What does boost::asio::spawn do?
c++,boost,boost-asio,boost-coroutine
In short: When spawn() is invoked, Boost.Asio performs some setup work and then will use a strand to dispatch() an internal handler that creates a coroutine using the user provided function as an entry point. Under certain conditions, the internal handler can be will be invoked within the call to...
How to run Boost.Asio server on port 80?
Run as root. The problem is that you don't have the permission to bind to a privileged port (<1024 on most systems). If you're certain that the child process of Xcode runs as root, find out which process is already listening on port 80 (lsof and netstat)...
How to prevent c++ asio tcp server from shutdown?
It looks like you should probably create some wait condition before accepting new connection if you're "out of ID"s. Because, if you don't, you can simply continue accepting by making acceptor_.async_accept(new_session->socket(), boost::bind(&chat_server::handle_accept, this, new_session, boost::asio::placeholders::error)); unconditional, but you have a loop: you'll be wasting resources accepting connections that you can't...
Boost raw sockets
boost::asio::ip::icmp::socket is a raw socket. The ip::icmp type encapsulates flags and types used for ICMP. In particular, the implementation of ip::icmp::type() returns SOCK_RAW: /// Obtain an identifier for the type of the protocol. int type() const { return BOOST_ASIO_OS_DEF(SOCK_RAW); } As icmp::socket's protocol type is raw, the ICMP example will...
Error while sending encrypted data with Boost::asio::async_send_to
c++,encryption,aes,boost-asio,crypto++
The key here is that the erroneous data begins after the first null (0x00) value in your encrypted data array. The following line: strcpy(newSendBuffer, encSendBuffer.c_str()); ...looks like it's only copying up to the data until that null byte into newSendBuffer. The send function is sending that buffer contents just fine;...
Permission refused when connecting to domain socket created by Boost.Asio
c++,sockets,c++11,boost-asio,socat
The issue is most likely the lifetime of the acceptor. The acceptor is an automatic variable in the DomainListener constructor. When the DomainListener constructor completes, the acceptor is destroyed, causing the acceptor to close and cancel outstanding operations, such as the async_accept operations. Cancelled operations will be provided an error...
C++ lambda, not seeing function and argument?
c++,multithreading,c++11,lambda,boost-asio
In the lambda that is calling callAFunctionHere, the this that is captured is the one for the instance of class A::TimerService, but you are trying to implicitly use members of an class A instance. You need a reference to an object of type A, and use that object's members. class...
Correct syntax to assign unique_ptr to new boost::asio::io_service::work object?
c++,syntax,boost-asio,unique-ptr
Use unique_ptr::reset: keepAlive.reset(new boost::asio::io_service::work(IO_Service)); It's valid to use a unique_ptr for deferred construction, although it would be more ideal to use std/boost optional unless you also explicitly need/want to dynamically allocate it. I'll also note that you should attempt to design your classes so that you can fully construct everything...
Signature for function taking boost::bind as an argument (boost::asio timer callback)?
Indeed the return type of boost::bind is an expression template, and much more complicated than a function type. It is, after all, not a function but a function object (complete with bound attribute values) of an on-the-fly synthesized type. This type is implementation defined and you don't need to know...
boost::asio::io_service::run does not return while having no work
Apparently if you choose to define BOOST_ASIO_ENABLE_HANDLER_TRACKING then you must do so in all boost::asio translation units. I don't see this mentioned in the documentation, but I did find it on the Boost mailing list. When I add add_definitions(-DBOOST_ASIO_ENABLE_HANDLER_TRACKING) to your CMakeLists.txt so it is applied globally then I don't...
Boost async server buffer error
You missed the include #include <boost/array.hpp> The toupper loop is wrong ((&sendBuffer)[i]) = toupper((&receiveBuffer)[i]); should be more like ((*sendBuffer)[i]) = toupper((*receiveBuffer)[i]); or even more like std::transform(receiveBuffer->begin(), receiveBuffer->end(), sendBuffer->begin(), static_cast<int(&)(int)>(std::toupper)); Pro tip: consider using unsigned char in the buffer to avoid unwanted sign extension when passing int to_upper ((*sendBuffer)[i]) =...
