CLI Drills

Drill2.sh

curl -o "harrypotter-gobletoffire.txt"  https://raw.githubusercontent.com/bobdeng/owlreader/master/ERead/assets/books/Harry%20Potter%20and%20the%20Goblet%20of%20Fire.txt
#to take the url of file given and storing as text file using curl -o

head -n 3 harrypotter-gobletoffire.txt 
#to get first lines of code we use head command

head -n 5  
#harrypotter-gobletoffire.txt

tail -n 10  harrypotter-gobletoffire.txt
#this means last 10lines of code we use tail for it

cat harrypotter-gobletoffire.txt|grep -c  Harry

cat harrypotter-gobletoffire.txt|grep Harry
#this one displays the text highlighting the given name here given harry
 
cat harrypotter-gobletoffire.txt|grep -c  Ron

cat harrypotter-gobletoffire.txt|grep -c Hermione

cat harrypotter-gobletoffire.txt|grep -c Dumbledore


sed -n '100,200p' harrypotter-gobletoffire.txt -- to get 100 to 200 lines

tr -sc '[:alpha:]' '[\n*]' <harrypotter-gobletoffire.txt | tr '[:upper:]' '[:lower:]'|sort|uniq|wc -l
10219
#to count unique characters first we are taking words in it and converting uppercase to lower case and removing duplicates and giving count 


Processes and Ports
ps 
# to get pids

ps -j
# to get ppids

ps -eo %cpu--sort=-%cpu | head -n 4 
#first 3 cpus in sorting order

ps -eo %mem--sort=-%mem | head -n 4  
#first 3 mem in sorting order
   
python3 -m http.server 8000 
s#tarted server on 8000


python3 -m http.server 90 
#Started server 90

netstat -tuln
#to know tcp and udp ports                             

netstat -tuln | grep 5432
#to know on 5432

#Managing software

sudo apt install htop

sudo apt install nginx

sudo apt install vim

sudo apt remove nginx --- it is to remove nginx
 
 
 #Misc
 
 curl ifconfig.me
 #local ip address
 
 nslookup google.com
 #ip address of google.com
 
 ping www.google.com 
 #to check if Internet is working using CLI
 
 #Node can also be used in a terminal window as a Read-Evaluate-Print-Loop, or REPL. This functionality allows you execute JavaScript commands from the command line.