---
title: roDatagramSocket
slug: develop/rodatagramsocket
docTags: 
createdAt: 2025-03-11T07:07:18.732Z
---

:::hint{type="danger"}
Use this object to receive multicast packets and join a multicast group by calling the `JoinMulticastGroup()` method.
:::

This object both sends and receives UDP packets. Use *roDatagramSocket* if you need the player to communicate using protocols such as SSDP, which only allow a server to respond to the source of a received request. The JavaScript equivalent is Node.js Dgram API.

Received packets are delivered to the message port as *roDatagramEvent* objects.

## ifDatagramSocket

### GetFailureReason() As String

Returns additional information if the `BindToLocalPort` or `Sendto` methods fail.

### BindToLocalPort(port As Dynamic) As Boolean

Prepares to accept incoming UDP packets on the specified port. Passing an integer to this method will specify a standard port number. This method can also accept an associative array to provide more control over the binding. The associative array must contain the `port` but can also contain the `interface` name. This method returns `True` upon success and `False` upon failure.

- `port` <font color="#704ae0">integer</font>: The local port number to bind to.
- `interface` <font color="#704ae0">integer</font> or <font color="#704ae0">string</font>: Either the name of a network interface as a string (such as "eth0" or "wlan0") or the integer associated with the network interface index:
  - -1: Any (this is the default value)
  - 0: Ethernet
  - 1: WiFi
  - 2: Modem
  - 32767: Loopback (i.e. packets will only be received from within the player itself)

### GetLocalPort() As Integer

Returns the local port to which the socket is bound. Use this method if you passed a port number of 0 to `BindToLocalPort` and need to determine which port the player has selected.

### SendTo(destination\_address As String, destination\_port As Integer, packet As Object) As Integer

Sends a single UDP packet, which can be an *roString* or *roByteArray*, to the specified address and port. This method returns 0 upon success and a negative error code upon failure.

### JoinMulticastGroup(address as String) as Boolean

Joins the multicast group for the specified address on all interfaces that are currently up. This method returns `True` upon success and `False` upon failure. In the event of failure, `GetFailureReason()` may provide additional information. To ensure that you are joined on all network interfaces, you should register for *roNetworkHotplug* events and call the `JoinMulticastGroup()` method in response to the arrival of new networks.

## ifUserData

### SetUserData(user\_data As Object)

Sets the user data that will be returned when events are raised.

### GetUserData() As Object

Returns the user data that has previously been set via `SetUserData()`. It will return Invalid if no data has been set.

## ifMessagePort

### SetPort(port As roMessagePort)

Posts messages of type *roDatagramEvent* to the attached message port.

## ifIdentity

### GetIdentity() As Integer

:::hint{type="info"}
The *ifIdentity* interface has been deprecated. We recommend using the *ifUserData* interface instead.
:::