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Boost.Test Documentation
by James Hamlin 17 Aug '07

17 Aug '07

Hi, I've begun using Boost.Test to construct test suites for a project, and it looks like it does a great job and is full of nice features (I really like the auto unit tests). But I have a big complaint: the documentation is pretty poor. I had a hard time getting a simple example off the ground, because it wasn't clear that I had to link to parts of the library. This was a surprise since most of Boost is templated and so is available entirely through the headers. I had to dig a bit to find the comment about the header that includes the main() code and other concrete functions. In addition, many of the examples are missing, and some of those that are available require the linking I mentioned but fail to note this, adding to my initial confusion. Lastly, the English grammar is very rough in parts, and while I understand that English may not be the primary language of the author, it can be a big hurdle to get started using the library when one has to grapple with the documentation to understand the intentions of the author. I don't mean to rant - the library is great, and I've already found it useful - but I'd love to get more out of it, and clean, clear, and thorough documentation will get me and others started with much less head scratching and frustration.<boost-test%20at%20emailaccount%20dot%20com%20%28please%20unobscure%29> Sincerely, James Hamlin Postscript: This is Boost-users, but I assume Gennadiy Rozental or somebody else with the knowledge and ability to update the documentation will see this message.

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[multi_array]BOOST_NO_SFINAE Warnings
by Mark Ruzon 16 Aug '07

16 Aug '07

I recently upgraded to 1.34.1, gcc 3.4.6, and certain new changes in multi_array don't make sense to me: In view.hpp: template <class BaseList> #ifdef BOOST_NO_SFINAE void #else typename disable_if<typename boost::is_integral<BaseList>::type,void >::type #endif reindex(const BaseList& values) { boost::function_requires< detail::multi_array::CollectionConcept<BaseList> >(); boost::detail::multi_array:: copy_n(values.begin(),num_dimensions(),index_base_list_.begin()); origin_offset_ = this->calculate_indexing_offset(stride_list_,index_base_list_); } multi_array_ref.hpp has a similar function except for the last function call. Both give me warnings because BOOST_NO_SFINAE is not defined, and so reindex has a non-void return type but does not actually return anything. I can get rid of it by #defining this constant, but it seems like a bug in the code. Will someone more knowledgeable shed some light on this, please? Do I need to #define BOOST_NO_SFINAE? Thanks, Mark Ruzon P.S. Apologies if this is the second post asking this question.

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[iostreams] file sink/source and wide char paths?
by Michael Ellery 16 Aug '07

16 Aug '07

it looks like the file_sink and file_source classes in iostreams take std::string for the file path. Was this intentional? I'm not sure what the consensus is on wide char file system paths, but it seems like they are supported by the filesystem package, for instance. Should I just convert my wide char paths to narrow char when it comes to using them with file_sink/file_source -- or is there a better way? Thanks, Mike Ellery

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Unregistered Class Exception - Boost Serialization
by Jason Gorski 16 Aug '07

16 Aug '07

Hello, I have been using the Boost Serialization libraries on a project of mine and so far they have worked very well. However, I have been unable to properly load derived objects using a base class pointer. The following code generates an unregistered class exception: #include <iostream> #include <sstream> #include <iomanip> #include <string> #include <sstream> #include <boost/archive/text_oarchive.hpp> #include <boost/archive/text_iarchive.hpp> #include <boost/serialization/export.hpp> class Base_Class { public: friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, const unsigned int version) { // empty } virtual void print()=0; }; class Derived_Class: public Base_Class { public: int i1; int i2; int i3; friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, const unsigned int version) { ar & boost::serialization::base_object<Base_Class>(*this); ar & i1; ar & i2; ar & i3; } void print(){ std::cout << "i am a derived class object" << std::endl; } }; BOOST_CLASS_EXPORT(Derived_Class) /***************************************** Main *****************************************/ int main() { Derived_Class derived_send; derived_send.i1=12; derived_send.i2=13; derived_send.i3=14; Base_Class * base_ptr; Derived_Class * derived_recv; // save derived class std::ostringstream output_stream; boost::archive::text_oarchive output_archive( output_stream ); output_archive & derived_send; // load using base class ptr std::istringstream input_stream( output_stream.str() ); boost::archive::text_iarchive input_archive( input_stream ); input_archive & base_ptr; derived_recv = (Derived_Class*) base_ptr; derived_recv->print(); } From reading the documentation, it seems as if this should work fine. Am I missing something? Thanks in advance, Jason -- Jason Gorski Research Engineer Oasis Advanced Engineering, Inc. (248)373-9800 x 269 gorski(a)OasisAdvancedEngineering.com

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asio example compile error
by ope 16 Aug '07

