This API is available on Firefox OS for privileged or certified applications only.


The ondata property is used to specify an event handler to receive data events. Those events are triggered each time data is available from the server.

Note: At any time, it's possible to pause reading and receiving data by calling the socket's suspend() method. The data event will not be triggered until resume() is called.


instanceOfTCPSocket.ondata = funcRef

Where funcRef is a function to be called when the data event occurs.

This callback function will get a TCPSocketEvent object as its first parameter.


Such events are simple JavaScript objects with the following properties:

The TCPSocket object which fired the event.
A string defining the type of the event. Its value can be one of the following: open, error, data, drain, or close.
The data related to the event, if any.

In case of data, the data property contains the data from the server. Depending on the value of the binaryType option passed to the open() method, the data property will be a string or an ArrayBuffer.


Not part of any specification yet; however, this API is discussed at W3C as part of the System Applications Working Group under the Raw Sockets proposal.

See also

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 Contributors to this page: chrisdavidmills, teoli, jsx, kscarfone, Jeremie
 Last updated by: chrisdavidmills,