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


The open method is used to open a TCP connection to a given server on a given port.


var instanceOfTCPSocket =, port[, options]);


A string representing the host name of the server to connect to.
A number representing the port to connect to.

An object specifying the details of the socket. This object expects one or more of the following properties:

  • useSecureTransport: use the value to create an SSL socket. Defaults to false.
  • binaryType: a string with the value string (default) or arraybuffer. If the latter is used the argument for the send() method must be an ArrayBuffer and the data received from the server will be available as an ArrayBuffer. Otherwise, a string is expected.

Note: In an older verson of the API (supported in Firefox 1.0.1), useSecureTransport was called useSSL. You can pass both the older and newer options in if wished, to avoid breaking old versions of Firefox OS. See here for an example.


It returns a new TCPSocket object connected to the provided host on the provided port.


var socket ="", 80);


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, mkato, Andrew Sutherland, kscarfone, .vimrc, Jeremie
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