16 Aug '07

Hi, I try to compile the asio example at http://asio.sourceforge.net/boost_asio_0_3_7/libs/asio/doc/tutorial/tuttime… using boost 1.34.0 with latest sf.com release of boost_asio in directory extra/boost and lib_system of asio is in directory build/lib. The error attached occoured. What did I wrong? All headers seems to be found. Thanks, Olaf $ g++ asio.cpp -o asio -I /usr/local/include/ -I extra/boost/ -L build/lib/ -static -lboost_system-gcc41-mt-0_1 extra/boost/boost/asio/detail/bind_handler.hpp: In member function »void boost::asio::detail::binder1<Handler, Arg1>::operator()() [with Handler = void (*)(const boost::asio::error&), Arg1 = boost::system::error_code]«: extra/boost/boost/asio/handler_invoke_hook.hpp:63: instantiated from »void boost::asio::asio_handler_invoke(Function, ...) [with Function = boost::asio::detail::binder1<void (*)(const boost::asio::error&), boost::system::error_code>]« extra/boost/boost/asio/detail/handler_invoke_helpers.hpp:39: instantiated from »void asio_handler_invoke_helpers::invoke(const Function&, Context*) [with Function = boost::asio::detail::binder1<void (*)(const boost::asio::error&), boost::system::error_code>, Context = void (*)(const boost::asio::error&)]« extra/boost/boost/asio/detail/bind_handler.hpp:72: instantiated from »void boost::asio::detail::asio_handler_invoke(const Function&, boost::asio::detail::binder1<Handler, Arg1>*) [with Function = boost::asio::detail::binder1<void (*)(const boost::asio::error&), boost::system::error_code>, Handler = void (*)(const boost::asio::error&), Arg1 = boost::system::error_code]« extra/boost/boost/asio/detail/handler_invoke_helpers.hpp:39: instantiated from »void asio_handler_invoke_helpers::invoke(const Function&, Context*) [with Function = boost::asio::detail::binder1<void (*)(const boost::asio::error&), boost::system::error_code>, Context = boost::asio::detail::binder1<void (*)(const boost::asio::error&), boost::system::error_code>]« extra/boost/boost/asio/detail/task_io_service.hpp:412: instantiated from »static void boost::asio::detail::task_io_service<Task>::handler_wrapper<Handler>::do_call(boost::asio::detail::task_io_service<Task>::handler_base*) [with Handler = boost::asio::detail::binder1<void (*)(const boost::asio::error&), boost::system::error_code>, Task = boost::asio::detail::epoll_reactor<false>]« extra/boost/boost/asio/detail/task_io_service.hpp:392: instantiated from »boost::asio::detail::task_io_service<Task>::handler_wrapper<Handler>::handler_wrapper(Handler) [with Handler = boost::asio::detail::binder1<void (*)(const boost::asio::error&), boost::system::error_code>, Task = boost::asio::detail::epoll_reactor<false>]« extra/boost/boost/asio/detail/handler_alloc_helpers.hpp:138: instantiated from »boost::asio::detail::handler_ptr<Alloc_Traits>::handler_ptr(boost::asio::detail::raw_handler_ptr<Alloc_Traits>&, Arg1&) [with Arg1 = boost::asio::detail::binder1<void (*)(const boost::asio::error&), boost::system::error_code>, Alloc_Traits = boost::asio::detail::handler_alloc_traits<boost::asio::detail::binder1<void (*)(const boost::asio::error&), boost::system::error_code>, boost::asio::detail::task_io_service<boost::asio::detail::epoll_reactor<false> >::handler_wrapper<boost::asio::detail::binder1<void (*)(const boost::asio::error&), boost::system::error_code> > >]« extra/boost/boost/asio/detail/task_io_service.hpp:180: instantiated from »void boost::asio::detail::task_io_service<Task>::post(Handler) [with Handler = boost::asio::detail::binder1<void (*)(const boost::asio::error&), boost::system::error_code>, Task = boost::asio::detail::epoll_reactor<false>]« extra/boost/boost/asio/impl/io_service.ipp:125: instantiated from »void boost::asio::io_service::post(Handler) [with CompletionHandler = boost::asio::detail::binder1<void (*)(const boost::asio::error&), boost::system::error_code>]« extra/boost/boost/asio/detail/deadline_timer_service.hpp:169: instantiated from »void boost::asio::detail::deadline_timer_service<Time_Traits, Timer_Scheduler>::wait_handler<Handler>::operator()(const boost::system::error_code&) [with Handler = void (*)(const boost::asio::error&), Time_Traits = boost::asio::time_traits<boost::posix_time::ptime>, Timer_Scheduler = boost::asio::detail::epoll_reactor<false>]« extra/boost/boost/asio/detail/timer_queue.hpp:243: instantiated from »static void boost::asio::detail::timer_queue<Time_Traits>::timer<Handler>::invoke_handler(boost::asio::detail::timer_queue<Time_Traits>::timer_base*, const boost::system::error_code&) [with Handler = boost::asio::detail::deadline_timer_service<boost::asio::time_traits<boost::posix_time::ptime>, boost::asio::detail::epoll_reactor<false> >::wait_handler<void (*)(const boost::asio::error&)>, Time_Traits = boost::asio::time_traits<boost::posix_time::ptime>]« extra/boost/boost/asio/detail/timer_queue.hpp:234: instantiated from »boost::asio::detail::timer_queue<Time_Traits>::timer<Handler>::timer(const typename Time_Traits::time_type&, Handler, void*) [with Handler = boost::asio::detail::deadline_timer_service<boost::asio::time_traits<boost::posix_time::ptime>, boost::asio::detail::epoll_reactor<false> >::wait_handler<void (*)(const boost::asio::error&)>, Time_Traits = boost::asio::time_traits<boost::posix_time::ptime>]« extra/boost/boost/asio/detail/timer_queue.hpp:68: instantiated from »bool boost::asio::detail::timer_queue<Time_Traits>::enqueue_timer(const typename Time_Traits::time_type&, Handler, void*) [with Handler = boost::asio::detail::deadline_timer_service<boost::asio::time_traits<boost::posix_time::ptime>, boost::asio::detail::epoll_reactor<false> >::wait_handler<void (*)(const boost::asio::error&)>, Time_Traits = boost::asio::time_traits<boost::posix_time::ptime>]« extra/boost/boost/asio/detail/epoll_reactor.hpp:325: instantiated from »void boost::asio::detail::epoll_reactor<Own_Thread>::schedule_timer(boost::asio::detail::timer_queue<Time_Traits>&, const typename Time_Traits::time_type&, Handler, void*) [with Time_Traits = boost::asio::time_traits<boost::posix_time::ptime>, Handler = boost::asio::detail::deadline_timer_service<boost::asio::time_traits<boost::posix_time::ptime>, boost::asio::detail::epoll_reactor<false> >::wait_handler<void (*)(const boost::asio::error&)>, bool Own_Thread = false]« extra/boost/boost/asio/detail/deadline_timer_service.hpp:183: instantiated from »void boost::asio::detail::deadline_timer_service<Time_Traits, Timer_Scheduler>::async_wait(boost::asio::detail::deadline_timer_service<Time_Traits, Timer_Scheduler>::implementation_type&, Handler) [with Handler = void (*)(const boost::asio::error&), Time_Traits = boost::asio::time_traits<boost::posix_time::ptime>, Timer_Scheduler = boost::asio::detail::epoll_reactor<false>]« extra/boost/boost/asio/deadline_timer_service.hpp:153: instantiated from »void boost::asio::deadline_timer_service<TimeType, TimeTraits>::async_wait(typename boost::asio::detail::deadline_timer_service<TimeTraits, boost::asio::detail::epoll_reactor<false> >::implementation_type&, WaitHandler) [with WaitHandler = void (*)(const boost::asio::error&), TimeType = boost::posix_time::ptime, TimeTraits = boost::asio::time_traits<boost::posix_time::ptime>]« extra/boost/boost/asio/basic_deadline_timer.hpp:374: instantiated from »void boost::asio::basic_deadline_timer<Time, TimeTraits, TimerService>::async_wait(WaitHandler) [with WaitHandler = void (*)(const boost::asio::error&), Time = boost::posix_time::ptime, TimeTraits = boost::asio::time_traits<boost::posix_time::ptime>, TimerService = boost::asio::deadline_timer_service<boost::posix_time::ptime, boost::asio::time_traits<boost::posix_time::ptime> >]« asio.cpp:15: instantiated from here extra/boost/boost/asio/detail/bind_handler.hpp:39: Fehler: ungültige Initialisierung einer Referenz des Typs »const boost::asio::error&« von Ausdruck des Typs »boost::system::error_code«

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[Announcement] Boost joins the Software Freedom Conservancy
by Beman Dawes 16 Aug '07

16 Aug '07

Effective August 10th, 2007, Boost became a member project of the Software Freedom Conservancy, http://conservancy.softwarefreedom.org. This means that Boost is now part of a legal entity under US law, and tax-exempt under section 501(c)(3) of the US tax regulations. Although this doesn't have much short-term effect, it lets us move forward with BoostCon 2008 planning with less administrative delay. Long-term, being part of a non-profit organization allows Boost to continue to grow and prosper, and to raise money if that becomes useful. After considering the option of starting our own foundation (a huge amount of work), the Boost moderators decided that joining the Software Freedom Conservancy was a better option. The SFC provides the same legal abilities of a foundation at NO cost to the Boost project. It also minimizes the amount of legal and administrative hassles for project members -- allowing us to stay focused on technical matters rather than tax law. In addition, we are free to leave the SFC and create our own foundation at a later time if we decide that the SFC is not serving us well. Boost is not alone -- some other well known open source projects have also joined the SFC (eg: Samba, Wine). For those interested in the details, see a copy of the legal agreement at svn.boost.org/svn/boost/trunk/more/BoostSponsorshipAgreement.pdf I signed for Boost, since I was the founder and am the owner of the boost.org domain name. Dave Abrahams gets the credit for working out the details of the SFC agreement, with the help of the other moderators. --Beman

