12 Practical Examples of Linux grep Command

Have you ever been confronted with the task of looking for a particular string or pattern in a file, yet have no idea where to start looking? Well then, here is grep to the rescue!

12 Grep Command Examples

grep is a powerful file pattern searcher that comes equipped on every distribution of Linux. If, for whatever reason, it is not installed on your system, you can easily install it via your package manager (apt-get on Debian/Ubuntu and yum on RHEL/CentOS/Fedora).

$ sudo apt-get install grep         #Debian/Ubuntu

$ sudo yum install grep             #RHEL/CentOS/Fedora

I have found that the easiest way to get your feet wet with grep is to just dive right in and use some real world examples.

1. Search and Find Files

Let’s say that you have just installed a fresh copy of the new Ubuntu on your machine, and that you are going to give Python scripting a shot. You have been scouring the web looking for tutorials, but you see that there are two different versions of Python in use, and you don’t know which one was installed on your system by the Ubuntu installer, or if it installed any modules. Simply run this command:

# dpkg -l | grep -i python

Sample Output

      ▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬

                                                    ► Read more: http://adf.ly/1nBSSZ

      ▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