Added new overloads of experimental::make_parallel_group that may be used
to launch a dynamically-sized set of asynchronous operations, where all
operations are the same type. For example:
using op_type = decltype(
socket1.async_read_some(
boost::asio::buffer(data1),
boost::asio::deferred
)
);
std::vector<op_type> ops;
ops.push_back(
socket1.async_read_some(
boost::asio::buffer(data1),
boost::asio::deferred
)
);
ops.push_back(
socket2.async_read_some(
boost::asio::buffer(data2),
boost::asio::deferred
)
);
boost::asio::experimental::make_parallel_group(ops).async_wait(
boost::asio::experimental::wait_for_all(),
[](
std::vector<std::size_t> completion_order,
std::vector<boost::system::error_code> e,
std::vector<std::size_t> n
)
{
for (std::size_t i = 0; i < completion_order.size(); ++i)
{
std::size_t idx = completion_order[i];
std::cout << "socket " << idx << " finished: ";
std::cout << e[idx] << ", " << n[idx] << "\n";
}
}
);
Thanks go to Klemens Morgenstern for supplying part of this implementation.
This is no longer an experimental facility. The names deferred and
deferred_t have been temporarily retained as deprecated entities under
the asio::experimental namespace, for backwards compatibility.
The BOOST_ASIO_HANDLER_LOCATION((file_name, line, function_name)) macro
may be used to inform the handler tracking mechanism of a source
location. This macro declares an object that is placed on the stack.
When an asynchronous operation is launched with location information, it
outputs lines using the <action> 'n^m', prior to the 'n*m' line that
signifies the beginning of the asynchronous operation. For example:
@asio|1589423304.861944|>7|ec=system:0,bytes_transferred=5
@asio|1589423304.861952|7^8|in 'async_write' (./../../../include/asio/impl/write.hpp:330)
@asio|1589423304.861952|7^8|called from 'do_write' (handler_tracking/async_tcp_echo_server.cpp:62)
@asio|1589423304.861952|7^8|called from 'operator()' (handler_tracking/async_tcp_echo_server.cpp:51)
@asio|1589423304.861952|7*8|socket@0x7ff61c008230.async_send
@asio|1589423304.861975|.8|non_blocking_send,ec=system:0,bytes_transferred=5
@asio|1589423304.861980|<7|
If std::source_location or std::experimental::source_location are
available, the use_awaitable_t token (when default-constructed or used
as a default completion token) will also cause handler tracking to
output a source location for each newly created asynchronous operation.
A use_awaitable_t object may also be explicitly constructed with location
information.
N.B. The Windows-specific tick_count_timer example has been removed as
it has been superseded by timers based on the standard steady_clock.
It's also not clear how to map a wrapping time source to the standard
chrono concepts.
* Use asio::steady_timer rather than asio::deadline_timer.
* Use asio::dynamic_buffer rather than asio::streambuf.
* Use timed asio::io_context::run_for() function for blocking clients.
* Add example showing a custom completion token for blocking with timeouts.
for returning a C++11 std::future from an asynchronous operation's
initiating function.
To use asio::use_future, pass it to an asynchronous operation instead of
a normal completion handler. For example:
std::future<std::size_t> length =
my_socket.async_read_some(my_buffer, asio::use_future);
Where a completion handler signature has the form:
void handler(error_code ec, result_type result);
the initiating function returns a std::future templated on result_type.
In the above example, this is std::size_t. If the asynchronous operation
fails, the error_code is converted into a system_error exception and
passed back to the caller through the future.
Where a completion handler signature has the form:
void handler(error_code ec);
the initiating function returns std::future<void>. As above, an error
is passed back in the future as a system_error exception.
[SVN r84313]
io_service.notify_fork() at the appropriate times. Two new examples have been
added showing how to use this feature. Refs #3238, #4162.
* Clean up the handling of errors reported by the close() system call. In
particular, assume that most operating systems won't have close() fail with
EWOULDBLOCK, but if it does then set blocking mode and restart the call. If
any other error occurs we assume the descriptor is closed. Refs #3307.
* EV_ONESHOT seems to cause problems on some versions of Mac OS X, with the
io_service destructor getting stuck inside the close() system call. Use
EV_CLEAR instead. Refs #5021.
* Include function name in exception what() messages.
* Fix insufficient initialisers warning with MinGW.
* Make the shutdown_service() member functions private.
* Add archetypes for testing socket option functions.
* Add missing lock in signal_set_service::cancel().
* Fix copy/paste error in SignalHandler example.
* The signal header needs to be included in signal_set_service.hpp so that we
can use constants like NSIG and SIGRTMAX.
* Don't use Boost.Thread's convenience header. Use the header file that is
specifically for the boost::thread class instead.
[SVN r69467]
