Unlocking Linux Mastery: Advanced Commands for Power Users

To View the contents of a file

Cat - This Linux command allows you to view the contents of a file

Simply typecat filenameand PressEnter

Replace "filename" with the name of the file you want to view.

Change access permissions of files

chmod -To modify the access permissions of a file, use the chmod command followed by the permission code and the file name.

The permission code consists of three digits representing read (4), write (2), and execute (1) permissions for the owner, group, and others, respectively.

Simply typechmod 644 filenameand PressEnter

For example - Here 735 is represented as,

7: Hundred's place denotes owner permission

3: Ten's place denotes group permission

5: Unit's place denotes everyones permission

Furthermore, chmod digits give the following kind of permissions:

1 = Execute
2 = Write
3 = Write & Execute
4 = Read
5 = Read & Execute
6 = Read & Write
7 = Read, Write & Execute

Now, when we put it all together, we can see what the chmod 735 command means and what it will do to your file permissions:

7: Owner can read, write and execute
3: Group can write and execute
5: Everyone can read and execute

Check your command history

history -To view the list of commands you have run in the terminal session history.

Simply typehistoryand PressEnter

This will display a numbered list of commands you executed during the current session.

Remove a directory/folder

rm - To remove a directory/ Folder.

Simply typerm filename/directorynameand PressEnter

Create an animals.txt file and view its content

touch - To create an empty file named "animal.txt,"

cat -To view the contents of the file (we discussed earlier)

Simply typetouch filenameand PressEnter

then ,typecat filenameand PressEnter

Add content in animals.txt

Vim - To open a file to add content

Simply typevim filenamePressEnter

Inserting Text: To start inserting or editing text within the file, pressifor insert mode. You can then type or modify text as needed.

Saving and Exiting: To save the changes and exit vim, pressEscto ensure you are in normal mode, and then type:wqorZZ (Shift + zz)PressEnter

To Show only the top five animals from the file

head - To display the top lines of the file

Simply typehead -5 filenamePressEnter

you can also use theheadcommand with the-noption

To Show only the bottom five animals from the file

tail -To display the last lines of the file,

Simply typetail -5 filenamePressEnter

you can also use thetailcommand with the-noption

To create another file with content in flowers.txt and to view the content.

We already discussed this earliertouch,vimandcatcommand

To find the difference between animals.txt and flowers.txt file

diff - To compare the contents of two files and find the differences

Simply typediff filename1 filename2PressEnter

Thediffcommand will display the lines that are different between the two files, if any.

Conclusion

In summary, mastering a few fundamental Linux commands empowers users to efficiently manage files and directories within the terminal. Commands like cat allow for easy viewing of file contents, while chmod facilitating the adjustment of access permissions, ensuring secure file management. Monitoring and reviewing past commands is made simple by history providing a comprehensive list of previous actions within the session.

Basic file operations, such as creation, editing, and deletion, are streamlined through commands like touch, vim, and rmenabling users to manipulate files swiftly and effectively. Furthermore, commands like 'head' and 'tail' offer quick insights by displaying the top or bottom lines of a file, respectively. For more advanced tasks, such as comparing file contents, diff provides a straightforward solution, highlighting any discrepancies between files. By familiarizing oneself with these commands, users gain greater control and efficiency in navigating the Linux environment.

I hope you found this blog helpful!

Happy learning!