Today is Friday, October 3, 2014 3:58 AM
I want to schedule a cronjob like that to run it at the following dates:
So every 2 weeks , on Saturday, at 8 o'clock.
0 8 * * 6 test $((10#$(date +\%W)\%2)) -eq 1 && yourCommand
date +%W: week number of year with Monday as first day of week, today week 39
10#$(date +%W): conver the date +W to decimal number and avoid shell base parsing confusion
$((39%2)): modulo operation: result is 0 (even week number) or 1 (odd week number), this week result is 1, next week 0
test 1 -eq 1: arithmetic test (equal), in this case result is boolean true
&& yourCommand: Boolean AND: run yourCommand only if result of previous command was boolean true
Note that the year can get two odd weeks: 53 (this year) and 1 (next year)
What you've shown is "every week". Then the code is:
0 8 * * 6
Are you sure you need to run it every two weeks?
0 8 * * 6 expr `date +\%s` / 604800 \% 2 >/dev/null || yourCommand
