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 2014. The current version is 1.89.0.

buffered_read_stream::fill (2 of 2 overloads)

buffered_read_stream::fill (2 of 2 overloads)

Fill the buffer with some data. Returns the number of bytes placed in the buffer as a result of the operation, or 0 if an error occurred.

std::size_t fill(
    boost::system::error_code & ec);