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basic_system_executor::query (3 of 3 overloads)

Query the occupancy (recommended number of work items) for the system context.

std::size_t query(
    execution::occupancy_t ) const;

Do not call this function directly. It is intended for use with the query customisation point.

For example:

boost::asio::system_executor ex;
std::size_t occupancy = boost::asio::query(
    ex, boost::asio::execution::occupancy);