Book Image

Learn Linux Quickly

By : Ahmed AlKabary
5 (1)
Book Image

Learn Linux Quickly

5 (1)
By: Ahmed AlKabary

Overview of this book

Linux is one of the most sought-after skills in the IT industry, with jobs involving Linux being increasingly in demand. Linux is by far the most popular operating system deployed in both public and private clouds; it is the processing power behind the majority of IoT and embedded devices. Do you use a mobile device that runs on Android? Even Android is a Linux distribution. This Linux book is a practical guide that lets you explore the power of the Linux command-line interface. Starting with the history of Linux, you'll quickly progress to the Linux filesystem hierarchy and learn a variety of basic Linux commands. You'll then understand how to make use of the extensive Linux documentation and help tools. The book shows you how to manage users and groups and takes you through the process of installing and managing software on Linux systems. As you advance, you'll discover how you can interact with Linux processes and troubleshoot network problems before learning the art of writing bash scripts and automating administrative tasks with Cron jobs. In addition to this, you'll get to create your own Linux commands and analyze various disk management techniques. By the end of this book, you'll have gained the Linux skills required to become an efficient Linux system administrator and be able to manage and work productively on Linux systems.
Table of Contents (24 chapters)

Changing file permissions

Now, what if we want to give elliot permission to edit the file mysmurf without changing file ownership as we did before? Well! This is very simple; you can use the chmod command to change file permissions.

Let's first switch to the root user:

elliot@ubuntu-linux:/home/smurf$ su - 
Password:
root@ubuntu-linux:~# cd /home/smurf
root@ubuntu-linux:/home/smurf#

Now you can add the write permission for others (everyone else) by running the command:

root@ubuntu-linux:/home/smurf# chmod o+w mysmurf

Here o+w means others+write, which means adding the write permission to others. Now do a long listing on mysmurf:

root@ubuntu-linux:/home/smurf# ls -l mysmurf
-rw-r--rw- 1 smurf developers 29 Oct 23 11:34 mysmurf

As you can see, others can now read and write rw- to the mysmurf file. Now, switch back to user elliot and try to add the line I am not smurf! again:

root@ubuntu-linux:/home/smurf# su elliot
elliot@ubuntu-linux:/home/smurf$ echo "I am not smurf!" &gt...