a SwiftBar-based macOS menu-bar app that displays open ports and lets you kill them

watch-and-kill-ports.sh

#!/usr/bin/env bash

# SwiftBar plugin: Open Listening Ports Monitor
# Displays open TCP listening ports and lets you kill your own processes

current_user=$(whoami)

# Get listening ports with numeric values only
open_ports=$(lsof -iTCP -sTCP:LISTEN -n -P 2>/dev/null | awk -v cu="$current_user" 'NR > 1 {
    user = $3
    cmd = $1
    pid = $2
    port_field = $9
    sub(/.*:/, "", port_field)          # Extract everything after the last ":"
    sub(/ \(.*\)$/, "", port_field)     # Remove trailing " (LISTEN)"
    if (port_field ~ /^[0-9]+$/) {
        print user "\t" cmd "\t" pid "\t" port_field
    }
}' | sort -k4n)

num_ports=$(echo "$open_ports" | grep -c . || echo 0)

# Menu bar item
echo "🔌 $num_ports"

echo "---"
echo "Refresh | refresh=true"

if [ "$num_ports" -eq 0 ]; then
    echo "No open listening ports"
    exit 0
fi

echo "---"

# List each port
echo "$open_ports" | while IFS=$'\t' read -r user cmd pid port; do
    if [ "$user" = "$current_user" ]; then
        echo "$port — $cmd (PID: $pid)"
        echo "--Kill gently (SIGTERM) | bash=/bin/kill param1=$pid terminal=false refresh=true"
        echo "--Force kill (SIGKILL) | bash=/bin/kill param1=-9 param2=$pid terminal=false refresh=true color=red"
    else
        echo "$port — $cmd (PID: $pid, user: $user) | color=gray"
    fi
done