Handle websocketpp connection path
c++,c++11,websocket,boost-asio,websocket++
Well, i found soultion by myself :) You should use following code for that purpose: server::connection_ptr con = s.get_con_from_hdl(hdl); std::string path = con->get_resource(); ...
Serializing mutable state and sending it asynchronously over the network with nearly-zero-copy (Cap'n Proto + ZeroMQ)
c++,serialization,boost,boost-asio,zeromq
I do not know much about ZeroMQ's interface but I can give advice on how to minimize copies from Cap'n Proto. On the sending side, use capnp::MessageBuilder::getSegmentsForOutput() (capnp/message.h) to get direct pointers to the message's content without copying. This gives you an array of arrays of bytes (actually, words, but...
C++ URDL Compile Errors with Xcode 6.1 / LLVM 6.0
c++,xcode,boost,clang,boost-asio
Problem Solved ! :) Download the URDL Version from Github instead of the Website think-async.com as I did before.
Boost asio send and receive messages
Since it's apparently safe to assume you just want to send /any/ message by the simplest means possible: Live On Coliru #include <boost/asio.hpp> struct Client { boost::asio::io_service& io_service; boost::asio::ip::tcp::socket socket; Client(boost::asio::io_service& svc, std::string const& host, std::string const& port) : io_service(svc), socket(io_service) { boost::asio::ip::tcp::resolver resolver(io_service); boost::asio::ip::tcp::resolver::iterator endpoint =...
Using the same Boost.Asio io_service for accepting tcp connections synchronously and as a thread pool
That's perfectly fine. A caveat would be if you post tasks that block for non-trivial amounts of time. Async IO operations all imply very short execution times. If you clog the service threads with non-IO tasks, the IO tasks will get high(er) latency...
Boost.Asio, two readings by the same socket
async_read is guaranteed to cause exactly one call of the handler. You must not call async_read again until this handler has been called. question: are you running the io_service in multiple threads? If so, you'll need to pass your handler through an asio::strand. ...
Boost Asio - Client to Server Strange output
Well, I did it. When I read something, the data length was in the variable size_t length. So, from it, I did : if (!error) // If there is no error { for (int i = 0; i < (length); i++) // If i < length { std::cout << m_data[i];...
Why does read() fail with EAGAIN when piping to a program using boost::asio for STDIN/STDOUT?
The way that most shells and terminals work is that stdin and stdout are read/write file descriptors for the same file. Consider the following: $ echo FOO >&0 FOO Congratulations, you've just written something to stdin's file descriptor. The other half of the file can be found in the fcntl(2)...
boost::asio how to read full buffer in right way?
From the read_some reference: This function is used to read data from the stream socket. The function call will block until one or more bytes of data has been read successfully, or until an error occurs. With remarks: The read_some operation may not read all of the requested number of...
Concurrent read and async_read_some in boost asio
Boost.Asio does not make this guarantee on any I/O object. When a synchronous operation is initiated on an I/O object that has an outstanding asynchronous operation of the same type, the order in which the underlying system calls occur is unspecified.
Boost Exception Handling with Boost ASIO
The explanation you quote is somewhat misleading. Actually, io_service propagates any exceptions that escape from completion handlers, so it doesn't matter whether we use it for "user work" or for "asio functions" - in any case we might want to handle exceptions escaping from io_service::run (not only std::exception!). Consider the...
How to get part of a std::string into a streambuf without copying?
c++,boost,boost-asio,stdstring,streambuf
istream::operator>>() mangles the contents of my streambufs (as you would expect given that it's 'formatted'). Open your input stream with std::ios::binary flag and manipulate it with is >> std::noskipws For example, if I want to get a substring of a string into a streambuf, how do I do that...
How to catch strange undefined behaviour in C++ code?
c++,debugging,boost,gdb,boost-asio
On ubuntu, I like to run with valgrind (http://valgrind.org/). sudo apt-get install valgrind valgrind ./mypgrogram It doesn't report all issues, but when it does, it will report the nature and origin. Also recommended: valgrind --db-attach=yes ./myprogram Which allows you to debug (backtrace, inspect) and continue the program when a violation/uninitialized...
C++ , return string from function; boost::asio read / write
The most generic way would be use a asio::streambuf streambuf sb; size_t transferred = read (port, sb, ec); According to the docs: This function is used to read a certain number of bytes of data from a stream. The call will block until one of the following conditions is...