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Boost Serialization tracking issues
by gast128 16 Aug '07

16 Aug '07

Dear all, I was trying to use the Boost Serialization library again, but I ran into a problem which cost me a full day. The Boost Serialization library is a very handy library, but often when I use it I run into problems which cost me days. This time I try to serialize just 'track_never' objects. First of all the compiler firewall which is built in the library does not work when using the nvp macro: void Foo() { boost::archive::xml_oarchive oa(...) SomeStruct s; oa << s; // compile time error oa << BOOST_SERIALIZATION_NVP(s); //ok } But this wasn't the real problem. I was looping to serialize non tracking objects: void Bla() { boost::archive::xml_oarchive oa(...) for (int i = 0; i < 1000; ++i) { const SomeStruct s; oa << s; } } However the library did track them by pointer due to a previous request to serialize a pointer. It decides this on a call to 'basic_serializer::serialized_as_pointer' deep in the library. struct SomeStructHolder { SomeStructHolder() : m_p(NULL){} template <class Archive> void serialize(Archive& ar, const unsigned int /*version*/) { ar & BOOST_SERIALIZATION_NVP(m_p); } const SomeStruct* m_p; }; somewhere else: void Bla() { boost::archive::xml_oarchive oa(...) const SomeStructHolder holder; oa << holder; } So this is again an unexpected property of the library. Maybe the ambition for automatic object tracking is too high, and specify it explicitly per class / per archiving operation would be more work for the user, but also clearer. And still the original problem was too find out if Boost Serialization could also be used on a per demand loading of (value-)objects: in my problem the final storage can be potential bigger than computer memory, so I was wondering if objects could be loaded on demand (instead of all in once). wkr, me

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ScopeExit Review Reminder
by Jody Hagins 16 Aug '07

16 Aug '07

We have received only a few reviews so far. The review ends in less than a week, so time is running short. Thanks! >From the original announcement... The review period for Scope Exit Time Series, submitted by Alexander Nasonov, runs from Monday, August 13 until Wednesday, August 22. >From the documentation: Nowadays, every C++ developer is familiar with RAII technique. It binds resource acquisition and release to initialization and destruction of a variable that holds the resource. But there are times when writing a special class for such variable is not worth the effort. This is when ScopeExit macro comes into play. You put resource acquisition directly in your code and next to it you write a code that releases the resource. Note that ScopeExit uses PP macros and relies on Boost.Typeof. The latest version can is here: http://boost-consulting.com/vault/index.php?action=downloadfile&filename=sc… It's available also at http://tinyurl.com/2z6qg2 Online documentation is here: http://194.6.223.221/~nasonov/scope_exit-0.04/libs/scope_exit/doc/html/inde… >From the review guidelines here: http://boost.org/more/formal_review_process.htm ... Boost mailing list members are encouraged to submit Formal Review comments: * Publicly on the mailing list. * Privately to the Review Manager. Private comments to a library submitter may be helpful to her or him, but won't help the Review Manager reach a decision, so the other forms are preferred. What to include in Review Comments Your comments may be brief or lengthy, but basically the Review Manager needs your evaluation of the library. If you identify problems along the way, please note if they are minor, serious, or showstoppers. Here are some questions you might want to answer in your review: * What is your evaluation of the design? * What is your evaluation of the implementation? * What is your evaluation of the documentation? * What is your evaluation of the potential usefulness of the library? * Did you try to use the library? With what compiler? Did you have any problems? * How much effort did you put into your evaluation? A glance? A quick reading? In-depth study? * Are you knowledgeable about the problem domain? And finally, every review should answer this question: * Do you think the library should be accepted as a Boost library? Be sure to say this explicitly so that your other comments don't obscure your overall opinion. Thanks in advance to every for your participation in this review.

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[Fwd: boost serialization excessive warning messages]
by Fei Liu 16 Aug '07

16 Aug '07

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Boost regex Java Regex package compatibility
by Sudarshan Gaikaiwari 16 Aug '07

16 Aug '07

Hello Boost Experts Here is my situation. Users write regular expressions which act as input to our programs and are used to perform matches. Currently the code base is Java and uses the java.util.regex package to handle regular expressions. I need to convert this code to C++ and intend to use boost regex. How compatible is boost regex with Java regex? I have looked at Java regex documentation here http://java.sun.com/j2se/1.5.0/docs/api/java/util/regex/Pattern.html to note the differences between Java regex and Perl 5 regexs. Are these the only with boost regex also? -- Sudarshan Gaikaiwari www.sudarshan.org sudarshan(a)acm.org

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exceptions from regexp library usage
by Venkat Rangan 16 Aug '07

16 Aug '07

Hi, I get the following exception while using a boost regexp matching libraries (with Windows Visual Studio, 7.1 environment). Setup: static RegexClass::RegularExpression re_exp; bool CMyclass::parseExpression(string expression) { LoggerPtr logger = Logger::getRootLogger(); ostringstream oss; RegexClass::RegularExpression *re = &re_exp; re->Expression = expression; RegexClass::RegularExpression::ExpressionErrorCode eec = re->ParseExpression(); if (eec == RegexClass::RegularExpression::REG_NOERROR) { oss << "Parse successful: " << expression; logger->info(oss.str()); return true; } ... } Matching call: bool CMyClass::matchSpec(RegexClass::RegularExpression *pRe, const char *stringToMatch) { pRe->SetStringToMatch(stringToMatch); if (pRe->Match()) { return true; } return false; } Exception while using expression matcher on Windows Server 2003 Platforms: Exception Stack Trace 0x0343c900 0x00457374 boost::re_detail::reg_grep2<boost::re_detail::grep_search_predicate<std: :basic_string<char,std::char_traits<char>,std::allocator<char> >::iterator,boost::detail::allocator<char> >,std::basic_string<char,std::char_traits<char>,std::allocator<char> >::iterator,char,boost::regex_traits<char>,boost::detail::allocator<char >,boost::detail::allocator<char> > 0x00000044 0x0343c924 0x0045a65b boost::regex_search<std::basic_string<char,std::char_traits<char>,std::a llocator<char>>::iterator,boost::detail::allocator<char>,char,boost::reg ex_traits<char>,boost::detail::allocator<char> > 0x0000003b 0x0343c970 0x0045ae66 RegexClass::RegularExpression::Match 0x000001c6 Sometimes, I get the following exception: Stack Trace 0x037dc938 0x0045db6e RegexClass::RegularExpressionPimpl::GetMatchingInformation 0x0000027e 0x037dc970 0x0045af19 RegexClass::RegularExpression::Match 0x00000279 0x037dc9a0 0x004370b1 CMyClass::matchSpec 0x00000091 at myclass.cpp(349) Any help would be much appreciated. Thanks.

