Run Periodic Tasks with vovcrontab

The UNIX utility crontab is used to perform regularly scheduled tasks such as retracing an entire project each night or storing a back-up of the trace every Saturday. vovcrontab is a VOV utility that simplifies the creation of cron rules for a project. Directions are provided in this section.

Usage: voncontrab

vovcrontab: DESCRIPTION:
vovcrontab:     Interface to the UNIX utility crontab.
vovcrontab: 
vovcrontab: USAGE:
vovcrontab:     % vovcrontab [option]
vovcrontab: 
vovcrontab: OPTIONS:
vovcrontab:   -help        -- Get this message
vovcrontab:   -new         -- Install the crontab for this project
vovcrontab:                   Also used to update the scripts/vovdir.csh script.
vovcrontab:   -noautostart -- Do not install autostart script to update
vovcrontab:                   vovdir.csh; the default is to install it.
vovcrontab:   -reinstall   -- Reinstall current crontab for this project
vovcrontab:   -clear       -- Clear the current crontab
vovcrontab:   -show        -- Show the crontab
vovcrontab:   -type <type> -- Specify project type
vovcrontab: 
vovcrontab: NOTE:
vovcrontab:     Please remember to copy
vovcrontab:     $(VOVDIR)/etc/autostart/update_crontab_vovdir.csh
vovcrontab:     into your autostart directory if needed.
vovcrontab:     It is installed by default.

Enable a Project

Enable a project in a shell via:

'vovproject enable <PROJECT>'

Create crontabs

Execute 'vovcrontab -new' to create crontabs.

% vovcrontab -new
vovcrontab: Creating vnc.swd/scripts/cron.csh
vovcrontab: Creating cron table vnc.swd/crontab.lion
no crontab for john
vovcrontab: Installing new crontab.
vovcrontab: Installing updated crontab

This program prepares the scripts $SWD/scripts/cron.csh and $SWD/crontab.hostname.

Display Current crontab Definition

Running vovcrontab -show shows the current crontab definition.

% vovcrontab -show
#### (vovcrontab) START PROJECT vnc ####
#
# ... some lines omitted...
#
# Every hour at 5 minutes before the hour.
55 * * * *  /home/john/vov/vnc.swd/scripts/cron.csh hourly
#
# Every day: at 23:15
15 23 * * *     /home/john/vov/vnc.swd/scripts/cron.csh daily
# 
# Every week: on Saturday at 7:00am
0  7  * * 6     /home/john/vov/vnc.swd/scripts/cron.csh weekly
#
# Every month: on the 1st at 3:00am
0  3  1 * *     /home/john/vov/vnc.swd/scripts/cron.csh monthly
#### (vovcrontab) END PROJECT vnc ####

Customize the crontab

The crontab can be customized by editing either $SWD/crontab.hostname or $SWD/scripts/cron.csh. Afterwards,

vovcrontab
                    -reinstall

will need to be run to take the modifications into consideration.

% vovcrontab -reinstall
vovcrontab: vnc.swd/scripts/cron.csh  exists already.
vovcrontab: vnc.swd/crontab.lion exists already.
vovcrontab: Installing new crontab.
vovcrontab: Installing updated crontab

Delete the Current crontab Definition

To delete current crontab definitions, use:

'vovcrontab -clear'
vovcrontab: vnc.swd/scripts/cron.csh  exists already.
vovcrontab: vnc.swd/crontab.lion exists already.
vovcrontab: Removing the crontab

Complete the Cleanup

To complete the cleanup, remove the crontab.HOSTNAME file in the SWD directory of the project.

% rm crontab.lion