# List ALL open files and network connections on the system
lsof
# List ALL network connections (TCP + UDP), numeric ports, no DNS lookups
sudo lsof -i -P -n
# See which process is listening on a specific port (e.g. 9205)
sudo lsof -i :9205 -P -n
# See all ports used by a specific process ID (PID)
sudo lsof -Pan -p <PID> -i
# See all open network connections for processes matching a name (e.g. dotnet)
sudo lsof -i -P -n | grep dotnet
# Show only listening TCP sockets (which processes are listening for connections)
sudo lsof -iTCP -sTCP:LISTEN -P -n
# List all files opened by a specific PID (logs, DLLs, configs, sockets, etc.)
sudo lsof -p <PID>
# List all open files under a specific directory (recursive)
sudo lsof +D /path/to/directory
# See which process has a specific file locked / open
sudo lsof /path/to/file
# Continuously watch for changes in open files/connections (Ctrl+C to stop)
sudo watch -n 2 "lsof -i -P -n | grep <something>"
