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###### basic_stream::connect (7 of 10 overloads)

Establishes a connection by trying each endpoint in a sequence.

Synopsis

    template<
        class EndpointSequence,
        class ConnectCondition>
    Protocol::endpoint
    connect(
        EndpointSequence const& endpoints,
        ConnectCondition connect_condition);

Description

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.

Parameters

Name | Description
--- | ---
`endpoints` | A sequence of endpoints.
`connect_condition` | 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.

Return Value

The successfully connected endpoint.

Exceptions

Type | Thrown On
--- | ---
`boost::system::system_error` | Thrown on failure. If the sequence is empty, the associated error code is `net::error::not_found`. Otherwise, contains the error from the last connection attempt.