The problem with using DOW is that there are 7 days - plus sunday may not be day 0 depending on your locale. 7 does not divide evenly by 3.
If you literally want every third day try setting up a daily cron entry that checks for "thirdness"
is the number of days since Jan 1 1970. # of days % 3 == 0 means it is a day divisible evenly by three.
This trick works for any weird number of days that don't track well as a DOW or a fixed day in the month.
Last edited by jim mcnamara; 08-18-2009 at 08:21 AM..
hello there,
i'm learning about task scheduling with cron and all seems hyper exciting, yeppie. But there is a prob:
assume i have a script that needed to be executed at 7am everyday. I could do:
vi mycron
00 7 * * * echo hi mother, i wanna be a script daddy.
:wq
crontab mycron
how... (4 Replies)
Is there a way in AIX to schedule a script to run bi-weekly through cron?
I have a script that needs to run every other Wednesday, and this is what I thought I had to enter in the crontab file:
00 08 * * 3/2 /home/user/user.script
It didn't like that. It reports a syntax error. I'm almost... (5 Replies)
I would like to setup a cron job to run a command from another directory.
What is the best way to do this?
The cron file is in a directory and the script I want it to run is in another directory.
I tried doing this in the cron file:
/location/of/command/run.sh
But that did not work.... (2 Replies)
Hello, is it possible to schedule cron jobs using business days instead of calendar days? I need to run several jobs on first and third business days of the month. I currently have this cron-tab entry which runs every week day at 5 AM. I need to schedule the same job on the 3rd Business day of the... (8 Replies)
Hi Everybody,
I want to run a script at every 5 seconds. I know how to run it every 5 minutes, is there any possibility to run a script at 5 seconds interval.
Regards,
Mastan (3 Replies)
Hi,
I created this cron job for asterisk to send sms daily to a number
#!/bin/sh
#custom mod - send sms once a day, at 07:00.
CRON_PATH="/etc/asterisk/gw/crontabs_root";
if ! grep 'gsm send sms' $CRON_PATH > /dev/null 2>&1 ;then
echo "* 7 * * * asterisk -rx 'gsm send sms 1 7666... (4 Replies)
Discussion started by: jazzyzha
4 Replies
LEARN ABOUT CENTOS
cal
CAL(1) User Commands CAL(1)NAME
cal - display a calendar
SYNOPSIS
cal [options] [[[day] month] year]
DESCRIPTION
cal displays a simple calendar. If no arguments are specified, the current month is displayed.
OPTIONS -1, --one
Display single month output. (This is the default.)
-3, --three
Display prev/current/next month output.
-s, --sunday
Display Sunday as the first day of the week.
-m, --monday
Display Monday as the first day of the week.
-j, --julian
Display Julian dates (days one-based, numbered from January 1).
-y, --year
Display a calendar for the current year.
-V, --version
Display version information and exit.
-h, --help
Display help screen and exit.
PARAMETERS
A single parameter specifies the year (1 - 9999) to be displayed; note the year must be fully specified: cal 89 will not display a calendar
for 1989.
Two parameters denote the month (1 - 12) and year.
Three parameters denote the day (1-31), month and year, and the day will be highlighted if the calendar is displayed on a terminal. If no
parameters are specified, the current month's calendar is displayed.
A year starts on Jan 1. The first day of the week is determined by the locale.
The Gregorian Reformation is assumed to have occurred in 1752 on the 3rd of September. By this time, most countries had recognized the ref-
ormation (although a few did not recognize it until the early 1900's). Ten days following that date were eliminated by the reformation, so
the calendar for that month is a bit unusual.
HISTORY
A cal command appeared in Version 6 AT&T UNIX.
AVAILABILITY
The cal command is part of the util-linux package and is available from ftp://ftp.kernel.org/pub/linux/utils/util-linux/.
util-linux June 2011 CAL(1)