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Is boost::asio::ip::tcp::iostream thread safe?
by boost 10 May '12

10 May '12

hi all, I use ip::tcp::iostream but I don't know if it is thread safe, and I cannot find the answer in boost document. I read from ip::tcp::iostream in the receiver thread, and send request in another thread. Now I protected the stream with a mutex. But the problem is that, if I do not send request, the server will not response, and the receiver will block on read with lock, and the sender cannot hold the lock and cannot send the request, deadlock. Is there anyone know that? Please kindly give me an answer. Best Regards Zhanwei Wang

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[Boost users] [ublas] Type conversion warning with ublas::bounded_vector
by Matija Kecman 10 May '12

10 May '12

Hi Boost users! Is there a way for boost.ublas to warn of type conversions with ublas::bounded_vector's? I'm using this library for scientific computations and I came across this problem, I have quite a large code so I would be useful to know if this mistake occurs elsewhere. Here is a code example: int main() { double d = M_PI; unsigned u = d; cout << "d = " << d << endl; cout << "u = " << u << endl; bounded_vector<double,3> dVec = ublas::scalar_vector<double>(3,M_PI); bounded_vector<unsigned,3> uVec = dVec; // ATTENTION: type conversion! cout << "dVec = " << dVec << endl; cout << "uVec = " << uVec << endl; return 0; } When I compile this using g++ 4.6.1: g++ -g3 -Wall -Wextra -ansi -pedantic -Wconversion -std=c++0x test.cpp -o test I get the following warnings: test.cpp: In function ‘int main()’: test.cpp:11:22: warning: conversion to ‘unsigned int’ from ‘double’ may alter its value [-Wconversion] Program output: $ ./test d = 3.14159 u = 3 dVec = [3](3.14159,3.14159,3.14159) uVec = [3](3,3,3) The compiler produced a warning for the conversion of the scalars but there was no warning for the ublas conversion, is there a way of having the compiler write a warning in that case? -Wconversion or any of the other options don't do this. Best, Matija

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[Boost users] [Program_options] Is Boost.Program_options available as a header?
by Matija Kecman 10 May '12

10 May '12

Hi Boost users, I'm quite new to boost. I have written a program using the Boost Program Options library. In order to compile it I have to link with the boost program options library. I would like to run my program on a computer which only has access to boost headers. I was wondering if the program options library is available as a header only? If not, it would be interesting to know the reason for that :) Best, Matija

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time variant uuid
by Victor Whiskey Yankee 10 May '12

10 May '12

Hello List, How can I create uuids so that the first one compares less than the next one.. something like this: boost::uuids::t1 = boost::uuids::random_generator()(); boost::uuids::t2 = boost::uuids::random_generator()(); BOOST_REQUIRE (t1 < t2); I don't see how to replace random_generator() with a time-based variant, if that even makes sense. If this can be done, then is there a way to extract the date+time from it? Thanks, Vic

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[Pool] Why is pool allocator slower than ordinary allocator?
by Mr.C64 10 May '12

10 May '12

Please see this thread on StackOverflow: http://tinyurl.com/chh4yxj Thanks.

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[Statechart] Pass variable parameter to Player ctor?
by Dick Bridges 10 May '12

10 May '12

In the PingPong example, I'm trying to pass a std::string variable to the Player ctor through the fifo_schedular<>create_processor<>() in main(). No joy. Error: no matching signature. I'm missing something obvious. I've stared at that first override in the boost header and tried everything I could think of. Dead give away that I don't understand: I'm "trying" things. %>[ I'd sure appreciate it if someone could point me in the right direction. Are there async examples that pass variables through create_processor() to the ctorS? Thanks for taking the time to read this, Dick

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[build] How can I change how the linker is called?
by Daryle Walker 10 May '12