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Link errors using Boost & STLPort with VC8
by Jason Ivey 16 Aug '07

16 Aug '07

I am attempting to compile and link a small test application using STLPort_5.1.3, boost_1_34_1 and MSVC8 sp1. Everything works fine when I don't have to link against any boost libraries. To test linking against the boost static libraries I wrote a simple little test app that used the boost::regex library and ran into errors. I am not completely sure that this is a boost issue but since I can compile and link programs without any problems that don't use boost binaries I wasn't sure of who else to turn to. The linker error I am getting is: 1>LINK : fatal error LNK1104: cannot open file 'stlportstld_x.5.1.lib' The problem is that all of the stlport libraries are named stlportstld.5.1.lib or similar. I did try to just rename the library to make it match but, of course, I got a boat load of unresolved external linker errors pointing to names such as "stlpdx_std::basic_string." Looking at a dumpbin output of the actual regex library it is linking against, libboost_regex-vc80-mt-sgdp-1_34_1.lib, I found linker directives of the form: /DEFAULTLIB:"stlportstld_x.5.1.lib" /DEFAULTLIB:"libcpmtd" /DEFAULTLIB:"LIBCMTD" /DEFAULTLIB:"OLDNAMES" I couldn't find anywhere that boost had put those directives in the libraries but I could be missing something so I also did a dumpbin of one of the stlport libraries, stlportd_static.5.1.lib, and only found the following linker directives: /DEFAULTLIB:"LIBCMTD" /DEFAULTLIB:"OLDNAMES" I have to believe there are at least a few companies out there who have replaced the shipping MSVC STL for testing purposes, if for no other reason, and are also using Boost so hopefully I'm just missing something obvious. Below are the steps I followed to compile both sets of libraries and the test application. Let me know if anything appears to be off or if there is simply a better/easier way. Thanks, Jason Ivey Open command prompt and run: "%VS80COMNTOOLS%\vsvars32.bat" STLPort_5.1.3 build\lib\configure -c msvc8 nmake /fmsvc.mak install Boost_1_34_1 edit tools\build\v2\user-config.jam added line 45 with using stlport : : d:\\build\\stlport\\stlport d:\\build\\stlport\\lib ; bjam --toolset=msvc stdlib=stlport --with-regex stage Build Test Application set include=d:\build\stlport\stlport;D:\build\boost_1_34_1;%include% set lib=d:\build\stlport\lib;D:\build\boost_1_34_1\stage\lib;%lib% call "%VS80COMNTOOLS%\..\IDE\devenv.exe" /useenv

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function/bind - passing function pointer to C API
by Nicholas Yue 16 Aug '07

16 Aug '07

Hi, I am attempting to use Boost bind and function to help me pass a member function as a function pointer to the GLUT C-library. I have difficulty understanding the usage of bind and function in the Boost library. When I attempt to pass what I thought was a function pointer, the compiler indicated that it is actually not a function pointer. class MyGlut { public: MyGlut(); virtual ~MyGlut(); void loop(int argc, char **argv); void draw(void); void displayFunc(boost::function<void()> func); private: boost::function<void()> display_callback; }; void MyGlut::displayFunc(boost::function<void()> func) { glutDisplayFunc(func); // ERROR IN COMPILATION } void MyGlut::loop(int argc, char **argv) { glutInit(&argc,argv); glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH | GLUT_MULTISAMPLE); glutCreateWindow("Hello World"); //glutDisplayFunc(redraw); // Original way to pass C-function pointer displayFunc( boost::bind(&MyGlut::draw, *this) ); } Regards

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Need ideas...
by Noah Roberts 16 Aug '07

16 Aug '07

I am trying to generalize the concept of putting database data into boost::tuple objects. I'm thinking syntax similar to something like so: typedef boost::tuple<int, double, std::string> row; row r = SqlQuery<row>::run_query(db, "select * from x"); I imagine something like so being contained in the processing: TUPLE t; ... t.get<X>() = boost::lexical_cast< typename boost::tuples::element<X,TUPLE>::type >(data[X]); // data is char ** Where X is the index of the element and the entire tuple is iterated in this manner. I thought maybe there would be something in MPL that could help but I'm not seeing it. Anyone got any bright ideas?

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BOOST pass an object to python code
by alex＠gorex.com.hk 16 Aug '07

16 Aug '07

Hello, I am new in this list. I would like to ask a quesiton about the linkage between BOOST and Python. I want to use C++ to trigger a Python code so that when I change anything inside Python, my C++ can know the changes and get the result back. So how can I pass an object from C++ to Python? and return the result? Here is the code that embedded the Class. class CppClass { public: int getNum() { return 7; } }; #include <boost/python.hpp> using namespace boost::python; int main( int argc, char ** argv ) { try { Py_Initialize(); object main_module(( handle<>(borrowed(PyImport_AddModule("__main__"))))); object main_namespace = main_module.attr("__dict__"); main_namespace["CppClass"] = class_<CppClass>("CppClass") .def("getNum",&CppClass::getNum); handle<> ignored(( PyRun_String( ""cpp = CppClass()\n" "print cpp.getNum()\n"", Py_file_input, main_namespace.ptr(), main_namespace.ptr() ) )); } catch( error_already_set ) { PyErr_Print(); } } Thanks

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[OT] Stroustrup video on slashdot
by Christian Henning 15 Aug '07

