Linux Shell Scripting Cookbook - Third Edition

How to do it...

The grep command is the magic Unix utility for searching text. It accepts regular expressions and can produce reports in various formats.

1. Search stdin for lines that match a pattern:

        $ echo -e "this is a word\nnext line" | grep word 
        this is a word

2. Search a single file for lines that contain a given pattern:

        $ grep pattern filename
        this is the line containing pattern

Alternatively, this performs the same search:

        $ grep "pattern" filename
        this is the line containing pattern

3. Search multiple files for lines that match a pattern:

        $ grep "match_text" file1 file2 file3 ... 

4. To highlight the matching pattern, use the -color option. While the option position does not matter, the convention is to place options first. ...