases when the window is the desired size.
- Iconify button (circle): reduces the window to an icon.
There is no title bar button to close a window. A left click on the desktop brings up a menu, which includes an option to delete (close) a window.
A left click on the title bar brings the window to the top of the window stack; a middle click moves the window; a right click sends the window to the bottom of the window stack.
Window focus
Focus (computing)
In computing, the focus indicates the component of the graphical user interface which is currently selected to receive input. Text entered at the keyboard or pasted from a clipboard is sent to the component which currently has the focus. Moving the focus away from a specific user interface element...
follows the mouse pointer (point-to-focus), rather than being on whichever window was clicked last (click-to-focus).
When a new window is created, a 3×3 grid is displayed following the mouse pointer, waiting for the user to click where the window should appear — left-click to appear in that position with that size, middle-click to resize the window before its creation, right-click to appear at that position but long enough vertically to reach the bottom of the screen.
Note that any of the above may be changed with appropriate changes to the configuration file.
Menu config file: /etc/X11/twm/system.twmrc
History
twm was written by Tom LaStrange, then at Evans and Sutherland, starting in 1987, owing to frustration with the then-standard uwmUltrix Window Manager
The Ultrix Window Manager was the standard window manager for the X Window System from X11R1 through X11R3 releases. In fact, it was the only X11-compatible window manager as of X11R1.- History :...
: "I sat down at my monochrome Sun 3/50 and typed vi twm.c and then opened the X11 documentation. twm was my first X program. About six months later, I convinced my manager to let me send a copy to the comp.windows.x newsgroup." A version for X11R1 was published on the Usenet
Usenet
Usenet is a worldwide distributed Internet discussion system. It developed from the general purpose UUCP architecture of the same name.Duke University graduate students Tom Truscott and Jim Ellis conceived the idea in 1979 and it was established in 1980...
newsgroup comp.unix.sources on June 13, 1988.
Nine months later, Jim Fulton of the MIT X Consortium approached Tom and asked that he turn over the maintenance of the code to the X Consortium. Fulton made it compliant with the then-new Inter-Client Communication Conventions Manual
Inter-Client Communication Conventions Manual
In computing, the Inter-Client Communication Conventions Manual is a standard for interoperability between X Window System clients of the same X server. It is primarily used for communication between normal clients and the window manager. It was designed by David S. H. Rosenthal of the MIT X...
and Keith Packard
Keith Packard
Keith Packard 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...
added support for shaped title bars. Subsequently, twm was released as the standard sample window manager for X11R4, replacing uwm
Ultrix Window Manager
The Ultrix Window Manager was the standard window manager for the X Window System from X11R1 through X11R3 releases. In fact, it was the only X11-compatible window manager as of X11R1.- History :...
.
twm originally stood for Tom's Window Manager. When the X Consortium took over its maintenance, and several other people had contributed substantially, its name was changed to Tab Window Manager. The vtwm.gamma man page says: "To save Tom LaStrange from being blamed for any of the massive numbers of changes that have been done to twm since he gave up control of it, the name 'twm' now stands for 'Tab Window Manager'."
According to Fulton, the word "tab" was picked because it conveniently started with 'T' and put the emphasis on the squeezing feature window title bars, which made them look like folders with tabs.
Authors
twm was originally written by Tom LaStrange. Later substantial contributors include Jim Fulton, Keith PackardKeith Packard
Keith Packard 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...
and Dave Sternlicht, all three at the X Consortium at the time, Steve Pitschke, then at Stardent Computer, and Dave Payne, then at Apple Computer
Apple Computer
Apple Inc. is an American multinational corporation that designs and markets consumer electronics, computer software, and personal computers. The company's best-known hardware products include the Macintosh line of computers, the iPod, the iPhone and the iPad...
.
Eeri Kask is presently maintaining twm to work well with modern X.Org capabilities, such as XRender
XRender
The X Rendering Extension is an X Window System extension to implement Porter-Duff image compositing in the X server, to allow efficient display of transparent images.- History :...
and transparency.
External links
- Tab Window Manager (xwinman)
- [ftp://ftp.isc.org/usenet/comp.sources.unix/volume15/twm/ Original comp.unix.sources posting]
- An Overview of twm (Tom's Window Manager) (PDFPortable Document FormatPortable Document Format is an open standard for document exchange. This file format, created by Adobe Systems in 1993, is used for representing documents in a manner independent of application software, hardware, and operating systems....
) — Tom LaStrange, Xhibition '89 Conference Proceedings — concerning pre-ICCCM versions of twm - From the Desktop: Tom LaStrange Speaks!: Talking with a Man Named Tom (Brian Proffitt, LinuxPlanet, Tuesday 6 February 2001)