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connect (6 of 12 overloads)

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

    typename Protocol,
    typename Executor,
    typename Iterator>
Iterator connect(
    basic_socket< Protocol, Executor > & 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(my_context);
tcp::resolver::query q("host", "service");
tcp::resolver::results_type e = r.resolve(q);
tcp::socket s(my_context);
boost::system::error_code ec;
boost::asio::connect(s, e.begin(), e.end(), ec);
if (ec)
  // An error occurred.