How to connect signal to boost::asio::io_service when posting work on different thread?
c++,multithreading,boost,boost-asio,signals-slots
In light of new information, the problem is with your boost::bind. You are trying to call a member function without an object to call it on: you are trying to call ProcessData but you haven't told the bind on which object you wish to call it on. You need to...
Boost http server example not working?
c++,http,boost,boost-asio,server
If you are getting an HTTP response with status code of 404, then the HTTP server is running, handling the request, and serving a response. If the server was not running, then an HTTP response would not be returned. The browser may provide additional details about the failure: $ lsof...
boost::asio::socket keep alive set_option exception [duplicate]
You need to open the socket before you can use it. Before you call open the actual underlying socket descriptor is not created. Alternatively use a constructor that both create the object and opens the socket....
Can't use asio::placeholders::error in non-Boost version of Asio
In short, use std::placeholders::_1 instead of asio::placeholders:error. Asio only supports the convenient placeholder variables when using Boost.Bind. The error placeholder documentation states: An argument placeholder, for use with boost::bind(), ... When using std::bind() to create handlers, one needs to use std::bind's placeholders. The async_accept() operation accepts a handler that meets...
How to know which version of openssl boost ssl is using
Boost will use the openssl version provided by your system (or explicitly specified during compilation/linkage, check your build script) It depends on your linkage type, if you link statically against OpenSSL, you will need to recompile. If you are linking dynamically, then updating the DLL/shared object will be enough...
Passing a unique_ptr reference to boost::bind?
c++,gcc,boost,boost-asio,boost-bind
You'd need C++-14 and generalized lambda capture to make this work -- you'd need to move the unique pointer into the lambda. Instead, just use a shared_ptr, which std::bind understands natively: std::shared_ptr<manager> m; m = std::make_shared<manager>(); io.post(std::bind(&manager::run, std::move(m))); The std::move is optional but ensures that m doesn't keep the manager...
Resuming asio coroutine from another thread
A coroutine runs within the context of a strand. In spawn(), if one is not explicitly provided, a new strand will be created for the coroutine. By explicitly providing strand to spawn(), one can post work into the strand that will be synchronized with the coroutine. Also, as noted by...
Move constructor is not called with boost::asio::ip::tcp::socket
c++,c++11,boost,boost-asio,move-constructor
This is a known bug with the compiler. The bug ticket mentions that this has been fixed in VS 2015 RTM. As a workaround, consider creating a shim to move the socket. Here is a small example demonstrating this approach: #include <memory> #include <thread> #include <boost/asio.hpp> void Func(boost::asio::ip::tcp::socket) {} int...
What means blocking for boost::asio::write?
In short, boost::asio::write() blocks until all data has been written to the stream; it does not block until all data has been transmitted. To wait until data has been transmitted, consider using tcdrain(). Each serial port has both a receive and transmit buffer within kernel space. This allows the kernel...
How should I pass a boost::asio::yield_context in my own functions?
c++,c++11,boost,boost-asio,coroutine
It makes a lot of sense that the context has a lifetime that corresponds to that of the coroutine itself. This means, I anticipate it containing a pointer (or reference_wrapper) to the actual (hidden) implementation state. That said, simply do as the Boost library itself does, which is to take...
boost asio custom allocator handler io service post compile errors
c++,templates,boost,bind,boost-asio
To be compatible with CompletionHandler object returned by makeCustomAllocHandler should define void operator()() instead of void operator()(const boost::system::error_code&, std::size_t) required by ReadHandler and used in server example.
win7 boost::asio::windows::stream_handle constructor throws error
You might use GetStdHandle, so: HANDLE isfhandle = GetStdHandle(STD_INPUT_HANDLE); However, I don't think consoles support asynchronous IO in windows: The handle must be to an object that supports overlapped I/O. If a handle is provided, it has to have been opened for overlapped I/O completion. For example, you must specify...
How to deal with extra characters read into ASIO streambuf?
While the read_until() operations commit all data read into the streambuf's input sequence, they return a bytes_transferred value containing the number of bytes up to and including the first delimiter. In essence, it provides the size of the frame, and one can limit istream to only read a portion of...
