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Using variables in AWK


 
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# 1  
Old 07-30-2009
Using variables in AWK

Hi,

I'm pretty new to AWK and was wondering if someone could let me know how to execute varibles within an AWK statement. An example is below:

NO=6
end=25

awk = 'NR == $NO, NR == $end' file1 > file2


I'm currently attempting to use this within a script but awk seems to read $NO and $end as literal words instead of the variable values they are.

I hope someone can help.

Thanks

Chris
# 2  
Old 07-30-2009
Hi.

You can either:
Code:
awk 'NR == '$NO', NR == '$end file1 > file2

or

Code:
awk -v NO=$NO -v end=$end 'NR == NO, NR == end' file1 > file2

$NO and $end are shell variables which awk doesn't understand.
# 3  
Old 07-30-2009
Thanks i'm using the second option.
 

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