10 May '12

This is for my PowerPC Tiger Mac system. I've installed GCC 4.7 fromMacPorts on it. I have it set in C++11 mode. Yesterday, I wrote on the list that I couldn't get the example file torun in my new trial project. (It's at<https://github.com/CTMacUser/Unionize>.) As soon as I added acompile-fail test and the corresponding line to Jamfile, everything worked! Sort of. The compile-fail test fails as expected (at compile-time).The example file still doesn't run due to a linking error I've seen before: //========================================[daryle@daryle-walkers-emac:test]$ b2 toolset=gcc-4.7...found 30 targets......updating 14 targets...common.mkdir bincommon.mkdir bin/super_union_basics.testcommon.mkdir bin/super_union_basics.test/gcc-4.7common.mkdir bin/super_union_basics.test/gcc-4.7/debuggcc.compile.c++ bin/super_union_basics.test/gcc-4.7/debug/super_union_basics.ogcc.link bin/super_union_basics.test/gcc-4.7/debug/super_union_basicsld: unknown option: --start-groupcollect2: error: ld returned 1 exit status "g++-mp-4.7" -o "bin/super_union_basics.test/gcc-4.7/debug/super_union_basics" -Wl,--start-group "bin/super_union_basics.test/gcc-4.7/debug/super_union_basics.o" -Wl,-Bstatic -Wl,-Bdynamic -Wl,--end-group -g ...failed gcc.link bin/super_union_basics.test/gcc-4.7/debug/super_union_basics......skipped <pbin/super_union_basics.test/gcc-4.7/debug>super_union_basics.run for lack of <pbin/super_union_basics.test/gcc-4.7/debug>super_union_basics...common.mkdir bin/super_union_fail_test.testcommon.mkdir bin/super_union_fail_test.test/gcc-4.7common.mkdir bin/super_union_fail_test.test/gcc-4.7/debuggcc.compile.c++ bin/super_union_fail_test.test/gcc-4.7/debug/super_union_fail_test.oIn file included from super_union_fail_test.cpp:9:0://======================================== Now "ld" points to a version of ld64 from MacPorts, but that error hasshown up before this. I don't think my versions of "ld" have"--start-group" or "--end-group" options. What should they be instead,and where do I make these changes? (Even if no one here can answer thefirst part, they should be able to answer the second. That's where I'llmake the changes if I have to ask about the first part elsewhere.) Oh, I've uploaded the version of the project used here. Its SHA ID is"535241c3f13a9488bd845549ce3b1cf661ffcbac". (It's the latest as of this writing.) Daryle W.

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filesystem V3 path::normalize deprecated
by Shai Shasag 09 May '12

09 May '12

I have a question regarding the deprecated function path::normalize(). Before moving to V3 I used this function to resolve paths containing "..". For example: path myPath("/Dir_A/Dir_B/a.txt/.."); myPath->normalize(); now myPath is: "/Dir_A/Dir_B" How can this be done using V3 code? Thanks, Shai PS: Could not find in docs why this function was deprecated and what replacement available.

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c++ serial com connection
by Evaggelos Tsampazis 09 May '12

09 May '12

Hi! I would like to ask if I can use the boost libraries on the IDE environment of GodeGear RAD studio (C++ builder) 2009? I included the header file <boost/asio.hpp> but I got some compilation errors. I would like to use the boost libraries to make a connection to the mobile phone (via USB) to send and receive AT Commands to it. The asio part is the best boost solution for my case. Can anyone help to explain how to make boost libraries work in the environment I am working in? Thanks, Evaggelos

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[MSM] What's the easiest way to share data between states in a Boost.MSM state machine?
by B. Tommy Jensen 08 May '12

08 May '12

As the subject indicates, I'm trying to find the best way to share data between states in a MSM state machine. My first attempt has been to let each sub-machine and state inherit from a common base class, e.g.: struct MyStateMachine_ : public msm::front::state_machine_def<MyStateMachine_,CommonBaseClass> My idea is to add a reference to some shared data in the base class, making it easy to access the shared data from any state. The shared data reference must be passed to the base class. Questions: 1. Is it possible to pass constructor parameters to the common base class' constructor? I have tried different options without success, it seems that the default constructor with no arguments is the only option. 2. If 1. is not possible, what is the best way to initialize the shared property correctly? For example an easy method to iterate over all defined states? (not only the active ones). I have tried to iterate over all states with get_state_by_id, but this method does not enter sub-machines' states. 3. In general, what is the preferred way of implementing shared data between state classes in Boost.MSM? It would have been natural to store the data in the root state, but I can't see that there is an easy way to get access to the root FSM. (only the "nearest parent" FSM in the hierarchy is passed to the various event handler methods). Regards, Tommy

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asio async_read_some handler called but has bad data
by Matt Fair 08 May '12