15 Aug '07

Hi there, some of you might be interested in watching his talk. http://it.slashdot.org/it/07/08/13/0818238.shtml I found this interview with Bjarne quite interesting: ----------- Interviewer: Well, it's been a few years since you changed the world of software design, how does it feel, looking back? Stroustrup: Actually, I was thinking about those days, just before you arrived. Do you remember? Everyone was writing 'C' and, the trouble was, they were pretty damn good at it. Universities got pretty good at teaching it, too. They were turning out competent - I stress the word 'competent' - graduates at a phenomenal rate. That's what caused the problem. Interviewer: Problem? Stroustrup: Yes, problem. Remember when everyone wrote Cobol? Interviewer: Of course, I did too Stroustrup: Well, in the beginning, these guys were like demi-gods. Their salaries were high, and they were treated like royalty. Interviewer: Those were the days, eh? Stroustrup: Right. So what happened? IBM got sick of it, and invested millions in training programmers, till they were a dime a dozen. Interviewer: That's why I got out. Salaries dropped within a year, to the point where being a journalist actually paid better. Stroustrup: Exactly. Well, the same happened with 'C' programmers. Interviewer: I see, but what's the point? Stroustrup: Well, one day, when I was sitting in my office, I thought of this little scheme, which would redress the balance a little. I thought 'I wonder what would happen, if there were a language so complicated, so difficult to learn, that nobody would ever be able to swamp the market with programmers? Actually, I got some of the ideas from X10, you know, X windows. That was such a bitch of a graphics system, that it only just ran on those Sun 3/60 things. They had all the ingredients for what I wanted. A really diculously complex syntax, obscure functions, and pseudo-OO structure. Even now, nobody writes raw X-windows code. Motif is the only way to go if you want to retain your sanity. Interviewer: You're kidding...? Stroustrup: Not a bit of it. In fact, there was another problem. Unix was written in 'C', which meant that any 'C' programmer could very easily become a systems programmer. Remember what a mainframe systems programmer used to earn? Interviewer: You bet I do, that's what I used to do. Stroustrup: OK, so this new language had to divorce itself from Unix, by hiding all the system calls that bound the two together so nicely. This would enable guys who only knew about DOS to earn a decent living too. Interviewer: I don't believe you said that... Stroustrup: Well, it's been long enough, now, and I believe most people have figured out for themselves that C++ is a waste of time but, I must say, it's taken them a lot longer than I thought it would. Interviewer: So how exactly did you do it? Stroustrup: It was only supposed to be a joke, I never thought people would take the book seriously. Anyone with half a brain can see that object-oriented programming is counter-intuitive, illogical and inefficient. Interviewer: What? Stroustrup: And as for 're-useable code' - when did you ever hear of a company re-using its code? Interviewer: Well, never, actually, but... Stroustrup: There you are then. Mind you, a few tried, in the early days. There was this Oregon company - Mentor Graphics, I think they were called - really caught a cold trying to rewrite everything in C++ in about '90 or '91. I felt sorry for them really, but I thought people would learn from their mistakes. Interviewer: Obviously, they didn't? Stroustrup: Not in the slightest. Trouble is, most companies hush-up all their major blunders, and explaining a $30 million loss to the shareholders would have been difficult. Give them their due, though, they made it work in the end. Interviewer: They did? Well, there you are then, it proves O-O works. Stroustrup: Well, almost. The executable was so huge, it took five minutes to load, on an HP workstation, with 128MB of RAM. Then it ran like treacle. Actually, I thought this would be a major stumbling-block, and I'd get found out within a week, but nobody cared. Sun and HP were only too glad to sell enormously powerful boxes, with huge resources just to run trivial programs. You know, when we had our first C++ compiler, at AT&T, I compiled 'Hello World', and couldn't believe the size of the executable. 2.1MB Interviewer: What? Well, compilers have come a long way, since then. Stroustrup: They have? Try it on the latest version of g++ - you won't get much change out of half a megabyte. Also, there are several quite recent examples for you, from all over the world. British Telecom had a major disaster on their hands but, luckily, managed to scrap the whole thing and start again. They were luckier than Australian Telecom. Now I hear that Siemens is building a dinosaur, and getting more and more worried as the size of the hardware gets bigger, to accommodate the executables. Isn't multiple eritance a joy? Interviewer: Yes, but C++ is basically a sound language. Stroustrup: You really believe that, don't you? Have you ever sat down and worked on a C++ project? Here's what happens: First, I've put in enough pitfalls to make sure that only the most trivial projects will work first time. Take operator overloading. At the end of the project, almost every module has it, usually, because guys feel they really should do it, as it was in their training course. The same operator then means something totally different in every module. Try pulling that lot together, when you have a red or so modules. And as for data hiding. God, I sometimes can't help laughing when I hear about the problems companies have making their modules talk to each other. I think the word 'synergistic' was specially invented to twist the knife in a project manager's ribs. Interviewer: I have to say, I'm beginning to be quite appalled at all this. You say you did it to raise programmers' salaries? That's obscene. Stroustrup: Not really. Everyone has a choice. I didn't expect the thing to get so much out of hand. Anyway, I basically succeeded. C++ is dying off now, but programmers still get high salaries - especially those poor devils who have to maintain all this crap. You do realise, it's impossible to maintain a large C++ software module if you didn't actually write it? Interviewer: How come? Stroustrup: You are out of touch, aren't you? Remember the typedef? Interviewer: Yes, of course. Stroustrup: Remember how long it took to grope through the header files only to find that 'RoofRaised' was a double precision number? Well, imagine how long it takes to find all the implicit typedefs in all the Classes in a major project. Interviewer: So how do you reckon you've succeeded? Stroustrup: Remember the length of the average-sized 'C' project? About 6 months. Not nearly long enough for a guy with a wife and kids to earn enough to have a decent standard of living. Take the same project, design it in C++ and what do you get? I'll tell you. One to two years. Isn't that great? All that job security, just through one mistake of judgement. And another thing. The universities haven't been teaching 'C' for such a long time, there's now a shortage of decent 'C' programmers. Especially those who know nything about Unix systems programming. How many guys would know what to do with 'malloc', when they've used 'new' all these years - and never bothered to check the return code. In fact, most C++ programmers throw away their return codes. Whatever happened to good ol' '-1'? At least you knew you had an error, without bogging the thing down in all that 'throw' 'catch' 'try' stuff. Interviewer: But, surely, inheritance does save a lot of time? Stroustrup: Does it? Have you ever noticed the difference between a 'C' project plan, and a C++ project plan? The planning stage for a C++ project is three times as long. Precisely to make sure that everything which should be inherited is, and what shouldn't isn't. Then, they still get it wrong. Whoever heard of memory leaks in a 'C' program? Now finding them is a major industry. Most companies give up, and send the product out, knowing it leaks like a sieve, simply to avoid the expense of tracking them all down. Interviewer: There are tools... Stroustrup: Most of which were written in C++. Interviewer: If we publish this, you'll probably get lynched, you do realise that? Stroustrup: I doubt it. As I said, C++ is way past its peak now, and no company in its right mind would start a C++ project without a pilot trial. That should convince them that it's the road to disaster. If not, they deserve all they get. You know, I tried to convince Dennis Ritchie to rewrite Unix in C++. Interviewer: Oh my God. What did he say? Stroustrup: Well, luckily, he has a good sense of humor. I think both he and Brian figured out what I was doing, in the early days, but never let on. He said he'd help me write a C++ version of DOS, if I was interested. Interviewer: Were you? Stroustrup: Actually, I did write DOS in C++, I'll give you a demo when we're through. I have it running on a Sparc 20 in the computer room. Goes like a rocket on 4 CPU's, and only takes up 70 megs of disk. Interviewer: What's it like on a PC? Stroustrup: Now you're kidding. Haven't you ever seen Windows '95? I think of that as my biggest success. Nearly blew the game before I was ready, though. Interviewer: You know, that idea of a Unix++ has really got me thinking. Somewhere out there, there's a guy going to try it. Stroustrup: Not after they read this interview. Interviewer: I'm sorry, but I don't see us being able to publish any of this. Stroustrup: But it's the story of the century. I only want to be remembered by my fellow programmers, for what I've done for them. You know how much a C++ guy can get these days? Interviewer: Last I heard, a really top guy is worth $70 - $80 an hour. Stroustrup: See? And I bet he earns it. Keeping track of all the gotchas I put into C++ is no easy job. And, as I said before, every C++ programmer feels bound by some mystic promise to use every damn element of the language on every project. Actually, that really annoys me sometimes, even though it serves my original purpose. I almost like the language after all this time. Interviewer: You mean you didn't before? Stroustrup: Hated it. It even looks clumsy, don't you agree? But when the book royalties started to come in... well, you get the picture. Interviewer: Just a minute. What about references? You must admit, you improved on 'C' pointers. Stroustrup: Hmm. I've always wondered about that. Originally, I thought I had. Then, one day I was discussing this with a guy who'd written C++ from the beginning. He said he could never remember whether his variables were referenced or dereferenced, so he always used pointers. He said the little asterisk always reminded him. Interviewer: Well, at this point, I usually say 'thank you very much' but it hardly seems adequate. Stroustrup: Promise me you'll publish this. My conscience is getting the better of me these days. Interviewer: I'll let you know, but I think I know what my editor will say. Stroustrup: Who'd believe it anyway? Although, can you send me a copy of that tape? Interviewer: I can do that.

