write (2 of 6 overloads)

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#### write (2 of 6 overloads)

Write a certain amount of data to a stream before returning.

    template<
        typename SyncWriteStream,
        typename ConstBufferSequence,
        typename CompletionCondition>
    std::size_t write(
        SyncWriteStream & s,
        const ConstBufferSequence & buffers,
        CompletionCondition completion_condition);

This function is used to write a certain number of bytes of data to a stream. The call will block until one of the following conditions is true:

- All of the data in the supplied buffers has been written. That is, the bytes transferred is equal to the sum of the buffer sizes.
- The completion_condition function object returns true.

This operation is implemented in terms of one or more calls to the stream's write_some function.

###### Parameters

s

  The stream to which the data is to be written. The type must support the SyncWriteStream concept.

buffers

  One or more buffers containing the data to be written. The sum of the buffer sizes indicates the maximum number of bytes to write to the stream.

completion_condition

  The function object to be called to determine whether the write operation is complete. The signature of the function object must be:

      bool completion_condition(
        const boost::system::error_code& error, // Result of latest write_some
                                                // operation.

        std::size_t bytes_transferred           // Number of bytes transferred
                                                // so far.
      );

  A return value of true indicates that the write operation is complete. False indicates that further calls to the stream's write_some function are required.

###### Return Value

The number of bytes transferred.

###### Exceptions

boost::system::system_error

  Thrown on failure.

###### Example

To write a single data buffer use the buffer function as follows:

    boost::asio::write(s, boost::asio::buffer(data, size),
        boost::asio::transfer_at_least(32));

See the buffer documentation for information on writing multiple buffers in one go, and how to use it with arrays, boost::array or std::vector.