Linux Basics

More than 90% of cloud servers and many of the webservers are running on the Linux platform so it is handy if we are aware of the Linux basic commands

1.) PWD : Present working Directory

2) CD: Change directory where CD ~ moves to home directory and cd .. just parent directory 

3.) ls: List files folders and executable files in the current directory

4.) apt: Advanced Packaging tool (mainly used to install / update new software packaging)

Time to try the combination of CD and ls

What is the output of  ls cd .. ? or ls  ..?

Now try ls /var/log

cd -- will points previously worked directory 

what about cd ../.. ? 😉

(yes will move to double strap back )

linux commands con be tuned based on our requirements with flags (- with alphabets eg: -a or -- with full name eg:--all)

To get the list of flage type man (manual)  command with wich linux command like man ls or man pwd

Lets discuss about the file permissions and access

we cam see lot of -rw-r--r and x d will decode one by one 😎

- : indicates file

d: indicates directory

l: indicates link

rwx: read, write and executable permission for the owner

r--: read write and executable permission for the group users who owns the file

Now lets create a script and will give a access to it

To execute the test.sh do ./test.sh where '.' represent current directory

unfortunately we don't have permission to execute 😱

will give executable permission like below chmod +x test.sh

to execute the file used the command ./test.sh else can do cat test.sh

Cool 💪.

Useful like for the reference : https://tldp.org/HOWTO/VMS-to-Linux-HOWTO/examples.html

Cheat lnk 1: https://learncodethehardway.org/unix/bash_cheat_sheet.pdf