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async_read_some
by Christer Borgqvist 01 May '12

01 May '12

Hi, Im playing around with the /boost_asio/example/http/server3 and using POST method. The bytes_transferred is 231, but thats only the header and ends with \r\n\r\n, need to read the rest. Sometimes i get bytes_transferred to 1032, the right amount of data, sometimes i get bytes_transferred = 231, but if i print the buffer_ i have all the 1032 bytes. Is it right that the bytes in the buffer_ and the bytes_transferred is not the same? appreciate any help. /christer void connection::handle_read(const boost::system::error_code& e, std::size_t bytes_transferred) { if (!e) { boost::tribool result; boost::tie(result, boost::tuples::ignore) = request_parser_.parse( request_, buffer_.data(), buffer_.data() + bytes_transferred); if (result) { request_handler_.handle_request(request_, reply_); boost::asio::async_write(socket_, reply_.to_buffers(), strand_.wrap( boost::bind(&connection::handle_write, shared_from_this(), boost::asio::placeholders::error))); } else if (!result) { reply_ = reply::stock_reply(reply::bad_request); boost::asio::async_write(socket_, reply_.to_buffers(), strand_.wrap( boost::bind(&connection::handle_write, shared_from_this(), boost::asio::placeholders::error))); } else { socket_.async_read_some(boost::asio::buffer(buffer_), strand_.wrap( boost::bind(&connection::handle_read, shared_from_this(), boost::asio::placeholders::error, boost::asio::placeholders::bytes_transferred))); } }

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Use boost::shared_ptr with boost::adaptors
by tolik levchik 01 May '12

01 May '12

The following code gives me segfault. But if `foo_ptr` is `foo*` it works fine. #include <vector> #include <boost/range/adaptor/indirected.hpp> #include <boost/range/adaptor/transformed.hpp> #include <boost/range/algorithm/for_each.hpp> #include <boost/bind.hpp> #include <boost/shared_ptr.hpp> struct foo{ foo(int _i): i(_i){} virtual void bar() const{ std::cout << "foo::bar::i " << i << std::endl; } int i; }; typedef boost::shared_ptr<foo> foo_ptr; //typedef foo* foo_ptr; foo_ptr trasform(int i){ return foo_ptr(new foo(i)); } int main(){ std::vector<int> vec; vec.push_back(1); using namespace boost::adaptors; using boost::bind; boost::for_each(vec | transformed(bind(&trasform, _1)) | indirected, bind(&foo::bar, _1)); } Is it expected behavior of adaptors ?

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Making my UdpConnection class thread safe
by Chris Dunphy 30 Apr '12

30 Apr '12

I have implemented some connection classes, using Boost ASIO, to replace some low level C code in an application, and everything is working great, except for one problem. Basically, I have a UdpConnection class that does synchronous read and write, but it uses async methods to handle time-outs as per the boost examples. The problem is I can't figure out how to make it threadsafe. I have tried adding strands to the event handlers to make this class threadsafe (code below), but that isn't working. I suspect it is because of the way timeout is implemented. I have included my code in 4 classes in pastebin. Single threaded is working fine. I also have TcpConnection and UnixSocketConnection classes that don't need to be shared amongst multiple threads and they work fine. However, I can't get multi-threaded UDP code to work. Am I missing something? Sources below: * Connection.h && AsioConnection.h http://pastebin.com/Cbbw37gL * UdpConnection.h && UdpConnection.cpp http://pastebin.com/VLnHBnPs

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[Boost.Optional] Compilation error with boost::optional in Boost 1.49 and GCC 4.4.6
by Jonathan Jones 30 Apr '12

