From: Rob Biedenharn <Rob@...>
Date: 2010-12-15T01:48:48+09:00
Subject: Re: Grep a string


On Dec 14, 2010, at 11:20 AM, Rajesh M. wrote:

> Peter Vandenabeele wrote in post #968289:
>> On Tue, Dec 14, 2010 at 2:32 PM, Rajesh M. <munikur@gmail.com> wrote:
>>> 0 10 * * 0 sync; sync; reboot <---- regex should look for only sync;
>>> For example in another system if the crontab entry is like:
>>> 0 6 * * 0 shutdown -y -g0 -i6
>>> regular expression should only look for the string after digitals  
>>> 0 6 *
>>> * 0, here it should look for shutdown -y -g0 -i6
>>
>> If on the commandline, 'cut' may be useful.
>>
>> $ cat crontab | egrep '^[0-9\*]'
>> 17 *  * * *  root    cd / && run-parts --report /etc/cron.hourly
>> 25 6  * * *  root  test -x /usr/sbin/anacron || ( cd / && run-parts
>> --report /etc/cron.daily )
>> 47 6  * * 7  root  test -x /usr/sbin/anacron || ( cd / && run-parts
>> --report /etc/cron.weekly )
>> 52 6  1 * *  root  test -x /usr/sbin/anacron || ( cd / && run-parts
>> --report /etc/cron.monthly )
>>
>> $ cat crontab | egrep '^[0-9\*]' | cut -f3-
>> root    cd / && run-parts --report /etc/cron.hourly
>> root  test -x /usr/sbin/anacron || ( cd / && run-parts --report
>> /etc/cron.daily )
>> root  test -x /usr/sbin/anacron || ( cd / && run-parts --report
>> /etc/cron.weekly )
>> root  test -x /usr/sbin/anacron || ( cd / && run-parts --report
>> /etc/cron.monthly )
>>
>> 'cut' splits by default on <TAB> and there seem to be exactly 2 TAB's
>> before the 'root'
>> part (you can use $ od -ax crontab  to check that in detail).
>>
>> HTH,
>>
>> Peter
>
>
>
> cat /tmp/cron.list | egrep '^[0-9\*]'
> 00 01 * * 0 (sync ; sync ; sync ; /sbin/reboot)
> 00 18 * * 6 (sync; sync; sync; /sbin/reboot)
>
>
> Not sure it is still getting digits, what am doing wrong here?
>
> -- 
> Posted via http://www.ruby-forum.com/.
>


cat /tmp/cron.list | ruby -nle 'next if $_ =~ /^\s*#/; fields =  
$_.split(" ",6); puts fields.inspect;'

Or:

cat /tmp/cron.list | ruby -nle 'next unless $_ =~ /sync|reb|shut/;  
fields = $_.split(" ",6); puts fields.inspect;'

Can you work with that?  If not, then why do you keep asking on a Ruby  
list?

-Rob

Rob Biedenharn		
Rob@AgileConsultingLLC.com	http://AgileConsultingLLC.com/
rab@GaslightSoftware.com		http://GaslightSoftware.com/