Explanation Needed


 
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Old 12-08-2010
Explanation Needed

Hi all,

I'm very new to UNIX. I have got a coding, where i dont understand the below part. Could someone please explain it in detail?
Code:
awk 'NR > 1; NR == 1 { S = $0 } END { print S }' $textfile.bak > $textfile

could someone explain what
Code:
awk 'NR > 1; NR == 1 { S = $0 } END { print S }'

does in detail? it would be very helpful..

thanks in advance
Rahul

Last edited by Franklin52; 12-08-2010 at 03:45 AM.. Reason: Please use code tags, thank you
# 2  
Old 12-08-2010
Quote:
Originally Posted by raghulshekar
Hi all,

I'm very new to UNIX. I have got a coding, where i dont understand the below part. Could someone please explain it in detail?
Code:
awk 'NR > 1; NR == 1 { S = $0 } END { print S }' $textfile.bak > $textfile

could someone explain what
Code:
awk 'NR > 1; NR == 1 { S = $0 } END { print S }'

does in detail? it would be very helpful..

thanks in advance
Rahul
Explanation:
Code:
NR > 1 condition without an action: print the line if line number > 1
NR == 1 { S = $0 } assign the first line to variable S
END { print S } print the first line

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