how to sort crontab in unix

[surekha_4]

I want to know, how can you sort crontab with respect to min, hour and day of month.

[Steve Steel]

Hi

The fields in format x,x,x

Will give a problem but

crontab -l|sort -k 1,1 -k 2,2 -k 3,3

Works


Steve Steel

[Robert-Jan Goossens_1]

Hi,

CRON ENTRIES

minutes hours day Month day_off_week

Hope this helps,
Robert-Jan

[Franky_1]

Hi,

this should work with

crontab -l | sort -k1 -k2 -k3

Regards

Franky

[Muthukumar_5]

min is located in first, hour in second column, and day is on 3rd column on crontab -l

Try as like,

crontab -l | sort -nbk 1,3

It will sort 1 to 3 fields one by one.

-nb are used for optional field separation between the fields.

Regards
Muthu

[Yogeeraj_1]

hi,

this is how my end of crontab looks like:
#*******************************************************************************
# min|hour |day |month|day |script
# | |of mo| |of wk|
#----|-----|-----|-----|-----|--------------------------------------------------
#*******************************************************************************
#*******************************************************************************
# END OF TABLE day0->Sunday day6->Saturday
#*******************************************************************************

one easy way to see it sorted is using SAM->Process Management->Scheduled Cron Jobs->View->sort

regards
Yogeeraj

[surekha_4]

Thanks a lot for all your prompt responses.

I wanted to sort first w.r.t minutes and then w.r.t seconds, and the following got me the desired result.

crontab -l | grep -v ^# | sort -nb -k 2,1,3

...

But i would like to know.. why we are using
-k 2,2 1,1
in this case: crontab -l|sort -k 2,2 -k 1,1 -k 3,3.

Also, i am looking at extracting crontabs for a given timeframe say from 7 am to 8 am.

What i intend to do is to read the sorted crontab into a file and then extract cron-entries from 7am to 8am.
But is there a better method of doing the same?

Do let me know.

Thanks to one and all

[Muthukumar_5]

Sort command will work based upon the key settings.

IF you are going to sort with multiple fields one by one then we have to use multiple keys else,

crontab -l | grep -v ^# | sort -nb -k 2,1,3

it will not give the effect.

IF you are trying to sort as non-order then ( 2 , 1 , 3) then you have to use multiple keys. Else you can as like as -k 1,3 ( to sort from 1 to 3)

In your case it will sort based on 2nd field then 1st then 3rd one.

You can also use as,

crontab -l | grep -v ^# | sort -nb -k 2,2 1,1 3,3

or
crontab -l | grep -v ^# | sort -nb -k 2 -k 1 -k 3

-k --> startpos , end pos

You can give or need not.

To know more about the difference refer the sort man page for -k options. It will give some more effective features / usage on keys

Regarding extraction on time limit, it is good to extract the timelimits on sorted cornjobs with grep command.

It will give the way to do.

Regards
+Muthu+

[surekha_4]

Thanks for your guidance.

I am sorting crontab and then grep cron for the timeframe.

Regards,
Surekha

[Franky_1]

Hi Surekha,

don't forget to assign points ...

Regards

Franky

[surekha_4]

Thanks again to one and all.

Any of the following may be used to sort the crontab:

crontab -l | grep -v ^# | sort -nb -k 2,1,3
or
crontab -l | grep -v ^# | sort -nb -k 2,2 1,1 3,3
or
crontab -l | grep -v ^# | sort -nb -k 2 -k 1 -k 3