Using Awk to Print Select Output

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Awk is a very powerful utility, but its syntax is less than intuitive to a beginner. Here are a few common but very powerful things you can do with awk:

# print line 2 of the file
awk 'NR == 2' myFile.txt
 
# print column 2 of the file
awk '{print $2}' myFile.txt
 
# add up column 2
awk '{s += $4} END {print s}'
 
# print all the lines with more than 80 columns
awk 'length($0) > 80' myFile.txt
 
# print the number of lines in the file
awk 'END { print NR }' myFile.txt
 
# count the number of lines where column 2 is greater than column 1
awk '$2 > $1 {print i + "1"; i++}' myFile.txt

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Last Updated on Sunday, 18 July 2010 12:38

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