Linux awk Command Examples

Linux awk Command Examples

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awk '{print $2, $3}' my.txt

    print 2nd & 3rd fields separated by space

awk '{print $2 "," $3}' my.txt

    print 2nd & 3rd field separated by comma

awk '/error/' my.txt

    print lines containing the text "error"

awk '{sum=$1+$2; print sum}' my.txt

    sum up 1st and 2nd fields of each line

awk '{print NR, $0}' my.txt

    add line number to each line and print it

awk '{print NF}' my.txt

    print the number of fields in each line

awk '{print $1, $NF}' my.txt

    print 1st and last fields

awk 'NR>1 {print}' my.txt

    skip the header line

awk '$2 >100' my.txt

    print lines where 2nd field is > 100

awk 'NF>0' my.txt

    remove empty or whitespace-only lines

awk '$1 == 100' my.txt

    print lines where 1st field equals to 100

awk '{s+=$2; c++} END {print s/c}' my.txt

    compute average of 2nd field

awk '$1>100 {s+=$2; c++} END {print s/c}' my.txt

    average with condition

awk '{print toupper($2)}' my.txt

    print 2nd field in uppercase

awk '$1=="ERR" {print $2}' my.txt

    print 2nd field if 1st field is "ERR"

awk '{print "Name:", $1, "Age:", $2}' my.txt

    formatted printing

awk -F',' '{print $2, $3}' my.csv

    use comma "," as the field separator

awk '{print substr($2,1,3)}' my.txt

    extract substring from 2nd field

awk 'function sq(x) {return x*x} {print sq($2)}' my.txt

    define a function

awk '!seen[$1]++' my.txt

    remove duplicate lines based on 1st column

awk 'length($2) > 3' my.txt

    print lines where length of 2nd field is > 3

awk '{gsub(/old/,"new"); print}' my.txt

    replace every "old" with "new"

awk '$1 ~ /ERR/' my.log

    print lines where 1st field matches pattern

awk '$1 !~ /ERR/' my.log

    print lines where 1st field doesn't match pattern

awk '$1 ~ /^[0-9]+$/' my.log

    print lines where 1st field has only digits

awk '{$1=$1; print}' my.txt

    trim whitespace and collapse internal spaces

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