30 Apr '12

Hello, The following code fails to compile when using GCC 4.4.6 and boost::optional from Boost 1.49: #include <boost/optional/optional.hpp> #include <boost/type_traits/is_convertible.hpp> struct grill { template<typename U> grill (U) {} }; template<typename T> struct bar { template<typename U> bar (U, typename boost::is_convertible<U,T>::type* = 0) {} }; void foo() { typedef bar<grill> data_type; boost::optional<data_type> opt; boost::optional<data_type> opt2(opt); // this line (void)opt2; } Here are the error messages (I apologize for the long lines, I shortened them as much as possible by truncating the header paths): type_traits/is_convertible.hpp: In instantiation of ‘const bool boost::detail::is_convertible_basic_impl<boost::optional_detail::optional_base<bar<grill> >&, grill>::value’: type_traits/is_convertible.hpp:329: instantiated from ‘const bool boost::detail::is_convertible_impl<boost::optional_detail::optional_base<bar<grill> >, grill>::value’ type_traits/is_convertible.hpp:452: instantiated from ‘boost::is_convertible<boost::optional_detail::optional_base<bar<grill> >, grill>’ optional/optional.hpp:604: instantiated from ‘boost::optional<T>::optional(const boost::optional<T>&) [with T = bar<grill>]’ optional.cpp:25: instantiated from here optional/optional.hpp:285: error: ‘boost::optional_detail::optional_base<T>::optional_base(const boost::optional_detail::optional_base<T>&) [with T = bar<grill>]’ is protected type_traits/is_convertible.hpp:170: error: within this context type_traits/is_convertible.hpp:170: error: initializing argument 1 of ‘grill::grill(U) [with U = boost::optional_detail::optional_base<bar<grill> >]’ optional/optional.hpp:308: error: ‘boost::optional_detail::optional_base<T>::~optional_base() [with T = bar<grill>]’ is protected type_traits/is_convertible.hpp:170: error: within this context This reproduction case is distilled from a real world example (not my code) where bar=boost::fusion::vector1 and grill=boost::function<void()> The code compiles fine using the same compiler and Boost 1.44. Any ideas on the root of the problem? Thanks in advance! Jon

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Re: [Boost-users] [CMake] link error in Visual Studio when using boost from CMake
by Alain Leblanc 30 Apr '12

30 Apr '12

Don't have much experience with boost in combination with cmake, but don't you still need to add the boost libraries in a target_link_libraries() command? (Or whatever command is usedbto indicate the libraries to link with). A On Apr 30, 2012 2:49 PM, "Hui Wang" <huiwang8921(a)gmail.com> wrote: > Hello, > > I'm using CMake generated Visual Studio solution, and I added boost with > find_package(Boost), > before that I used commands: set(Boost_USE_STATIC_LIBS > ON) set(Boost_USE_MULTITHREADED ON) set(Boost_USE_STATIC_RUNTIME OFF) > after that I used > commands: include_directories(${Boost_INCLUDE_DIR}) add_executable( > MyProject src/main.cpp) > > Because automatic linking is used on Visual Studio when including Boost, > and it typically use static libraries, I try not to conflict with that. But > I get the error: > LINK : fatal error LNK1104: cannot open file > 'libboost_thread-vc100-mt-gd-1_47.lib' > > I installed pre-compiled binary Boost with the installer provided by > BoostPro Computing, and I checked to find that I do have > libboost_thread-vc100-mt-gd-1_47.lib, libboost_thread-vc100-mt-s-1_47.lib > libboost_thread-vc100-mt-sgd-1_47.lib libboost_thread-vc100-mt-1_47.lib > in C:\Program Files\boost\boost_1_47\lib > > I also output messages to find that > Boost_FOUND=TRUE Boost_LIBRARY_DIRS=C:/Program > Files/boost/boost_1_47/lib Boost_INCLUDE_DIRS=C:/Program > Files/boost/boost_1_47 > > So I'm confused why it has the link error. I tried with dynamically > linking too, it can't find the .dll files at runtime either, but again they > exist right there in the directory I installed boost. Could anyone help me > understand where the problem is? > > Thanks! > -- > Sophie Wang > www.sophiehuiwang.com > > > -- > > Powered by www.kitware.com > > Visit other Kitware open-source projects at > http://www.kitware.com/opensource/opensource.html > > Please keep messages on-topic and check the CMake FAQ at: > http://www.cmake.org/Wiki/CMake_FAQ > > Follow this link to subscribe/unsubscribe: > http://www.cmake.org/mailman/listinfo/cmake >

