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Using AWK to get a specific line using a variable

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# 1  
Old 10-03-2012
MySQL [solved] Using AWK to get a specific line using a variable
Hi

I have a text like this
example.input
Code:
1 red
2 blue
3 green

If I set this
Code:
c=2

Then try
Code:
awk 'NR==$c { print $2 }' example.input

I do get nothing

If I try
Code:
awk 'NR==2 { print $2 }' example.input

i get
Code:
blue

I know this can e down with head/tail/sed, but I like it to work in AWK

What is wrong?
Last edited by Jotne; 10-03-2012 at 04:13 AM..
# 2  
Old 10-03-2012
Code:
awk -v c=2 'NR==c { print $2 }' example.input

Shell and awk variables are different.
# 3  
Old 10-03-2012
Code:
c=2
awk -v VM="$c" 'NR == VM{print $2}' file

# 4  
Old 10-03-2012
found solution my self using google some more Smilie

Code:
awk 'NR=='$c' { print $2 }' example.input

adding singe quote

Thanks for your quick responce
# 5  
Old 10-03-2012
That solution is worse than the ones other people posted. There's two proper ways to get a variable into awk, and that's not either of them Smilie
# 6  
Old 10-03-2012
Code:
export c=2
awk 'NR == ENVIRON["c"] { print $2 }' example.input

This User Gave Thanks to rdrtx1 For This Post:
Corona688
# 7  
Old 10-03-2012
Quote:
Originally Posted by Corona688
That solution is worse than the ones other people posted. There's two proper ways to get a variable into awk, and that's not either of them Smilie
Why is it worse?
Is it more slow?
May not work with all variable?

For me it works, and its minimum of programing
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