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read (6 of 8 overloads)

Attempt to read a certain amount of data from a stream before returning.

    typename SyncReadStream,
    typename Allocator>
std::size_t read(
    SyncReadStream & s,
    basic_streambuf< Allocator > & b,
    boost::system::error_code & ec);

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

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



The stream from which the data is to be read. The type must support the SyncReadStream concept.


The basic_streambuf object into which the data will be read.


Set to indicate what error occurred, if any.

Return Value

The number of bytes transferred.


This overload is equivalent to calling:

    s, b,
    boost::asio::transfer_all(), ec);