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Deleting specific lines in a file

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# 1  
Old 08-04-2011
Deleting specific lines in a file
Hello,

I have a file filled with dates, such as:

Code:
04-08-2011 message
04-08-2011 message
03-08-2011 message
01-08-2011 message
31-07-2011 message
24-07-2011 message
15-07-2011 message
13-12-2008 message
26-11-2007 message

And I want to delete those lines whose date is older than 10 days.

Someway like "find ... -mtime +10 rm{}..." but relating to the lines in a file...

Ah, it should be under "AIX"

Thank you
Last edited by asanchez; 08-04-2011 at 06:56 AM..
# 2  
Old 08-04-2011
Code:
perl '-MPOSIX qw(strftime)' -nle'BEGIN {
  $dt = strftime "%Y%m%d", localtime time - 86400 * shift;
  }
 (join "", (split /[\s-]+/)[2,1,0]) >= $dt and print   
  ' 10 infile


The above command will print the remaining lines on the standard output.
If you want to modify your existing file:

Code:
perl -i.bck '-MPOSIX qw(strftime)' -nle'BEGIN {
  $dt = strftime "%Y%m%d", localtime time - 86400 * shift;
  }
 (join "", (split /[\s-]+/)[2,1,0]) >= $dt and print   
  ' 10 infile

# 3  
Old 08-04-2011
Nice!

But it does not remove the lines, it just print them.
Is it possible to do it in ksh?

Thank you
# 4  
Old 08-04-2011
I've updated my previous post.
# 5  
Old 08-04-2011
Okay,

thank you. I would like to have in ksh but it's a good workaround for the moment in perl.
# 6  
Old 08-04-2011
You could do it in pure Korn Shell easily if you have a recent version of ksh93 that support the following syntax:

Code:
ksh-JM 93u 2011-02-08$ print -f  '%(%Y%m%d)T\n' '10 days ago'
20110725


Alternatively you could use the datecalc script by Perderabo.
Last edited by radoulov; 08-04-2011 at 09:07 AM..
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