ASIO handler arguments and boost::bind, compile time error
The error code cannot be taken by reference. Make it by-value or by const&: void on_data_recv(boost::system::error_code/* ec */, size_t /*bytes_transferred*/) { Also, consider using the Asio specific placeholders: socket.async_read_some(boost::asio::buffer(recv_buffer), boost::bind(&RPC::on_data_recv, this, boost::asio::placeholders::error, boost::asio::placeholders::bytes_transferred)); Also use proper lock guards. We're in C++! It's easy to make things exception-safe, so why not?...
Getting started with network programming in Qt [closed]
c++,qt,network-programming,boost-asio
Trying to answer your first question, it depends on which platforms are you targeting (Windows, Linux, OSX...). You could use native OS socket api (bsd sockets or winsock) but Qt provides very good abstractions for these so for the sake of simplicity I would stick with it. I'm unfamiliar with...
boost async operations not working (for me)
c++,asynchronous,boost,boost-asio
The problem is that the deadline_timer object needs to stay alive until the handler triggers, otherwise the handler will be triggered instantly with an error when is.run() is called. The timer is being destroyed when the async_rotateLeftFor function exits. What I do to keep the timer around, is wrap the...
Boost async sockets and thread pool on same io_service object
c++,multithreading,sockets,boost,boost-asio
Neither. Each async_read operation is initially handled by the thread that called it. If forward progress can't be made without the socket being ready (because the other side needs to send or receive something), the async operation returns to the calling thread. Socket readiness is monitored by the "reactor", an...
asio socket, inside a class declaration, scope issue
You've declared socketTCP as a local variable in the constructor, not a member variable of the class. That means you can't use it in other functions. Presumably you meant to declare a member variable, and initialize that in the constructor instead of a local variable....
boost::asio sync server is not accepting connections after first one
The general pattern for an asio-based listener is: // This only happens once! create an asio_service create a socket into which a new connection will be accepted call asio_service->async_accept passing the accept socket and a handler (function object) [ see below] start new threads (if desired. you can use the...
Calculating the sum of a large vector in parallel
c++,multithreading,algorithm,parallel-processing,boost-asio
Is Boost.Asio suitable for this problem? The main purpose of Boost.Asio is to provide an asynchronous model for network and I/O programming, and the problem you describe does not seem to have much to do with networking and I/O. I think that the simplest solution is to use the threading...
Boost.Asio TCP moved-to socket destructor not enough to cleanly close?
The code only creates a single socket, which is an automatic variable whose lifetime will end once main() returns. std::move(socket) only returns an xvalue that can be provided to socket's move constructor; it does not construct a socket. To resolve this, consider changing the callback() signature to accepting the socket...
Does BOOST asio supports eventfd? like epoll
The documentation describes some, but not all, of the things the io_service class can do. Note the that it says "including", not "only". Also, the next sentence in the documentation reads: The io_service class also includes facilities intended for developers of custom asynchronous services. If you are reading or writing...
How to restart boost deadline timer
The first problem is that the handler will still be called if there is an error (such as it being cancelled), you need to check the error code. void print(const boost::system::error_code& e ) { if( e ) return; // we were cancelled // actual error code for cancelled is boost::asio::error::operation_aborted...
Multiple Http Servers with Poco and Boost C++
c++,boost-asio,poco,poco-libraries
HttpServerApplication is not designed to be used in this way. It's designed to be a singleton. http://pocoproject.org/docs/Poco.Util.ServerApplication.html You can fix that part by not deriving from ServerApplication in your HttpServer class. After all, you want multiple servers, not applications. In my simplest test, the following works: #include <Poco/Net/HTMLForm.h> #include <Poco/Net/HTTPRequestHandler.h>...
dispatch response packet according to packet sequence id
You could use std::promise and std::future (or their boost counterparts if your are not yet on C++11). The idea is to store a std::shared_ptr<std::promise<bool>> with the current sequence id as a key in the map whenever a request is sent. In the blocking send function you wait for the corresponding...
