Linux Basics

 Useful ls commands

ls -l -> lists all the details regarding files in the current directory

ls -a -> show hidden files as well. A file starting with . is considered hidden in linux.

ls -r -> reversing the order

ls -h -> size in human readable format

ls -t -> sort by time

ls -S -> sort by size

ls -X -> sort by extension 

ls -R -> recursively show content of subdirectory 

ls -1 -> listing file with one option. One per line. 

ls | cowsay -> list in funny way

ls —color=never (double dash) to remove the colouring


Remember, every expert was once a beginner. With patience and practice, you'll soon be navigating the Linux file system like a pro!


pwd command: It has two addition options

pwd -L : logical means as per current structure
pwd -P: physical which means as per the actual structure

User:
User creation:
sudo useradd <user-name>
sudo useradd sitendra

Details about a user
cat /etc/passwd

sudo grep -w '<username>' /etc/passwd


unset keyword: It is used to remove the variable. 
Example:
unset var1 

For loop:

for item in $(seq 1 100);
do
    echo "item #:  $item"
done


Check the linux version details
cat /etc/os-release

Check the Linux platform architecture
uname -m

awk command is used to find lines in a file and perform actions on those lines. 


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