grep.md

Grep

Search for hashtags:

cat file | grep -o '#[[:alnum:]]*'

Search for IPv4 addresses:

$ grep -E -o "([0-9]{1,3}[\.]){3}[0-9]{1,3}" file.txt

Search for an email address:

grep -E -o "\b[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Za-z]{2,6}\b" file.txt