3 2

Having trouble with boost thread library
by Fei Liu 15 Aug '07

15 Aug '07

#ifndef UTILS_NETWORK_TCP_CONNECTION_HPP #define UTILS_NETWORK_TCP_CONNECTION_HPP namespace utils{ namespace thread{ template <typename shared_obj_type, typename thread_pool_type, typename serverlet_type> class tcp_connection{ private: int newsockfd; shared_obj_type obj; thread_pool_type pool; serverlet_type serverlet; bool initialized_; public: tcp_connection() : initialized_ (false) {} tcp_connection(int newsockfd, shared_obj_type obj, thread_pool_type pool, serverlet_type serverlet) : newsockfd(newsockfd), obj(obj), pool(pool), serverlet(serverlet), initialized_(true) { } bool initialized() { return initialized_; } bool initialize(int newsockfd, shared_obj_type obj, thread_pool_type pool, serverlet_type serverlet); void operator ()(); }; template <typename shared_obj_type, typename thread_pool_type, typename serverlet_type> bool tcp_connection<shared_obj_type, thread_pool_type, serverlet_type>::initialize (int newsockfd, shared_obj_type obj, thread_pool_type pool, serverlet_type serverlet) { this->newsockfd = newsockfd; this->obj = obj; this->pool = pool; this->serverlet = serverlet; initialized_ = true; return initialized_; } template <typename shared_obj_type, typename thread_pool_type, typename serverlet_type> void tcp_connection<shared_obj_type, thread_pool_type, serverlet_type>::operator() () { //if(initialized_) serverlet_type(newsockfd, obj); <---- causes error pool->release(); } } } #endif main.cpp: provides definition of serverlet_type #include "utils/thread/tcp_server.hpp" #include "utils/thread/thread_pool.h" #include <boost/shared_ptr.hpp> #include <vector> #include <iostream> typedef std::vector<int> shared_obj_type; typedef boost::shared_ptr<boost_thread::thread_pool> thread_pool_type; typedef void (*serverlet_type)(int, shared_obj_type); void servlet(int sock, shared_obj_type ){ std::cout << "got a new socket for a new connection: " << sock << std::endl; } int main(){ shared_obj_type x; thread_pool_type p( new boost_thread::thread_pool(20) ); utils::thread::tcp_server<shared_obj_type, thread_pool_type, serverlet_type> server; server.initialize(x, p, servlet, 10000, 5); boost::thread s(server); s.join(); } /root/cpp-utils-header-lib/include/utils/thread/tcp_connection.hpp: In member function `void utils::thread::tcp_connection<shared_obj_type, thread_pool_type, serverlet_type>::operator()() [with shared_obj_type = shared_obj_type, thread_pool_type = thread_pool_type, serverlet_type = void (*)(int, shared_obj_type)]': /usr/include/boost/function/function_template.hpp:155: instantiated from `static void boost::detail::function::void_function_obj_invoker0<FunctionObj, R>::invoke(boost::detail::function::function_buffer&) [with FunctionObj = utils::thread::tcp_connection<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type)>, R = void]' /usr/include/boost/function/function_template.hpp:368: instantiated from `void boost::detail::function::basic_vtable0<R, Allocator>::init(FunctionObj, boost::detail::function::function_obj_tag) [with FunctionObj = utils::thread::tcp_connection<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type)>, R = void, Allocator = std::allocator<boost::function_base>]' /usr/include/boost/function/function_template.hpp:298: instantiated from `void boost::detail::function::basic_vtable0<R, Allocator>::init(F) [with F = utils::thread::tcp_connection<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type)>, R = void, Allocator = std::allocator<boost::function_base>]' /usr/include/boost/function/function_template.hpp:277: instantiated from `boost::detail::function::basic_vtable0<R, Allocator>::basic_vtable0(F) [with F = utils::thread::tcp_connection<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type)>, R = void, Allocator = std::allocator<boost::function_base>]' /usr/include/boost/function/function_template.hpp:655: instantiated from `void boost::function0<R, Allocator>::assign_to(Functor) [with Functor = utils::thread::tcp_connection<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type)>, R = void, Allocator = std::allocator<boost::function_base>]' /usr/include/boost/function/function_template.hpp:513: instantiated from `boost::function0<R, Allocator>::function0(Functor, typename boost::enable_if_c< boost::type_traits::ice_not< boost::is_integral<Functor>::value>::value, int>::type) [with Functor = utils::thread::tcp_connection<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type)>, R = void, Allocator = std::allocator<boost::function_base>]' /root/cpp-utils-header-lib/include/utils/thread/tcp_server.hpp:107: instantiated from `void utils::thread::tcp_server<shared_obj_type, thread_pool_type, serverlet_type, accept_fail_policy>::operator()() [with shared_obj_type = shared_obj_type, thread_pool_type = thread_pool_type, serverlet_type = void (*)(int, shared_obj_type), accept_fail_policy = utils::thread::default_accept_fail_policy]' /usr/include/boost/function/function_template.hpp:155: instantiated from `static void boost::detail::function::void_function_obj_invoker0<FunctionObj, R>::invoke(boost::detail::function::function_buffer&) [with FunctionObj = utils::thread::tcp_server<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type), utils::thread::default_accept_fail_policy>, R = void]' /usr/include/boost/function/function_template.hpp:368: instantiated from `void boost::detail::function::basic_vtable0<R, Allocator>::init(FunctionObj, boost::detail::function::function_obj_tag) [with FunctionObj = utils::thread::tcp_server<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type), utils::thread::default_accept_fail_policy>, R = void, Allocator = std::allocator<boost::function_base>]' /usr/include/boost/function/function_template.hpp:298: instantiated from `void boost::detail::function::basic_vtable0<R, Allocator>::init(F) [with F = utils::thread::tcp_server<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type), utils::thread::default_accept_fail_policy>, R = void, Allocator = std::allocator<boost::function_base>]' /usr/include/boost/function/function_template.hpp:277: instantiated from `boost::detail::function::basic_vtable0<R, Allocator>::basic_vtable0(F) [with F = utils::thread::tcp_server<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type), utils::thread::default_accept_fail_policy>, R = void, Allocator = std::allocator<boost::function_base>]' /usr/include/boost/function/function_template.hpp:655: instantiated from `void boost::function0<R, Allocator>::assign_to(Functor) [with Functor = utils::thread::tcp_server<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type), utils::thread::default_accept_fail_policy>, R = void, Allocator = std::allocator<boost::function_base>]' /usr/include/boost/function/function_template.hpp:513: instantiated from `boost::function0<R, Allocator>::function0(Functor, typename boost::enable_if_c< boost::type_traits::ice_not< boost::is_integral<Functor>::value>::value, int>::type) [with Functor = utils::thread::tcp_server<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type), utils::thread::default_accept_fail_policy>, R = void, Allocator = std::allocator<boost::function_base>]' tests/boost_tcp_server_test.cpp:24: instantiated from here /root/cpp-utils-header-lib/include/utils/thread/tcp_connection.hpp:61: error: functional cast expression list treated as compound expression /root/cpp-utils-header-lib/include/utils/thread/tcp_connection.hpp:61: warning: left-hand operand of comma has no effect /root/cpp-utils-header-lib/include/utils/thread/tcp_connection.hpp:61: error: cannot convert `((void)((utils::thread::tcp_connection<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type)>*)this)->utils::thread::tcp_connection<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type)>::newsockfd, ((utils::thread::tcp_connection<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type)>*)this)->utils::thread::tcp_connection<shared_obj_type, thread_pool_type, void (*)(int, shared_obj_type)>::obj)' from type `shared_obj_type' to type `void (*)(int, shared_obj_type)'

