Software > Linux tools >

(on Wikipedia)
https://www.gnu.org/software/grep/

• There is also egrep and pgrep.

• ack replaces it.

Usage ∞

Some basic examples:

cat file.txt|grep "some text"
ls -al|grep -i filename

• Use -v for an inverted match (all lines WITHOUT)

• To find a keyword within files:

  • grep -r KEYWORD *
  • But it doesn’t tell you what files the match is in.