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Mcron
Computer languages Scheme  +
Documentation note A full discussion of the design and philosophy of mcron can be found [http://www.gnu.org/software/mcron/design.html online]. The [https://www.gnu.org/software/mcron/manual/ manual] needs to be updated…
Full description The mcron program represents a complete reThe mcron program represents a complete re-think of the cron concept originally found in the Berkeley and AT&T unices, and subsequently rationalized by Paul Vixie. The original idea was to have a daemon that wakes up every minute, scans a set of files under a special directory, and determines from those files if any shell commands should be executed in this minute. It'is a 100% Vixie cron replacement written in pure [[Guile]]. As well as accepting traditional crontabs, it also accepts configuration files written in [[Guile|Scheme]] for infinite flexibility in specifying when jobs should run (it could take the system load into account, for example). The new idea is to read the required command instructions, work out which command needs to be executed next, and then sleep until the inferred time has arrived. On waking the commands are run, and the time of the next command is computed. Furthermore, the specifications are written in scheme, allowing at the same time simple command execution instructions and very much more flexible ones to be composed than the original Vixie format. This has several useful advantages over the original idea. (Changes to user crontabs are signalled directly to mcron by the crontab program; cron must still scan the ''/etc/crontab'' file once every minute, although use of this file is highly discouraged and this behaviour can be turned off). * Does not consume CPU resources when not needed. Many cron daemons only run jobs once an hour, or even just once a day. * Can easily allow for finer time-points to be specified, i.e. seconds. In principle this could be extended to microseconds, but this is not implemented. * Times can be more or less regular. For example, a job that runs every 17 hours can be specified, or a job that runs on the first Sunday of every month. * Times can be dynamic. Arbitrary [[Guile]] (scheme) code can be provided to compute the next time that a command needs to be run. This could, for example, take the system load into consideration. * Each user looks after his own files in his own directory. He can use more than one to break up complicated cron specifications. * Each user can run his own daemon. This removes the need for suid programs to manipulate the crontabs, and eliminates many security concerns that surround all existing cron programs. * The user can obtain an advance schedule of all the jobs that are due to run.edule of all the jobs that are due to run.
GNU package identifier mcron  +
Homepage URL https://www.gnu.org/software/mcron/  +
Interface command-line  + , daemon  +
Is GNU true  +
Keywords system administration  + , scheduling  + , scheme  + , cron  + , crontab  + , Vixie  +
Last review by Genium +
Last review date 11 May 2014  +
License GPLv3orlater +
License note Copyright (C) 2003, 2005, 2006, 2012, 2014 Dale Mellor  +
License verified by genium  +
License verified date 11 May 2014  +
Name GNU mcron  +
Real name Dale Mellor  +
Related projects Cron + , Cronwrap + , Cronolog +
Resource URL mailto:bug-mcron@gnu.org  + , mailto:help-mcron@gnu.org  + , mailto:info-mcron@gnu.org  + , http://git.savannah.gnu.org/cgit/mcron.git  +
Resource audience Bug Tracking  + , Support  + , Help  + , Developer  +
Resource kind E-mail  + , VCS Repository Webview  +
Revisionid 22,814  +
Revisiontimestamp 10 October 2014 15:08:47  +
Revisionuser User:Mtjm +
Role Maintainer  +
Short description Vixie cron replacement  +
Submitted by Database conversion +
Submitted date 1 April 2011  +
User level none  +
VCS checkout command git clone git://git.savannah.gnu.org/mcron.git  +
Version date 25 May 2014  +
Version download https://ftp.gnu.org/gnu/mcron/mcron-1.0.8.tar.gz  +
Version identifier 1.0.8  +
Version status stable  +
Has queryThis property is a special property in this wiki. Mcron + , Mcron + , Mcron + , Mcron + , Mcron + , Mcron + , Mcron + , Mcron + , Mcron +
Modification dateThis property is a special property in this wiki. 25 November 2014 17:44:15  +
Page has default formThis property is a special property in this wiki. Entry  +
Has subobjectThis property is a special property in this wiki. Mcron + , Mcron + , Mcron + , Mcron + , Mcron + , Mcron + , Mcron +
EmailThis property is a special property in this wiki. dale_mellor@users.sourceforge.net  +
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