08 May '12

Hello, I have client/server code similar to the chat server, but I am using async_read_some/async_write_some. I am having a problem with my client when the server sends a bunch of data to it at one time. What happens is that it works for a while then readComplete is called with a full buffer and no error set, but my buffer has garbage and eventually causes my socket to crash. I wanted to check with everyone to see if they have seen this problem before, and if there is anything glaring that I'm doing wrong here with boost::asio. I noticed that in the http server it is using shared_from_this, is this necessary? If the server is sending the client data with async_write faster than I can processes it with async_read, could it cause some buffer overrun? Thanks, Matt My buffer is defined as a private array: static const unsigned int m_maxReadLength = 1024; // maximum amount of data to read in one operation char m_readBuffer[m_maxReadLength]; The client starts to read the socket with: void TCPSocket::readStart() { if(isOpen()) { // Start an asynchronous read and call read_complete when it completes or fails m_pSocket->async_read_some( boost::asio::buffer(m_readBuffer, m_maxReadLength), boost::bind( &TCPSocket::readComplete, this, boost::asio::placeholders::error, boost::asio::placeholders::bytes_transferred)); } } My readComplete method is: void TCPSocket::readComplete(const boost::system::error_code& error, size_t bytes_transferred) { // the asynchronous read operation has now completed or failed and returned an error if(!error && bytes_transferred <= m_maxReadLength) { //convert to string const string buffer(&m_readBuffer[0], &m_readBuffer[bytes_transferred]); //buffer eventually becomes junk ..... } else { //handle error } readStart(); //read some more data }

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boost graph: isomorphism SIGSEGV
by Vömel Christof (vome) 08 May '12

08 May '12

Hi, when testing boost graph 1.46 isomorphism on two graphs of size 11869 on x86_64-suse-linux, g++ 4.6.2, compiled at various levels of optimization, I consistently get the following error. (on very small graphs, everything seems to work) Could this be due to a problem of recursion/stack size due to the size of the graph? Up to what size of graph is the isomorphism program sure to work? Thanks, Chris Program received signal SIGSEGV, Segmentation fault. 0x00000000004099a6 in boost::iterator_core_access::equal<boost::detail::out_edge_iter<__gnu_cxx::__normal_iterator<boost::detail::sei_<unsigned long, std::_List_iterator<boost::list_edge<unsigned long, boost::no_property> >, boost::no_property>*, std::vector<boost::detail::sei_<unsigned long, std::_List_iterator<boost::list_edge<unsigned long, boost::no_property> >, boost::no_property>, std::allocator<boost::detail::sei_<unsigned long, std::_List_iterator<boost::list_edge<unsigned long, boost::no_property> >, boost::no_property> > > >, unsigned long, boost::detail::edge_desc_impl<boost::undirected_tag, unsigned long>, long>, boost::detail::out_edge_iter<__gnu_cxx::__normal_iterator<boost::detail::sei_<unsigned long, std::_List_iterator<boost::list_edge<unsigned long, boost::no_property> >, boost::no_property>*, std::vector<boost::detail::sei_<unsigned long, std::_List_iterator<boost::list_edge<unsigned long, boost::no_property> >, boost::no_property>, std::allocator<boost::detail::sei_<unsigned long, std::_List_iterator<boost::list_edge<unsigned long, boost::no_property> >, boost::no_property> > > >, unsigned long, boost::detail::edge_desc_impl<boost::undirected_tag, unsigned long>, long> > (f1=..., f2=...) at /usr/include/boost/iterator/iterator_facade.hpp:535 535 return f1.equal(f2);

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Aspen Meadows Resort suite available for up to 4 nights of C++Now Conference
by Pdruck 08 May '12

08 May '12

Hi. I reserved a suite at Aspen Meadows Resort for 4 nights, for the C++Now conference; Sunday night, May 13 – Wed night, May 16, leaving Thurs. May 17. But due to last minute pressing events in the office, I have to cancel my registration. Propose to switch my reservation to whomever might be attending. Win-win. I don’t lose a heft cancellation fee. You get a beautiful suite (having been there previously) and conveniently located to the conference at Physics Center. Regards. Phil

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Re: [Boost-users] Updating filesystem to V3 (boost 1.49) - normalize deprecated
by Shai Shasag 08 May '12

