awk

awk 'script' filename | where 'script' is a set of commands that are understood by awk

Bash

awk <'script'> filename

Basic

Bash

awk '//{print}' /etc/hosts

• filter | pattern

Bash

awk '/localhost/{print}' /etc/hosts

• filter c*m | example all words with com cam cem etc

Bash

awk '/c.m/{print}' /etc/hosts

• use *

Bash

awk '/l*c/{print}' /etc/hosts

• Take for example the set [al1], here awk will match all strings containing character a or l or 1 in a line in the file /etc/hosts.

Bash

awk '/[al1]/{print}' /etc/hosts

• matches strings starting with either K or k followed by T

Bash

awk '/[Kk]T/{print}' /etc/hosts 

• It matches all the lines that start with the pattern

Bash

awk '/^ff/{print}' /etc/hosts

• It matches all the lines that end with the pattern

Bash

awk '/ost$/{print}' /etc/hosts

Standard use cases

• filter out row | print second row (NAME) | docker service

Bash

docker service ls | awk '{print $2}'