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basic_stream::connect (10 of 10 overloads)

Establishes a connection by trying each endpoint in a sequence.

    class Iterator,
    class ConnectCondition>
    Iterator begin,
    Iterator end,
    ConnectCondition connect_condition,
    error_code& ec);

This function attempts to connect the stream to one of a sequence of endpoints by trying each endpoint until a connection is successfully established. The underlying socket is automatically opened if needed. An automatically opened socket is not returned to the closed state upon failure. The algorithm, known as a composed operation, is implemented in terms of calls to the underlying socket's connect function.





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


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


A function object that is called prior to each connection attempt. The signature of the function object must be:

bool connect_condition(
    error_code const & ec,
    typename Protocol::endpoint const & next);

The ec parameter contains the result from the most recent connect operation. Before the first connection attempt, ec is always set to indicate success. The next parameter is the next endpoint to be tried. The function object should return true if the next endpoint should be tried, and false if it should be skipped.


Set to indicate what error occurred, if any. If the sequence is empty, set to net::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.