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Reading from a dynamically decided line number

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# 1  
Old 06-27-2013
Reading from a dynamically decided line number
Hi All,

We get a file from our client for processing everyday. We have to start reading the file from the line after the line that says "version=".
My idea was to grep and find the line number(say 'n') of the line with "version=" and start reading from the (n+1)th line. Can anyone please guide me on how to achieve this
# 2  
Old 06-27-2013
Quote:
Originally Posted by jerome_rajan
Hi All,

We get a file from our client for processing everyday. We have to start reading the file from the line after the line that says "version=".
My idea was to grep and find the line number(say 'n') of the line with "version=" and start reading from the (n+1)th line. Can anyone please guide me on how to achieve this
You are on the right track.
First grep version= and set line number to variable called n.
Then use this variable and use awk for printing lines whose line number is more than n
Use NR for line number.

Regards,

pamu
# 3  
Old 06-27-2013
just did this


Code:
$n=`grep -n "Version=" filename | cut -d ":" -f1`
$echo $n
10681
$awk 'NR>$n' filename
awk: 0602-562 Field$() is not correct

Any idea why I got that error?
# 4  
Old 06-27-2013
Quote:
Originally Posted by jerome_rajan
just did this


Code:
$n=`grep -n "Version=" filename | cut -d ":" -f1`
$echo $n
10681
$awk 'NR>$n' filename
awk: 0602-562 Field$() is not correct

Any idea why I got that error?
Use -v in awk for using shell variable into awk.
This User Gave Thanks to pamu For This Post:
jerome_rajan
# 5  
Old 06-27-2013
You can also try this in awk :
Code:
awk '/version=/ { a=NR } { b[$0] = NR } END { for ( i in b ) if ( b[i] > a ) { print i } }  '

This will assume that string 'version=' will be only in one row of the file.
# 6  
Old 06-27-2013
Awesome! ThanksSmilie
# 7  
Old 06-27-2013
Another awk solution
Another one on similar lines

Code:
awk '{if($0 ~ /version=/) {start=1;next} if(start){print} }' filename

or

Code:
awk ' {if($0 ~ /version=/) LN=NR} {if ((LN!=0)&&(NR>LN)) {print }}' filename

Last edited by krishmaths; 06-27-2013 at 05:15 AM..
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