Find and Kill Process Using a Specific Port

#!/bin/bash

PORT="$1"

# Check if a port number was provided
if [ -z "$PORT" ]; then
    echo "Usage: $0 <port_number>"
    echo "Example: $0 3000"
    exit 1
fi

# Find PIDs using the specified port
PIDS=$(lsof -t -i :"$PORT" 2>/dev/null)

# Check if any processes were found
if [ -z "$PIDS" ]; then
    echo "No process found using port $PORT."
else
    echo "Process(es) using port $PORT: $PIDS"
    read -p "Do you want to kill these processes? (y/N): " choice
    
    # Convert choice to lowercase for case-insensitive comparison
    choice=${choice,,}

    if [[ "$choice" == "y" ]]; then
        # Use 'kill -9' for forceful termination
        kill -9 "$PIDS"
        if [ $? -eq 0 ]; then
            echo "Process(es) $PIDS killed."
        else
            echo "Failed to kill process(es) $PIDS." >&2
            exit 1
        fi
    else
        echo "Processes not killed."
    fi
fi