Boost asio ssl: password callback not called if private key passed with context::use_private_key
This reflects a limitation of the underlying OpenSSL API: Encyption applies to loading keys from file only: The private keys loaded from file can be encrypted. In order to successfully load encrypted keys, a function returning the passphrase must have been supplied, see ssl_ctx_set_default_passwd_cb(3). (Certificate files might be encrypted as...
boost::asio::serial_port and RTS pin
c++,boost,serial-port,boost-asio
I ended up using the windows api (OS specific) approach to solve my problem. #include <iostream> #include <cstdlib> #include <string> #include <windows.h> namespace comm{ class rs232 { const HANDLE commDevice; const DWORD clear_RTS = 4; const DWORD set_RTS = 3; public: rs232( HANDLE commDeviceIn ): commDevice(commDeviceIn) {} rs232( std::string commName...
How to use boost::asio with Linux GPIOs
As far as I know, it is not possible to get this particular behavior with Boost.Asio. While the kernel flags some files on the procfs and sysfs as pollable, they do not provide the stream-like behavior that is expected from boost::asio::posix::stream_descriptor and its operations. Boost.Asio's epoll reactor is edge-triggered (see...
boost::asio read n bytes from socket to streambuf
c++,boost,boost-asio,boost-serialization,streambuf
There are overloads for both boost::asio::read() and boost::asio::async_read() that accept instances of boost::asio::basic_streambuf as its buffer: read(SyncReadStream&, basic_streambuf&); read(SyncReadStream&, basic_streambuf&, CompletionCondition); read(SyncReadStream&, basic_streambuf&, boost::system::error_code&); read(SyncReadStream&, basic_streambuf&, CompletionCondition, boost::system::error_code&); async_read(AsyncReadStream&, basic_streambuf&, ReadHandler);...
boost::iostream readline stop after 4096 bytes
I'm not reproducing this with Ubuntu linux 14.10 64 bit gcc 4.8.2 boost_1_57 localhost traffic Did you check there are no linefeeds in the input? If I feed it a continues stream of input, I do not detect such issues. E.g. with netcat, Live On Coliru for a in {1..1024};...
boost asio post not working , io_service::run exits right after post
You don't actually post any work to the service. You start a thread that may eventually post work, but the main thread has already exited by that time. Either, run the ioservice on the thread or make sure it has io_service::work Here's a fix with a dedicated service thread and...
boost asio TCP server must bind to an IP address?
Bind to 0.0.0.0. That's the "wildcard" that listens on all interfaces for any incoming connection. If you bind to 127.0.0.1, your server will only accept incoming connections over the loopback, which won't let you client connect (since your client isn't using the loopback)....
C2228: Error with TCP asio server
Where is socket defined? sounds like it isn't properly defined causing the write and read_until functions to throw the error. read_some and write_some are called inside the write and read_until (edit) looking at your code, unless socket is a global vairable, how is it getting passed into your session function,...
boost::asio::async_read() of stream_descriptor now returning EOF
Ubuntu 15.04 contains the 3.19 kernel, which has a reported regression in the TUN/TAP user API: With kernel 3.19, a read() from a TUN/TAP file descriptor in non-blocking mode will return 0 when no data is available, rather than fail with EAGAIN. Per the documentation, the return value from read()...
Obtaining the sig_int value from siginfo in boost::siginfo handler
In short, no. In the presence of sigaction(), Boost.Asio registers its internal signal handler as sa_handler and does not set the SA_SIGINFO flag. Hence, Boost.Asio's signal handler never receives the siginfo_t associated with the signal, and cannot propagate it to the user's SignalHandler when completing the async_wait() operation. Here is...
Boost Asio, async UDP client - crash on shutdown
The destruction of AsyncUDPClient does not properly synchronize with the thread(s) running the io_service. This can result in undefined behavior being invoked when a thread processing the io_service attempts to interact with the AsyncUDPClient and its io_service after their lifetime has ended. To resolve this, do not detach from the...
Intermittent issues with SSL, using Boost/Asio
c++,multithreading,ssl,openssl,boost-asio
This issue was caused by bug in the Asio SSL implementation. Reported it to the Asio Github issue tracker. When an error occur in OpenSSL, errors-codes are pushed onto a queue. A single call to OpenSSL may result in multiple error-codes being pushed to the queue. For example, a low-level...
How should I find which client I am receiving from in Boost Asio in UDP?