1 0

Update: application failed to initialize, bad jmp to malloc?
by David Daeschler 15 Aug '07

15 Aug '07

I'm sorry this post is so long, I'm looking for someone who may have experienced this, or knows enough about what I am rambling about to help me. I haven't been able to run our app built with MINGW for a week now, and It's starting to become a problem. This is a followup to a previous post entitled "Wrong DLL init routine being called?". I am starting a new post because it appears as if the stack traces I was getting before were wrong. I now have more information, and feel I am closer to solving this. When I try to load a test application I'm receiving the message: "The application failed to initialize properly (0xc0000005). Click on OK to terminate the application." I am not using auto-imports, so solutions referring to them have not helped me. I have always been winding up in malloc during the crashes I've been experiencing in calls to DLL initialization routines. I've been able to get a stack trace that lands up inside dllcrt1.c (the STATIC MINGW runtime) and shows me which call to malloc is segfaulting. The stack trace is as follows: #0 0x003e14a0 in malloc () #1 0x003e111c in DllMainCRTStartup@12 (hDll=0x3e0000, dwReason=1, lpReserved=0x22fd30) at dllcrt1.c:56 #2 0x7c9011a7 in ntdll!LdrSetAppCompatDllRedirectionCallback () from C:\WINDOWS\system32\ntdll.dll #3 0x003e0000 in ?? () #4 0x00000001 in ?? () #5 0x003e10c0 in __dll_exit () at dllcrt1.c:149 #6 0x00000000 in ?? () with frame 1 (inside dllcrt1.c) as: (gdb) f 1 #1 0x003e111c in DllMainCRTStartup@12 (hDll=0x3e0000, dwReason=1, lpReserved=0x22fd30) at dllcrt1.c:56 56 first_atexit = (p_atexit_fn*) malloc (32 * sizeof (p_atexit_fn)); Current language: auto; currently c (gdb) list 51 #endif 52 53 /* Initialize private atexit table for this dll. 54 32 is min size required by ANSI */ 55 56 first_atexit = (p_atexit_fn*) malloc (32 * sizeof (p_atexit_fn)); 57 if (first_atexit == NULL ) /* can't allocate memory */ 58 { 59 errno=ENOMEM; 60 return FALSE; Notice line 56. It seems innocent enough, how could a call to malloc be crashing? Well I called malloc from insidge gdb, and it worked fine, so I then dug further in and noticed that the malloc symbol that gdb is seeing is: (gdb) print malloc $1 = {<text variable, no debug info>} 0x40c780 <malloc> 0x40c780, okay, lets see a disassembly: Dump of assembler code for function malloc: 0x0040c780 <malloc+0>: jmp *0x41b1dc So there is a jump to 0x41b1dc, sure enough that lands us inside of: (gdb) disas 0x41b1dc Dump of assembler code for function _imp__malloc: 0x0041b1dc <_imp__malloc+0>: pop %es 0x0041b1dd <_imp__malloc+1>: les (bad),%eax 0x0041b1de <_imp__malloc+2>: ret $0x77 Ahh, import stub that leads us to: (gdb) disas _imp__malloc Dump of assembler code for function msvcrt!malloc: 0x77c2c407 <msvcrt!malloc+0>: mov %edi,%edi 0x77c2c409 <msvcrt!malloc+2>: push %ebp 0x77c2c40a <msvcrt!malloc+3>: mov %esp,%ebp 0x77c2c40c <msvcrt!malloc+5>: cmpl $0x0,0x77c62418 0x77c2c413 <msvcrt!malloc+12>: jne 0x77c2c420 <msvcrt!malloc+25> 0x77c2c415 <msvcrt!malloc+14>: call 0x77c1ef38 <msvcrt!__initenv+77> 0x77c2c41a <msvcrt!malloc+19>: test %eax,%eax 0x77c2c41c <msvcrt!malloc+21>: jne 0x77c2c420 <msvcrt!malloc+25> 0x77c2c41e <msvcrt!malloc+23>: pop %ebp 0x77c2c41f <msvcrt!malloc+24>: ret 0x77c2c420 <msvcrt!malloc+25>: pushl 0x77c61808 0x77c2c426 <msvcrt!malloc+31>: pushl 0x8(%ebp) 0x77c2c429 <msvcrt!malloc+34>: call 0x77c2c3d4 <msvcrt!free+441> 0x77c2c42e <msvcrt!malloc+39>: pop %ecx 0x77c2c42f <msvcrt!malloc+40>: pop %ecx 0x77c2c430 <msvcrt!malloc+41>: pop %ebp 0x77c2c431 <msvcrt!malloc+42>: ret 0x77c2c432 <msvcrt!malloc+43>: int3 0x77c2c433 <msvcrt!malloc+44>: int3 0x77c2c434 <msvcrt!malloc+45>: int3 0x77c2c435 <msvcrt!malloc+46>: int3 0x77c2c436 <msvcrt!malloc+47>: int3 End of assembler dump. Good, this is where I would expect to be, right at home inside of msvcrt. But now take a look at the first frame of our original stack trace. #0 0x003e14a0 in malloc () 0x3e14a0.. Umm, hmmm, wierd. Let's see where that leads us? (gdb) disas 0x3e14a0 Dump of assembler code for function malloc: 0x003e14a0 <malloc+0>: jmp *0x90c0609c I'd hate to say it, but there is no 0x90x0609c. That explains the segfault. Let's see what else is around 0x3e14a0... (gdb) disas 0x3e1490 Dump of assembler code for function _pei386_runtime_relocator: 0x003e1470 <_pei386_runtime_relocator+0>: mov $0x90c03034,%ecx 0x003e1475 <_pei386_runtime_relocator+5>: push %ebp 0x003e1476 <_pei386_runtime_relocator+6>: cmp $0x90c03034,%ecx 0x003e147c <_pei386_runtime_relocator+12>: mov %esp,%ebp 0x003e147e <_pei386_runtime_relocator+14>: jae 0x3e1498 <_pei386_runtime_relocator+40> 0x003e1480 <_pei386_runtime_relocator+16>: mov 0x4(%ecx),%edx 0x003e1483 <_pei386_runtime_relocator+19>: mov (%ecx),%eax 0x003e1485 <_pei386_runtime_relocator+21>: add $0x8,%ecx 0x003e1488 <_pei386_runtime_relocator+24>: add $0x90c00000,%edx 0x003e148e <_pei386_runtime_relocator+30>: add %eax,(%edx) 0x003e1490 <_pei386_runtime_relocator+32>: cmp $0x90c03034,%ecx 0x003e1496 <_pei386_runtime_relocator+38>: jb 0x3e1480 <_pei386_runtime_relocator+16> 0x003e1498 <_pei386_runtime_relocator+40>: pop %ebp 0x003e1499 <_pei386_runtime_relocator+41>: ret End of assembler dump. That looks like static libgcc to me. So is libgcc calling the wrong malloc for some reason? Why? Is this a relocation problem? Is there any way I can fix this? Is there anyone else I should be asking? I am using the dwarf2 GCC 4.2.1, but I had the same results with gcc 3.4.5 (though with less details on the crash) I was thinking that maybe shared libgcc would fix my problem, but I can't seem to link with it. When I specify -shared-libgcc it says I'm missing libgcc_s.a which I can't find anywhere. Details on my setup: $ gcc -v Using built-in specs. Target: mingw32 Configured with: ../gcc-4.2.1-2-src/configure --with-gcc --enable-libgomp --host=mingw32 --build=mingw32 --target=mingw32 --program-suffix=-dw2 --with-arch=i486 --with-tune=generic --disable-werror --prefix=/mingw --with-local-prefix=/mingw --enable-threads --disable-nls --enable-languages=c,c ++,fortran,objc,obj-c++,ada --disable-win32-registry --disable-sjlj-exceptions --enable-libstdcxx-debug --enable-cxx-flags=-fno-function-sections -fno-data-sections --enable-version-specific-runtime-libs --disable-bootstrap Thread model: win32 gcc version 4.2.1-dw2 (mingw32-2) $ld -v GNU ld version 2.17.50 20060824 MINGW runtime is a debug compiled version of mingw-runtime-3.13

