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

basic_socket_acceptor::listen

Place the acceptor into the state where it will listen for new connections.

void listen(
    int backlog = socket_base::max_listen_connections);
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void listen(
    int backlog,
    boost::system::error_code & ec);
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