08 May '12

Thanks, Lars I defined the macros only for my code and now everything compiles. I have a question regarding the deprecated function path::normalize(). Before moving to V3 I used this function to resolve paths containing "..". For example: path myPath("/Dir_A/Dir_B/a.txt/.."); myPath->normalize(); now myPath is: "/Dir_A/Dir_B" Can this be done using V3 code? Thanks, Shai

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Use boost::object_pool can not quit clearly. Am I misusing?
by 文凯 08 May '12

08 May '12

I use boost::object_pool in my program, but I found some problems, it can not quit. Below is the code. Don't suggest me use boost::pool. The boost::pool is no problem, just discuss the boost::object_pool. Could anybody help me? #include <iostream> #include <boost/pool/object_pool.hpp> int main(void) { boost::object_pool<int> p; int count = 1000*1000; int** pv = new int*[count]; for (int i = 0; i < count; i++) pv[i] = p.construct(); for (int i = 0; i < count; i++) p.destroy(pv[i]); delete [] pv; return 0; } This program can not quit normally. Why? http://stackoverflow.com/questions/10491649/use-boostobject-pool-can-not-qu… -- Cheers & KaiWen

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Technical Question
by Erwin C. 07 May '12

07 May '12

Hey Boost! I plan on using Boost for the first time for our school project during our third year. I am using Visual Studio 2010 (windows) as the only member in the project to use Boost with. I added the root of the boost folder as additional include directory which turns out to be the correct way for the includes to work. But when i build i get the following error. 1>LINK : fatal error LNK1104: cannot open file 'libboost_system-vc100-mt-gd-1_49.lib' I searched thoroughly on google but i did not know what to do with the information... Kind Regards. Erwin

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Forwarding ctor calls in fusion sequence
by Joel Falcou 07 May '12

07 May '12

Say I have a fusion vector of different types with a constructor taking an int. eg: fusion::vector< std::vector<double>, std::vector<int> > and I have such a type as a member of a class foo. Now class foo has a constructor taking an int and I want to forward this parameter to all constructor of my fusion sequence member. Is there a C++03 way to do this with minimal amount of copying ?

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[asio] Connection not ending
by Markus Bonk 07 May '12

07 May '12

Hi, I have a server and connection originally based on the http server 3 example. I am calling io_service::stop which results in the server run() being ended. Currently, though, I am not seeing the connection being ended, or the destructor being called. I interpret this as being because the shared_ptr to the connection instance is still being held by the async_read_some() callback functor. I was expecting the stop() to result in the async_read_some() exiting/aborting. Should it or do I need to do something specific to get rid of the connection? I am using boost 1_44 Markus ________________________________ Markus Bonk Senior Software Engineer [cid:imagee211e8.GIF@21ba809e.4bbea53b] 3Dconnexion GmbH Clarita-Bernhard-Str. 18 81249 München Germany Tel: +49 (89) 897 45 42 - 70 Fax: +49 (89) 897 45 42 - 50 markus_bonk(a)3dconnexion.com<mailto:markus_bonk@3dconnexion.com> Kennen Sie schon die NEUE SpaceMouse Pro? Hier klicken um mehr zu erfahren!<http://www.3dconnexion.de/products/spacemousepro.html?3dxcp=signature_mail> Geschäftsführer: Antonio Pascucci Sitz der Gesellschaft: München Registergericht: München HRB 99232

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boost::function and cross dll call issue
by ariasgore＠gmx.de 07 May '12

07 May '12

Hello, I have a weird access violation when using boost::function which is passed from one DLL to another. At work we use an engine that loads libraries at runtime. One of those libraries provides a class, that looks like that: class CLib { public: LIB_API CLib(void); typedef boost::function<void ()> Func; LIB_API void virtual Invoke(Func * func); }; Another library tries to make use of this lib by void freedummy() { int x = 0; } CLib::Func f = freedummy; f(); // testinvoke locally c.Invoke(&f); // passing to dll The invocation fails hard with Visual Studio 2008 SP1 (Windows 7 64bit, application as 32 bit) when passing to the other dll. The result is a call to a function address that points to nomans-land (c.Invoke()), whereas the direct f() call invokes the freedummy correctly. I have tried to create a very basic reproducer for this case and I could not make it crash. I tried to track down the execution of freedummy in the disassembler. The f-Pointer remains the same all the time but when boost::function0<void>::operator()() gets called on the lib the ptr to f remains correct but the inner function_ptr pointing to freedummy gets corrupted and pointing into garbage. Since I could NOT reproduce it with a simple test setup and I actually am not very sure why this fails I am a bit out of ideas. Can there be somehow a misalignment or different assembler (The dlls may have been compiled with different settings, not sure). I just remembered that this line: vtable_type* get_vtable() const { return reinterpret_cast<vtable_type*>( reinterpret_cast<std::size_t>(vtable) & ~static_cast<size_t>(0x01)); } (in function_template.hpp on 678) looked different in the disassembler when called f() in the main executable compared to the invocation in CLib in the external dll. Can I somehow get a better grip on what's happening? My assembler is not that strong that I could understand all those calls when journeying down the boost call stack. Any hint appreciated, Sam -- Empfehlen Sie GMX DSL Ihren Freunden und Bekannten und wir belohnen Sie mit bis zu 50,- Euro! https://freundschaftswerbung.gmx.de