1 1

BOOST_NO_IS_ABSTRACT defined for SunPRO CC?
by Sohail Somani 15 Aug '07

15 Aug '07

Hi, In the upgrade to boost 1.34.1, I noticed that the sunpro_cc.hpp config file now defines BOOST_NO_IS_ABSTRACT for the latest compiler. This affects serialization code that used to work with 1.33.1. The relevant change is here: http://svn.boost.org/trac/boost/changeset/32005 I'm wondering, why was this change made since it seems to work? There is no ticket referenced in the commit. Thanks, Sohail

2 3

[program_options] Short program options
by Christian Henning 15 Aug '07

15 Aug '07

Hi there, a while ago I was asking some questions about the short option feature. If I'm not mistaken a short option can only be one letter long. Is that correct to say? In my project I need more than this. So I started to just add the short names to the options list like I would do for all options. But in this case they would share the same variable. Like this: po::options_description settings( "" ); settings.add_options() ( "input_1" , po::value< string >( &_input ) ->default_value( "" ) , "" ) ( "i1" , po::value< string >( &_input ) ->default_value( "" ) , "" ); Both options are pointing to the same variable. For some reasons this code works only for "input_1" and not for "i1". Why is that? If I use --i1="Hallo" the _input is empty. Regards, Christian

3 3

asio's io_service uses too many file descriptors
by pete＠mu.org 15 Aug '07

15 Aug '07

I posted this under a less suitable subject line a week ago, but I got no response. I hope the above live will trigger some help. I 've been doinking around with asio for a few weeks, and I've run into an issue I can't seem to wrap my head around. I've been playing with some code that originally was meant to pound a server with a large amount of packets for benchmarking purposes. It uses threads to launch hundreds of threads per second. When I replaced the old socket code with asio, and used a single io_service with run being called within each thread, I run out of file descriptors very quickly, and if I use a single io_service within each thread it's the same thing but the performance seems worse. Needless to say, this seems like a real limitation and I'm hoping I'm just being limited by my own misunderstanding, because I'm really enjoying the portability of asio. The docs that are there seem great, but there seems to be a lot more the library can do that I am missing out on, and I think the docs seem like they are not mentioning a lot of what asio an do. Can someone point me in the right direction for launching 1-to-N threads with a single send_to and a single receive_from within each thread that doesn't take the hit I'm seeing? It seems to me, that it's obvious that the io-service design is the difference, because I don't get the issue at all when I use plain old sockets, and the OS thread limit is then the only limitation. Any help would be greatly appreciated. FYI, I've done most of my experimenting on Linux and OSX. I can send some code samples if needed, but I think the problem should be apparent if anyone else has tried to use asio with large amounts of threads. Thanks, Pete

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boost serialization excessive warning messages
by Fei Liu 15 Aug '07

15 Aug '07

Hi Group, I am getting multiple warning messages like the following from boost serialization library: /usr/include/boost/archive/detail/iserializer.hpp:124: warning: unused parameter 'flags' I am pretty sure this is a common issue but I haven't found any clue through the web. Is there a way to turn off the warning through proper coding? I am using gcc on linux. Fei

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[iostreams] Different character type in a filtering stream [C1]
by frederic.mayot＠sgcib.com 15 Aug '07

15 Aug '07

Hi, I'd like to create a pipeline composed of filters that have different input and output character type. For example: file -> | Source | -> char -> | F1 | -> message -> | F2 | where F1 and F2 are input filters. F1 can be kind of a parser that would cut the stream into messages. The thing is that I could always rewrite a file_source but I think it's not a good design. What would you suggest? Thanks, ____________________________ Frederic MAYOT Société Générale - Equity IT 1221 Avenue of the Americas New York, NY 10020 +1 (212) 278-5558 +1 (917) 673-1339 ************************************************************************* This message and any attachments (the "message") are confidential and intended solely for the addressees. Any unauthorised use or dissemination is prohibited. E-mails are susceptible to alteration. Neither SOCIETE GENERALE nor any of its subsidiaries or affiliates shall be liable for the message if altered, changed or falsified. *************************************************************************

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Using cross-compiler to build the libraries
by Bruce Reid 15 Aug '07

15 Aug '07

I have been able to build (and link with) the libraries using the native gcc compiler on my linux-x86 platform, but have been unable to find a way to force the build process to use something like: /path/to/my/cross_compiler/for/linux-ppc/gcc Can someone please advise me in the proper way to build the libs with an absolute path to my cross compiler? Thanks very much for any help, Bruce CONFIDENTIALITY NOTICE: This email, together with any attachments, is intended only for use by Aristos Logic Corporation and the individual(s) to which it is addressed and may contain information that is privileged, confidential or exempt from disclosure. If you are not the intended recipient, you are hereby notified that any dissemination, distribution, or copying of this email, or any attachment, is strictly prohibited. If you have received this email in error, please notify Aristos Logic Corporation by sending an email to sysadm(a)aristoslogic.com and delete this email, along with any attachments, from your computer. Thank you.

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boost filesystem undefined reference...
by chun ping wang 15 Aug '07

15 Aug '07

./myfile/lib/libmy.a(my.o): In function `ZN4My6My_t4initERKNS0_10Settings_tE': C:/Boost/include/boost-1_34_1/boost/filesystem/path.hpp:302: undefined reference to `boost::filesystem::detail::status_api(std::string const&, unsigned int&)' ./myfile/lib/libmy.a(my.o): In function `_tcf_0': C:/CPW/cs_classes/./myfile/include/myerror.h:186: undefined reference to `boost::filesystem::detail::get_current_path_api(std::string&)' i build boost linking to a built boost filesystem file using mingw 3.4.5 including option. -l"boost_filesystem-mgw34-1_34_1" this is line 302 of path.hpp "const external_string_type external_file_string() const { return Traits::to_external( *this, file_string() ); }" "

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