|  | 
            Query the current value of the blocking property.
          
static constexpr execution::blocking_t query(
    execution::blocking_t );
            Do not call this function directly. It is intended for use with the
            query customisation
            point.
          
For example:
asio::system_executor ex;
if (asio::query(ex, asio::execution::blocking)
      == asio::execution::blocking.always)
  ...