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README.md

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+Service Butler - Quick Start Guide
+==================================
+
+This script is a "butler" for your services (especially game servers). It saves RAM and CPU by running them only when someone actually wants to connect.
+
+Install
+-------
+
+    make install
+
+It will place the binary and configs on it's place.
+
+The next step is enable and start service:
+
+    systemctl enable port-butler
+    systemctl start port-butler
+
+How it works
+------------
+
+The butler follows a simple loop for each service you configure:
+
+1.  **Sleeping & Listening**: It sits on your service's port, waiting. The real service is offline.
+2.  **Wake Up Call**: As soon as someone tries to connect, the butler catches the attempt, tells them to hold on (by closing the connection), and immediately starts waking up the real service.
+3.  **Waking Up**: It runs your `start_command`. After a short `startup_delay_sec`, it begins watching.
+4.  **Watching**: It periodically runs your `check_command` to see if anyone is using the service. As long as people are active, it does nothing.
+5.  **Going to Sleep**: Once the service has been empty for `idle_limit_sec`, the butler runs the `stop_command` and goes back to step 1.
+
+If the script is restarted, it uses `is_running_command` to see if the service is already up, so it can jump straight to the "Watching" step without restarting it.
+
+Configuration
+-------------
+
+See `config.ini` for example.
+
+It placed to `/etc/butler.ini` during installation.
+
+Each service gets its own section, like `[minecraft]`. Here are the options:
+
+*   `start_command`
+    The shell command to start your service. e.g., `systemctl start minecraft`.
+
+*   `stop_command`
+    The shell command to stop your service. e.g., `systemctl stop minecraft`.
+
+*   `is_running_command`
+    A command that checks if the service is already active. This is crucial for when the butler script restarts. It should exit with `0` if running, and non-zero otherwise. The `systemctl is-active --quiet <service>` command is perfect for this.
+
+*   `check_command`
+    The most important command. It checks if the service is being used. The butler only cares about the exit code: `0` means "active", anything else means "idle".
+
+*   `listen_port`
+    The public port of your service (e.g., `25565` for Minecraft). The butler will listen here when the service is down.
+
+*   `listen_host`
+    The IP to listen on. `0.0.0.0` is what you want 99% of the time, as it means "listen for connections from anywhere."
+
+*   `check_interval_sec`
+    How often (in seconds) to run the `check_command` while the service is up.
+
+*   `idle_limit_sec`
+    How long (in seconds) the service can be idle before the butler shuts it down.
+
+*   `startup_delay_sec`
+    A short pause (in seconds) after starting the service before the first activity check. This gives your server time to fully load.