CC-Tweaked/doc/events/rednet_message.md

---
module: [kind=event] rednet_message
see: modem_message For raw modem messages sent outside of Rednet.
see: rednet.receive To wait for a Rednet message with an optional timeout and protocol filter.
---

<!--
SPDX-FileCopyrightText: 2021 The CC: Tweaked Developers

SPDX-License-Identifier: MPL-2.0
-->

The [`rednet_message`] event is fired when a message is sent over Rednet.

This event is usually handled by [`rednet.receive`], but it can also be pulled manually.

[`rednet_message`] events are sent by [`rednet.run`] in the top-level coroutine in response to [`modem_message`] events. A [`rednet_message`] event is always preceded by a [`modem_message`] event. They are generated inside CraftOS rather than being sent by the ComputerCraft machine.

## Return Values
1. [`string`]: The event name.
2. [`number`]: The ID of the sending computer.
3. [`any`]: The message sent.
4. <span class="type">[`string`]|[`nil`]</span>: The protocol of the message, if provided.

## Example
Prints a message when one is sent:
```lua
while true do
  local event, sender, message, protocol = os.pullEvent("rednet_message")
  if protocol ~= nil then
    print("Received message from " .. sender .. " with protocol " .. protocol .. " and message " .. tostring(message))
  else
    print("Received message from " .. sender .. " with message " .. tostring(message))
  end
end
```