The application code is responsible for demultiplexing. At a high-level, there are two options: Use a single endpoint to conceptually function as an acceptor. Upon receiving a handshake message, the client would instantiate a new local endpoint, and inform the client to use the newly constructed endpoint for the remainder...
issues about using async_write right after async_read_until
The async_write() overload being used is considered complete when all of the streambuf's data, its input sequence, has been written to the WriteStream (socket). It is equivalent to calling: boost::asio::async_write(stream, streambuf, boost::asio::transfer_all(), handler); One can limit the amount of bytes written and consumed from the streambuf object by calling this...
cancel a deadline_timer, callback triggered anyway
c++,c++11,boost,callback,boost-asio
First, let's show the problem reproduced: Live On Coliru (code below) As you can see I run it as ./a.out | grep -C5 false This filters the output for records that print from C1's completion handler when really c1_active is false (and the completion handler wasn't expected to run) The...
Stopping async_connect
There's nothing elementary wrong with the code, and it does exactly what you desire on my Linux box: TCP Connection in progress Connection not established... Trying to close socket... TCP Connection failed real 0m3.003s user 0m0.002s sys 0m0.000s Notes: You may have success adding a cancel() call to the stop()...
send the full contents of a ring buffer on subscription and then send new data
You should just do what you intend to. You absolutely don't need a streambuf to use with Boost Asio: http://www.boost.org/doc/libs/release/doc/html/boost_asio/reference/buffer.html If the problem is how to avoid having the producer "wait" until all consumers (read: connections) are done transmitting the data, you can always use ye olde trick of alternating...
Create timer with boost::asio
Update I get it. You want dynamically allocated timers? Live On Coliru #include <boost/asio.hpp> #include <boost/make_shared.hpp> using namespace boost; using Timer = shared_ptr<asio::deadline_timer>; asio::io_service _io; void handler(int a, const system::error_code& = {}, Timer timer = make_shared<Timer::element_type>(_io)) { std::cout << "hello world\n"; timer->expires_from_now(posix_time::seconds(1)); timer->async_wait(bind(handler, a, asio::placeholders::error, timer)); } int main() {...
Getting the IP address of a received message in boost
You can do so using the boost::asio::ip::udp::socket::async_receive_from() or boost::asio::ip::udp::socket::receive_from() functions, which have the endpoint_type & sender_endpoint output parameter. The returned endpoint can be used to resolve the sender IP address. ...
Why does boost::asio::io_service not compile with std::bind?
The error message indicate that std::bind() cannot determine which io_service::run() overload to use: std::size io_service::run(); std::size io_service::run(boost::system::error_code&); For this particular case, Boost.Bind does not have an issue, but it does provide some troubleshooting for binding an overloaded functions. It recommends either casting: std::bind( static_cast<std:size_t (boost::asio::io_service::*)()>(&boost::asio::io_service::run), &ioService); Or using a temporary...
ConnectNamedPipe and asio overlappped ptr
c++,windows,boost-asio,named-pipes
Found the issue. I've not associated pipe with IOCP itself in server part. It can be done by wrapping pipe native handle returned by CreateNamedPipeA into boost::asio::windows::stream_handle just before calling ConnectNamedPipe. typedef boost::asio::windows::stream_handle StreamHandler; std::shared_ptr<StreamHandler> streamHandler = std::make_shared<StreamHandler>(*mIoService); streamHandle->assign(pipe); ...
asio :how does server actively send information to client while listening to client at the same time?
I hope I got your question correctly and you also want to understand how asio works with async operations. In brief, everything happens in run function of io_service object. When you call async_write or async_read in some function, you register a callback (that will be called when some event happens)...
Boost Asio Error
c++,boost,windows-7,boost-asio
I'm going to assume from the symptoms that you run on Windows. On windows, static_mutex is implemented as a named (interprocess) mutex and gets "opened" using CreateMutexW: If the mutex is a named mutex and the object existed before this function call, the return value is a handle to the...
iostream and No_delay option
Where you set the option, the stream is still invalid (not open). Wait until the socket is open, before setting the option: Live On Coliru #include <boost/asio.hpp> #include <iostream> static boost::asio::ip::tcp::no_delay const no_delay_option (true); int main() { using boost::asio::ip::tcp; tcp::iostream socketStream; boost::asio::io_service io_service; tcp::endpoint endpoint (tcp::v4(), 6666); tcp::acceptor acceptor (io_service,...
