how to check which application is running on port in linux code example

Example 1: linux query port use by pid

$ sudo netstat -nlp | grep :80
tcp  0  0  0.0.0.0:80  0.0.0.0:*  LISTEN  125004/nginx

Example 2: linux how to see ports in use

sudo netstat -tulpn | grep LISTEN

sudo lsof -i:22 # see a specific port such as 22