John Heidemann / Software / Xcron-Lcron

Xcron is an implementation of cron by Geoff Kuenning. Notable features about xcron are a careful attention to security constraints, support for a different (and somewhat easier-to-use) crontab format, and catch-up support for jobs that should have run but didn’t because the machine was off or suspended. For more details about xcron, see DOC or Geoff’s paper (tech report UCLA-CSD-990044).

Lcron is a small set of extensions to xcron that support location- and event-triggered actions. Location is primarily determined by network connectivity, events are things like current power status (A/C or battery). Applications include:

Lcron is described in a paper by John Heidemann and Dhaval Shah.

For more details about xcron or lcron, please see the man pages in the distribution.

A beta release of xcron is available here. Although versions of this software have been in use for more than four years, this code may contain bugs and has limited maintenance.

Xcron should run on any variant of Unix. The lcron extensions should also be portable, but the automated installation procedure for lcron is not portable, and small OS-specific may be required to trigger cron on location changes. Lcron is regularly used on RedHat Linux and should be installable by hand on other platforms with modest effort (by someone who understands Makefiles and scripts). (See also README.lcron.)

Download xcron-20070605: source code (tar.gz),

(Download earlier snapshots: 20000417, 20000413, 19990805.)

Known bugs

20000413: no known functionality bugs.

Missing features: GNU autoconf support would be nice, parts of the lcron installation are RedHat-Linux specific. The Redhat RPMs install xcron in a funny place.

Copyright © 2000-2003 by John Heidemann