SSL certificates and Boost asio
Most OpenSSL installations will install trusted certificates as part of the installation process, and boost::asio::ssl::context::set_default_verify_paths() is fairly good at finding the correct paths. The certification verification is failing because the the client is attempting to verify the peer's certificates with hostname verification (rfc2818), and is checking for the literal "host.name"...
Cancelling callbacks in Boost ASIO
multithreading,sockets,c++11,boost,boost-asio
The program is invoking undefined behavior when the server thread attempts to unlock the read_lock that it does not own. int main() { ... std::mutex read_mutex; std::unique_lock<std::mutex> read_lock(read_mutex); // Acquired by main. std::condition_variable read_done; std::thread server([&]() { // Capture lock reference. std::unique_lock<std::mutex> lock(mutex); ... // The next line invokes undefined...
Clarification on the use of `boost::bind` and `this`
boost::asio::placeholders::error is just like using boost::placeholders::_1 with boost::bind, and when you pass a bind expression containing that to an asio completion handler function, the function will invoke your handler with the boost::system::error_code result from the operation it performed, thus allowing your handler access to the error code. In your second...
Setting option SO_SETFIB on boost sockets
You would use the boost::asio::detail::socket_option::integer socket option helper template: typedef boost::asio::detail::socket_option::integer<SOL_SOCKET, SO_SETFIB> set_fib; // ... sock.set_option(set_fib(42)); ...
assigning io_service to work - boost::asio
Assuming you mean boost::asio::io_service::work work(io_service); because boost::asio::io_service is not copyable, you can do that in the constructor init list like normal: Foo::Foo(boost::asio::io_service &io_service) : work_member(io_service) { // stuff } ...
Boost::ASIO multithreaded writing stale data to socket?
multithreading,sockets,boost,tcp,boost-asio
Okay, Sam Miller gets the credit for the answer here, but he posted it as a comment so I'm answering to close the question now that I have it figured out. Ultimately, the bug was most likely an issue with interleaved write calls and accessing the object's data. I've re-written...
boost.asio: Accept IPv4 and IPv6 together
c++,networking,boost,boost-asio
If you create a IPv6 acceptor, it will accept both IPv4 and IPv6 connections if IPV6_V6ONLY socket option is cleared. IPv4 addresses will be presented as IPv6 addresses, in the IPv4-mapped format. Problems arise mainly around whether IPV6_V6ONLY is available or what the default value is (turned on or off)....
Error while using Boost Asio
c++,boost,mingw,boost-asio,codeblocks
So, I fixed this error by adding "-D_WIN32_WINNT=0x0501 -DWINVER=0x0501" to both compilers linker options (in C::B) and #defines. Guess I added _WIN32_WINNT somehow wrong.
Boost::asio asynchronous connection timeout setting
Since you are receiving data, you may want to set: SO_RCVTIMEO instead of SO_SNDTIMEO Although mixing boost and system calls may not produce the expected results. For reference: SO_RCVTIMEO Sets the timeout value that specifies the maximum amount of time an input function waits until it completes. It accepts a...
Does boost asio io_service guarantee execution of two parallel call chains?
The io_service currently makes no guarantees about the invocation order of handlers. Thus, the io_service could choose to invoke only a single call chain. Currently, only a strand specifies guarantees. With that said, I would not worry too much about the io_service currently not making the guarantee. As Asio is...
How to save JSON response of HTTP GET in a .json file in C++?
Well, actually this was a cake walk. I apologise to waste your time. To get just the JSON string output in the file I did the following. // Writing the remaining data to output. freopen("JSONoutput.json","w",stdout); std::cout << s.rdbuf() << "\n" << std::endl; freopen() : Reuses stream to either open the...
Who is failing, boost, clang, or gcc? Issue with std::chrono used with boost::asio
The chrono documentation describes this Support for the std::chrono facilities is automatically enabled for g++ 4.6 and later, when the -std=c++0x or -std=gnu++0x compiler options are used. (Note that, for g++, the draft-standard monotonic_clock is used in place of steady_clock.) Support may be disabled by defining BOOST_ASIO_DISABLE_STD_CHRONO, or explicitly enabled...
Executing asynchronous operations within the same strand
c++,multithreading,sockets,asynchronous,boost-asio
If access to the stream object is controlled by a mutex, making sure that only one thread operates on the ssl stream at a given time, what is the need for using an implicit/explicit strand? There is no need then. The mutex makes the operations serialize as on a...
