Boost C++ Libraries

...one of the most highly regarded and expertly designed C++ library projects in the world. — Herb Sutter and Andrei Alexandrescu, C++ Coding Standards

This is an older version of Boost and was released in 2015. The current version is 1.89.0.

buffered_read_stream::get_io_service

Get the io_service associated with the object.

boost::asio::io_service & get_io_service();