xautolock-2.1: description + notes
PURPOSE ======= Xautolock monitors console activity under the X window system, and fires up a program of your choice if nothing happens during a user configurable period of time. You can use this to automatically start up a screen locker in case you tend to forget to do so manually before having a coffee break. Xautolock will typically be used to lock the screen but it really doesn't care what program you make it start. The only real assumption made by xautolock is that a new countdown starts as soon as the locker exits. HOW TO USE IT ============= Just read the man page, it's really simple. If you're on VMS, you should also check out the VMS.notes file. HOW IT WORKS ============ If xautolock has been compiled to support either the Xidle, or the MIT ScreenSaver extensions (or both), it first tries to find out whether the X server also supports one of them. If it does, xautolock will periodically call it to determine the amount of time elapsed since the last input event, and will then base its actions upon that. In the absence of both extensions, xautolock starts by traversing the window tree, selecting SubstructureNotify on all windows and adding each window to a temporary list. About +- 30 seconds later, it scans this list, asking for KeyPress events. However, it takes care to interfere as little as possible with the event propagation mechanism. This is the reason for the delay between the moment xautolock learns about a new window (and consequently asks for SubstructureNotify events) and the moment it asks for KeyPress events. Whenever a new window is created by an application, a similar process takes place. In contradiction to what many people believe, this scheme does not cause a noticeable overhead. In addition, xautolock periodically issues a QueryPointer request in order to find out whether the pointer has moved and implement the "corners" feature as decribed in the man page. If nothing happens within a user-specified period of time, xautolock will fire up a program which is supposed to lock the screen. While this program is running, xautolock itself remains on the look-out for user interaction. KNOWN BUGS ========== Important notice: the first two bugs listed here are only present in case xautolock has been compiled with support for neither the Xidle nor the MIT ScreenSaver extensions, or in case the X server being used does not support them. They make up a good reason to get one of these extensions installed. 1. If, when creating a window, an application waits for more than 30 seconds before calling selecting KeyPress events on non-leaf windows, xautolock may interfere with the event propagation mechanism. This effect is theoretical and has never been observed in real life. 2. Xautolock can not properly handle the secure keyboard mode of xterm, since that will prevent any other process, including xautolock, from noticing the keyboard events aimed at the xterm. Consequently, xautolock sometimes will think that there is no keyboard activity while in reality there is. 3. Under some configurations, xautolock fails to exit upon logout. This problem can occur (but does not always do so) under the following combined circumstances: + Xautolock is started in background from within a .xinitrc. + Your are trusting your windowmanager to kill all X processes when quitting (which, by the way, is not a good idea). One well known source of problems in this area consists of olwm and its look-alikes. + The .xinitrc contains a "wait" statement to make it collect all background processes upon logout. The simplest workround for this problem is to start xautolock from within a subshell. I.e. use this: ( xautolock & ) On Solaris an alternative solution (which basically works in exactly the same way) is to use this: toolwait xautolock 4. The -disable, -enable, -toggle, -exit, -locknow, -unlocknow, and -restart options depend on access to the X server to do their work. This implies that they will be suspended in case some other application has grabbed the server all for itself. 5. Xautolock does not check whether the screen locker specified actually is available. 6. The xautolock resources have a dummy resource classes. If you can find others, please notify eyckmans@imec.be. Note that, while I still scan most X related newsgroups, I do not actually read them on a regular basis anymore, as X no longer is a part of my job. I do still actively support xautolock on a daily basis, though. Hence you are much more likely to get quick help if you contact me directly. WARNING ======= It looks like there is a bug in the event management code of some X servers (amongst which both X11R4 and X11R5 on older versions of SunOS). If you are using version 1.7 of xautolock (previously known as patchlevel 7), it is best to reset the server before switching to version 1.8 or later. If you fail to do so, an old version 1.7 bug may still show up. (Some keyboard events were being hijacked by version 1.7 of ================= The contrib directory may contain various patches that have been contributed over time. If a patch is in there, I have for some reason or another decided not to include it in xautolock proper, but still consider it to be sufficiently usefull to other people in order to add it to the distribution. Note that the contents of the contrib directory are *not* part of xautolock. Each of the contributions lives under its own copyright. In version 2.1 of xautolock, the contrib directory is empty, since due to a lack of time I did not feel like porting the stuff that used to be in there to the 2.x versions. Maybe it'll be back in 2.2 or so. COPYRIGHT ========= Copyright 1990, 1992-1999, 2001-2002 by Stefan De Troch and Michel Eyckmans. Versions 2.0 and above of xautolock are available under version 2 of the GNU GPL. Earlier versions are available under other conditions. For more information, see the License file. AUTHORS ======= Xautolock was conceived, written, and performed by: Michel Eyckmans (MCE) eyckmans@imec.be Stefan De Troch stefan@specs.philips.com Please send queries for help, feature suggestions, bug reports, etc. to eyckmans@imec.be only. xautolock, particularly when using tvtwm). ACKNOWLEDGEMENTS ================ Special thanks to: Kris Croes croes@imec.be And the many people who submitted bug reports, patches, suggestions, kudos, etc. No thanks to a certain commercial X server provider who volunteered to beta test version 1.9 on many, *many* platforms but didn't live up to it. Also our apologies to the candidate beta testers who were not retained because of this candidate.CONTRIB DIRECTORY
To auto-install this package, go back and click on the respective install icon.