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catch serial port events
by jellad tarek 30 Apr '12

30 Apr '12

hello can i detect a change in pin cts of com1 (in real time) and callback a function with to boost library???? thank you

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get local time in microsecondes :-)
by jellad tarek 30 Apr '12

30 Apr '12

hello i want to get the local time in microseconds (no the diff between 2 times)... like wireshark or commview. in this format 15:23:10,251485 is it possible with the booooost library ?????? 1000 thanks

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filesystem: 'copy' is not a member of boost::filesystem
by Matan Nassau 30 Apr '12

30 Apr '12

Good afternoon, Calling boost::filesystem::copy(), I get the the compiler error 'copy' is not a member of 'boost::filesystem' When I look in boost/filesystem/v3/operations.hpp I see namespace filesystem { … using filesystem3::character_file; // using filesystem3::copy; using copy_file; … } Why is "using filesystem3::copy" line commented out? Matan

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managed_shared_memory memory leak(?)
by Michael Herrmann 29 Apr '12

29 Apr '12

Hello everyone, the following trivial example highlights a memory leak according to MSVC 2010. Does anybody know why this is and how it can be avoided? // The following three directives are required for MSVC's automatic memory // leak detection. #define _CRTDBG_MAP_ALLOC #include <stdlib.h> #include <crtdbg.h> #include <boost/interprocess/managed_shared_memory.hpp> int main(int argc, char *argv[]) { { using namespace boost::interprocess; static const char* shMemIdentifier = "MySharedMemory"; struct ShMemCleaner { ShMemCleaner() { shared_memory_object::remove(shMemIdentifier); } ~ShMemCleaner() {shared_memory_object::remove(shMemIdentifier); } } cleaner; // Create a new segment with given name and size managed_shared_memory segment(create_only, shMemIdentifier, 1024); int* intInShMem = segment.construct<int>("myInt")(2); segment.destroy<int>("myInt"); } _CrtDumpMemoryLeaks(); } Thank you very much! Best, Michael

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C++ Now! Conference Program Highlights C++11
by Jon Kalb 29 Apr '12

29 Apr '12

C++ Now! (formerly BoostCon) is pleased to announce its 2012 program with 35+ inspiring C++ practitioners delivering more than fifty technical sessions. In honor of the release of the new C++11 standard, this May's conference will, for the first time, be offered in three tracks. In addition to the sessions that attendees have come to expecton topics like library design and usage, programming techniques, best practices, academic research, development tools, concurrency, reliability, and performancethis year's program includes a full track devoted to C++11 <http://cppnow.org/locations/c11/> and three keynotes by industry luminaries <http://cppnow.org/overview/> . For those eager to get on board with the new standard, the C++11 content features fifteen hours of tutorial material covering the most important new features and APIs, presented, in many cases, by the language designers themselves. C++ Now! is offering the most complete C++11 tutorial coverage of any conference this year! Conference speakers include book and library authors, academics, C++ Standard Committee members, tool builders, architects, and engineers. With our very high presenter-to-audience ratio, attendees will have ample opportunity for one-on-one interaction with leaders who are currently defining the state of the art in C++. Dave Abrahams, the conference co-chair, writes, "We planned for an expansion, but even I am surprised at the presenter response and the resulting depth of this year's program. I'm preparing for a flood of new attendees." Reserve your place today at http://cppnow.org/registration C++ Now! 2012, held May 13-18 in Aspen Colorado is hosted by Boost in cooperation with ACM. * Complete program: http://cppnow.org/schedule * Speakers: http://cppnow.org/participants * Registration: http://cppnow.org/registration Jon

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