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UNIX sockets and other stream types

The connection class is templatized on the stream type. Any object fulfilling the Stream concept may be used as template argument.

Convenience type aliases

This library provides helper type aliases for the most common cases:


Stream type

Type alias

SSL over TCP



Plaintext TCP



UNIX sockets



Only available if BOOST_ASIO_HAS_LOCAL_SOCKETS is defined.

This example employs a UNIX domain socket to establish a connection to a MySQL server.

Streams that are not sockets

When the Stream template argument for your connection fulfills the SocketStream type requirements, you can use the member functions connection::connect and connection::close to establish and finish connections with the MySQL server. If you are using any of the convenience type aliases (TCP or UNIX, either over TLS or not), then this is your case.

If your stream type is not based on a socket, you can't use those convenience member functions. This would be the case if you are using Windows named pipes (i.e. boost::asio::windows::stream_handle). Instead, to establish a connection, you should follow these two steps, roughly equivalent to what connection::connect does for sockets:

To clean up a connection, follow these two steps, roughly equivalent to connection::close: