Added missing compatibility with <codeclass="computeroutput"><spanclass="identifier">associated_immediate_executor</span></code>
to <codeclass="computeroutput"><spanclass="identifier">any_completion_handler</span></code>.
</li>
<liclass="listitem">
Fixed a null pointer dereference that occurs when using <codeclass="computeroutput"><spanclass="identifier">query</span></code>,
<codeclass="computeroutput"><spanclass="identifier">require</span></code> or <codeclass="computeroutput"><spanclass="identifier">prefer</span></code> with an empty <codeclass="computeroutput"><spanclass="identifier">any_executor</span></code>.
</li>
<liclass="listitem">
Added a workaround in <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">coro</span></code>
for a spurious syntax error when compiling with MSVC.
</li>
<liclass="listitem">
Fixed an integer truncation issue in per-operation cancellation, when using
the reactor backend on 64-bit Windows.
</li>
<liclass="listitem">
Added a compile-time check for a minimum Linux kernel version of 5.10,
when <codeclass="literal">io_uring</code> support is enabled.
</li>
<liclass="listitem">
Fixed a compile error in the converting move constructors for <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">basic_channel</span></code> and <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">basic_concurrent_channel</span></code>.
</li>
<liclass="listitem">
Fixed a memory leak on some <codeclass="computeroutput"><spanclass="identifier">signal_set</span></code>
to not use a deprecated implicit copy constructor.
</li>
<liclass="listitem">
Fixed a copy/paste error in the <codeclass="computeroutput"><spanclass="identifier">dev_poll_reactor</span></code>
backend.
</li>
<liclass="listitem">
Fixed the <codeclass="literal">io_uring</code> backend to ensure the internal timeout
operations, used to implement <codeclass="computeroutput"><spanclass="identifier">io_context</span><spanclass="special">::</span><spanclass="identifier">run_for</span></code>
and <codeclass="computeroutput"><spanclass="identifier">io_context</span><spanclass="special">::</span><spanclass="identifier">run_until</span></code>, are cleaned up correctly.
</li>
<liclass="listitem">
Eliminated some duplicated state in the <codeclass="computeroutput"><spanclass="identifier">co_spawn</span></code>
implementation's entry point, reducing memory consumption.
Added missing handler tracking source location support to <codeclass="computeroutput"><spanclass="identifier">awaitable</span><spanclass="special"><></span></code>-based
coroutine's ability to <codeclass="computeroutput"><spanclass="identifier">co_await</span></code>
asynchronous operations packaged as function objects.
</li>
<liclass="listitem">
Add missing handler tracking source location support to <codeclass="computeroutput"><spanclass="identifier">co_composed</span></code>.
</li>
<liclass="listitem">
Fixed suppression of spurious 'potential null dereference' warnings, to
work with older compilers.
</li>
<liclass="listitem">
Fixed a bug where passing the deprecated <codeclass="computeroutput"><spanclass="identifier">const_buffers_1</span></code>
and <codeclass="computeroutput"><spanclass="identifier">mutable_buffers_1</span></code> types
to <codeclass="computeroutput"><spanclass="identifier">asio</span><spanclass="special">::</span><spanclass="identifier">buffer</span><spanclass="special">()</span></code>
would result in the contiguous iterator overloads being incorrectly chosen.
</li>
<liclass="listitem">
Disabled the runtime Windows version test unless targeting older Windows
versions.
</li>
<liclass="listitem">
Fixed compatibility between buffered stream wrappers and move-constructible
streams, such as <codeclass="computeroutput"><spanclass="identifier">ssl</span><spanclass="special">::</span><spanclass="identifier">stream</span><spanclass="special"><></span></code>.
</li>
<liclass="listitem">
Marked <codeclass="computeroutput"><spanclass="identifier">ip</span><spanclass="special">::</span><spanclass="identifier">address_v4</span><spanclass="special">::</span><spanclass="identifier">to_ulong</span></code> as deprecated in the documentation.
Fixed a potential, Windows-specific program termination due to exceptions
that should have been allowed to escape from a destructor.
</li>
<liclass="listitem">
Fixed <codeclass="computeroutput"><spanclass="identifier">this_coro</span></code> to prevent
inadvertent <codeclass="computeroutput"><spanclass="identifier">co_await</span></code> of
boolean expressions.
</li>
<liclass="listitem">
Fixed result handling in <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">use_coro</span></code>
implementation.
</li>
<liclass="listitem">
Fixed variadic template emulation for <codeclass="computeroutput"><spanclass="identifier">is_async_operation</span></code>
and <codeclass="computeroutput"><spanclass="identifier">completion_signature_of</span></code>.
</li>
<liclass="listitem">
Fixed incorrect reuse of a moved-from result in <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">promise</span></code>.
</li>
<liclass="listitem">
Fixed <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">coro</span></code> use with custom allocators.
</li>
<liclass="listitem">
Fixed clean up of internal I/O object structures when using <codeclass="literal">io_uring</code>.
</li>
<liclass="listitem">
Use cached offset when seeking a file with seek_cur on Windows.
</li>
<liclass="listitem">
Added immediate completion to asynchronous operation requirements.
Added the ability to customise the execution of a completion handler when
an operation completes immediately. This change adds the <codeclass="computeroutput"><spanclass="identifier">associated_immediate_executor</span></code> associator
function, and <codeclass="computeroutput"><spanclass="identifier">immediate_executor_binder</span></code>
adapter. When a supported operation completes immediately (that is, within
the initiating function) the associated immmediate executor is obtained,
and the completion handler is delivered through that executor as if by
using <codeclass="computeroutput"><spanclass="identifier">asio</span><spanclass="special">::</span><spanclass="identifier">dispatch</span></code> on that executor. By default,
the immediate executor delivers the completion handler as if using <codeclass="computeroutput"><spanclass="identifier">asio</span><spanclass="special">::</span><spanclass="identifier">post</span></code> via the operation's I/O executor.
For example, to allow a recursive call to the completion handler of an
<br> Immediate execution is currently supported for asynchronous operations
on reactor-based sockets and descriptors, and for asynchronous operations
on channels.
</p>
</li>
<liclass="listitem">
<pclass="simpara">
Added user-defined literals for buffer types. The <codeclass="computeroutput"><spanclass="identifier">_buf</span></code>
literal suffix, defined in namespace <codeclass="computeroutput"><spanclass="identifier">asio</span><spanclass="special">::</span><spanclass="identifier">buffer_literals</span></code>,
may be used to create const_buffer objects from string, binary integer,
and hexadecimal integer literals. These buffer literals may be arbitrarily
long. For example:<br>
</p>
<preclass="programlisting"> using namespace asio::buffer_literals;
Added a new protocol type <codeclass="computeroutput"><spanclass="identifier">local</span><spanclass="special">::</span><spanclass="identifier">seq_packet_protocol</span></code>
to represent <codeclass="computeroutput"><spanclass="identifier">AF_UNIX</span></code> with
flags via optional argument to <codeclass="computeroutput"><spanclass="identifier">signal_set</span><spanclass="special">::</span><spanclass="identifier">add</span></code>.
When registering a signal, it is now possible to pass flags that specify
the behaviour associated with the signal. These flags are specified as
an enum type in a new class, signal_set_base, and are passed to the underlying
<br> Specifying flags other than <codeclass="computeroutput"><spanclass="identifier">flags</span><spanclass="special">::</span><spanclass="identifier">dont_care</span></code>
will fail unless <codeclass="computeroutput"><spanclass="identifier">sigaction</span><spanclass="special">()</span></code> is supported by the target operating
system. Since signal registration is global, conflicting flags (multiple
registrations that pass differing flags other than <codeclass="computeroutput"><spanclass="identifier">flags</span><spanclass="special">::</span><spanclass="identifier">dont_care</span></code>)
<codeclass="computeroutput"><spanclass="identifier">executor_binder</span></code>, and <codeclass="computeroutput"><spanclass="identifier">cancellation_slot_binder</span></code> to support detection
of unspecialised associators.
</li>
<liclass="listitem">
Fixed ambiguity in <codeclass="computeroutput"><spanclass="identifier">associated_cancellation_slot</span><spanclass="special"><</span><spanclass="identifier">reference_wrapper</span><spanclass="special">>::</span><spanclass="identifier">get</span><spanclass="special">()</span></code>.
for completion signatures containing <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">exception_ptr</span></code>.
Ensured buffered messages can still be received when an <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">channel</span></code>
is closed.
</li>
<liclass="listitem">
Fixed the <codeclass="computeroutput"><spanclass="identifier">any_completion_handler</span></code>
assignment operator to work correctly.
</li>
<liclass="listitem">
Constrained the constructor of the move-only class template <codeclass="computeroutput"><spanclass="identifier">any_completion_handler</span></code> to prevent accidental
Fixed <codeclass="computeroutput"><spanclass="identifier">spawn</span></code> and <codeclass="computeroutput"><spanclass="identifier">co_spawn</span></code> implementations to dispatch
cancellation handlers on the correct executor. When a completion handler
uses a specified (i.e. non-default) associated executor, cancellation handlers
are dispatched to the executor that was passed to <codeclass="computeroutput"><spanclass="identifier">spawn</span><spanclass="special">()</span></code> or <codeclass="computeroutput"><spanclass="identifier">co_spawn</span><spanclass="special">()</span></code>.
</li>
<liclass="listitem">
Fixed <codeclass="computeroutput"><spanclass="identifier">spawn</span></code> to ensure the
completion handler is dispatched through the correct executor.
</li>
<liclass="listitem">
Changed to use <codeclass="computeroutput"><spanclass="identifier">snprintf</span></code>
rather than <codeclass="computeroutput"><spanclass="identifier">sprintf</span></code> on
latest Xcode, to address deprecation warnings.
</li>
<liclass="listitem">
Fixed compatibility between <codeclass="computeroutput"><spanclass="identifier">co_spawn</span></code>
and <codeclass="computeroutput"><spanclass="identifier">any_completion_handler</span></code>.
</li>
<liclass="listitem">
Fixed the arguments passed to <codeclass="computeroutput"><spanclass="identifier">select_reactor</span><spanclass="special">::</span><spanclass="identifier">run</span></code>
when it is run on an internal thread.
</li>
<liclass="listitem">
Fixed compilation errors when <codeclass="computeroutput"><spanclass="special">(</span><spanclass="identifier">BOOST_</span><spanclass="special">)</span><spanclass="identifier">ASIO_DISABLE_SMALL_BLOCK_RECYCLING</span></code> is
defined.
</li>
<liclass="listitem">
Updated detection of C++20 coroutine support on clang 14 and later. This
includes the ability to use coroutines with libstdc++.
</li>
<liclass="listitem">
Changed standard library feature detection to always enable <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">invoke_result</span></code> when targeting C++17 or
later.
</li>
<liclass="listitem">
Fixed detection of return type deduction with MSVC.
</li>
<liclass="listitem">
Added a missing include in <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">coro</span></code>
implementation.
</li>
<liclass="listitem">
Updated the asynchronous operation requirements to relax the requirements
on the associated executor.
</li>
<liclass="listitem">
Added <codeclass="literal">io_uring</code> to the implementation notes.
Added <codeclass="computeroutput"><spanclass="identifier">any_completion_handler</span><spanclass="special"><></span></code>, which can be used to type-erase
completion handlers. A typical use case is to enable separate compilation
of asynchronous operation implementations. For example:<br>
Added <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">co_composed</span></code> which facilitates a lightweight
implementation of user-defined asynchronous operations using C++20 coroutines.
The following example illustrates a simple asynchronous operation that
implements an echo protocol in terms of a coroutine:<br>
Added nothrow constructor overloads to <codeclass="computeroutput"><spanclass="identifier">execution</span><spanclass="special">::</span><spanclass="identifier">any_executor</span><spanclass="special"><></span></code> and <codeclass="computeroutput"><spanclass="identifier">any_io_executor</span></code>.
</li>
<liclass="listitem">
Optimised representation of empty <codeclass="computeroutput"><spanclass="identifier">execution</span><spanclass="special">::</span><spanclass="identifier">any_executor</span></code>
objects to improve the performance of copy and move operations.
</li>
<liclass="listitem">
Added an <codeclass="computeroutput"><spanclass="identifier">associated_cancellation_slot</span></code>
specialisation for <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">reference_wrapper</span></code>.
</li>
<liclass="listitem">
Changed I/O objects to return their executors by const reference.
</li>
<liclass="listitem">
Changed associated to use deduced return types for all two-argument <codeclass="computeroutput"><spanclass="identifier">get</span></code> functions.
to catch unhandled exceptions and rethrow them outside of the spawned "thread".
</li>
<liclass="listitem">
Fixed cleanup of of terminal-state <codeclass="computeroutput"><spanclass="identifier">spawn</span></code>
"thread" objects.
</li>
<liclass="listitem">
Changed semantics of <codeclass="computeroutput"><spanclass="identifier">dispatch</span></code>
to mean the executor is used as-is. An execution context's default executor
is imbued with the possibly-blocking property.
</li>
<liclass="listitem">
Deprecated the <codeclass="computeroutput"><spanclass="identifier">execution</span><spanclass="special">::</span><spanclass="identifier">execute</span></code>
customisation point. Use <codeclass="computeroutput"><spanclass="identifier">execute</span></code>
as a member function.
</li>
<liclass="listitem">
Deprecated the concepts, traits, functions and customisation points related
to senders and receivers.
</li>
<liclass="listitem">
Added a C++11 <codeclass="computeroutput"><spanclass="identifier">parallel_group</span></code>
example.
</li>
<liclass="listitem">
Fixed example code to not use the deprecated conversion of a resolve result
to an endpoint.
</li>
<liclass="listitem">
Fixed an ambiguity in <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">channel_traits</span></code>
specialisations.
</li>
<liclass="listitem">
Added a specialised channel implementation for the for <codeclass="computeroutput"><spanclass="identifier">R</span><spanclass="special">(</span><spanclass="identifier">error_code</span><spanclass="special">)</span></code> signature.
</li>
<liclass="listitem">
Made <codeclass="computeroutput"><spanclass="identifier">cancelled</span><spanclass="special">()</span></code>
public on the <codeclass="computeroutput"><spanclass="identifier">async_compose</span></code>
'self' object.
</li>
<liclass="listitem">
Added io_executor_type and get_io_executor to the <codeclass="computeroutput"><spanclass="identifier">async_compose</span></code>
'self' object.
</li>
<liclass="listitem">
Fixed implementation of <codeclass="computeroutput"><spanclass="identifier">release</span><spanclass="special">()</span></code> for Windows overlapped handles.
</li>
<liclass="listitem">
Enabled deferred awaiting for <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">coro</span></code>,
and fixed allocator handling. This means that <codeclass="computeroutput"><spanclass="identifier">use_coro</span></code>
does not return a coro object, just like use_awaitable does, i.e. it's
an overhead that buys us type erasure. Allocators can now be set for <codeclass="computeroutput"><spanclass="identifier">coro</span></code> by including <codeclass="computeroutput"><spanclass="identifier">allocator_arg</span></code>
in the coro signature.
</li>
<liclass="listitem">
Cleaned up <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">promise</span></code>
and made it an asynchronous operation object.
</li>
<liclass="listitem">
Constrained <codeclass="computeroutput"><spanclass="identifier">post</span></code>/<codeclass="computeroutput"><spanclass="identifier">defer</span></code> overloads on ability to require
Changed descriptor implementation to fall back to <codeclass="computeroutput"><spanclass="identifier">fcntl</span></code>
if <codeclass="computeroutput"><spanclass="identifier">ioctl</span></code> fails with <codeclass="computeroutput"><spanclass="identifier">ENOTTY</span></code> when setting non-blocking mode.
Improved the performance of <codeclass="computeroutput"><spanclass="identifier">awaitable</span><spanclass="special"><></span></code>-based coroutines when they directly
<codeclass="computeroutput"><spanclass="identifier">co_await</span></code> an asynchronous
operation, by eliminating the copy of the operation object in <codeclass="computeroutput"><spanclass="identifier">await_transform</span></code>.
</li>
<liclass="listitem">
Improved the performance of <codeclass="computeroutput"><spanclass="identifier">spawn</span><spanclass="special">()</span></code>-based stackful coroutines by storing
a reference to the yield context in the completion handler, rather than
storing a copy of the executor.
</li>
<liclass="listitem">
Fixed a C++03 build error by disabling <codeclass="computeroutput"><spanclass="identifier">index_sequence</span></code>
emulation when variadic templates are unavailable.
</li>
<liclass="listitem">
Fixed detection of <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">aligned_alloc</span></code>
for older Apple platforms.
</li>
<liclass="listitem">
Removed faulty assertions from <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">coro</span></code>
implementation.
</li>
<liclass="listitem">
Added defence against Qt-defined macros when building with Intel C++.
</li>
<liclass="listitem">
Ensured that a <codeclass="computeroutput"><spanclass="identifier">spawn</span><spanclass="special">()</span></code>-based
stackful coroutine is cleaned up immediately after it completes.
</li>
<liclass="listitem">
Changed the implementation of the <codeclass="computeroutput"><spanclass="identifier">select_reactor</span></code>,
on Windows, to ensure that any exception resulting from failure to recreate
its interrupter's sockets will be allowed to propagate out through <codeclass="computeroutput"><spanclass="identifier">io_context</span><spanclass="special">::</span><spanclass="identifier">run</span><spanclass="special">()</span></code>.
</li>
<liclass="listitem">
Changed the MSVC version used for the <codeclass="computeroutput"><spanclass="identifier">system_error</span></code>
workaround, as more recent runtime redistributables appear to have fixed
the issue.
</li>
<liclass="listitem">
Changed the <codeclass="computeroutput"><spanclass="identifier">async_compose</span></code>
example to use a return type compatible with the new <codeclass="computeroutput"><spanclass="identifier">async_result</span></code>
Added a deduced trailing return type, using <codeclass="computeroutput"><spanclass="keyword">decltype</span></code>,
to all asynchronous operations' initiating functions when using C++11.
This change enables the new form of <codeclass="computeroutput"><spanclass="identifier">async_result</span></code>,
where the return type can vary per operation, for C++11.
</li>
<liclass="listitem">
Moved <codeclass="computeroutput"><spanclass="identifier">append</span></code>, <codeclass="computeroutput"><spanclass="identifier">prepend</span></code>, <codeclass="computeroutput"><spanclass="identifier">as_tuple</span></code>,
and <codeclass="computeroutput"><spanclass="identifier">deferred</span></code> to the <codeclass="computeroutput"><spanclass="identifier">asio</span></code> namespace, and made them compatible
with C++11. These are no longer experimental facilities, although the names
have temporarily been retained under the <codeclass="computeroutput"><spanclass="identifier">asio</span><spanclass="special">::</span><spanclass="identifier">experimental</span></code>
overloads for contiguous containers, such as <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">span</span></code>.
</li>
<liclass="listitem">
<pclass="simpara">
Added the ability for <codeclass="computeroutput"><spanclass="identifier">awaitable</span><spanclass="special"><></span></code>-based coroutines to directly <codeclass="computeroutput"><spanclass="identifier">co_await</span></code> operations that are packaged
as function objects. For example, using <codeclass="computeroutput"><spanclass="identifier">deferred</span></code>:<br>
member functions to pipes, Windows stream handles, and Windows random-access
handles.
</li>
<liclass="listitem">
Enabled support for <codeclass="computeroutput"><spanclass="identifier">Endpoint</span></code>
implementations that return <codeclass="computeroutput"><spanclass="keyword">void</span></code>
pointers from their <codeclass="computeroutput"><spanclass="identifier">data</span><spanclass="special">()</span></code> member functions, as per the documented
<codeclass="computeroutput"><spanclass="identifier">Endpoint</span></code> type requirements.
and <codeclass="computeroutput"><spanclass="identifier">race</span><spanclass="special">()</span></code>
from <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">promise</span></code>, as <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">parallel_group</span></code>
covers this functionality.
</li>
<liclass="listitem">
Added source locations to exceptions and error codes produced by the synchronous
and asynchronous operations.
</li>
<liclass="listitem">
Fixed compatibility with OpenSSL 3.0.4 and later.
</li>
<liclass="listitem">
Fixed compatibility with with <codeclass="literal">-masm=intel</code>.
</li>
<liclass="listitem">
Explicitly stated that socket <codeclass="computeroutput"><spanclass="identifier">shutdown</span><spanclass="special">()</span></code> calls are thread-safe with respect to
certain other synchronous operations on the same socket.
</li>
<liclass="listitem">
Optimised the move construction of I/O objects where only the executor
type differs.
</li>
<liclass="listitem">
Fixed the detection of <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">invoke_result</span></code>
for clang/libc++.
</li>
<liclass="listitem">
Fixed an issue where <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">parallel_group</span></code>
initiation incorrectly moved arguments instead of forwarding them.
</li>
<liclass="listitem">
Fixed a sequencing issue in the implementation of <codeclass="computeroutput"><spanclass="identifier">post</span><spanclass="special">()</span></code>, <codeclass="computeroutput"><spanclass="identifier">dispatch</span><spanclass="special">()</span></code>, and <codeclass="computeroutput"><spanclass="identifier">defer</span><spanclass="special">()</span></code>, where the the associated allocator may
be obtained from an already moved-from completion handler.
</li>
<liclass="listitem">
Fixed the <codeclass="computeroutput"><spanclass="identifier">awaitable</span><spanclass="special"><></span></code>
implementation to propagate exceptions from awaited initiation functions
through the current completion handler.
</li>
<liclass="listitem">
Fixed detection of <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">aligned_alloc</span></code>
with <codeclass="literal">gcc</code>.
</li>
<liclass="listitem">
Changed to avoid using the soon-to-be-deprecated <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">aligned_storage</span></code>
on newer compilers.
</li>
<liclass="listitem">
Fixed various compiler warnings.
</li>
<liclass="listitem">
Updated all composed operations examples, and the C++11 timeouts example,
to use the new <codeclass="computeroutput"><spanclass="identifier">async_result</span></code>
form.
</li>
<liclass="listitem">
Added composed operation and coroutine examples for C++20.
and <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">basic_concurrent_channel</span><spanclass="special">::</span><spanclass="identifier">reset</span><spanclass="special">()</span></code>
so that they work correctly for an unclosed channel.
</li>
<liclass="listitem">
Fixed potential undefined behaviour in the <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">promise</span></code>
and <codeclass="computeroutput"><spanclass="identifier">all</span><spanclass="special">()</span></code>.
</li>
<liclass="listitem">
Changed the <codeclass="computeroutput"><spanclass="identifier">co_spawn</span></code> implementation
to explicitly dispatch cancellation signals through the specified executor,
if the the completion handler has an associated executor of its own.
</li>
<liclass="listitem">
Added more detailed reference documentation to <codeclass="computeroutput"><spanclass="identifier">make_strand</span><spanclass="special">()</span></code>, <codeclass="computeroutput"><spanclass="identifier">make_work_guard</span><spanclass="special">()</span></code>, <codeclass="computeroutput"><spanclass="identifier">ip</span><spanclass="special">::</span><spanclass="identifier">address_v4</span></code>,
and <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">basic_concurrent_channel</span></code>.
</li>
<liclass="listitem">
Re-arranged and extended the Overview documentation to cover files, pipes,
<codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">promise</span></code>, channels, and completion token
adapters.
</li>
<liclass="listitem">
Reverted the <codeclass="computeroutput"><spanclass="identifier">io_context</span></code>
reference documentation to use <codeclass="computeroutput"><spanclass="identifier">executor_work_guard</span></code>
when preventing the <codeclass="computeroutput"><spanclass="identifier">io_context</span></code>
from running out of work.
</li>
<liclass="listitem">
Removed references to <codeclass="computeroutput"><spanclass="identifier">deadline_timer</span></code>
from the Overview documentation.
</li>
<liclass="listitem">
Added reference documentation cross-references to asynchronous model elements.
Added <codeclass="computeroutput"><spanclass="identifier">bind_allocator</span></code>, to
simplify associating a custom allocator with a completion token or handler.
</li>
<liclass="listitem">
Added the <codeclass="computeroutput"><spanclass="identifier">file_base</span><spanclass="special">::</span><spanclass="identifier">sync_all_on_write</span></code> flag, which maps to
<codeclass="computeroutput"><spanclass="identifier">O_SYNC</span></code> on POSIX and <codeclass="computeroutput"><spanclass="identifier">FILE_FLAG_WRITE_THROUGH</span></code> on Windows.
</li>
<liclass="listitem">
Added missing implementation of <codeclass="computeroutput"><spanclass="identifier">basic_file</span><spanclass="special">::</span><spanclass="identifier">release</span><spanclass="special">()</span></code>.
</li>
<liclass="listitem">
Added per-operation cancellation support to signal sets.
Added compatibility with OpenSSL 3.0, particularly when deprecated functionality
is disabled.
</li>
<liclass="listitem">
Added support for adopting an existing <codeclass="computeroutput"><spanclass="identifier">SSL</span><spanclass="special">*</span></code> into an <codeclass="computeroutput"><spanclass="identifier">ssl</span><spanclass="special">::</span><spanclass="identifier">stream</span><spanclass="special"><></span></code>.
</li>
<liclass="listitem">
Enabled <codeclass="computeroutput"><spanclass="identifier">executor_work_guard</span><spanclass="special"><></span></code> even when <codeclass="computeroutput"><spanclass="identifier">ASIO_NO_TS_EXECUTORS</span></code>
is defined.
</li>
<liclass="listitem">
Enabled movable socket iostreams when using clang.
for <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">append</span></code> and <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">prepend</span></code>,
to correctly propagate the associated allocator, executor, and cancellation
slot.
</li>
<liclass="listitem">
Fixed 'zero as null pointer constant' warning in C++20 coroutines implementation
of <codeclass="computeroutput"><spanclass="identifier">awaitable</span></code>.
</li>
<liclass="listitem">
Ensured concurrency hint preprocessor macros are made available when <codeclass="literal">asio/io_context.hpp</code>
is included.
</li>
<liclass="listitem">
Fixed issue where the primary <codeclass="computeroutput"><spanclass="identifier">associated_allocator</span></code>
template was not correctly detecting the nested <codeclass="computeroutput"><spanclass="identifier">T</span><spanclass="special">::</span><spanclass="identifier">allocator_type</span></code>.
</li>
<liclass="listitem">
Fixed <codeclass="literal">io_uring</code> implementation of <codeclass="computeroutput"><spanclass="identifier">async_receive_from</span></code>
operation for sockets.
</li>
<liclass="listitem">
Fixed <codeclass="literal">io_uring</code> implementation of <codeclass="computeroutput"><spanclass="identifier">write_some_at</span></code>
operation for files.
</li>
<liclass="listitem">
Changed <codeclass="literal">io_uring</code> implementation to correctly check that
it is not the default before registering with reactor.
</li>
<liclass="listitem">
Fixed a circular inclusion issue when using <codeclass="literal">io_uring</code>
in some build configurations.
</li>
<liclass="listitem">
Fixed <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">coro</span></code>'s per-operation cancellation to
clear the slot at completion of each operation.
</li>
<liclass="listitem">
Fixed memory management in <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">promise</span></code>'s
implementation for <codeclass="computeroutput"><spanclass="identifier">ssl</span><spanclass="special">::</span><spanclass="identifier">stream</span></code>.
to work when both <codeclass="computeroutput"><spanclass="identifier">ASIO_USE_TS_EXECUTOR_AS_DEFAULT</span></code>
and <codeclass="computeroutput"><spanclass="identifier">ASIO_SEPARATE_COMPILATION</span></code>
are defined.
</li>
<liclass="listitem">
Fixed implementation of <codeclass="computeroutput"><spanclass="identifier">basic_socket</span><spanclass="special">::</span><spanclass="identifier">at_mark</span><spanclass="special">()</span></code> when using the <codeclass="computeroutput"><spanclass="identifier">sockatmark</span><spanclass="special">()</span></code> system call.
</li>
<liclass="listitem">
Changed the recycling allocator to use the default alignment as the minimum
alignment for allocations.
</li>
<liclass="listitem">
Added additional standard header file includes, as required by newer compilers.
</li>
<liclass="listitem">
Added a workaround for apparent coroutine codegen bug with Apple's clang.
</li>
<liclass="listitem">
Fixed various warnings in the examples and unit tests.
</li>
<liclass="listitem">
Added a C++11 example showing file descriptor passing over local sockets.
Thanks to Heiko Hund for providing this example.
</li>
<liclass="listitem">
Added C++14 examples of wrapping callback-based APIs in asynchronous operations.
</li>
<liclass="listitem">
Added an overview of Asio's asynchronous model to the documentation.
</li>
<liclass="listitem">
Reworked reference documentation in terms of completion tokens.
</li>
<liclass="listitem">
Updated documentation of asynchronous operation requirements to use new
completion token form.
</li>
<liclass="listitem">
Updated documentation for <codeclass="computeroutput"><spanclass="identifier">dispatch</span><spanclass="special">()</span></code>, <codeclass="computeroutput"><spanclass="identifier">post</span><spanclass="special">()</span></code>, and <codeclass="computeroutput"><spanclass="identifier">defer</span><spanclass="special">()</span></code> to cover both the old and new executor
forms.
</li>
<liclass="listitem">
Documented per-operation cancellation for serial ports.
</li>
<liclass="listitem">
Clarified the non-concurrency guarantees made for allocators.
Fixed build errors when <codeclass="computeroutput"><spanclass="identifier">ASIO_USE_TS_EXECUTOR_AS_DEFAULT</span></code>
is defined.
</li>
<liclass="listitem">
Fixed corruption, cleanup issues in channel implementation.
</li>
<liclass="listitem">
Added missing move assignment operator to <codeclass="computeroutput"><spanclass="identifier">awaitable</span><spanclass="special"><></span></code>.
</li>
<liclass="listitem">
Fixed an access violation when using coroutines with MSVC, due to incorrect
alignment of allocated memory.
</li>
<liclass="listitem">
Fixed a cleanup issue in <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">parallel_group</span></code>
that occured when the execution context was shut down with parallel operations
still pending.
</li>
<liclass="listitem">
Fixed header inclusion order problem when io_uring is enabled.
</li>
<liclass="listitem">
Eliminated <codeclass="computeroutput"><spanclass="identifier">shared_ptr</span></code> use
from <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">coro</span></code><codeclass="computeroutput"><spanclass="identifier">co_spawn</span><spanclass="special">()</span></code> implementation.
from being called on <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">coro</span></code>
temporaries.
</li>
<liclass="listitem">
Made <codeclass="computeroutput"><spanclass="identifier">awaitable_operators</span><spanclass="special">.</span><spanclass="identifier">hpp</span></code>
header self-contained.
</li>
<liclass="listitem">
Added clarifications to the documentation on concurrency hints.
</li>
<liclass="listitem">
Added documentation on error handling techniques for C++20 coroutines.
Added an io_uring backend. This backend may be used for all I/O objects,
including sockets, timers, and posix descriptors.<br><br> The backend
is disabled by default, and must be enabled by defining both <codeclass="computeroutput"><spanclass="identifier">ASIO_HAS_IO_URING</span></code> and <codeclass="computeroutput"><spanclass="identifier">ASIO_DISABLE_EPOLL</span></code>.<br>
alone will enable the backend without using it for the existing I/O objects.
This allows it to be used for I/O objects that require io_uring support,
such as files.<br><br> This support depends on the <codeclass="literal">liburing</code>
library at both compile and link time. Add <codeclass="computeroutput"><spanclass="special">-</span><spanclass="identifier">luring</span></code> to your list of libraries for
linking.
</li>
<liclass="listitem">
<pclass="simpara">
Added support for files. This introduces new classes for stream-oriented
and random-access files. For example, to write to a newly created stream-oriented
<br> Buffer registration supports the io_uring backend when used with
read and write operations on descriptors, files, pipes, and sockets. For
portability, the facility may be used on other platforms, but the registered
buffers will behave as normal buffers.
</p>
</li>
<liclass="listitem">
<pclass="simpara">
Added experimental support for channels. This adds templates <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">basic_channel</span></code> and <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">basic_concurrent_channel</span></code>,
with aliases <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">channel</span></code>
and <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">concurrent_channel</span></code>. Channels may be used
to send completions as messages. For example:<br>
</p>
<preclass="programlisting"><spanclass="comment">// Create a channel with no buffer space.</span>
Implemented improvements to <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">coro</span></code>.
on <codeclass="literal">clang</code> when using an MSVC runtime.
</li>
<liclass="listitem">
Changed to use a faster implementation for <codeclass="computeroutput"><spanclass="identifier">ip</span><spanclass="special">::</span><spanclass="identifier">network_v4</span><spanclass="special">::</span><spanclass="identifier">canonical</span><spanclass="special">()</span></code>.
</li>
<liclass="listitem">
Added template specialisations for common uses to improve compile time.
</li>
<liclass="listitem">
Reduced the size of <codeclass="computeroutput"><spanclass="identifier">io_context</span></code>
executors to a single pointer.
</li>
<liclass="listitem">
Increased the small object buffer size for <codeclass="computeroutput"><spanclass="identifier">execution</span><spanclass="special">::</span><spanclass="identifier">any_executor</span></code>
and <codeclass="computeroutput"><spanclass="identifier">any_io_executor</span></code>.
</li>
<liclass="listitem">
Fixed multi-signature handling when variadic templates are disabled.
</li>
<liclass="listitem">
Fixed compatibility with new versions of <codeclass="literal">gcc</code> and <codeclass="literal">clang</code>.
</li>
<liclass="listitem">
Fixed compilation on Solaris.
</li>
<liclass="listitem">
Fix defence against Qt-defined macros when building with MSVC.
Fixed <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">coro</span></code> compatibility with <codeclass="literal">gcc</code>.
</li>
<liclass="listitem">
Fixed <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">promise</span></code> compatibility with <codeclass="literal">gcc</code>.
</li>
<liclass="listitem">
Added documentation for per-operation cancellation.
</li>
<liclass="listitem">
Added documentation for <codeclass="computeroutput"><spanclass="identifier">parallel_group</span></code>.
</li>
<liclass="listitem">
Added overview documentation for <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">coro</span></code>.
Fixed argument evaluation order issue with a potentially moved-from variable
in <codeclass="computeroutput"><spanclass="identifier">awaitable</span></code> implementation.
</li>
<liclass="listitem">
Enabled "expression SFINAE" for recent MSVC using <codeclass="computeroutput"><spanclass="special">/</span><spanclass="identifier">std</span><spanclass="special">:</span><spanclass="identifier">c</span><spanclass="special">++</span><spanclass="identifier">latest</span></code>.
</li>
<liclass="listitem">
Fixed compilation errors when <codeclass="computeroutput"><spanclass="identifier">dev_poll_reactor</span></code>
backend is used.
</li>
<liclass="listitem">
Fixed handler type requirements checking to reflect rvalue completion handler
Fixed handling of move-only results with awaitable operators <codeclass="computeroutput"><spanclass="special">&&</span></code> and <codeclass="computeroutput"><spanclass="special">||</span></code>.
Added support for cancellation of individual asynchronous operations. Cancellation
is implemented by having each completion handler carry an associated <codeclass="computeroutput"><spanclass="identifier">CancellationSlot</span></code>, a lightweight cancellation
channel that is specified through the new <codeclass="computeroutput"><spanclass="identifier">associated_cancellation_slot</span></code>
associator. A concrete <codeclass="computeroutput"><spanclass="identifier">CancellationSlot</span></code>
implementation is provided in the form of the <codeclass="computeroutput"><spanclass="identifier">cancellation_signal</span></code>
and <codeclass="computeroutput"><spanclass="identifier">cancellation_slot</span></code> classes.
In conjunction with the <codeclass="computeroutput"><spanclass="identifier">bind_cancellation_slot</span></code>
helper function, these may be used to hook cancellation into asynchronous
operations. However, it should be noted that these classes are the low-level
building blocks of cancellation, and most use cases should use a higher
level abstraction for cancellation, such as <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">parallel_group</span></code>
or the new logical operators for <codeclass="computeroutput"><spanclass="identifier">awaitable</span></code>
(see below). The ability to cancel individual operations, or composed operations,
all Asio-provided composed operations such as <codeclass="computeroutput"><spanclass="identifier">async_read</span></code>
and <codeclass="computeroutput"><spanclass="identifier">async_write</span></code>
</li>
<liclass="listitem">
compositions based on <codeclass="computeroutput"><spanclass="identifier">async_compose</span></code>
</li>
<liclass="listitem">
C++20 coroutines that use <codeclass="computeroutput"><spanclass="identifier">awaitable</span></code>
</li>
<liclass="listitem">
C++20 coroutines that use the new <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">coro</span></code>
(see below)
</li>
<liclass="listitem">
the new <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">parallel_group</span></code>
operation (see below)
</li>
<liclass="listitem">
the new <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">promise</span></code>
class (see below)
</li>
</ul></div>
</li>
<liclass="listitem">
<pclass="simpara">
Added the <codeclass="computeroutput"><spanclass="identifier">associator</span></code> trait.
The <codeclass="computeroutput"><spanclass="identifier">associator</span></code> trait is
used to generically forward associators, such as <codeclass="computeroutput"><spanclass="identifier">associated_executor</span></code>
and <codeclass="computeroutput"><spanclass="identifier">associated_allocator</span></code>,
through intermediate completion handlers. For example:<br>
<br> and then bringing the contents of the <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">awaitable_operators</span></code>
Added the <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">as_tuple</span></code>
completion token adapter. The <codeclass="computeroutput"><spanclass="identifier">as_tuple</span></code>
completion token adapter can be used to specify that the completion handler
arguments should be combined into a single tuple argument. The <codeclass="computeroutput"><spanclass="identifier">as_tuple</span></code> adapter may be used in conjunction
with <codeclass="computeroutput"><spanclass="identifier">use_awaitable</span></code> and
Added the <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">append</span></code>
completion token adapter. The <codeclass="computeroutput"><spanclass="identifier">append</span></code>
completion token adapter can be used to pass additional completion handler
arguments at the end of the completion signature. For example:<br>
Added the <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">prepend</span></code>
completion token adapter. The <codeclass="computeroutput"><spanclass="identifier">prepend</span></code>
completion token adapter can be used to pass additional arguments before
the existing completion handler arguments. For example:<br>
Added the <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">deferred</span></code>
completion token. The <codeclass="computeroutput"><spanclass="identifier">deferred</span></code>
completion token takes a call to an asynchronous operation's initiating
function and turns it into a function object that accepts a completion
Added the <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">parallel_group</span></code>
class and <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">make_parallel_group</span></code>
function. This utility may be used to launch work that is performed in
parallel, and wait for one or all of the operations to complete. A <codeclass="computeroutput"><spanclass="identifier">parallel_group</span></code> implements automatic cancellation
<br> The conditions for completion of the group may be specified using
one of the four provided function objects <codeclass="computeroutput"><spanclass="identifier">wait_for_all</span></code>,
<codeclass="computeroutput"><spanclass="identifier">wait_for_one</span></code>, <codeclass="computeroutput"><spanclass="identifier">wait_for_one_success</span></code>, and <codeclass="computeroutput"><spanclass="identifier">wait_for_one_error</span></code>, or with a custom
function. The <codeclass="computeroutput"><spanclass="identifier">parallel_group</span></code>
class can also be combined with <codeclass="computeroutput"><spanclass="identifier">deferred</span></code>
<br> Note: for maximum flexibility, <codeclass="computeroutput"><spanclass="identifier">parallel_group</span></code>
does not propagate the executor automatically to the operations within
the group.
</p>
</li>
<liclass="listitem">
<pclass="simpara">
Added <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">promise</span></code>. The <codeclass="computeroutput"><spanclass="identifier">promise</span></code>
type allows eager execution and synchronisation of async operations. For
<spanclass="identifier">promise</span><spanclass="special">.</span><spanclass="identifier">async_wait</span><spanclass="special">(</span><spanclass="comment">// completion the operation</span>
<spanclass="keyword">else</span><spanclass="keyword">if</span><spanclass="special">(</span><spanclass="identifier">v</span><spanclass="special">.</span><spanclass="identifier">index</span><spanclass="special">()</span><spanclass="special">==</span><spanclass="number">1</span><spanclass="special">)</span><spanclass="comment">// completed in time</span>
<br> Thanks go to Klemens Morgenstern for contributing this feature.
</p>
</li>
<liclass="listitem">
<pclass="simpara">
Added the <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">coro</span></code>
class template. The <codeclass="computeroutput"><spanclass="identifier">coro</span></code>
type is a C++20 coroutine primitive for resumable functions, with the ability
to combine both asynchronous waiting (<codeclass="computeroutput"><spanclass="identifier">co_await</span></code>)
and yielding (<codeclass="computeroutput"><spanclass="identifier">co_yield</span></code>)
into a single, stateful control flow. For example:<br>
<br> Thanks go to Klemens Morgenstern for contributing this feature.
</p>
</li>
<liclass="listitem">
Added move assignment to <codeclass="computeroutput"><spanclass="identifier">ssl</span><spanclass="special">::</span><spanclass="identifier">stream</span><spanclass="special"><></span></code>.
</li>
<liclass="listitem">
Changed <codeclass="computeroutput"><spanclass="identifier">co_spawn</span></code> to <codeclass="computeroutput"><spanclass="identifier">dispatch</span></code> the coroutine's initial step
to the executor, and to only <codeclass="computeroutput"><spanclass="identifier">post</span></code>
the completion handler if the coroutine did not otherwise perform a context
switch (i.e. a <codeclass="computeroutput"><spanclass="identifier">co_await</span></code>
on an asynchronous operation).
</li>
<liclass="listitem">
Enabled additional optimisations for <codeclass="computeroutput"><spanclass="identifier">any_executor</span></code>
and <codeclass="computeroutput"><spanclass="identifier">any_io_executor</span></code> when
used with asynchronous operations.
</li>
<liclass="listitem">
Added the <codeclass="computeroutput"><spanclass="identifier">nodiscard</span></code> attribute
to <codeclass="computeroutput"><spanclass="identifier">awaitable</span><spanclass="special"><></span></code>.
</li>
<liclass="listitem">
Increased the number of cached slots in the default recycling allocator.
This number defaults to 2, but may also be specified by defining the <codeclass="computeroutput"><spanclass="identifier">ASIO_RECYCLING_ALLOCATOR_CACHE_SIZE</span></code> macro.
</li>
<liclass="listitem">
Disabled the <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">system_error</span></code> message workaround for recent
MSVC.
</li>
<liclass="listitem">
Changed the default allocator behaviour to respect alignment requirements,
to support over-aligned types. Requires C++17 or later, or Boost.
</li>
<liclass="listitem">
Ensured the result strings are always initialised in reverse name resolution.
</li>
<liclass="listitem">
Fixed recursive template instantiation issues in <codeclass="computeroutput"><spanclass="identifier">use_awaitable_t</span><spanclass="special">::</span><spanclass="identifier">executor_with_default</span></code>.
</li>
<liclass="listitem">
Fixed the <codeclass="computeroutput"><spanclass="identifier">any_io_executor</span></code>
equality operators to correctly return a result based on the target executor.
Added <codeclass="computeroutput"><spanclass="identifier">ip</span><spanclass="special">::</span><spanclass="identifier">scope_id_type</span></code> type alias.
</li>
<liclass="listitem">
Added <codeclass="computeroutput"><spanclass="identifier">ip</span><spanclass="special">::</span><spanclass="identifier">port_type</span></code> type alias.
</li>
<liclass="listitem">
Added <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">hash</span></code> specialisations for IP addresses.
</li>
<liclass="listitem">
Added <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">hash</span></code> specialisations for <codeclass="computeroutput"><spanclass="identifier">ip</span><spanclass="special">::</span><spanclass="identifier">basic_endpoint</span><spanclass="special"><></span></code>.
</li>
<liclass="listitem">
Refactored SFINAE usage to improve compile times.
</li>
<liclass="listitem">
Added friendship support to customisation points, and made most customisations
Fixed <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">as_single</span></code> to work with handler hook deprecation.
</li>
<liclass="listitem">
Ensured pthread condition variable attributes are cleaned up on all platforms.
</li>
<liclass="listitem">
Clarified thread safety notes on sockets and descriptors.
</li>
<liclass="listitem">
Ensured <codeclass="computeroutput"><spanclass="identifier">errno</span></code> is not overwritten
if <codeclass="computeroutput"><spanclass="identifier">socket</span><spanclass="special">()</span></code>
fails on macOS/FreeBSD.
</li>
<liclass="listitem">
Fixed work tracking for <codeclass="computeroutput"><spanclass="identifier">io_context</span></code>
and <codeclass="computeroutput"><spanclass="identifier">thread_pool</span></code> executors
objects are accessed only from implementation files.
</li>
<liclass="listitem">
Fixed I/O object move-assignment to ensure the executor is left in a valid
state.
</li>
<liclass="listitem">
Fixed detection of compiler support for defaulted template argument on
functions with MSVC.
</li>
<liclass="listitem">
Prevented the <codeclass="computeroutput"><spanclass="identifier">blocking</span><spanclass="special">.</span><spanclass="identifier">always</span></code>
property from being used with <codeclass="computeroutput"><spanclass="identifier">strand</span><spanclass="special"><></span></code>, as it did not produce the correct
Enabled support for UNIX domain sockets on Windows. From Windows 10, UNIX
domain sockets (a.k.a "local" sockets) are supported on Windows,
with the exception of the <codeclass="computeroutput"><spanclass="identifier">connect_pair</span></code>
function (which will fail with an operation_not_supported error).
</li>
<liclass="listitem">
Added executor-converting construction and assignment to <codeclass="computeroutput"><spanclass="identifier">ip</span><spanclass="special">::</span><spanclass="identifier">basic_resolver</span></code>.
</li>
<liclass="listitem">
Added compatibility between polymorphic executors and the (deprecated)
handler invocation hook.
</li>
<liclass="listitem">
<pclass="simpara">
Added the <codeclass="computeroutput"><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">as_single</span></code>
completion token adapter. The <codeclass="computeroutput"><spanclass="identifier">as_single</span></code>
completion token adapter can be used to specify that the completion handler
arguments should be combined into a single argument. For completion signatures
with a single parameter, the argument is passed through as-is. For signatures
with two or more parameters, the arguments are combined into a tuple. The
<codeclass="computeroutput"><spanclass="identifier">as_single</span></code> adapter may be
used in conjunction with <codeclass="computeroutput"><spanclass="identifier">use_awaitable</span></code>
Added support for <codeclass="computeroutput"><spanclass="identifier">MSG_NOSIGNAL</span></code>
on more platforms by using <codeclass="computeroutput"><spanclass="identifier">_POSIX_VERSION</span></code>
to detect whether it is supported.
</li>
<liclass="listitem">
Added the ability to compile using libpthread on Windows.
</li>
<liclass="listitem">
Added workarounds for the Intel C++ compiler.
</li>
<liclass="listitem">
Added more support for detecting and optimising for handlers that have
no custom executor.
</li>
<liclass="listitem">
Reduced lock contention for timer cancellation on Windows.
</li>
<liclass="listitem">
Reinstated a previously removed null-pointer check, as it had a measurable
impact on performance.
</li>
<liclass="listitem">
Fixed the <codeclass="computeroutput"><spanclass="identifier">executor</span></code> concept
to test for a const-qualified <codeclass="computeroutput"><spanclass="identifier">execute</span><spanclass="special">()</span></code>.
</li>
<liclass="listitem">
Fixed <codeclass="computeroutput"><spanclass="identifier">any_executor</span></code> support
for builds without RTTI support.
</li>
<liclass="listitem">
Fixed the <codeclass="computeroutput"><spanclass="identifier">thread_pool</span></code> unit
test to work without RTTI support.
</li>
<liclass="listitem">
Fixed C++20 coroutines compatibility with clang on Windows.
</li>
<liclass="listitem">
Fixed some compatibility issues with Windows Runtime.
</li>
<liclass="listitem">
Fixed shadow name warnings caused by addition of <codeclass="computeroutput"><spanclass="identifier">asio</span><spanclass="special">::</span><spanclass="identifier">query</span></code>.
</li>
<liclass="listitem">
Fixed a "logical ‘or’ of equal expressions" warning on linux.
Marked the <codeclass="computeroutput"><spanclass="identifier">basic_socket_acceptor</span></code>
move constructor as <codeclass="computeroutput"><spanclass="keyword">noexcept</span></code>.
</li>
<liclass="listitem">
Added workarounds for various issues in <codeclass="literal">gcc</code> 10's coroutine
support.
</li>
<liclass="listitem">
Added standard executor support to <codeclass="computeroutput"><spanclass="identifier">windows</span><spanclass="special">::</span><spanclass="identifier">overlapped_ptr</span></code>.
</li>
<liclass="listitem">
Added missing compatibility macros for the <codeclass="computeroutput"><spanclass="identifier">execution</span><spanclass="special">::</span><spanclass="identifier">receiver_of</span></code>
concept.
</li>
<liclass="listitem">
Added short-circuited evaluation to <codeclass="computeroutput"><spanclass="identifier">execution</span><spanclass="special">::</span><spanclass="identifier">executor</span></code>,
and <codeclass="computeroutput"><spanclass="identifier">execution</span><spanclass="special">::</span><spanclass="identifier">scheduler</span></code> concepts and the corresponding
traits. These now test first for well-formed CPO expressions (or, in the
case of senders, a specialised <codeclass="computeroutput"><spanclass="identifier">sender_traits</span></code>
template) and, if not valid, short-circuit the remainder of the evaluation.
This helps prevent recursive template instantiations that can occur in
some contexts.
</li>
<liclass="listitem">
Added constraints to the <codeclass="computeroutput"><spanclass="identifier">strand</span></code>
template's constructor, to prevent template instantiation recursion.
</li>
<liclass="listitem">
Changed Asio's internal executor adapters to prevent template instantiation
recursion.
</li>
<liclass="listitem">
Added constraints to the <codeclass="computeroutput"><spanclass="identifier">execution</span><spanclass="special">::</span><spanclass="identifier">any_executor</span></code>
template's converting constructors, as per the specification.
specialisation and <codeclass="computeroutput"><spanclass="identifier">connect</span><spanclass="special">()</span></code> member function to the <codeclass="computeroutput"><spanclass="identifier">thread_pool</span></code> executor, as per the specification.
</li>
<liclass="listitem">
Changed <codeclass="computeroutput"><spanclass="identifier">execution</span><spanclass="special">::</span><spanclass="identifier">blocking_t</span><spanclass="special">::</span><spanclass="identifier">always_t</span><spanclass="special">::</span><spanclass="identifier">is_preferable</span></code> to be false as per the
specification.
</li>
<liclass="listitem">
Added <codeclass="computeroutput"><spanclass="identifier">shape_type</span></code> and <codeclass="computeroutput"><spanclass="identifier">index_type</span></code> to <codeclass="computeroutput"><spanclass="identifier">thread_pool</span></code>
executors, as per the specification.
</li>
<liclass="listitem">
Ensured that the standard executor concept-related traits (such as <codeclass="computeroutput"><spanclass="identifier">execution</span><spanclass="special">::</span><spanclass="identifier">is_executor</span></code>) work with <codeclass="computeroutput"><spanclass="keyword">void</span></code>.
</li>
<liclass="listitem">
Fixed <codeclass="computeroutput"><spanclass="identifier">async_compose</span></code> support
for standard executors.
</li>
<liclass="listitem">
Fixed the forward declaration of <codeclass="computeroutput"><spanclass="identifier">any_io_executor</span></code>
in <codeclass="literal">asio/ts/netfwd.hpp</code>.
<codeclass="computeroutput"><spanclass="identifier">system_executor</span></code>, and <codeclass="computeroutput"><spanclass="identifier">strand</span><spanclass="special"><></span></code>.
</li>
<liclass="listitem">
Changed introductory documentation to reflect that there our now multiple
types of I/O execution context.
</li>
<liclass="listitem">
Marked constructors, destructors, and static data members in class synopses
The <codeclass="computeroutput"><spanclass="identifier">io_context</span><spanclass="special">::</span><spanclass="identifier">executor_type</span></code>, <codeclass="computeroutput"><spanclass="identifier">thread_pool</span><spanclass="special">::</span><spanclass="identifier">executor_type</span></code>,
<codeclass="computeroutput"><spanclass="identifier">async_compose</span></code>, <codeclass="computeroutput"><spanclass="identifier">use_future</span></code>, etc., can interoperate
with both new proposed standard executors, and with existing Networking
TS executors. The implementation determines at compile time which
model a particular executor meets; the proposed standard executor
model is used in preference if both are detected.
</li>
<liclass="listitem">
The <codeclass="computeroutput"><spanclass="identifier">any_io_executor</span></code>
type alias has been introduced as the new default runtime-polymorphic
executor for all I/O objects. This type alias points to the <codeclass="computeroutput"><spanclass="identifier">execution</span><spanclass="special">::</span><spanclass="identifier">any_executor</span><spanclass="special"><></span></code>
template with a set of supportable properties specified for use with
I/O. This change may break existing code that directly uses the old
Added a new constructor overload to <codeclass="computeroutput"><spanclass="identifier">use_awaitable_t</span></code>'s
default executor adapter, to enable conversion between executor types.
</li>
<liclass="listitem">
Added support for using <codeclass="computeroutput"><spanclass="identifier">detached_t</span></code>
as a default completion token, by adding members <codeclass="computeroutput"><spanclass="identifier">as_default_on</span><spanclass="special">()</span></code> and <codeclass="computeroutput"><spanclass="identifier">as_default_on_t</span><spanclass="special"><></span></code>.
</li>
<liclass="listitem">
Added a move constructor to <codeclass="computeroutput"><spanclass="identifier">ssl</span><spanclass="special">::</span><spanclass="identifier">stream</span><spanclass="special"><></span></code>.
and function <codeclass="computeroutput"><spanclass="identifier">get_associated_executor</span><spanclass="special">()</span></code>. Compiling an application with <codeclass="computeroutput"><spanclass="identifier">ASIO_NO_DEPRECATED</span></code> will now trigger a
compile error if any handler implements the <codeclass="computeroutput"><spanclass="identifier">asio_handler_invoke</span></code>
hook.
</li>
<liclass="listitem">
Added compile-time detection of the deprecated <codeclass="computeroutput"><spanclass="identifier">asio_handler_allocate</span></code>
and <codeclass="computeroutput"><spanclass="identifier">asio_handle_deallocate</span></code>
hooks. These hooks were deprecated with the introduction of the Networking
and function <codeclass="computeroutput"><spanclass="identifier">get_associated_allocator</span><spanclass="special">()</span></code>. Compiling an application with <codeclass="computeroutput"><spanclass="identifier">ASIO_NO_DEPRECATED</span></code> will now trigger a
compile error if any handler implements the <codeclass="computeroutput"><spanclass="identifier">asio_handler_allocate</span></code>
or <codeclass="computeroutput"><spanclass="identifier">asio_handler_deallocate</span></code>
hooks.
</li>
<liclass="listitem">
Implemented a number of performance optimisations, including:
Specialising single-buffer operations to use <codeclass="computeroutput"><spanclass="identifier">recv</span></code>
rather than <codeclass="computeroutput"><spanclass="identifier">recvmsg</span></code>,
<codeclass="computeroutput"><spanclass="identifier">send</span></code> rather than
<codeclass="computeroutput"><spanclass="identifier">sendmsg</span></code>, <codeclass="computeroutput"><spanclass="identifier">read</span></code> rather than <codeclass="computeroutput"><spanclass="identifier">readv</span></code>, and <codeclass="computeroutput"><spanclass="identifier">write</span></code>
rather than <codeclass="computeroutput"><spanclass="identifier">writev</span></code>.
</li>
<liclass="listitem">
Lightening the reference counting overhead of the polymorphic wrapper
Returning from system call operation wrappers as early as possible,
and only accessing <codeclass="computeroutput"><spanclass="identifier">errno</span></code>
and error codes when on an error path.
</li>
<liclass="listitem">
Applying additional optimisations if a "native" I/O executor
(such as <codeclass="computeroutput"><spanclass="identifier">io_context</span><spanclass="special">::</span><spanclass="identifier">exeutor_type</span></code>)
is detected.
</li>
</ul></div>
</li>
<liclass="listitem">
<pclass="simpara">
Added source location support to handler tracking. The new <codeclass="computeroutput"><spanclass="identifier">ASIO_HANDLER_LOCATION</span><spanclass="special">((</span><spanclass="identifier">file_name</span><spanclass="special">,</span>
<br> If <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">source_location</span></code> or <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">source_location</span></code>
are available, the <codeclass="computeroutput"><spanclass="identifier">use_awaitable_t</span></code>
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 <codeclass="computeroutput"><spanclass="identifier">use_awaitable_t</span></code>
object may also be explicitly constructed with location information.
</p>
</li>
<liclass="listitem">
Implemented various improvements to the <codeclass="literal">handlerviz.pl</code>
Marked the POSIX descriptor classes' move constructors as <codeclass="computeroutput"><spanclass="keyword">noexcept</span></code>.
</li>
<liclass="listitem">
Added the <codeclass="computeroutput"><spanclass="identifier">ssl</span><spanclass="special">::</span><spanclass="identifier">host_name_verification</span></code> class, which is
a drop-in replacement for <codeclass="computeroutput"><spanclass="identifier">ssl</span><spanclass="special">::</span><spanclass="identifier">rfc2818_verification</span></code>.
The <codeclass="computeroutput"><spanclass="identifier">ssl</span><spanclass="special">::</span><spanclass="identifier">rfc2818_verification</span></code> class has been marked
as deprecated. As a consequence of this change, SSL support now depends
on functions that were introduced in OpenSSL 1.0.2.
</li>
<liclass="listitem">
Added an <codeclass="computeroutput"><spanclass="identifier">ssl</span><spanclass="special">::</span><spanclass="identifier">context</span></code> constructor to take ownership
of a native handle.
</li>
<liclass="listitem">
Changed C++ language version detection with <codeclass="literal">gcc</code> to use
Fixed a work counting issue in the asynchronous resolve operation for endpoints.
</li>
<liclass="listitem">
Fixed the <codeclass="computeroutput"><spanclass="identifier">strand</span><spanclass="special"><></span></code>
converting constructors and assignment operators.
</li>
<liclass="listitem">
Ensured that resolvers are restarted correctly after a fork.
</li>
<liclass="listitem">
Fixed compatibility with the current NetBSD release.
</li>
<liclass="listitem">
Removed spurious handler requirement checks in some <codeclass="computeroutput"><spanclass="identifier">async_read</span></code>
overloads.
</li>
<liclass="listitem">
Changed the <codeclass="computeroutput"><spanclass="identifier">ssl</span><spanclass="special">::</span><spanclass="identifier">context</span></code> class to propagate non-EOF errors
from the <codeclass="computeroutput"><spanclass="identifier">add_certificate_authority</span></code>
function.
</li>
<liclass="listitem">
Fixed a Windows-specific <codeclass="computeroutput"><spanclass="identifier">thread_pool</span></code>
destructor hang that occurred when the pool had an associated I/O object.
</li>
<liclass="listitem">
Changed the <codeclass="literal">select</code> reactor to recreate the "self
pipe trick" sockets on error. This addresses an issue on some versions
of Windows, where these sockets are discconected after a system sleep.
</li>
<liclass="listitem">
Fixed a compile error in the buffered streams due to the lack of reference
collapsing in C++98.
</li>
<liclass="listitem">
Changed the <codeclass="computeroutput"><spanclass="identifier">priority_scheduler</span></code>
example to demonstrate calls to <codeclass="computeroutput"><spanclass="identifier">shutdown</span><spanclass="special">()</span></code> and <codeclass="computeroutput"><spanclass="identifier">destroy</span><spanclass="special">()</span></code>.
</li>
<liclass="listitem">
Removed some unnecessary null pointer checks.
</li>
<liclass="listitem">
Changed Windows platform detection to recognise TV titles as Windows apps.
</li>
<liclass="listitem">
Added some emscripten compatibility patches.
</li>
<liclass="listitem">
Fixed a compile error in the <codeclass="computeroutput"><spanclass="identifier">use_awaitable_t</span><spanclass="special">::</span><spanclass="identifier">as_default_on</span></code>
function.
</li>
<liclass="listitem">
Changed all uses of the boost.bind placeholders to use the <codeclass="computeroutput"><spanclass="identifier">boost</span><spanclass="special">::</span><spanclass="identifier">placeholders</span></code> namespace.
</li>
<liclass="listitem">
Fixed a potential compile error in the <codeclass="computeroutput"><spanclass="identifier">async_compose</span></code>
implementation due to incorrect overload selection.
<codeclass="computeroutput"><spanclass="identifier">completion_signature</span><spanclass="special"><</span><spanclass="identifier">T</span><spanclass="special">></span></code>: Checks if <codeclass="computeroutput"><spanclass="identifier">T</span></code>
is a signature of the form <codeclass="computeroutput"><spanclass="identifier">R</span><spanclass="special">(</span><spanclass="identifier">Args</span><spanclass="special">...)</span></code>.
</li>
<liclass="listitem">
<codeclass="computeroutput"><spanclass="identifier">completion_handler_for</span><spanclass="special"><</span><spanclass="identifier">T</span><spanclass="special">,</span><spanclass="identifier">Signature</span><spanclass="special">></span></code>: Checks if <codeclass="computeroutput"><spanclass="identifier">T</span></code>
is usable as a completion handler with the specified signature.
</li>
<liclass="listitem">
<codeclass="computeroutput"><spanclass="identifier">completion_token_for</span><spanclass="special"><</span><spanclass="identifier">T</span><spanclass="special">,</span><spanclass="identifier">Signature</span><spanclass="special">></span></code>: Checks if <codeclass="computeroutput"><spanclass="identifier">T</span></code>
is a completion token that can be used with async_initiate and the
specified signature.
</li>
<liclass="listitem">
For backward compatibility with pre-concepts C++, the macros <codeclass="computeroutput"><spanclass="special">(</span><spanclass="identifier">BOOST_</span><spanclass="special">)</span><spanclass="identifier">ASIO_COMPLETION_SIGNATURE</span></code>,
and <codeclass="computeroutput"><spanclass="special">(</span><spanclass="identifier">BOOST_</span><spanclass="special">)</span><spanclass="identifier">ASIO_COMPLETION_TOKEN_FOR</span></code>
are provided. These macros expand to <codeclass="computeroutput"><spanclass="keyword">typename</span></code>
when concepts are unsupported.
</li>
</ul></div>
</li>
<liclass="listitem">
<pclass="simpara">
Added the nested template type <codeclass="computeroutput"><spanclass="identifier">rebind_executor</span></code>
to all I/O object types, as a way to generically rebind them to use alternative
Changed the asynchronous operations' initiation function objects to report
their associated I/O executor via the nested type <codeclass="computeroutput"><spanclass="identifier">executor_type</span></code>
and member function <codeclass="computeroutput"><spanclass="identifier">get_executor</span><spanclass="special">()</span></code>. Note that the presence of <codeclass="computeroutput"><spanclass="identifier">executor_type</span></code> and <codeclass="computeroutput"><spanclass="identifier">get_executor</span><spanclass="special">()</span></code> should be treated as optional, and consequently
it may be preferable to access them via the <codeclass="computeroutput"><spanclass="identifier">associated_executor</span></code>
trait and the <codeclass="computeroutput"><spanclass="identifier">get_associated_executor</span><spanclass="special">()</span></code> helper function.
</li>
<liclass="listitem">
<pclass="simpara">
Added the <codeclass="computeroutput"><spanclass="identifier">default_completion_token</span></code>
trait, so that every I/O executor type now has an associated default completion
token type. This trait may be used in asynchronous operation declarations
<spanclass="identifier">co_await</span><spanclass="identifier">socket</span><spanclass="special">.</span><spanclass="identifier">async_connect</span><spanclass="special">(</span><spanclass="identifier">my_endpoint</span><spanclass="special">);</span><spanclass="comment">// Defaults to use_awaitable.</span>
</pre>
<pclass="simpara">
<br> In this example, the type of the <codeclass="computeroutput"><spanclass="identifier">socket</span></code>
object is transformed from <codeclass="computeroutput"><spanclass="identifier">tcp</span><spanclass="special">::</span><spanclass="identifier">socket</span></code>
to have an I/O executor with the default completion token set to <codeclass="computeroutput"><spanclass="identifier">use_awaitable</span></code>. Alternatively, the socket
<spanclass="identifier">co_await</span><spanclass="identifier">socket</span><spanclass="special">.</span><spanclass="identifier">async_connect</span><spanclass="special">(</span><spanclass="identifier">my_endpoint</span><spanclass="special">);</span><spanclass="comment">// Defaults to use_awaitable.</span>
Improved performance slightly by eliminating a redundant move construction
when completed handlers are dispatched.
</li>
<liclass="listitem">
Eliminated a compiler warning by annotating a <codeclass="computeroutput"><spanclass="keyword">case</span></code>
fall-through in the free function <codeclass="computeroutput"><spanclass="identifier">connect</span><spanclass="special">()</span></code> implementation.
</li>
<liclass="listitem">
Fixed the <codeclass="computeroutput"><spanclass="identifier">is_</span><spanclass="special">*</span><spanclass="identifier">_buffer_sequence</span></code> detection traits for
user-defined sequence types.
</li>
<liclass="listitem">
Fixed some Windows-specific warnings about an incompatible pointer cast
when obtaining the <codeclass="computeroutput"><spanclass="identifier">CancelIoEx</span></code>
entry point.
</li>
<liclass="listitem">
Changed to automatically set the defaults when opening a serial port on
Windows.
</li>
<liclass="listitem">
Changed the serial port <codeclass="computeroutput"><spanclass="identifier">get_option</span><spanclass="special">()</span></code> member function to be const.
</li>
<liclass="listitem">
Fixed a name hiding issue with the WinRT stream-oriented socket backend's
All I/O objects now have an additional <codeclass="computeroutput"><spanclass="identifier">Executor</span></code>
template parameter. This template parameter defaults to the <codeclass="computeroutput"><spanclass="identifier">asio</span><spanclass="special">::</span><spanclass="identifier">executor</span></code> type (the polymorphic
executor wrapper) but can be used to specify a user-defined executor
type.
</li>
<liclass="listitem">
I/O objects' constructors and functions that previously took an
now accept either an <codeclass="computeroutput"><spanclass="identifier">Executor</span></code>
or a reference to a concrete <codeclass="computeroutput"><spanclass="identifier">ExecutionContext</span></code>
(such as <codeclass="computeroutput"><spanclass="identifier">asio</span><spanclass="special">::</span><spanclass="identifier">io_context</span></code> or <codeclass="computeroutput"><spanclass="identifier">asio</span><spanclass="special">::</span><spanclass="identifier">thread_pool</span></code>).
</li>
<liclass="listitem">
<pclass="simpara">
Note: One potential source of breakage in existing user code is when
reusing an I/O object's <codeclass="computeroutput"><spanclass="identifier">io_context</span></code>
cause the invocation of the function object <codeclass="computeroutput"><spanclass="identifier">initiation</span></code>
as if by calling <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">forward</span><spanclass="special"><</span><spanclass="identifier">Initiation</span><spanclass="special">>(</span><spanclass="identifier">initiation</span><spanclass="special">)(</span><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">move</span><spanclass="special">(</span><spanclass="identifier">handler</span><spanclass="special">),</span><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">forward</span><spanclass="special"><</span><spanclass="identifier">Args</span><spanclass="special">>(</span><spanclass="identifier">args</span><spanclass="special">)...)</span></code>. Note that the invocation of
<codeclass="computeroutput"><spanclass="identifier">initiation</span></code> may be
deferred (e.g. lazily evaluated), in which case <codeclass="computeroutput"><spanclass="identifier">initiation</span></code>
and <codeclass="computeroutput"><spanclass="identifier">args</span></code> must be
decay-copied and moved as required.
</li>
<liclass="listitem">
A helper function template <codeclass="computeroutput"><spanclass="identifier">async_initiate</span></code>
has also been added as a wrapper for the invocation of <codeclass="computeroutput"><spanclass="identifier">async_result</span><spanclass="special"><>::</span><spanclass="identifier">initiate</span></code>. For backward compatibility,
this function supports both the old and new <codeclass="computeroutput"><spanclass="identifier">async_result</span></code>
forms.
</li>
<liclass="listitem">
The composed operations examples have been updated to use <codeclass="computeroutput"><spanclass="identifier">async_initiate</span></code>.
</li>
<liclass="listitem">
The previously deprecated <codeclass="computeroutput"><spanclass="identifier">handler_type</span></code>
trait and single-argument form of <codeclass="computeroutput"><spanclass="identifier">async_result</span></code>
have now been removed.
</li>
</ul></div>
</li>
<liclass="listitem">
Updated the Coroutines TS support and promoted it to the <codeclass="computeroutput"><spanclass="identifier">asio</span></code> namespace.
and <codeclass="computeroutput"><spanclass="identifier">redirect_error</span></code>
facilities have been moved from the <codeclass="computeroutput"><spanclass="identifier">asio</span><spanclass="special">::</span><spanclass="identifier">experimental</span></code>
namespace to namespace <codeclass="computeroutput"><spanclass="identifier">asio</span></code>.
As part of this change, the <codeclass="computeroutput"><spanclass="identifier">this_coro</span><spanclass="special">::</span><spanclass="identifier">token</span><spanclass="special">()</span></code> awaitable has been superseded by
the <codeclass="computeroutput"><spanclass="identifier">asio</span><spanclass="special">::</span><spanclass="identifier">use_awaitable</span></code> completion token.
</li>
<liclass="listitem">
Please note that the <codeclass="computeroutput"><spanclass="identifier">use_awaitable</span></code>
and <codeclass="computeroutput"><spanclass="identifier">redirect_error</span></code>
completion tokens work only with asynchronous operations that use
the new form of <codeclass="computeroutput"><spanclass="identifier">async_result</span></code>
with member function <codeclass="computeroutput"><spanclass="identifier">initiate</span></code>.
Furthermore, when using <codeclass="computeroutput"><spanclass="identifier">use_awaitable</span></code>,
please be aware that the asynchronous operation is not initiated
until <codeclass="computeroutput"><spanclass="identifier">co_await</span></code> is
applied to the <codeclass="computeroutput"><spanclass="identifier">awaitable</span><spanclass="special"><></span></code>.
</li>
</ul></div>
</li>
<liclass="listitem">
Added a new <codeclass="computeroutput"><spanclass="identifier">DynamicBuffer_v2</span></code>
is explicitly defined, in which case it delegates to <codeclass="computeroutput"><spanclass="identifier">is_dynamic_buffer_v2</span></code>).
</li>
<liclass="listitem">
For convenience, the <codeclass="computeroutput"><spanclass="identifier">dynamic_string_buffer</span></code>
and <codeclass="computeroutput"><spanclass="identifier">dynamic_vector_buffer</span></code>
classes conform to both <codeclass="computeroutput"><spanclass="identifier">DynamicBuffer_v1</span></code>
and <codeclass="computeroutput"><spanclass="identifier">DynamicBuffer_v2</span></code>
requirements.
</li>
<liclass="listitem">
When <codeclass="computeroutput"><spanclass="identifier">ASIO_NO_DYNAMIC_BUFFER_V1</span></code>
is defined, all support for <codeclass="computeroutput"><spanclass="identifier">DynamicBuffer_v1</span></code>
types and functions is #ifdef-ed out. Support for using <codeclass="computeroutput"><spanclass="identifier">basic_streambuf</span></code> with the <codeclass="computeroutput"><spanclass="identifier">read</span></code>, <codeclass="computeroutput"><spanclass="identifier">async_read</span></code>,
<codeclass="computeroutput"><spanclass="identifier">read_until</span></code>, <codeclass="computeroutput"><spanclass="identifier">async_read_until</span></code>, <codeclass="computeroutput"><spanclass="identifier">write</span></code>, and <codeclass="computeroutput"><spanclass="identifier">async_write</span></code>
functions is also disabled as a consequence.
</li>
<liclass="listitem">
Note: This change should have no impact on existing source code that
simply uses dynamic buffers in conjunction with Asio's composed operations.
</li>
</ul></div>
</li>
<liclass="listitem">
Added a new <codeclass="computeroutput"><spanclass="identifier">async_compose</span></code>
function that simplifies the implementation of user-defined asynchronous
operations.
</li>
<liclass="listitem">
Added a <codeclass="computeroutput"><spanclass="identifier">make_strand</span></code> function,
which creates a <codeclass="computeroutput"><spanclass="identifier">strand</span></code>
with a deduced <codeclass="computeroutput"><spanclass="identifier">Executor</span></code>
template argument.
</li>
<liclass="listitem">
Relaxed the completion condition type requirements to only require move-constructibility
rather than copy-constructibility.
</li>
<liclass="listitem">
Added a constructor for <codeclass="computeroutput"><spanclass="identifier">local</span><spanclass="special">::</span><spanclass="identifier">basic_endpoint</span></code>
that takes a <codeclass="computeroutput"><spanclass="identifier">string_view</span></code>.
</li>
<liclass="listitem">
Added the noexcept qualifier to various member functions of the <codeclass="computeroutput"><spanclass="identifier">ip</span><spanclass="special">::</span><spanclass="identifier">address</span></code>, <codeclass="computeroutput"><spanclass="identifier">ip</span><spanclass="special">::</span><spanclass="identifier">address_v4</span></code>,
Users should define <codeclass="computeroutput"><spanclass="identifier">ASIO_ENABLE_BOOST</span></code>
to explicitly disable standalone mode when compiling with C++11 or
later.
</li>
<liclass="listitem">
The <codeclass="computeroutput"><spanclass="identifier">configure</span></code> script
now defaults to a standalone build unless Boost is specified or detected.
</li>
</ul></div>
</li>
<liclass="listitem">
Enabled recycling of the memory used to type-erase a function object with
the polymorphic executor.
</li>
<liclass="listitem">
Changed receive operations to return the correct number of bytes transferred
when truncation (<codeclass="computeroutput"><spanclass="identifier">error</span><spanclass="special">::</span><spanclass="identifier">message_size</span></code>)
occurs on a datagram-oriented socket.
</li>
<liclass="listitem">
Fixed multicast behaviour on QNX by automatically applying <codeclass="computeroutput"><spanclass="identifier">SO_REUSEPORT</span></code> when the <codeclass="computeroutput"><spanclass="identifier">reuse_address</span></code>
option is set.
</li>
<liclass="listitem">
Added inclusion of <codeclass="computeroutput"><spanclass="identifier">unistd</span><spanclass="special">.</span><spanclass="identifier">h</span></code> when
targeting Haiku OS, to fix feature detection.
</li>
<liclass="listitem">
Added the <codeclass="computeroutput"><spanclass="identifier">network_v</span><spanclass="special">[</span><spanclass="number">46</span><spanclass="special">].</span><spanclass="identifier">hpp</span></code>
headers to the top-level convenience header.
</li>
<liclass="listitem">
Fixed calculation of absolute timeout when the backend uses <codeclass="computeroutput"><spanclass="identifier">pthread_cond_timedwait</span></code>.
</li>
<liclass="listitem">
Changed the range-based asynchronous connect operation to deduce the <codeclass="computeroutput"><spanclass="identifier">EndpointSequence</span></code> iterator type rather
than assume the presence of a <codeclass="computeroutput"><spanclass="identifier">const_iterator</span></code>
and <codeclass="computeroutput"><spanclass="identifier">buffer_sequence_end</span></code>
to prevent implicit conversion. This change addresses an issue where a
call to <codeclass="computeroutput"><spanclass="identifier">buffer_sequence_begin</span></code>
or <codeclass="computeroutput"><spanclass="identifier">buffer_sequence_end</span></code>
could trigger an implicit conversion to <codeclass="computeroutput"><spanclass="identifier">const_buffer</span></code>
or <codeclass="computeroutput"><spanclass="identifier">mutable_buffer</span></code>. Whenever
this implicit conversion occurred, the return value of <codeclass="computeroutput"><spanclass="identifier">buffer_sequence_begin</span></code>
or <codeclass="computeroutput"><spanclass="identifier">buffer_sequence_end</span></code>
would point to a temporary object.
</li>
<liclass="listitem">
Ensured SSL handshake errors are propagated to the peer before the local
operation completes.
</li>
<liclass="listitem">
Suppressed the <codeclass="computeroutput"><spanclass="identifier">eof</span></code> error
on SSL shutdown as it actually indicates success.
</li>
<liclass="listitem">
Added a fallback error code for when we OpenSSL produces an <codeclass="computeroutput"><spanclass="identifier">SSL_ERROR_SYSCALL</span></code> result without an associated
error.
</li>
<liclass="listitem">
Changed composed asynchronous read and write operations to move, rather
than copy, the buffer sequence objects when the composed operation implementation
is moved.
</li>
<liclass="listitem">
Changed to use <codeclass="computeroutput"><spanclass="special"><</span><spanclass="identifier">atomic</span><spanclass="special">></span></code> when targeting apple/clang/libc++ with
recent Xcode versions, even for C++03. This fixes a warning about the deprecation
of <codeclass="computeroutput"><spanclass="identifier">OSMemoryBarrier</span></code>.
</li>
<liclass="listitem">
Fixed compile errors that occur when using the composed read and write
operations with MSVC 11.0, by disabling <codeclass="computeroutput"><spanclass="keyword">decltype</span></code>
support for that compiler.
</li>
<liclass="listitem">
Increased the default value of <codeclass="computeroutput"><spanclass="identifier">_WIN32_WINNT</span></code>
to <codeclass="computeroutput"><spanclass="number">0x0601</span></code> (Windows 7).
to note that it may call the supplied function object in the current thread.
</li>
<liclass="listitem">
Updated <codeclass="computeroutput"><spanclass="identifier">post</span></code> and <codeclass="computeroutput"><spanclass="identifier">defer</span></code> documentation to clarify the the
Fixed a problem with the detection of <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">future</span></code>
availability with libstdc++.
</li>
<liclass="listitem">
Fixed compile error in regex overload of <codeclass="computeroutput"><spanclass="identifier">read_until</span></code>.
</li>
<liclass="listitem">
Fixed a timer heap corruption issue that can occur when moving a cancelled
timer.
</li>
<liclass="listitem">
Fixed detection of <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">string_view</span></code>
and <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">string_view</span></code> with newer clang/libc++.
</li>
<liclass="listitem">
Fixed MSVC version detection for availability of <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">invoke_result</span></code>.
</li>
<liclass="listitem">
Fixed the buffer sequence traits to test the new requirements, if <codeclass="computeroutput"><spanclass="keyword">decltype</span></code> is available.
</li>
<liclass="listitem">
Fixed an MSVC issue when building with exceptions disabled.
</li>
<liclass="listitem">
Added SSL context options for TLS v1.3.
</li>
<liclass="listitem">
Added a compile-time test for TLS v1 support.
</li>
<liclass="listitem">
Fixed the macro used to test for TLS v1.2 support.
</li>
<liclass="listitem">
Prevented global objects from being created once per thread on Windows.
</li>
<liclass="listitem">
Fixed a crash when using <codeclass="computeroutput"><spanclass="identifier">size</span><spanclass="special">()</span></code>, <codeclass="computeroutput"><spanclass="identifier">max_size</span><spanclass="special">()</span></code> or <codeclass="computeroutput"><spanclass="identifier">empty</span><spanclass="special">()</span></code> on default-constructed resolver results.
</li>
<liclass="listitem">
Changed to move the return value in basic_resolver_results::begin() to
avoid copying.
</li>
<liclass="listitem">
Enabled move support for the Intel Compiler.
</li>
<liclass="listitem">
Fixed <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">string_view</span></code> detection issue when using
clang-cl.
</li>
<liclass="listitem">
Fixed the handler tracking operation name for <codeclass="computeroutput"><spanclass="identifier">io_context</span><spanclass="special">::</span><spanclass="identifier">executor_type</span><spanclass="special">::</span><spanclass="identifier">dispatch</span></code>.
</li>
<liclass="listitem">
Fixed a buffer overflow that could occur when parsing an address string
with a 64-bit scope id.
</li>
<liclass="listitem">
Added examples showing how to write composed operations.
</li>
<liclass="listitem">
Added C++11 versions of the Timeouts, Timers, SOCKS4 and SSL examples.
Used <codeclass="computeroutput"><spanclass="identifier">asio</span><spanclass="special">::</span><spanclass="identifier">steady_timer</span></code> rather than <codeclass="computeroutput"><spanclass="identifier">asio</span><spanclass="special">::</span><spanclass="identifier">deadline_timer</span></code>.
</li>
<liclass="listitem">
Used <codeclass="computeroutput"><spanclass="identifier">asio</span><spanclass="special">::</span><spanclass="identifier">dynamic_buffer</span></code> rather than <codeclass="computeroutput"><spanclass="identifier">asio</span><spanclass="special">::</span><spanclass="identifier">streambuf</span></code>.
</li>
<liclass="listitem">
Used timed <codeclass="computeroutput"><spanclass="identifier">asio</span><spanclass="special">::</span><spanclass="identifier">io_context</span><spanclass="special">::</span><spanclass="identifier">run_for</span><spanclass="special">()</span></code>
function for blocking clients.
</li>
<liclass="listitem">
Added example showing a custom completion token for blocking with
timeouts.
</li>
</ul></div>
</li>
<liclass="listitem">
Fixed unit tests to compile when <codeclass="computeroutput"><spanclass="special">(</span><spanclass="identifier">BOOST_</span><spanclass="special">)</span><spanclass="identifier">ASIO_NO_DEPRECATED</span></code> is defined.
</li>
<liclass="listitem">
Changed socket iostreams to use chrono by default, to fix compatibility
with the Networking TS. Define <codeclass="computeroutput"><spanclass="special">(</span><spanclass="identifier">BOOST_</span><spanclass="special">)</span><spanclass="identifier">ASIO_USE_BOOST_DATE_TIME_FOR_SOCKET_IOSTREAM</span></code>
to enable the old Boost.Date_Time interface in <codeclass="computeroutput"><spanclass="identifier">basic_socket_streambuf</span></code>
and <codeclass="computeroutput"><spanclass="identifier">basic_socket_iostream</span></code>.
</li>
<liclass="listitem">
Updated examples to use chrono rather than Boost.Date_Time.
</li>
<liclass="listitem">
Fixed an incorrect member function detector in the <codeclass="computeroutput"><spanclass="identifier">is_dynamic_buffer</span></code>
trait.
</li>
<liclass="listitem">
Fixed an <codeclass="computeroutput"><spanclass="identifier">async_result</span></code> incompatibility
with deprecated <codeclass="computeroutput"><spanclass="identifier">handler_type</span></code>.
</li>
<liclass="listitem">
Added a missing move optimisation in the SSL stream implementation.
Eliminated deprecation warning with MSVC by using <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">invoke_result</span></code>
rather than <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">result_of</span></code>.
</li>
<liclass="listitem">
Changed to use <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">string_view</span></code> for C++17 or later, and
<codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">experimental</span><spanclass="special">::</span><spanclass="identifier">string_view</span></code> for C++14. Define the preprocessor
to work with completion signatures containing reference parameters.
</li>
<liclass="listitem">
Ensured that stackful coroutines launched using <codeclass="computeroutput"><spanclass="identifier">spawn</span><spanclass="special">()</span></code> correctly store decayed copies of their
Completed the interface changes to reflect the Networking TS (<ahref="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2017/n4656.pdf"target="_top">N4656</a>).
See the <aclass="link"href="net_ts.html"title="Networking TS compatibility">list</a> of new interfaces
and, where applicable, the corresponding old interfaces that have
been superseded.
</li>
<liclass="listitem">
The service template parameters, and the corresponding classes, are
disabled by default. For example, instead of <codeclass="computeroutput"><spanclass="identifier">basic_socket</span><spanclass="special"><</span><spanclass="identifier">Protocol</span><spanclass="special">,</span><spanclass="identifier">SocketService</span><spanclass="special">></span></code> we now have simply <codeclass="computeroutput"><spanclass="identifier">basic_socket</span><spanclass="special"><</span><spanclass="identifier">Protocol</span><spanclass="special">></span></code>.
The old interface can be enabled by defining the <codeclass="computeroutput"><spanclass="special">(</span><spanclass="identifier">BOOST_</span><spanclass="special">)</span><spanclass="identifier">ASIO_ENABLE_OLD_SERVICES</span></code> macro.
</li>
</ul></div>
</li>
<liclass="listitem">
Added support for customised handler tracking.
</li>
<liclass="listitem">
Added reactor-related (i.e. descriptor readiness) events to handler tracking.
</li>
<liclass="listitem">
Added special <aclass="link"href="overview/core/concurrency_hint.html"title="Concurrency Hints">concurrency
hint</a> values that may be used to disable locking on a per <codeclass="computeroutput"><spanclass="identifier">io_context</span></code> basis.
</li>
<liclass="listitem">
Enabled perfect forwarding for the first <codeclass="computeroutput"><spanclass="identifier">ssl</span><spanclass="special">::</span><spanclass="identifier">stream</span><spanclass="special"><></span></code> constructor argument.
</li>
<liclass="listitem">
Added ability to release ownership of the underlying native socket. (Requires
Windows 8.1 or later when using the I/O completion port backend.)
New <codeclass="computeroutput"><spanclass="identifier">Executor</span></code> type
requirements and classes to support an executor framework, including
the <codeclass="computeroutput"><spanclass="identifier">execution_context</span></code>
base class, the <codeclass="computeroutput"><spanclass="identifier">executor_work</span></code>
class for tracking outstanding work, and the <codeclass="computeroutput"><spanclass="identifier">executor</span></code>
polymorphic wrapper. Free functions <codeclass="computeroutput"><spanclass="identifier">dispatch</span><spanclass="special">()</span></code>, <codeclass="computeroutput"><spanclass="identifier">post</span><spanclass="special">()</span></code> and <codeclass="computeroutput"><spanclass="identifier">defer</span><spanclass="special">()</span></code> have been added and are used to
submit function objects to executors.
</li>
<liclass="listitem">
Completion handlers now have an associated executor and associated
allocator. The free function <codeclass="computeroutput"><spanclass="identifier">wrap</span><spanclass="special">()</span></code> is used to associate an executor
with a handler or other object. The handler hooks for allocation,
invocation and continuation have been deprecated.
</li>
<liclass="listitem">
A <codeclass="computeroutput"><spanclass="identifier">system_executor</span></code>
class has been added as a default executor.
</li>
<liclass="listitem">
The <codeclass="computeroutput"><spanclass="identifier">io_service</span></code> class
is now derived from <codeclass="computeroutput"><spanclass="identifier">execution_context</span></code>
and implements the executor type requirements in its nested <codeclass="computeroutput"><spanclass="identifier">executor_type</span></code> class. The member
functions <codeclass="computeroutput"><spanclass="identifier">dispatch</span><spanclass="special">()</span></code>, <codeclass="computeroutput"><spanclass="identifier">post</span><spanclass="special">()</span></code>, <codeclass="computeroutput"><spanclass="identifier">defer</span><spanclass="special">()</span></code> and <codeclass="computeroutput"><spanclass="identifier">wrap</span><spanclass="special">()</span></code> have been deprecated. The <codeclass="computeroutput"><spanclass="identifier">io_service</span><spanclass="special">::</span><spanclass="identifier">work</span></code> class has been deprecated.
</li>
<liclass="listitem">
The <codeclass="computeroutput"><spanclass="identifier">io_service</span></code> member
function <codeclass="computeroutput"><spanclass="identifier">reset</span><spanclass="special">()</span></code>
has been renamed to <codeclass="computeroutput"><spanclass="identifier">restart</span><spanclass="special">()</span></code>. The old name is retained for backward
compatibility but has been deprecated.
</li>
<liclass="listitem">
The <codeclass="computeroutput"><spanclass="identifier">make_service</span><spanclass="special"><>()</span></code> function is now used to
add a new service to an execution context such as an <codeclass="computeroutput"><spanclass="identifier">io_service</span></code>. The <codeclass="computeroutput"><spanclass="identifier">add_service</span><spanclass="special">()</span></code> function has been deprecated.
</li>
<liclass="listitem">
A new <codeclass="computeroutput"><spanclass="identifier">strand</span><spanclass="special"><></span></code>
template has been added to allow strand functionality to be used
with generic executor types.
</li>
<liclass="listitem">
I/O objects (such as sockets and timers) now provide access to their
via a <codeclass="computeroutput"><spanclass="identifier">context</span><spanclass="special">()</span></code>
member function. The <codeclass="computeroutput"><spanclass="identifier">get_io_service</span><spanclass="special">()</span></code> member function is deprecated.
</li>
<liclass="listitem">
All asynchronous operations and executor operations now support move-only
handlers. However, the deprecated <codeclass="computeroutput"><spanclass="identifier">io_service</span><spanclass="special">::</span><spanclass="identifier">post</span><spanclass="special">()</span></code>, <codeclass="computeroutput"><spanclass="identifier">io_service</span><spanclass="special">::</span><spanclass="identifier">dispatch</span><spanclass="special">()</span></code>, <codeclass="computeroutput"><spanclass="identifier">io_service</span><spanclass="special">::</span><spanclass="identifier">strand</span><spanclass="special">::</span><spanclass="identifier">post</span><spanclass="special">()</span></code> and <codeclass="computeroutput"><spanclass="identifier">io_service</span><spanclass="special">::</span><spanclass="identifier">strand</span><spanclass="special">::</span><spanclass="identifier">dispatch</span><spanclass="special">()</span></code> functions still require copyable
handlers.
</li>
<liclass="listitem">
Waitable timer objects are now movable.
</li>
<liclass="listitem">
Waitable timers, socket iostreams and socket streambufs now provide
an <codeclass="computeroutput"><spanclass="identifier">expiry</span><spanclass="special">()</span></code>
member function for obtaining the expiry time. The accessors <codeclass="computeroutput"><spanclass="identifier">expires_at</span><spanclass="special">()</span></code>
and <codeclass="computeroutput"><spanclass="identifier">expires_after</span><spanclass="special">()</span></code> have been deprecated, though those
names are retained for the mutating members.
</li>
<liclass="listitem">
The <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">packaged_task</span></code> class template is
now supported as a completion handler. The initiating operation automatically
returns the future associated with the task. The <codeclass="computeroutput"><spanclass="identifier">package</span><spanclass="special">()</span></code> function has been added as a convenient
factory for packaged tasks.
</li>
<liclass="listitem">
Sockets, socket acceptors and descriptors now provide <codeclass="computeroutput"><spanclass="identifier">wait</span><spanclass="special">()</span></code>
and <codeclass="computeroutput"><spanclass="identifier">async_wait</span><spanclass="special">()</span></code>
operations that may be used to wait for readiness. The <codeclass="computeroutput"><spanclass="identifier">null_buffers</span></code> type has been deprecated.
</li>
<liclass="listitem">
The proposed error code enum classes are simulated using namespaces.
Existing asio error codes now have a correspondence with the standard
error conditions.
</li>
<liclass="listitem">
Conversion between IP address types, and conversion from string to
address, is now supported via the <codeclass="computeroutput"><spanclass="identifier">address_cast</span><spanclass="special"><>()</span></code>, <codeclass="computeroutput"><spanclass="identifier">make_address</span><spanclass="special">()</span></code>, <codeclass="computeroutput"><spanclass="identifier">make_address_v4</span><spanclass="special">()</span></code> and <codeclass="computeroutput"><spanclass="identifier">make_address_v6</span><spanclass="special">()</span></code> free functions. The <codeclass="computeroutput"><spanclass="identifier">from_string</span><spanclass="special">()</span></code>,
and <codeclass="computeroutput"><spanclass="identifier">v4_mapped</span><spanclass="special">()</span></code>
member functions have been deprecated.
</li>
<liclass="listitem">
A default-constructed <codeclass="computeroutput"><spanclass="identifier">ip</span><spanclass="special">::</span><spanclass="identifier">address</span></code>
now represents an invalid address value that is neither IPv4 nor
IPv6.
</li>
<liclass="listitem">
New <codeclass="computeroutput"><spanclass="identifier">buffer</span><spanclass="special">()</span></code>
overloads that generate mutable buffers for non-const <codeclass="computeroutput"><spanclass="identifier">string</span></code> objects.
</li>
<liclass="listitem">
Support for dynamic buffer sequences that automatically grow and
shrink to accomodate data as it is read or written. This is a generic
facility similar to the existing <codeclass="computeroutput"><spanclass="identifier">asio</span><spanclass="special">::</span><spanclass="identifier">streambuf</span></code>
New <codeclass="computeroutput"><spanclass="identifier">dynamic_string_buffer</span></code>
and <codeclass="computeroutput"><spanclass="identifier">dynamic_vector_buffer</span></code>
adapter classes that meet the <codeclass="computeroutput"><spanclass="identifier">DynamicBufferSequence</span></code>
type requirements.
</li>
<liclass="listitem">
New <codeclass="computeroutput"><spanclass="identifier">dynamic_buffer</span><spanclass="special">()</span></code> factory functions for creating
a dynamic buffer adapter for a <codeclass="computeroutput"><spanclass="identifier">vector</span></code>
or <codeclass="computeroutput"><spanclass="identifier">string</span></code>.
</li>
<liclass="listitem">
New overloads for the <codeclass="computeroutput"><spanclass="identifier">read</span><spanclass="special">()</span></code>, <codeclass="computeroutput"><spanclass="identifier">async_read</span><spanclass="special">()</span></code>, <codeclass="computeroutput"><spanclass="identifier">write</span><spanclass="special">()</span></code> and <codeclass="computeroutput"><spanclass="identifier">async_write</span><spanclass="special">()</span></code>, <codeclass="computeroutput"><spanclass="identifier">read_until</span><spanclass="special">()</span></code> and <codeclass="computeroutput"><spanclass="identifier">async_read_until</span><spanclass="special">()</span></code> free functions that directly
support dynamic buffer sequences.
</li>
</ul></div>
</li>
<liclass="listitem">
Support for networks and address ranges. Thanks go to Oliver Kowalke
for contributing to the design and providing the implementation on
which this facility is based. The following new classes have been
and <codeclass="computeroutput"><spanclass="identifier">yield_context</span></code> to permit
nested calls to the completion handler.
</li>
<liclass="listitem">
Removed previously deprecated functions.
</li>
<liclass="listitem">
Added options for disabling TLS v1.1 and v1.2.
</li>
<liclass="listitem">
Changed the SSL wrapper to call the password callback when loading an in-memory
key.
</li>
<liclass="listitem">
Changed the tutorial to use <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">endl</span></code>
to ensure output is flushed.
</li>
<liclass="listitem">
Fixed false SSL error reports by ensuring that the SSL error queue is cleared
prior to each operation.
</li>
<liclass="listitem">
Fixed an <codeclass="computeroutput"><spanclass="identifier">ssl</span><spanclass="special">::</span><spanclass="identifier">stream</span><spanclass="special"><></span></code>
bug that may result in spurious 'short read' errors.
</li>
<liclass="listitem">
Enabled perfect forwarding for the first <codeclass="computeroutput"><spanclass="identifier">ssl</span><spanclass="special">::</span><spanclass="identifier">stream</span><spanclass="special"><></span></code> constructor argument.
</li>
<liclass="listitem">
Added standalone Asio support for Clang when used with libstdc++ and C++11.
</li>
<liclass="listitem">
Fixed an unsigned integer overflow reported by Clang's integer sanitizer.
</li>
<liclass="listitem">
Added support for move-only return types when using a <codeclass="computeroutput"><spanclass="identifier">yield_context</span></code>
object with asynchronous operations.
</li>
<liclass="listitem">
Ensured errors generated by Windows' <codeclass="computeroutput"><spanclass="identifier">ConnectEx</span></code>
function are mapped to their portable equivalents.
</li>
<liclass="listitem">
Changed multicast test to treat certain <codeclass="computeroutput"><spanclass="identifier">join_group</span></code>
Fixed the <codeclass="literal">kqueue</code> reactor so that it works on FreeBSD.
</li>
<liclass="listitem">
Fixed an issue in the <codeclass="literal">kqueue</code> reactor which resulted
in spinning when using serial ports on Mac OS.
</li>
<liclass="listitem">
Fixed <codeclass="literal">kqueue</code> reactor support for read-only file descriptors.
</li>
<liclass="listitem">
Fixed a compile error when using the <codeclass="literal">/dev/poll</code> reactor.
</li>
<liclass="listitem">
Changed the Windows backend to use <codeclass="computeroutput"><spanclass="identifier">WSASocketW</span></code>,
as <codeclass="computeroutput"><spanclass="identifier">WSASocketA</span></code> has been
deprecated.
</li>
<liclass="listitem">
Fixed some warnings reported by Visual C++ 2013.
</li>
<liclass="listitem">
Fixed integer type used in the WinRT version of the byte-order conversion
functions.
</li>
<liclass="listitem">
Changed documentation to indicate that <codeclass="computeroutput"><spanclass="identifier">use_future</span></code>
and <codeclass="computeroutput"><spanclass="identifier">spawn</span><spanclass="special">()</span></code>
are not made available when including the <codeclass="computeroutput"><spanclass="identifier">asio</span><spanclass="special">.</span><spanclass="identifier">hpp</span></code>
as deprecated. Use <codeclass="computeroutput"><spanclass="identifier">asio</span><spanclass="special">::</span><spanclass="identifier">io_service</span><spanclass="special">::</span><spanclass="identifier">strand</span></code>
Worked around a <codeclass="literal">gcc</code> problem to do with anonymous enums.
</li>
<liclass="listitem">
Reverted the Windows <codeclass="computeroutput"><spanclass="identifier">HANDLE</span></code>
backend change to ignore <codeclass="computeroutput"><spanclass="identifier">ERROR_MORE_DATA</span></code>.
Instead, the error will be propagated as with any other (i.e. in an <codeclass="computeroutput"><spanclass="identifier">error_code</span></code> or thrown as a <codeclass="computeroutput"><spanclass="identifier">system_error</span></code>), and the number of bytes
transferred will be returned. For code that needs to handle partial messages,
the <codeclass="computeroutput"><spanclass="identifier">error_code</span></code> overload
should be used.
</li>
<liclass="listitem">
Fixed an off-by-one error in the <codeclass="computeroutput"><spanclass="identifier">signal_set</span></code>
implementation's signal number check.
</li>
<liclass="listitem">
Changed the Windows IOCP backend to not assume that <codeclass="computeroutput"><spanclass="identifier">SO_UPDATE_CONNECT_CONTEXT</span></code>
is defined.
</li>
<liclass="listitem">
Fixed a Windows-specific issue, introduced in Asio 1.10.2, by using <codeclass="computeroutput"><spanclass="identifier">VerifyVersionInfo</span></code> rather than <codeclass="computeroutput"><spanclass="identifier">GetVersionEx</span></code>, as <codeclass="computeroutput"><spanclass="identifier">GetVersionEx</span></code>
has been deprecated.
</li>
<liclass="listitem">
Changed to use SSE2 intrinsics rather than inline assembly, to allow the
to work correctly with new Boost.Coroutine interface.
</li>
<liclass="listitem">
Ensured that incomplete <codeclass="computeroutput"><spanclass="identifier">asio</span><spanclass="special">::</span><spanclass="identifier">spawn</span><spanclass="special">()</span></code> coroutines are correctly unwound when
cleaned up by the <codeclass="computeroutput"><spanclass="identifier">io_service</span></code>
destructor.
</li>
<liclass="listitem">
Fixed delegation of continuation hook for handlers produced by <codeclass="computeroutput"><spanclass="identifier">io_service</span><spanclass="special">::</span><spanclass="identifier">wrap</span><spanclass="special">()</span></code>
and <codeclass="computeroutput"><spanclass="identifier">strand</span><spanclass="special">::</span><spanclass="identifier">wrap</span><spanclass="special">()</span></code>.
</li>
<liclass="listitem">
Changed the Windows I/O completion port backend to use <codeclass="computeroutput"><spanclass="identifier">ConnectEx</span></code>,
if available, for connection-oriented IP sockets.
</li>
<liclass="listitem">
Changed the <codeclass="computeroutput"><spanclass="identifier">io_service</span></code>
backend for non-Windows (and non-IOCP Windows) platforms to use a single
condition variable per <codeclass="computeroutput"><spanclass="identifier">io_service</span></code>
instance. This addresses a potential race condition when <codeclass="computeroutput"><spanclass="identifier">run_one</span><spanclass="special">()</span></code>
is used from multiple threads.
</li>
<liclass="listitem">
Prevented integer overflow when computing timeouts based on some <codeclass="computeroutput"><spanclass="identifier">boost</span><spanclass="special">::</span><spanclass="identifier">chrono</span></code> and <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">chrono</span></code>
clocks.
</li>
<liclass="listitem">
Made further changes to <codeclass="computeroutput"><spanclass="identifier">EV_CLEAR</span></code>
handling in the kqueue backend, to address other cases where the <codeclass="computeroutput"><spanclass="identifier">close</span><spanclass="special">()</span></code>
system call may hang on Mac OS X.
</li>
<liclass="listitem">
Fixed infinite recursion in implementation of <codeclass="computeroutput"><spanclass="identifier">resolver_query_base</span><spanclass="special">::</span><spanclass="identifier">flags</span><spanclass="special">::</span><spanclass="keyword">operator</span><spanclass="special">~</span></code>.
</li>
<liclass="listitem">
Made the <codeclass="computeroutput"><spanclass="identifier">select</span></code> reactor
more efficient on Windows for large numbers of sockets.
</li>
<liclass="listitem">
Fixed a Windows-specific type-aliasing issue reported by <codeclass="literal">gcc</code>.
</li>
<liclass="listitem">
Prevented execution of compile-time-only buffer test to avoid triggering
an address sanitiser warning.
</li>
<liclass="listitem">
Disabled the <codeclass="computeroutput"><spanclass="identifier">GetQueuedCompletionStatus</span></code>
timeout workaround on recent versions of Windows.
</li>
<liclass="listitem">
Changed implementation for Windows Runtime to use <codeclass="computeroutput"><spanclass="identifier">FormatMessageW</span></code>
rather than <codeclass="computeroutput"><spanclass="identifier">FormatMessageA</span></code>,
as the Windows store does not permit the latter.
</li>
<liclass="listitem">
Added support for string-based scope IDs when using link-local multicast
addresses.
</li>
<liclass="listitem">
Changed IPv6 multicast group join to use the address's scope ID as the
interface, if an interface is not explicitly specified.
</li>
<liclass="listitem">
Fixed multicast test failure on Mac OS X and the BSDs by using a link-local
composed operations, timers, etc., should all work as normal.
</li>
<liclass="listitem">
For sockets, only client-side TCP is supported.
</li>
<liclass="listitem">
Explicit binding of a client-side TCP socket is not supported.
</li>
<liclass="listitem">
The <codeclass="computeroutput"><spanclass="identifier">cancel</span><spanclass="special">()</span></code>
function is not supported for sockets. Asynchronous operations may
only be cancelled by closing the socket.
</li>
<liclass="listitem">
Operations that use <codeclass="computeroutput"><spanclass="identifier">null_buffers</span></code>
are not supported.
</li>
<liclass="listitem">
Only <codeclass="computeroutput"><spanclass="identifier">tcp</span><spanclass="special">::</span><spanclass="identifier">no_delay</span></code> and <codeclass="computeroutput"><spanclass="identifier">socket_base</span><spanclass="special">::</span><spanclass="identifier">keep_alive</span></code>
options are supported.
</li>
<liclass="listitem">
Resolvers do not support service names, only numbers. I.e. you must
use "80" rather than "http".
</li>
<liclass="listitem">
Most resolver query flags have no effect.
</li>
</ul></div>
</li>
<liclass="listitem">
Extended the ability to use Asio without Boost to include Microsoft Visual
Studio 2012. When using a C++11 compiler, most of Asio may now be used
without a dependency on Boost header files or libraries. To use Asio in
this way, define <codeclass="computeroutput"><spanclass="identifier">ASIO_STANDALONE</span></code>
on your compiler command line or as part of the project options. This standalone
configuration has been tested for the following platforms and compilers:
Linux with g++ 4.7 or 4.8 (requires <codeclass="literal">-std=c++11</code>)
</li>
<liclass="listitem">
Mac OS X with clang++ / Xcode 4.6 (requires <codeclass="literal">-std=c++11 -stdlib=libc++</code>)
</li>
</ul></div>
</li>
<liclass="listitem">
Fixed a regression (introduced in 1.10.0) where, on some platforms, errors
from <codeclass="computeroutput"><spanclass="identifier">async_connect</span></code> were
not correctly propagated through to the completion handler.
</li>
<liclass="listitem">
Fixed a Windows-specific regression (introduced in 1.10.0) that occurs
when multiple threads are running an <codeclass="computeroutput"><spanclass="identifier">io_service</span></code>.
When the bug occurs, the result of an asynchronous operation (error and
bytes tranferred) is incorrectly discarded and zero values used instead.
For TCP sockets this results in spurious end-of-file notifications.
</li>
<liclass="listitem">
Fixed a bug in handler tracking, where it was not correctly printing out
some handler IDs.
</li>
<liclass="listitem">
Fixed the comparison used to test for successful synchronous accept operations
so that it works correctly with unsigned socket descriptors.
</li>
<liclass="listitem">
Ensured the signal number is correctly passed to the completion handler
when starting an <codeclass="computeroutput"><spanclass="identifier">async_wait</span></code>
on a signal that is already raised.
</li>
<liclass="listitem">
Suppressed a g++ 4.8+ warning about unused typedefs.
</li>
<liclass="listitem">
Enabled the move optimisation for handlers that use the default invocation
hook.
</li>
<liclass="listitem">
Clarified that programs must not issue overlapping <codeclass="computeroutput"><spanclass="identifier">async_write_at</span></code>
operations.
</li>
<liclass="listitem">
Changed the Windows <codeclass="computeroutput"><spanclass="identifier">HANDLE</span></code>
backend to treat <codeclass="computeroutput"><spanclass="identifier">ERROR_MORE_DATA</span></code>
as a non-fatal error when returned by <codeclass="computeroutput"><spanclass="identifier">GetOverlappedResult</span></code>
for a synchronous read.
</li>
<liclass="listitem">
Visual C++ language extensions use <codeclass="computeroutput"><spanclass="identifier">generic</span></code>
as a keyword. Added a workaround that renames the namespace to <codeclass="computeroutput"><spanclass="identifier">cpp_generic</span></code> when those language extensions
are in effect.
</li>
<liclass="listitem">
Fixed some asynchronous operations that missed out on getting <codeclass="computeroutput"><spanclass="identifier">async_result</span></code> support in 1.10.0. In particular,
the buffered stream templates have been updated so that they adhere to
current handler patterns.
</li>
<liclass="listitem">
Enabled move support for Microsoft Visual Studio 2012.
</li>
<liclass="listitem">
Added <codeclass="computeroutput"><spanclass="identifier">use_future</span></code> support
for Microsoft Visual Studio 2012.
</li>
<liclass="listitem">
Removed a use of <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">min</span></code> in the Windows IOCP backend to avoid
a dependency on the <codeclass="computeroutput"><spanclass="special"><</span><spanclass="identifier">algorithm</span><spanclass="special">></span></code> header.
</li>
<liclass="listitem">
Eliminated some unnecessary handler copies.
</li>
<liclass="listitem">
Fixed support for older versions of OpenSSL that do not provide the <codeclass="computeroutput"><spanclass="identifier">SSL_CTX_clear_options</span></code> function.
</li>
<liclass="listitem">
Fixed various minor and cosmetic issues in code and documentation.
Added new traits classes, <codeclass="computeroutput"><spanclass="identifier">handler_type</span></code>
and <codeclass="computeroutput"><spanclass="identifier">async_result</span></code>, that
allow the customisation of the return type of an initiating function.
</li>
<liclass="listitem">
Added the <codeclass="computeroutput"><spanclass="identifier">asio</span><spanclass="special">::</span><spanclass="identifier">spawn</span><spanclass="special">()</span></code>
function, a high-level wrapper for running stackful coroutines, based on
the Boost.Coroutine library. The <codeclass="computeroutput"><spanclass="identifier">spawn</span><spanclass="special">()</span></code> function enables programs to implement
asynchronous logic in a synchronous manner. For example: <codeclass="computeroutput"><spanclass="identifier">size_t</span><spanclass="identifier">n</span>
<spanclass="special">=</span><spanclass="identifier">my_socket</span><spanclass="special">.</span><spanclass="identifier">async_read_some</span><spanclass="special">(</span><spanclass="identifier">my_buffer</span><spanclass="special">,</span><spanclass="identifier">yield</span><spanclass="special">);</span></code>. For further information, see <aclass="link"href="overview/composition/spawn.html"title="Stackful Coroutines">Stackful
Coroutines</a>.
</li>
<liclass="listitem">
Added the <codeclass="computeroutput"><spanclass="identifier">asio</span><spanclass="special">::</span><spanclass="identifier">use_future</span></code> special value, which provides
first-class support for returning a C++11 <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">future</span></code>
from an asynchronous operation's initiating function. For example: <codeclass="computeroutput"><spanclass="identifier">future</span><spanclass="special"><</span><spanclass="identifier">size_t</span><spanclass="special">></span>
<spanclass="special">=</span><spanclass="identifier">my_socket</span><spanclass="special">.</span><spanclass="identifier">async_read_some</span><spanclass="special">(</span><spanclass="identifier">my_buffer</span><spanclass="special">,</span><spanclass="identifier">asio</span><spanclass="special">::</span><spanclass="identifier">use_future</span><spanclass="special">);</span></code>. For further information, see <aclass="link"href="overview/composition/futures.html"title="Futures">Futures</a>.
</li>
<liclass="listitem">
Promoted the stackless coroutine class and macros to be part of Asio's
documented interface, rather than part of the HTTP server 4 example. For
further information, see <aclass="link"href="overview/composition/coroutine.html"title="Stackless Coroutines">Stackless
Coroutines</a>.
</li>
<liclass="listitem">
Added a new handler hook called <codeclass="computeroutput"><spanclass="identifier">asio_handler_is_continuation</span></code>.
Asynchronous operations may represent a continuation of the asynchronous
control flow associated with the current executing handler. The <codeclass="computeroutput"><spanclass="identifier">asio_handler_is_continuation</span></code> hook can
be customised to return <codeclass="computeroutput"><spanclass="keyword">true</span></code>
if this is the case, and Asio's implementation can use this knowledge to
optimise scheduling of the new handler. To cover common cases, Asio customises
the hook for strands, <codeclass="computeroutput"><spanclass="identifier">spawn</span><spanclass="special">()</span></code> and composed asynchronous operations.
</li>
<liclass="listitem">
Added four new generic protocol classes, <codeclass="computeroutput"><spanclass="identifier">generic</span><spanclass="special">::</span><spanclass="identifier">datagram_protocol</span></code>,
and <codeclass="computeroutput"><spanclass="identifier">generic</span><spanclass="special">::</span><spanclass="identifier">stream_protocol</span></code>, which implement the
<codeclass="computeroutput"><spanclass="identifier">Protocol</span></code> type requirements,
but allow the user to specify the address family (e.g. <codeclass="computeroutput"><spanclass="identifier">AF_INET</span></code>)
and protocol type (e.g. <codeclass="computeroutput"><spanclass="identifier">IPPROTO_TCP</span></code>)
at runtime. For further information, see <aclass="link"href="overview/networking/other_protocols.html"title="Support for Other Protocols">Support
for Other Protocols</a>.
</li>
<liclass="listitem">
Added C++11 move constructors that allow the conversion of a socket (or
acceptor) into a more generic type. For example, an <codeclass="computeroutput"><spanclass="identifier">ip</span><spanclass="special">::</span><spanclass="identifier">tcp</span><spanclass="special">::</span><spanclass="identifier">socket</span></code>
can be converted into a <codeclass="computeroutput"><spanclass="identifier">generic</span><spanclass="special">::</span><spanclass="identifier">stream_protocol</span><spanclass="special">::</span><spanclass="identifier">socket</span></code>
via move construction. For further information, see <aclass="link"href="overview/networking/other_protocols.html"title="Support for Other Protocols">Support
for Other Protocols</a>.
</li>
<liclass="listitem">
Extended the <codeclass="computeroutput"><spanclass="identifier">basic_socket_acceptor</span><spanclass="special"><></span></code>'s <codeclass="computeroutput"><spanclass="identifier">accept</span><spanclass="special">()</span></code> and <codeclass="computeroutput"><spanclass="identifier">async_accept</span><spanclass="special">()</span></code> functions to allow a new connection to
be accepted directly into a socket of a more generic type. For example,
an <codeclass="computeroutput"><spanclass="identifier">ip</span><spanclass="special">::</span><spanclass="identifier">tcp</span><spanclass="special">::</span><spanclass="identifier">acceptor</span></code> can be used to accept into a
<codeclass="computeroutput"><spanclass="identifier">generic</span><spanclass="special">::</span><spanclass="identifier">stream_protocol</span><spanclass="special">::</span><spanclass="identifier">socket</span></code> object. For further information,
see <aclass="link"href="overview/networking/other_protocols.html"title="Support for Other Protocols">Support for
Other Protocols</a>.
</li>
<liclass="listitem">
Moved existing examples into a C++03-specific directory, and added a new
directory for C++11-specific examples. A limited subset of the C++03 examples
have been converted to their C++11 equivalents.
</li>
<liclass="listitem">
Add the ability to use Asio without Boost, for a limited set of platforms.
When using a C++11 compiler, most of Asio may now be used without a dependency
on Boost header files or libraries. To use Asio in this way, define <codeclass="computeroutput"><spanclass="identifier">ASIO_STANDALONE</span></code> on your compiler command
line or as part of the project options. This standalone configuration has
currently been tested for the following platforms and compilers:
Added support for SSL handshakes with re-use of data already read
from the wire. New overloads of the <codeclass="computeroutput"><spanclass="identifier">ssl</span><spanclass="special">::</span><spanclass="identifier">stream</span><spanclass="special"><></span></code> class's <codeclass="computeroutput"><spanclass="identifier">handshake</span><spanclass="special">()</span></code> and <codeclass="computeroutput"><spanclass="identifier">async_handshake</span><spanclass="special">()</span></code> functions have been added. These
accept a <codeclass="computeroutput"><spanclass="identifier">ConstBufferSequence</span></code>
to be used as initial input to the ssl engine for the handshake procedure.
</li>
<liclass="listitem">
Added support for creation of TLSv1.1 and TLSv1.2 <codeclass="computeroutput"><spanclass="identifier">ssl</span><spanclass="special">::</span><spanclass="identifier">context</span></code>
objects.
</li>
<liclass="listitem">
Added a <codeclass="computeroutput"><spanclass="identifier">set_verify_depth</span><spanclass="special">()</span></code> function to the <codeclass="computeroutput"><spanclass="identifier">ssl</span><spanclass="special">::</span><spanclass="identifier">context</span></code>
and <codeclass="computeroutput"><spanclass="identifier">ssl</span><spanclass="special">::</span><spanclass="identifier">stream</span><spanclass="special"><></span></code>
classes.
</li>
<liclass="listitem">
Added the ability to load SSL certificate and key data from memory
buffers. New functions, <codeclass="computeroutput"><spanclass="identifier">add_certificate_authority</span><spanclass="special">()</span></code>, <codeclass="computeroutput"><spanclass="identifier">use_certificate</span><spanclass="special">()</span></code>, <codeclass="computeroutput"><spanclass="identifier">use_certificate_chain</span><spanclass="special">()</span></code>, <codeclass="computeroutput"><spanclass="identifier">use_private_key</span><spanclass="special">()</span></code>, <codeclass="computeroutput"><spanclass="identifier">use_rsa_private_key</span><spanclass="special">()</span></code> and <codeclass="computeroutput"><spanclass="identifier">use_tmp_dh</span><spanclass="special">()</span></code>, have been added to the <codeclass="computeroutput"><spanclass="identifier">ssl</span><spanclass="special">::</span><spanclass="identifier">context</span></code> class.
</li>
<liclass="listitem">
Changed <codeclass="computeroutput"><spanclass="identifier">ssl</span><spanclass="special">::</span><spanclass="identifier">context</span></code> to automatically disable
SSL compression by default. To enable, use the new <codeclass="computeroutput"><spanclass="identifier">ssl</span><spanclass="special">::</span><spanclass="identifier">context</span><spanclass="special">::</span><spanclass="identifier">clear_options</span><spanclass="special">()</span></code>
function, as in <codeclass="computeroutput"><spanclass="identifier">my_context</span><spanclass="special">.</span><spanclass="identifier">clear_options</span><spanclass="special">(</span><spanclass="identifier">ssl</span><spanclass="special">::</span><spanclass="identifier">context</span><spanclass="special">::</span><spanclass="identifier">no_compression</span><spanclass="special">)</span></code>.
</li>
</ul></div>
</li>
<liclass="listitem">
Fixed a potential deadlock in <codeclass="computeroutput"><spanclass="identifier">signal_set</span></code>
implementation.
</li>
<liclass="listitem">
Fixed an error in acceptor example in documentation.
</li>
<liclass="listitem">
Fixed copy-paste errors in waitable timer documentation.
</li>
<liclass="listitem">
Added assertions to satisfy some code analysis tools.
</li>
<liclass="listitem">
Fixed a malformed <codeclass="computeroutput"><spanclass="preprocessor">#warning</span></code>
directive.
</li>
<liclass="listitem">
Fixed a potential data race in the Linux <codeclass="computeroutput"><spanclass="identifier">epoll</span></code>
implementation.
</li>
<liclass="listitem">
Fixed a Windows-specific bug, where certain operations might generate an
<codeclass="computeroutput"><spanclass="identifier">error_code</span></code> with an invalid
underlying implementation so that it can handle any <codeclass="computeroutput"><spanclass="identifier">time_point</span></code>
value without overflowing the intermediate duration objects.
</li>
<liclass="listitem">
Fixed a problem with lost thread wakeups that can occur when making concurrent
calls to <codeclass="computeroutput"><spanclass="identifier">run</span><spanclass="special">()</span></code>
and <codeclass="computeroutput"><spanclass="identifier">poll</span><spanclass="special">()</span></code>
on the same <codeclass="computeroutput"><spanclass="identifier">io_service</span></code>
object.
</li>
<liclass="listitem">
Fixed implementation of asynchronous connect operation so that it can cope
with spurious readiness notifications from the reactor.
</li>
<liclass="listitem">
Fixed a memory leak in the <codeclass="computeroutput"><spanclass="identifier">ssl</span><spanclass="special">::</span><spanclass="identifier">rfc2818_verification</span></code>
class.
</li>
<liclass="listitem">
Added a mechanism for disabling automatic Winsock initialisation. See the
header file <codeclass="literal">asio/detail/winsock_init.hpp</code> for details.
Fixed various small errors in documentation and comments.
</li>
<liclass="listitem">
Fixed an error in the example embedded in <codeclass="computeroutput"><spanclass="identifier">basic_socket</span><spanclass="special">::</span><spanclass="identifier">get_option</span></code>'s
documentation.
</li>
<liclass="listitem">
Changed to use <codeclass="computeroutput"><spanclass="keyword">long</span></code> rather
than <codeclass="computeroutput"><spanclass="keyword">int</span></code> for SSL_CTX options,
to match OpenSSL.
</li>
<liclass="listitem">
Changed to use <codeclass="computeroutput"><spanclass="identifier">_snwprintf</span></code>
to address a compile error due to the changed <codeclass="computeroutput"><spanclass="identifier">swprintf</span></code>
signature in recent versions of MinGW.
</li>
<liclass="listitem">
Fixed a deadlock that can occur on Windows when shutting down a pool of
<codeclass="computeroutput"><spanclass="identifier">io_service</span></code> threads due
to running out of work.
</li>
<liclass="listitem">
Changed UNIX domain socket example to treat errors from <codeclass="computeroutput"><spanclass="identifier">accept</span></code>
as non-fatal.
</li>
<liclass="listitem">
Added a small block recycling optimisation to improve default memory allocation
Fixed an incompatibility between <codeclass="computeroutput"><spanclass="identifier">ip</span><spanclass="special">::</span><spanclass="identifier">tcp</span><spanclass="special">::</span><spanclass="identifier">iostream</span></code>
and C++11.
</li>
<liclass="listitem">
Decorated GCC attribute names with underscores to prevent interaction with
user-defined macros.
</li>
<liclass="listitem">
Added missing <codeclass="computeroutput"><spanclass="preprocessor">#include</span><spanclass="special"><</span><spanclass="identifier">cctype</span><spanclass="special">></span></code>, needed for some versions of MinGW.
</li>
<liclass="listitem">
Changed to use <codeclass="literal">gcc</code>'s atomic builtins on ARM CPUs, when
available.
</li>
<liclass="listitem">
Changed strand destruction to be a no-op, to allow strand objects to be
destroyed after their associated <codeclass="computeroutput"><spanclass="identifier">io_service</span></code>
has been destroyed.
</li>
<liclass="listitem">
Added support for some newer versions of glibc which provide the <codeclass="computeroutput"><spanclass="identifier">epoll_create1</span><spanclass="special">()</span></code>
function but always fail with ENOSYS.
</li>
<liclass="listitem">
Changed the SSL implementation to throw an exception if SSL engine initialisation
fails.
</li>
<liclass="listitem">
Fixed another regression in <codeclass="computeroutput"><spanclass="identifier">buffered_write_stream</span></code>.
</li>
<liclass="listitem">
Implemented various minor performance improvements, primarily targeted
Changed the <codeclass="computeroutput"><spanclass="identifier">epoll_reactor</span></code>
backend to do lazy registration for <codeclass="computeroutput"><spanclass="identifier">EPOLLOUT</span></code>
events.
</li>
<liclass="listitem">
Fixed the <codeclass="computeroutput"><spanclass="identifier">epoll_reactor</span></code>
handling of out-of-band data, which was broken by an incomplete fix in
the last release.
</li>
<liclass="listitem">
Changed Asio's SSL wrapper to respect OpenSSL's <codeclass="computeroutput"><spanclass="identifier">OPENSSL_NO_ENGINE</span></code>
feature test <codeclass="computeroutput"><spanclass="preprocessor">#define</span></code>.
</li>
<liclass="listitem">
Fixed <codeclass="computeroutput"><spanclass="identifier">windows</span><spanclass="special">::</span><spanclass="identifier">object_handle</span></code> so that it works with Windows
compilers that support C++11 move semantics (such as <codeclass="literal">g++</code>).
</li>
<liclass="listitem">
Improved the performance of strand rescheduling.
</li>
<liclass="listitem">
Added support for <codeclass="literal">g++</code> 4.7 when compiling in C++11 mode.
</li>
<liclass="listitem">
Fixed a problem where <codeclass="computeroutput"><spanclass="identifier">signal_set</span></code>
handlers were not being delivered when the <codeclass="computeroutput"><spanclass="identifier">io_service</span></code>
was constructed with a <codeclass="computeroutput"><spanclass="identifier">concurrency_hint</span></code>
Added a new class template <codeclass="computeroutput"><spanclass="identifier">basic_waitable_timer</span></code>
based around the C++11 clock type requirements. It may be used with the
clocks from the C++11 <codeclass="computeroutput"><spanclass="special"><</span><spanclass="identifier">chrono</span><spanclass="special">></span></code>
library facility or, if those are not available, Boost.Chrono. The typedefs
<codeclass="computeroutput"><spanclass="identifier">steady_timer</span></code> and <codeclass="computeroutput"><spanclass="identifier">system_timer</span></code> may be used to create timer
objects for the standard clock types.
</li>
<liclass="listitem">
Added a new <codeclass="computeroutput"><spanclass="identifier">windows</span><spanclass="special">::</span><spanclass="identifier">object_handle</span></code> class for performing waits
on Windows kernel objects. Thanks go to Boris Schaeling for contributing
substantially to the development of this feature.
</li>
<liclass="listitem">
On Linux, <codeclass="computeroutput"><spanclass="identifier">connect</span><spanclass="special">()</span></code>
can return EAGAIN in certain circumstances. Remapped this to another error
so that it doesn't look like a non-blocking operation.
</li>
<liclass="listitem">
Fixed a compile error on NetBSD.
</li>
<liclass="listitem">
Fixed deadlock on Mac OS X.
</li>
<liclass="listitem">
Fixed a regression in <codeclass="computeroutput"><spanclass="identifier">buffered_write_stream</span></code>.
</li>
<liclass="listitem">
Fixed a non-paged pool "leak" on Windows when an <codeclass="computeroutput"><spanclass="identifier">io_service</span></code> is repeatedly run without
anything to do.
</li>
<liclass="listitem">
Reverted earlier change to allow some speculative operations to be performed
without holding the lock, as it introduced a race condition in some multithreaded
scenarios.
</li>
<liclass="listitem">
Fixed a bug where the second buffer in an array of two buffers may be ignored
Using thread-local operation queues in single-threaded use cases
(i.e. when <codeclass="computeroutput"><spanclass="identifier">concurrency_hint</span></code>
is 1) to eliminate a lock/unlock pair.
</li>
<liclass="listitem">
Allowing some <codeclass="computeroutput"><spanclass="identifier">epoll_reactor</span></code>
speculative operations to be performed without holding the lock.
</li>
<liclass="listitem">
Improving locality of reference by performing an <codeclass="computeroutput"><spanclass="identifier">epoll_reactor</span></code>'s
I/O operation immediately before the corresponding handler is called.
This also improves scalability across CPUs when multiple threads
are running the <codeclass="computeroutput"><spanclass="identifier">io_service</span></code>.
</li>
<liclass="listitem">
Specialising asynchronous read and write operations for buffer sequences
that are arrays (<codeclass="computeroutput"><spanclass="identifier">boost</span><spanclass="special">::</span><spanclass="identifier">array</span></code>
or <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">array</span></code>) of exactly two buffers.
</li>
</ul></div>
</li>
<liclass="listitem">
Fixed a compile error in the regex overload of <codeclass="computeroutput"><spanclass="identifier">async_read_until</span></code>.
</li>
<liclass="listitem">
Fixed a Windows-specific compile error by explicitly specifying the <codeclass="computeroutput"><spanclass="identifier">signal</span><spanclass="special">()</span></code>
function from the global namespace.
</li>
<liclass="listitem">
Changed the <codeclass="computeroutput"><spanclass="identifier">deadline_timer</span></code>
implementation so that it does not read the clock unless the timer heap
is non-empty.
</li>
<liclass="listitem">
Changed the SSL stream's buffers' sizes so that they are large enough to
hold a complete TLS record.
</li>
<liclass="listitem">
Fixed the behaviour of the synchronous <codeclass="computeroutput"><spanclass="identifier">null_buffers</span></code>
operations so that they obey the user's non-blocking setting.
</li>
<liclass="listitem">
Changed to set the size of the select <codeclass="computeroutput"><spanclass="identifier">fd_set</span></code>
at runtime when using Windows.
</li>
<liclass="listitem">
Disabled an MSVC warning due to const qualifier being applied to function
type.
</li>
<liclass="listitem">
Fixed a crash that occurs when using the Intel C++ compiler.
</li>
<liclass="listitem">
Changed the initialisation of the OpenSSL library so that it supports all
available algorithms.
</li>
<liclass="listitem">
Fixed the SSL error mapping used when the session is gracefully shut down.
</li>
<liclass="listitem">
Added some latency test programs.
</li>
<liclass="listitem">
Clarified that a read operation ends when the buffer is full.
</li>
<liclass="listitem">
Fixed an exception safety issue in <codeclass="computeroutput"><spanclass="identifier">epoll_reactor</span></code>
initialisation.
</li>
<liclass="listitem">
Made the number of strand implementations configurable by defining <codeclass="computeroutput"><spanclass="special">(</span><spanclass="identifier">BOOST_</span><spanclass="special">)</span><spanclass="identifier">ASIO_STRAND_IMPLEMENTATIONS</span></code>
to the desired number.
</li>
<liclass="listitem">
Added support for a new <codeclass="computeroutput"><spanclass="special">(</span><spanclass="identifier">BOOST_</span><spanclass="special">)</span><spanclass="identifier">ASIO_ENABLE_SEQUENTIAL_STRAND_ALLOCATION</span></code>
flag which switches the allocation of strand implementations to use a round-robin
approach rather than hashing.
</li>
<liclass="listitem">
Fixed potential strand starvation issue that can occur when <codeclass="computeroutput"><spanclass="identifier">strand</span><spanclass="special">.</span><spanclass="identifier">post</span><spanclass="special">()</span></code>
Improved support for C++0x move construction to further reduce copying
of handler objects. In certain designs it is possible to eliminate virtually
all copies. Move support is now enabled when compiling in <codeclass="literal">-std=c++0x</code>
mode on g++ 4.5 or higher.
</li>
<liclass="listitem">
Added build support for platforms that don't provide either of <codeclass="computeroutput"><spanclass="identifier">signal</span><spanclass="special">()</span></code>
or <codeclass="computeroutput"><spanclass="identifier">sigaction</span><spanclass="special">()</span></code>.
</li>
<liclass="listitem">
Changed to use C++0x variadic templates when they are available, rather
than generating function overloads using the Boost.Preprocessor library.
</li>
<liclass="listitem">
Ensured the value of <codeclass="computeroutput"><spanclass="identifier">errno</span></code>
is preserved across the implementation's signal handler.
</li>
<liclass="listitem">
On Windows, ensured the count of outstanding work is decremented for abandoned
operations (i.e. operations that are being cleaned up within the <codeclass="computeroutput"><spanclass="identifier">io_service</span></code> destructor).
</li>
<liclass="listitem">
Fixed behaviour of zero-length reads and writes in the new SSL implementation.
</li>
<liclass="listitem">
Added support for building with OpenSSL 1.0 when <codeclass="computeroutput"><spanclass="identifier">OPENSSL_NO_SSL2</span></code>
is defined.
</li>
<liclass="listitem">
Changed most examples to treat a failure by an accept operation as non-fatal.
</li>
<liclass="listitem">
Fixed an error in the <codeclass="literal">tick_count_timer</code> example by making
the duration type signed. Previously, a wait on an already-passed deadline
Added new <codeclass="computeroutput"><spanclass="identifier">asio</span><spanclass="special">::</span><spanclass="identifier">buffer</span><spanclass="special">()</span></code>
overloads for <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">array</span></code>, when available. The support is
automatically enabled when compiling in <codeclass="literal">-std=c++0x</code> mode
on g++ 4.3 or higher, or when using MSVC 10. The support may be explicitly
enabled by defining <codeclass="computeroutput"><spanclass="special">(</span><spanclass="identifier">BOOST_</span><spanclass="special">)</span><spanclass="identifier">ASIO_HAS_STD_ARRAY</span></code>,
or disabled by defining <codeclass="computeroutput"><spanclass="special">(</span><spanclass="identifier">BOOST_</span><spanclass="special">)</span><spanclass="identifier">ASIO_DISABLE_STD_ARRAY</span></code>.
</li>
<liclass="listitem">
Changed to use the C++0x standard library templates <codeclass="computeroutput"><spanclass="identifier">array</span></code>,
<codeclass="computeroutput"><spanclass="identifier">shared_ptr</span></code>, <codeclass="computeroutput"><spanclass="identifier">weak_ptr</span></code> and <codeclass="computeroutput"><spanclass="identifier">atomic</span></code>
when they are available, rather than the Boost equivalents.
</li>
<liclass="listitem">
Support for <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">error_code</span></code> and <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">system_error</span></code>
is no longer enabled by default for g++ 4.5, as that compiler's standard
library does not implement <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">system_error</span><spanclass="special">::</span><spanclass="identifier">what</span><spanclass="special">()</span></code> correctly.
Added support for C++0x move construction and assignment to sockets, serial
ports, POSIX descriptors and Windows handles.
</li>
<liclass="listitem">
Added support for the <codeclass="computeroutput"><spanclass="identifier">fork</span><spanclass="special">()</span></code> system call. Programs that use <codeclass="computeroutput"><spanclass="identifier">fork</span><spanclass="special">()</span></code>
must call <codeclass="computeroutput"><spanclass="identifier">io_service</span><spanclass="special">.</span><spanclass="identifier">notify_fork</span><spanclass="special">()</span></code>
at the appropriate times. Two new examples have been added showing how
to use this feature.
</li>
<liclass="listitem">
Cleaned up the handling of errors reported by the <codeclass="computeroutput"><spanclass="identifier">close</span><spanclass="special">()</span></code> system call. In particular, assume that
most operating systems won't have <codeclass="computeroutput"><spanclass="identifier">close</span><spanclass="special">()</span></code> fail with <codeclass="computeroutput"><spanclass="identifier">EWOULDBLOCK</span></code>,
but if it does then set the blocking mode and restart the call. If any
other error occurs, assume the descriptor is closed.
</li>
<liclass="listitem">
The kqueue flag <codeclass="computeroutput"><spanclass="identifier">EV_ONESHOT</span></code>
seems to cause problems on some versions of Mac OS X, with the <codeclass="computeroutput"><spanclass="identifier">io_service</span></code> destructor getting stuck inside
the <codeclass="computeroutput"><spanclass="identifier">close</span><spanclass="special">()</span></code>
system call. Changed the kqueue backend to use <codeclass="computeroutput"><spanclass="identifier">EV_CLEAR</span></code>
instead.
</li>
<liclass="listitem">
Changed exception reporting to include the function name in exception
Fixed an insufficient initialisers warning with MinGW.
</li>
<liclass="listitem">
Changed the <codeclass="computeroutput"><spanclass="identifier">shutdown_service</span><spanclass="special">()</span></code> member functions to be private.
</li>
<liclass="listitem">
Added archetypes for testing socket option functions.
</li>
<liclass="listitem">
Added a missing lock in <codeclass="computeroutput"><spanclass="identifier">signal_set_service</span><spanclass="special">::</span><spanclass="identifier">cancel</span><spanclass="special">()</span></code>.
</li>
<liclass="listitem">
Fixed a copy/paste error in <codeclass="computeroutput"><spanclass="identifier">SignalHandler</span></code>
example.
</li>
<liclass="listitem">
Added the inclusion of the signal header to <codeclass="computeroutput"><spanclass="identifier">signal_set_service</span><spanclass="special">.</span><spanclass="identifier">hpp</span></code>
so that constants like <codeclass="computeroutput"><spanclass="identifier">NSIG</span></code>
may be used.
</li>
<liclass="listitem">
Changed the <codeclass="computeroutput"><spanclass="identifier">signal_set_service</span></code>
implementation so that it doesn't assume that <codeclass="computeroutput"><spanclass="identifier">SIGRTMAX</span></code>
is a compile-time constant.
</li>
<liclass="listitem">
Changed the Boost.Asio examples so that they don't use Boost.Thread's convenience
header. Use the header file that is specifically for the boost::thread
Added support for signal handling, using a new class called <codeclass="computeroutput"><spanclass="identifier">signal_set</span></code>. Programs may add one or more
signals to the set, and then perform an <codeclass="computeroutput"><spanclass="identifier">async_wait</span><spanclass="special">()</span></code> operation. The specified handler will
be called when one of the signals occurs. The same signal number may registered
with multiple <codeclass="computeroutput"><spanclass="identifier">signal_set</span></code>
objects, however the signal number must be used only with Asio.
</li>
<liclass="listitem">
Added handler tracking, a new debugging aid. When enabled by defining
Asio writes debugging output to the standard error stream. The output records
asynchronous operations and the relationships between their handlers. It
may be post-processed using the included <codeclass="literal">handlerviz.pl</code>
tool to create a visual representation of the handlers (requires GraphViz).
</li>
<liclass="listitem">
Fixed a bug in <codeclass="computeroutput"><spanclass="identifier">asio</span><spanclass="special">::</span><spanclass="identifier">streambuf</span></code> where the <codeclass="computeroutput"><spanclass="identifier">consume</span><spanclass="special">()</span></code> function did not always update the internal
buffer pointers correctly. The problem may occur when the <codeclass="computeroutput"><spanclass="identifier">asio</span><spanclass="special">::</span><spanclass="identifier">streambuf</span></code> is filled with data using the
standard C++ member functions such as <codeclass="computeroutput"><spanclass="identifier">sputn</span><spanclass="special">()</span></code>. (Note: the problem does not manifest
when the streambuf is populated by the Asio free functions <codeclass="computeroutput"><spanclass="identifier">read</span><spanclass="special">()</span></code>,
or <codeclass="computeroutput"><spanclass="identifier">async_read_until</span><spanclass="special">()</span></code>.)
</li>
<liclass="listitem">
Fixed a bug on kqueue-based platforms, where reactor read operations that
return false from their <codeclass="computeroutput"><spanclass="identifier">perform</span><spanclass="special">()</span></code> function are not correctly re-registered
with kqueue.
</li>
<liclass="listitem">
Support for <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">error_code</span></code> and <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">system_error</span></code>
is no longer enabled by default for MSVC10, as that compiler's standard
library does not implement <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">system_error</span><spanclass="special">::</span><spanclass="identifier">what</span><spanclass="special">()</span></code> correctly.
</li>
<liclass="listitem">
Modified the <codeclass="computeroutput"><spanclass="identifier">buffers_iterator</span><spanclass="special"><></span></code> and <codeclass="computeroutput"><spanclass="identifier">ip</span><spanclass="special">::</span><spanclass="identifier">basic_resolver_iterator</span></code>
classes so that the value_type typedefs are non-const byte types.
Added support for timeouts on socket iostreams, such as <codeclass="computeroutput"><spanclass="identifier">ip</span><spanclass="special">::</span><spanclass="identifier">tcp</span><spanclass="special">::</span><spanclass="identifier">iostream</span></code>.
A timeout is set by calling <codeclass="computeroutput"><spanclass="identifier">expires_at</span><spanclass="special">()</span></code> or <codeclass="computeroutput"><spanclass="identifier">expires_from_now</span><spanclass="special">()</span></code> to establish a deadline. Any socket operations
which occur past the deadline will put the iostream into a bad state.
</li>
<liclass="listitem">
Added a new <codeclass="computeroutput"><spanclass="identifier">error</span><spanclass="special">()</span></code>
member function to socket iostreams, for retrieving the error code from
the most recent system call.
</li>
<liclass="listitem">
Added a new <codeclass="computeroutput"><spanclass="identifier">basic_deadline_timer</span><spanclass="special">::</span><spanclass="identifier">cancel_one</span><spanclass="special">()</span></code> function. This function lets you cancel
a single waiting handler on a timer. Handlers are cancelled in FIFO order.
</li>
<liclass="listitem">
Added a new <codeclass="computeroutput"><spanclass="identifier">transfer_exactly</span><spanclass="special">()</span></code> completion condition. This can be used
to send or receive a specified number of bytes even if the total size of
the buffer (or buffer sequence) is larger.
</li>
<liclass="listitem">
Added new free functions <codeclass="computeroutput"><spanclass="identifier">connect</span><spanclass="special">()</span></code> and <codeclass="computeroutput"><spanclass="identifier">async_connect</span><spanclass="special">()</span></code>. These operations try each endpoint in
a list until the socket is successfully connected.
</li>
<liclass="listitem">
Extended the <codeclass="computeroutput"><spanclass="identifier">buffer_size</span><spanclass="special">()</span></code> function so that it works for buffer
sequences in addition to individual buffers.
</li>
<liclass="listitem">
Added a new <codeclass="computeroutput"><spanclass="identifier">buffer_copy</span><spanclass="special">()</span></code> function that can be used to copy the
raw bytes between individual buffers and buffer sequences.
</li>
<liclass="listitem">
Added new non-throwing overloads of <codeclass="computeroutput"><spanclass="identifier">read</span><spanclass="special">()</span></code>, <codeclass="computeroutput"><spanclass="identifier">read_at</span><spanclass="special">()</span></code>, <codeclass="computeroutput"><spanclass="identifier">write</span><spanclass="special">()</span></code> and <codeclass="computeroutput"><spanclass="identifier">write_at</span><spanclass="special">()</span></code> that do not require a completion condition.
</li>
<liclass="listitem">
Added friendlier compiler errors for when a completion handler does not
meet the necessary type requirements. When C++0x is available (currently
supported for g++ 4.5 or later, and MSVC 10), <codeclass="computeroutput"><spanclass="keyword">static_assert</span></code>
is also used to generate an informative error message. This checking may
be disabled by defining <codeclass="computeroutput"><spanclass="special">(</span><spanclass="identifier">BOOST_</span><spanclass="special">)</span><spanclass="identifier">ASIO_DISABLE_HANDLER_TYPE_REQUIREMENTS</span></code>.
</li>
<liclass="listitem">
Added support for using <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">error_code</span></code>
and <codeclass="computeroutput"><spanclass="identifier">std</span><spanclass="special">::</span><spanclass="identifier">system_error</span></code>, when available. The support
is automatically enabled when compiling in <codeclass="literal">-std=c++0x</code>
mode on g++ 4.5 or higher, or when using MSVC 10. The support may be explicitly
enabled by defining <codeclass="computeroutput"><spanclass="identifier">ASIO_HAS_STD_SYSTEM_ERROR</span></code>,
or disabled by defining <codeclass="computeroutput"><spanclass="identifier">ASIO_DISABLE_STD_SYSTEM_ERROR</span></code>.
(Available in non-Boost version of Asio only.)
</li>
<liclass="listitem">
Made the <codeclass="computeroutput"><spanclass="identifier">is_loopback</span><spanclass="special">()</span></code>,
and <codeclass="computeroutput"><spanclass="identifier">is_multicast</span><spanclass="special">()</span></code>
functions consistently available across the <codeclass="computeroutput"><spanclass="identifier">ip</span><spanclass="special">::</span><spanclass="identifier">address</span></code>,
<codeclass="computeroutput"><spanclass="identifier">ip</span><spanclass="special">::</span><spanclass="identifier">address_v4</span></code> and <codeclass="computeroutput"><spanclass="identifier">ip</span><spanclass="special">::</span><spanclass="identifier">address_v6</span></code>
classes.
</li>
<liclass="listitem">
Added new <codeclass="computeroutput"><spanclass="identifier">non_blocking</span><spanclass="special">()</span></code> functions for managing the non-blocking
behaviour of a socket or descriptor. The <codeclass="computeroutput"><spanclass="identifier">io_control</span><spanclass="special">()</span></code> commands named <codeclass="computeroutput"><spanclass="identifier">non_blocking_io</span></code>
are now deprecated in favour of these new functions.
</li>
<liclass="listitem">
Added new <codeclass="computeroutput"><spanclass="identifier">native_non_blocking</span><spanclass="special">()</span></code> functions for managing the non-blocking
mode of the underlying socket or descriptor. These functions are intended
to allow the encapsulation of arbitrary non-blocking system calls as asynchronous
operations, in a way that is transparent to the user of the socket object.
The functions have no effect on the behaviour of the synchronous operations
of the socket or descriptor.
</li>
<liclass="listitem">
Added the <codeclass="computeroutput"><spanclass="identifier">io_control</span><spanclass="special">()</span></code>
member function for socket acceptors.
</li>
<liclass="listitem">
For consistency with the C++0x standard library, deprecated the <codeclass="computeroutput"><spanclass="identifier">native_type</span></code> typedefs in favour of <codeclass="computeroutput"><spanclass="identifier">native_handle_type</span></code>, and the <codeclass="computeroutput"><spanclass="identifier">native</span><spanclass="special">()</span></code>
member functions in favour of <codeclass="computeroutput"><spanclass="identifier">native_handle</span><spanclass="special">()</span></code>.
</li>
<liclass="listitem">
Added a <codeclass="computeroutput"><spanclass="identifier">release</span><spanclass="special">()</span></code>
member function to posix descriptors. This function releases ownership
of the underlying native descriptor to the caller.
</li>
<liclass="listitem">
Added support for sequenced packet sockets (<codeclass="computeroutput"><spanclass="identifier">SOCK_SEQPACKET</span></code>).
</li>
<liclass="listitem">
Added a new <codeclass="computeroutput"><spanclass="identifier">io_service</span><spanclass="special">::</span><spanclass="identifier">stopped</span><spanclass="special">()</span></code> function that can be used to determine
whether the <codeclass="computeroutput"><spanclass="identifier">io_service</span></code>
has stopped (i.e. a <codeclass="computeroutput"><spanclass="identifier">reset</span><spanclass="special">()</span></code> call is needed prior to any further calls
to <codeclass="computeroutput"><spanclass="identifier">run</span><spanclass="special">()</span></code>,
or <codeclass="computeroutput"><spanclass="identifier">poll_one</span><spanclass="special">()</span></code>).
</li>
<liclass="listitem">
Reduced the copying of handler function objects.
</li>
<liclass="listitem">
Added support for C++0x move construction to further reduce copying of
handler objects. Move support is enabled when compiling in <codeclass="literal">-std=c++0x</code>
mode on g++ 4.5 or higher, or when using MSVC10.
</li>
<liclass="listitem">
Removed the dependency on OS-provided macros for the well-known IPv4 and
IPv6 addresses. This should eliminate the annoying "missing braces
around initializer" warnings.
</li>
<liclass="listitem">
Reduced the size of <codeclass="computeroutput"><spanclass="identifier">ip</span><spanclass="special">::</span><spanclass="identifier">basic_endpoint</span><spanclass="special"><></span></code> objects (such as <codeclass="computeroutput"><spanclass="identifier">ip</span><spanclass="special">::</span><spanclass="identifier">tcp</span><spanclass="special">::</span><spanclass="identifier">endpoint</span></code> and <codeclass="computeroutput"><spanclass="identifier">ip</span><spanclass="special">::</span><spanclass="identifier">udp</span><spanclass="special">::</span><spanclass="identifier">endpoint</span></code>).
</li>
<liclass="listitem">
Changed the reactor backends to assume that any descriptors or sockets
added using <codeclass="computeroutput"><spanclass="identifier">assign</span><spanclass="special">()</span></code>
may have been <codeclass="computeroutput"><spanclass="identifier">dup</span><spanclass="special">()</span></code>-ed,
and so require explicit deregistration from the reactor.
</li>
<liclass="listitem">
Changed the SSL error category to return error strings from the OpenSSL
library.
</li>
<liclass="listitem">
Changed the separate compilation support such that, to use Asio's SSL capabilities,
you should also include 'asio/ssl/impl/src.hpp` in one source file in your
program.
</li>
<liclass="listitem">
Removed the deprecated member functions named <codeclass="computeroutput"><spanclass="identifier">io_service</span><spanclass="special">()</span></code>. The <codeclass="computeroutput"><spanclass="identifier">get_io_service</span><spanclass="special">()</span></code> member functions should be used instead.
</li>
<liclass="listitem">
Removed the deprecated typedefs <codeclass="computeroutput"><spanclass="identifier">resolver_query</span></code>
and <codeclass="computeroutput"><spanclass="identifier">resolver_iterator</span></code> from
the <codeclass="computeroutput"><spanclass="identifier">ip</span><spanclass="special">::</span><spanclass="identifier">tcp</span></code>, <codeclass="computeroutput"><spanclass="identifier">ip</span><spanclass="special">::</span><spanclass="identifier">udp</span></code>
and <codeclass="computeroutput"><spanclass="identifier">ip</span><spanclass="special">::</span><spanclass="identifier">icmp</span></code> classes.
</li>
<liclass="listitem">
Fixed a compile error on some versions of g++ due to anonymous enums.
</li>
<liclass="listitem">
Added an explicit cast to the <codeclass="computeroutput"><spanclass="identifier">FIONBIO</span></code>
constant to int to suppress a compiler warning on some platforms.
</li>
<liclass="listitem">
Fixed warnings reported by g++'s <codeclass="literal">-Wshadow</code> compiler option.
Fixed an integer overflow problem that occurs when <codeclass="computeroutput"><spanclass="identifier">ip</span><spanclass="special">::</span><spanclass="identifier">address_v4</span><spanclass="special">::</span><spanclass="identifier">broadcast</span><spanclass="special">()</span></code> is used on 64-bit platforms.
</li>
<liclass="listitem">
Fixed a problem on older Linux kernels (where epoll is used without <codeclass="computeroutput"><spanclass="identifier">timerfd</span></code> support) that prevents timely
delivery of <codeclass="computeroutput"><spanclass="identifier">deadline_timer</span></code>
handlers, after the program has been running for some time.
Fixed a problem on kqueue-based platforms where a <codeclass="computeroutput"><spanclass="identifier">deadline_timer</span></code>
may never fire if the <codeclass="computeroutput"><spanclass="identifier">io_service</span></code>
is running in a background thread.
</li>
<liclass="listitem">
Fixed a const-correctness issue that prevented valid uses of <codeclass="computeroutput"><spanclass="identifier">has_service</span><spanclass="special"><></span></code>
from compiling.
</li>
<liclass="listitem">
Fixed MinGW cross-compilation.
</li>
<liclass="listitem">
Removed dependency on deprecated Boost.System functions (Boost.Asio only).
Redefined <codeclass="computeroutput"><spanclass="identifier">Protocol</span></code> and
<codeclass="computeroutput"><spanclass="identifier">id</span></code> to avoid clashing with
Objective-C++ keywords.
</li>
<liclass="listitem">
Fixed a <codeclass="computeroutput"><spanclass="identifier">vector</span></code> reallocation
performance issue that can occur when there are many active <codeclass="computeroutput"><spanclass="identifier">deadline_timer</span></code> objects.
</li>
<liclass="listitem">
Fixed the kqueue backend so that it compiles on NetBSD.
</li>
<liclass="listitem">
Fixed the socket <codeclass="computeroutput"><spanclass="identifier">io_control</span><spanclass="special">()</span></code> implementation on 64-bit Mac OS X and
BSD platforms.
</li>
<liclass="listitem">
Fixed a Windows-specific problem where failures from <codeclass="computeroutput"><spanclass="identifier">accept</span><spanclass="special">()</span></code> are incorrectly treated as successes.
</li>
<liclass="listitem">
Deprecated the separate compilation header <codeclass="computeroutput"><spanclass="identifier">asio</span><spanclass="special">/</span><spanclass="identifier">impl</span><spanclass="special">/</span><spanclass="identifier">src</span><spanclass="special">.</span><spanclass="identifier">cpp</span></code>
in favour of <codeclass="computeroutput"><spanclass="identifier">asio</span><spanclass="special">/</span><spanclass="identifier">impl</span><spanclass="special">/</span><spanclass="identifier">src</span><spanclass="special">.</span><spanclass="identifier">hpp</span></code>.
Reduced compile times. (Note that some programs may need to add additional
<codeclass="computeroutput"><spanclass="preprocessor">#include</span></code>s, e.g. if the
program uses boost::array but does not explicitly include <codeclass="computeroutput"><spanclass="special"><</span><spanclass="identifier">boost</span><spanclass="special">/</span><spanclass="identifier">array</span><spanclass="special">.</span><spanclass="identifier">hpp</span><spanclass="special">></span></code>.)
Improved multiprocessor scalability on Windows by using a dedicated hidden
thread to wait for timers.
</li>
<liclass="listitem">
Improved performance of <codeclass="computeroutput"><spanclass="identifier">asio</span><spanclass="special">::</span><spanclass="identifier">streambuf</span></code>
with <codeclass="computeroutput"><spanclass="identifier">async_read</span><spanclass="special">()</span></code>
and <codeclass="computeroutput"><spanclass="identifier">async_read_until</span><spanclass="special">()</span></code>.
These read operations now use the existing capacity of the <codeclass="computeroutput"><spanclass="identifier">streambuf</span></code> when reading, rather than limiting
the read to 512 bytes.
</li>
<liclass="listitem">
Added optional separate compilation. To enable, include <codeclass="computeroutput"><spanclass="identifier">asio</span><spanclass="special">/</span><spanclass="identifier">impl</span><spanclass="special">/</span><spanclass="identifier">src</span><spanclass="special">.</span><spanclass="identifier">cpp</span></code>
in one source file in a program, then build the program with <codeclass="computeroutput"><spanclass="special">(</span><spanclass="identifier">BOOST_</span><spanclass="special">)</span><spanclass="identifier">ASIO_SEPARATE_COMPILATION</span></code>
defined in the project/compiler settings. Alternatively, <codeclass="computeroutput"><spanclass="special">(</span><spanclass="identifier">BOOST_</span><spanclass="special">)</span><spanclass="identifier">ASIO_DYN_LINK</span></code>
may be defined to build a separately-compiled Asio as part of a shared
library.
</li>
<liclass="listitem">
Added new macro <codeclass="computeroutput"><spanclass="special">(</span><spanclass="identifier">BOOST_</span><spanclass="special">)</span><spanclass="identifier">ASIO_DISABLE_FENCED_BLOCK</span></code>
to permit the disabling of memory fences around completion handlers, even
if thread support is enabled.
</li>
<liclass="listitem">
Reworked timeout examples to better illustrate typical use cases.
</li>
<liclass="listitem">
Ensured that handler arguments are passed as const types.
</li>
<liclass="listitem">
Fixed incorrect parameter order in <codeclass="computeroutput"><spanclass="identifier">null_buffers</span></code>
variant of <codeclass="computeroutput"><spanclass="identifier">async_send_to</span></code>.
</li>
<liclass="listitem">
Ensured unsigned char is used with <codeclass="computeroutput"><spanclass="identifier">isdigit</span></code>
in <codeclass="computeroutput"><spanclass="identifier">getaddrinfo</span></code> emulation.
</li>
<liclass="listitem">
Fixed handling of very small but non-zero timeouts.
</li>
<liclass="listitem">
Fixed crash that occurred when an empty buffer sequence was passed to a
composed read or write operation.
</li>
<liclass="listitem">
Added missing operator+ overload in <codeclass="computeroutput"><spanclass="identifier">buffers_iterator</span></code>.
</li>
<liclass="listitem">
Implemented cancellation of <codeclass="computeroutput"><spanclass="identifier">null_buffers</span></code>
Extended the guarantee that background threads don't call user code to
all asynchronous operations.
</li>
<liclass="listitem">
Changed to use edge-triggered epoll on Linux.
</li>
<liclass="listitem">
Changed to use <codeclass="computeroutput"><spanclass="identifier">timerfd</span></code>
for dispatching timers on Linux, when available.
</li>
<liclass="listitem">
Changed to use one-shot notifications with kqueue on Mac OS X and BSD platforms.
</li>
<liclass="listitem">
Added a bitmask type <codeclass="computeroutput"><spanclass="identifier">ip</span><spanclass="special">::</span><spanclass="identifier">resolver_query_base</span><spanclass="special">::</span><spanclass="identifier">flags</span></code>
as per the TR2 proposal. This type prevents implicit conversion from <codeclass="computeroutput"><spanclass="keyword">int</span></code> to <codeclass="computeroutput"><spanclass="identifier">flags</span></code>,
allowing the compiler to catch cases where users incorrectly pass a numeric
for all Windows compilers. Users can define <codeclass="computeroutput"><spanclass="special">(</span><spanclass="identifier">BOOST_</span><spanclass="special">)</span><spanclass="identifier">ASIO_NO_NOMINMAX</span></code> to suppress this definition.
</li>
<liclass="listitem">
Fixed a bug where 0-byte asynchronous reads were incorrectly passing an
<codeclass="computeroutput"><spanclass="identifier">error</span><spanclass="special">::</span><spanclass="identifier">eof</span></code> result to the completion handler.
</li>
<liclass="listitem">
Changed the <codeclass="computeroutput"><spanclass="identifier">io_control</span><spanclass="special">()</span></code> member functions to always call <codeclass="computeroutput"><spanclass="identifier">ioctl</span></code> on the underlying descriptor when
modifying blocking mode.
</li>
<liclass="listitem">
Changed the resolver implementation so that it no longer requires the typedefs
<codeclass="computeroutput"><spanclass="identifier">InternetProtocol</span><spanclass="special">::</span><spanclass="identifier">resolver_query</span></code> and <codeclass="computeroutput"><spanclass="identifier">InternetProtocol</span><spanclass="special">::</span><spanclass="identifier">resolver_iterator</span></code>,
as neither typedef is part of the documented <codeclass="computeroutput"><spanclass="identifier">InternetProtocol</span></code>
requirements. The corresponding typedefs in the <codeclass="computeroutput"><spanclass="identifier">ip</span><spanclass="special">::</span><spanclass="identifier">tcp</span></code>,
<codeclass="computeroutput"><spanclass="identifier">ip</span><spanclass="special">::</span><spanclass="identifier">udp</span></code> and <codeclass="computeroutput"><spanclass="identifier">ip</span><spanclass="special">::</span><spanclass="identifier">icmp</span></code>
classes have been deprecated.
</li>
<liclass="listitem">
Fixed out-of-band handling for reactors not based on <codeclass="computeroutput"><spanclass="identifier">select</span><spanclass="special">()</span></code>.
</li>
<liclass="listitem">
Added new <codeclass="computeroutput"><spanclass="special">(</span><spanclass="identifier">BOOST_</span><spanclass="special">)</span><spanclass="identifier">ASIO_DISABLE_THREADS</span></code>
macro that allows Asio's threading support to be independently disabled.
Added a new HTTP Server 4 example illustrating the use of stackless coroutines
with Asio.
</li>
<liclass="listitem">
Changed handler allocation and invocation to use <codeclass="computeroutput"><spanclass="identifier">boost</span><spanclass="special">::</span><spanclass="identifier">addressof</span></code>
to get the address of handler objects, rather than applying <codeclass="computeroutput"><spanclass="keyword">operator</span><spanclass="special">&</span></code>
directly.
</li>
<liclass="listitem">
Restricted MSVC buffer debugging workaround to 2008, as it causes a crash
with 2010 beta 2.
</li>
<liclass="listitem">
Fixed a problem with the lifetime of handler memory, where Windows needs
the <codeclass="computeroutput"><spanclass="identifier">OVERLAPPED</span></code> structure
to be valid until both the initiating function call has returned and the
completion packet has been delivered.
</li>
<liclass="listitem">
Don't block signals while performing system calls, but instead restart
the calls if they are interrupted.
</li>
<liclass="listitem">
Documented the guarantee made by strand objects with respect to order of
handler invocation.
</li>
<liclass="listitem">
Changed strands to use a pool of implementations, to make copying of strands
cheaper.
</li>
<liclass="listitem">
Ensured that kqueue support is enabled for BSD platforms.
</li>
<liclass="listitem">
Added a <codeclass="computeroutput"><spanclass="identifier">boost_</span></code> prefix to
the <codeclass="computeroutput"><spanclass="keyword">extern</span><spanclass="string">"C"</span></code>
thread entry point function.
</li>
<liclass="listitem">
In <codeclass="computeroutput"><spanclass="identifier">getaddrinfo</span></code> emulation,
only check the socket type (<codeclass="computeroutput"><spanclass="identifier">SOCK_STREAM</span></code>
or <codeclass="computeroutput"><spanclass="identifier">SOCK_DGRAM</span></code>) if a service
name has been specified. This should allow the emulation to work with raw
sockets.
</li>
<liclass="listitem">
Added a workaround for some broken Windows firewalls that make a socket
appear bound to 0.0.0.0 when it is in fact bound to 127.0.0.1.
</li>
<liclass="listitem">
Applied a fix for reported excessive CPU usage under Solaris.
</li>
<liclass="listitem">
Added some support for platforms that use older compilers such as g++ 2.95.
Added a new ping example to illustrate the use of ICMP sockets.
</li>
<liclass="listitem">
Changed the <codeclass="computeroutput"><spanclass="identifier">buffered</span><spanclass="special">*</span><spanclass="identifier">_stream</span><spanclass="special"><></span></code>
templates to treat 0-byte reads and writes as no-ops, to comply with the
documented type requirements for <codeclass="computeroutput"><spanclass="identifier">SyncReadStream</span></code>,
<codeclass="computeroutput"><spanclass="identifier">AsyncReadStream</span></code>, <codeclass="computeroutput"><spanclass="identifier">SyncWriteStream</span></code> and <codeclass="computeroutput"><spanclass="identifier">AsyncWriteStream</span></code>.
</li>
<liclass="listitem">
Changed some instances of the <codeclass="computeroutput"><spanclass="keyword">throw</span></code>
keyword to <codeclass="computeroutput"><spanclass="identifier">boost</span><spanclass="special">::</span><spanclass="identifier">throw_exception</span><spanclass="special">()</span></code>
to allow Asio to be used when exception support is disabled. Note that
the SSL wrappers still require exception support.
</li>
<liclass="listitem">
Made Asio compatible with the OpenSSL 1.0 beta.
</li>
<liclass="listitem">
Eliminated a redundant system call in the Solaris /dev/poll backend.
</li>
<liclass="listitem">
Fixed a bug in resizing of the bucket array in the internal hash maps.
</li>
<liclass="listitem">
Ensured correct propagation of the error code when a synchronous accept
fails.
</li>
<liclass="listitem">
Ensured correct propagation of the error code when a synchronous read or
write on a Windows <codeclass="computeroutput"><spanclass="identifier">HANDLE</span></code>
fails.
</li>
<liclass="listitem">
Fixed failures reported when <codeclass="computeroutput"><spanclass="identifier">_GLIBCXX_DEBUG</span></code>
is defined.
</li>
<liclass="listitem">
Fixed custom memory allocation support for timers.
</li>
<liclass="listitem">
Tidied up various warnings reported by g++.
</li>
<liclass="listitem">
Various documentation improvements, including more obvious hyperlinks to
function overloads, header file information, examples for the handler type
requirements, and adding enum values to the index.
Implement automatic resizing of the bucket array in the internal hash maps.
This is to improve performance for very large numbers of asynchronous operations
and also to reduce memory usage for very small numbers. A new macro <codeclass="computeroutput"><spanclass="special">(</span><spanclass="identifier">BOOST_</span><spanclass="special">)</span><spanclass="identifier">ASIO_HASH_MAP_BUCKETS</span></code>
may be used to tweak the sizes used for the bucket arrays. (N.B. this feature
introduced a bug which was fixed in Asio 1.4.3 / Boost 1.40.)
</li>
<liclass="listitem">
Add performance optimisation for the Windows IOCP backend for when no timers
are used.
</li>
<liclass="listitem">
Prevent locale settings from affecting formatting of TCP and UDP endpoints.
</li>
<liclass="listitem">
Fix a memory leak that occurred when an asynchronous SSL operation's completion
handler threw an exception.
</li>
<liclass="listitem">
Fix the implementation of <codeclass="computeroutput"><spanclass="identifier">io_control</span><spanclass="special">()</span></code> so that it adheres to the documented
type requirements for IoControlCommand.
</li>
<liclass="listitem">
Fix incompatibility between Asio and ncurses.h.
</li>
<liclass="listitem">
On Windows, specifically handle the case when an overlapped <codeclass="computeroutput"><spanclass="identifier">ReadFile</span></code> call fails with <codeclass="computeroutput"><spanclass="identifier">ERROR_MORE_DATA</span></code>. This enables a hack
where a <codeclass="computeroutput"><spanclass="identifier">windows</span><spanclass="special">::</span><spanclass="identifier">stream_handle</span></code> can be used with a message-oriented
named pipe.
</li>
<liclass="listitem">
Fix system call wrappers to always clear the error on success, as POSIX
allows successful system calls to modify errno.
</li>
<liclass="listitem">
Don't include termios.h if <codeclass="computeroutput"><spanclass="special">(</span><spanclass="identifier">BOOST_</span><spanclass="special">)</span><spanclass="identifier">ASIO_DISABLE_SERIAL_PORT</span></code> is defined.
Improved compatibility with some Windows firewall software.
</li>
<liclass="listitem">
Ensured arguments to <codeclass="computeroutput"><spanclass="identifier">windows</span><spanclass="special">::</span><spanclass="identifier">overlapped_ptr</span><spanclass="special">::</span><spanclass="identifier">complete</span><spanclass="special">()</span></code> are correctly passed to the completion
handler.
</li>
<liclass="listitem">
Fixed a link problem and multicast failure on QNX.
</li>
<liclass="listitem">
Fixed a compile error in SSL support on MinGW / g++ 3.4.5.
</li>
<liclass="listitem">
Drop back to using a pipe for notification if eventfd is not available
where the return value indicates the maximum number of bytes to be transferred
on the next read or write operation. (The old CompletionCondition signature
is still supported for backwards compatibility).
</li>
<liclass="listitem">
New <codeclass="computeroutput"><spanclass="identifier">windows</span><spanclass="special">::</span><spanclass="identifier">overlapped_ptr</span></code> class to allow arbitrary
overlapped I/O functions (such as <codeclass="computeroutput"><spanclass="identifier">TransmitFile</span></code>)
to be used with Asio.
</li>
<liclass="listitem">
On recent versions of Linux, an <codeclass="computeroutput"><spanclass="identifier">eventfd</span></code>
descriptor is now used (rather than a pipe) to interrupt a blocked select/epoll
reactor.
</li>
<liclass="listitem">
Added const overloads of <codeclass="computeroutput"><spanclass="identifier">lowest_layer</span><spanclass="special">()</span></code>.
</li>
<liclass="listitem">
Synchronous read, write, accept and connect operations are now thread safe
(meaning that it is now permitted to perform concurrent synchronous operations
Added wrappers for POSIX stream-oriented file descriptors (excluding regular
files).
</li>
<liclass="listitem">
Added wrappers for Windows stream-oriented <codeclass="computeroutput"><spanclass="identifier">HANDLE</span></code>s
such as named pipes (requires <codeclass="computeroutput"><spanclass="identifier">HANDLE</span></code>s
that work with I/O completion ports).
</li>
<liclass="listitem">
Added wrappers for Windows random-access <codeclass="computeroutput"><spanclass="identifier">HANDLE</span></code>s
such as files (requires <codeclass="computeroutput"><spanclass="identifier">HANDLE</span></code>s
that work with I/O completion ports).
</li>
<liclass="listitem">
Added support for reactor-style operations (i.e. they report readiness
but perform no I/O) using a new <codeclass="computeroutput"><spanclass="identifier">null_buffers</span></code>
type.
</li>
<liclass="listitem">
Added an iterator type for bytewise traversal of buffer sequences.
</li>
<liclass="listitem">
Added new <codeclass="computeroutput"><spanclass="identifier">read_until</span><spanclass="special">()</span></code>
and <codeclass="computeroutput"><spanclass="identifier">async_read_until</span><spanclass="special">()</span></code>
overloads that take a user-defined function object for locating message
boundaries.
</li>
<liclass="listitem">
Added an experimental two-lock queue (enabled by defining <codeclass="computeroutput"><spanclass="special">(</span><spanclass="identifier">BOOST_</span><spanclass="special">)</span><spanclass="identifier">ASIO_ENABLE_TWO_LOCK_QUEUE</span></code>)
that may provide better <codeclass="computeroutput"><spanclass="identifier">io_service</span></code>
scalability across many processors.
</li>
<liclass="listitem">
Various fixes, performance improvements, and more complete coverage of
