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connect (2 of 8 overloads)

Establishes a socket connection by trying each endpoint in a sequence.

    typename Protocol,
    typename SocketService,
    typename Iterator>
Iterator connect(
    basic_socket< Protocol, SocketService > & s,
    Iterator begin,
    boost::system::error_code & ec);

This function attempts to connect a socket to one of a sequence of endpoints. It does this by repeated calls to the socket's connect member function, once for each endpoint in the sequence, until a connection is successfully established.



The socket to be connected. If the socket is already open, it will be closed.


An iterator pointing to the start of a sequence of endpoints.


Set to indicate what error occurred, if any. If the sequence is empty, set to boost::asio::error::not_found. Otherwise, contains the error from the last connection attempt.

Return Value

On success, an iterator denoting the successfully connected endpoint. Otherwise, the end iterator.


This overload assumes that a default constructed object of type Iterator represents the end of the sequence. This is a valid assumption for iterator types such as boost::asio::ip::tcp::resolver::iterator.

tcp::resolver r(io_service);
tcp::resolver::query q("host", "service");
tcp::socket s(io_service);
boost::system::error_code ec;
boost::asio::connect(s, r.resolve(q), ec);
if (ec)
  // An error occurred.