awk¶

Pattern scanning and processing language (https://www.gnu.org/software/gawk/)

To check awk version

awk --version

To print the first column/field of a file

awk '{print $1}' <file>

To sum integers from a file or stdin (one integer per line)

printf '1\n2\n3\n' | awk '{ sum += $1} END {print sum}'

To use a specific character as field separator

printf '1:2:3' | awk -F ":" '{print $1+$2+$3}'

To specify an output field separator (OFS) character

printf '1 2 3' | awk 'BEGIN {OFS=":"}; {print $1,$2,$3}'

To print lines matching a specific condition

printf "george jetson\nolive oyl\nbeetle bailey" | awk '$2=="bailey"{print $0}'

To print lines matching a regular expression

printf "george jetson\nolive oyl\nbeetle bailey" | awk '/ley$/{print $0}'