Shell Programming and Scripting

So, do you mean
A) Consistently alternate weeks, or
B) certain weeks of the month which could be:-With all of these, you have to consider that there will either be an occasional extra week between runs (case 1 & 2) or occasions where the run is on consecutive weeks (case 3)

If you are after A then I have suggested a solution which you have not replied to. Could you consider that and let me know if I have it right, or if not, why not and I will try to modify my suggestion.

If you are after B then let me know which and I'm sure we can work it out.



Yours faithfully,
Robin
Liverpool/Blackburn
UK

Hi Rabin,

Sorry for delay reply.
below is the output for your program that you have given.--
This is an odd week of the year.
No actions performed.

But this is my simple Requirement.
i have to run a shell script a day in alternate week.
suppose today's date is Wednesday 27-Mar-2013 today will run
and next run date will be on 10-April-2013(Wednesday) after 14days gap.

Here my problem is when i will run on 10-April-2013 ,i have to check last run date (here last run date is 27-Mar-2013) and 14 days gap if it is matched 14 days from current date then run the shell script else give any msg.

about your Point..

i am not checking any even or odd day because i don't need that
2nd it may any day like Monday to Friday (but it should be alternate week from day of run)
3rd First, third and any possible fifth Monday each month ... Not like this.

Please understand my requirement and give me some solution.

Best Regards,
Krupa

If it is every two weeks, regardless of which month it falls into what I discussed in post #3 of this thread. Set the test operator highlighted in read to be -eq if you want to run on the odd weeks to be used and schedule the script for the correct day with cron. If you want it at 3am for instance, you can choose from a cron entry like one of these:-

Code:

0 3 * * 0   /path/biweekly.sh      # Sunday
0 3 * * 1   /path/biweekly.sh      # Monday
0 3 * * 6   /path/biweekly.sh      # Saturday

The others are obvious.

I suppose that you could do it another way and have a reference file.

When you run the script, you could touch the file and therefore set the file time stamp, then with find you could test if it is old enough to run. Something like:-

Code:

#!/bin/ksh


if [ `find /var/my_app -name bi_weekly_flag -mtime +12|wc -l` -eq 0 ]
then
   print "This is too soon after the previous run."
   print "No actions performed."
   exit
fi

# Update reference file and proceed

touch /var/my_app/bi_weekly_flag

blah blah blah.......

Then schedule it to run on the required day each week. You will need to create the file for the first run. You can set a very old date as a timestamp to be sure:

Code:

touch -mt 200001010000 /var/my_app/bi_weekly_flag

I've left the find looking for files older that 12 days (-mtime +12) because if you run the script at the same time, the difference between the time of the touch command running might make it a bit pot-luck.

Do either of these help, or have I still missed the point?



Robin

I appreciated your solution .


find /var/my_app -name bi_weekly_flag -mtime +14|wc -l` -eq 0



Thank you very much.

i have a small doubt about date-
How to get before 15 day’s date(28:Mar:2013 format) from current date.
I tried with below code:-
date +%d:%b:%Y|awk -vFS=":" -vOFS=":" '{$1=$1-30;print}'

it is giving correct result if both dates are coming within a month
problem:-
if before 15 day ‘s date is coming previous month the result is giving –Ve value.

Please send me this important solution.

Best Regards,
Krupa

Well there is something I'm just getting started with. Depending on your release, you may have an option on the date command of --date=STRING

I've done a bit of experimenting and you could do something like:-

Code:

date +%d:%b:%Y --date="today - 15 days"

Is this an option?

If not, some systems respect a time-zone beyond 24 hours.

Code:

#!/bin/ksh
RealTZ="$TZ"

((hoursback=15*24))
((hoursback=$hoursback-$offset))       # Set the offset according to your base timezone against GMT or UTC.

TZ="GMT${hoursback}BST"         # Okay, so I'm British, pick your own variation

date +%d:%b:%Y

TZ="$RealTZ"

This is not available on all systems, AIX is one that is.



Do either of these suggestions help?




Robin

I have changed accordingly as per your suggestion,it is working fine.

Thanks alot

Regards,
Krupa

You are welcome. I'm still learning too and it's good to have a target to experiment with.


Robin