how to check if a port is being used mac code example
Example 1: list used ports on mac
sudo lsof -PiTCP -sTCP:LISTEN
COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
GitHub 850 grgarside 6u IPv4 0x23c345381d089301 0t0 TCP localhost:25035 (LISTEN)
Example 2: check all the ports in use mac
$ npx kill-port 3000 8080 8081
Process on port 3000 killed
Process on port 8080 killed
Process on port 8081 killed