First run and permissions

portop needs no configuration. What it can see depends on the user it runs as.

Start

portop            # every listening and established socket
portop 8080       # filtered on a port
portop --listen   # listening sockets only

The table refreshes every two seconds. Press ? for help and q to quit.

Permissions

System	Without privileges	With privileges
Linux	Other users' sockets appear without a process; the status bar counts them, for example `(3 hidden — try sudo)`.	`sudo portop` resolves every row and lets portop read the firewall.
macOS	`lsof` omits other users' sockets entirely.	`sudo portop` lists them.
Windows	Every socket comes with its PID; details of elevated or other users' processes are not readable.	An Administrator terminal reads them.

Settings and baseline files written under sudo stay owned by your user, so later runs without sudo can still update them.

Terminal

Use a terminal with 256 colors or true color. In a minimal SSH or container session where TERM=xterm, set TERM=xterm-256color or COLORTERM=truecolor.