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connect (4 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,
    Iterator end,
    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.


An iterator pointing to the end 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.

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