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

Wait for the socket to become ready to read, ready to write, or to have pending error conditions.

void wait(
    wait_type w);
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void wait(
    wait_type w,
    boost::system::error_code & ec);
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