Boost asio for multiple asynchronous network client operations
Here's a rough outline of what you need to do: First note that io_service.run() will return immediately if it has no work to do. So depending on your workflow you may need to defer calling it until you actually have the first asynchronous connect queued up. If you look at...
set_option: Invalid argument when setting option boost::asio::ip::multicast::join_group inside lambda
c++11,boost,boost-asio,multicast
There is a race condition that can result in dangling references being accessed, invoking undefined behavior. The lambda capture-list is capturing the automatic variables, multicast_address and portNumber, by reference. However, the lifetime of these objects may end before their usage within _io_service_thread: void doIO() { const boost::asio::ip::address multicast_address = /*...
Read message in its entirety with Boost.ASIO [WebSocket]
c++,boost,websocket,boost-asio
Looking at the websocket spec here: http://datatracker.ietf.org/doc/rfc6455/?include_text=1 you are on the right track. Use async_read_until to handle the handshake as it has undefined length but is delimited the same as http, and then, personally for exchange of the actual data after completing the handshake, switch to using async_read using either,...
Boost: Re-using/clearing text_iarchive for de-serializing data from Asio:receive()
c++,serialization,boost,deserialization,boost-asio
No there is not such a way. The comparison to MemoryStream is broken though, because the archive is a layer above the stream. You can re-use the stream. So if you do the exact parallel of a MemoryStream, e.g. boost::iostreams::array_sink and/or boost::iostreams::array_source on a fixed buffer, you can easily reuse...
variadic boost bind type resolution
c++,templates,bind,boost-asio,variadic-templates
My suggestion for the function you ask about: template <typename T, typename... Args> void enqueue(T &t, Args const&... args) { this->io_service->post([=]{ auto s = stringer(t, args...); //std::fprintf(stderr, "%s\n", s.c_str()); }); } This works with GCC and Clang (GCC 4.9 or later because of a known issue with captured variadic packs)....
Using Boost in a DLL project (ActiveX)
c++,boost,dll,visual-studio-2013,boost-asio
The short answer is to do something like this: C:\local\boost_1_58_0>bjam.exe runtime-link=static and remove BOOST_ALL_NO_LIB is its set, then build the DLL again. That should fix that....
boost::asio read from /dev/input/event0
c++,boost,debian,boost-asio,keypad
On my system, event2 represents the mouse, and the following simple readloop program works like a charm. Run as root: #include <boost/asio.hpp> #include <boost/asio/posix/stream_descriptor.hpp> #include <boost/bind.hpp> #include <iostream> // for debug output #include <iomanip> #include <linux/input.h> // for input_event #include <boost/range/adaptor/sliced.hpp> #include <boost/date_time/posix_time/posix_time.hpp> using namespace boost::asio; struct input { using...
boost::asio read/write trouble
You get the end of file condition because the remote end of the connection closed or dropped the connection. You should be handling the system errors, or using the overloads that take a reference to boost::system::error_code. How else would you ever terminate the infinite loop? Live On Coliru #include <boost/asio.hpp>...
Where can I download a ca.pem file for boost::asio::ssl?
You can use Mozilla certificate pack converted to PEM format by the authors of cURL library. You can download it from cURL site. I tried to run this boost.asio example using this pack and it ran successfully....
Avoid socket inheritance when starting Linux service from C++ application
c++,linux,sockets,boost,boost-asio
If you're referring to the socket descriptors themselves being inherited by exec'd child processes, and this being undesirable, then you could pass SOCK_CLOEXEC when creating the sockets with socket(2) to make sure that they are closed when you execute other programs. (This won't close the connection by the way, since...
Boost::Asio - read or read_until?
One is not better than the other. You use what your protocol requires. Typically binary protocols specify the packet length up front (by sending it first) text protocols tend to structure information using delimiters (like { ... } for JSON like grammars, or \r\n for SMTP/HTTP etc). Naturally you'd use...
What is the impact of calling io_service::run method twice
Your assumptions are correct. Each thread which calls io_service::run() will dequeue and execute handlers (simple function objects) in parallel. This of course only makes sense if you have more than one source of events feeding the io_service (such as two sockets, a socket and a timer, several simultaneous post() calls...