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Using boost interprocess features from inside Class member functions
by Achuth Sankar 06 May '12

06 May '12

Hi All Am facing a lot of issue while using interprocess features inside my class file. I am pasting my class file below: class MyClass{ Ref* ref; public: MyClass(); void initializeBuffers(); void processMessage(); ~MyClass(); }; void MyClass::createBuffer() { shared_memory_object::remove("test"); shared_memory_object shm(open_or_create, infoBufferName, read_write); shm.truncate(sizeof(ServerDetails)); mapped_region region(shm, read_write); void* addr = region.get_address(); ref=new (addr) Ref; ref->value=50; } void MyClass::processMessage() { printf("%d",ref->value); //I get a segmentation fault in here. } int main() { MyClass c(); c.createBuffer(); c.processMessage(); } When I execute this I am getting segmentation exception. If I merge processMessage and createBuffer under same function it starts working. But if in any case I change the function signature to have an argument again this issue starts. Am not sure if I am doing some thing wrong above. Please do help me on this. Error I get is: Program received signal SIGSEGV, Segmentation fault. 0x77d41df8 in ntdll!RtlGetCompressionWorkSpaceSize () from C:\Windows\system32\ntdll.dll -- Achu

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Updating filesystem to V3 (boost 1.49)
by Shai Shasag 06 May '12

06 May '12

I'm in the process of updating my code to use filesystem V3. I replaced all the V2 deprecated functions with V3 calls. I defined the macros: BOOST_FILESYSTEM_VERSION=3 BOOST_FILESYSTEM_NO_DEPRECATED When compiling the file libs/filesystem/v3/src/path.cpp I get the following error: #error both BOOST_FILESYSTEM_DEPRECATED and BOOST_FILESYSTEM_NO_DEPRECATED are defined The reason for this error is that in filesystem/v3/config.hpp has the following: // BOOST_FILESYSTEM_DEPRECATED needed for source compiles # ifdef BOOST_FILESYSTEM_SOURCE # define BOOST_FILESYSTEM_DEPRECATED # endif So i'm puzzled as to why BOOST_FILESYSTEM_DEPRECATED is forced when compiling path.cpp? And how can I avoid theses erros when compiling filesystem V3? Thanks Shai Boost version: 1.49 Compiler: gcc version 4.2.1, Xcode 3.2.5 on Mac OS 10.6.8

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random number generators seeding with 0 and 1
by Nelis Willers 05 May '12

05 May '12

Dear Boost Users While testing my RNG I noticed that the use of seed value 0 yields the same results as using a seed value of 1. It seems that this is the specified behaviour for rand() in the C runtime library: http://stackoverflow.com/questions/8049556/whats-the-difference-between-sra… I could find no reference to this in my (oldish) draft C++0x spec. Also no mention in the boost random doc page. I tried to unravel the random include files, but got lost. Is this behaviour required by the specification or just following tradition? More important, is this behaviour guaranteed in all libraries? thanks! nelis

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Building boost to NOT USE built-in Visual Studio 2010 TR1 random
by Nelis Willers 05 May '12

05 May '12

Dear Boost-Users boost 1.49.0 and Visual Studio 2010 / Visual Studio 2005 / & g++ 4.6.3 on (Win7 and Ubuntu 12.04) Build boost libs locally, using the local compilers. The objective is to get exactly the same random number generator behaviour for the same application built with VS2005, VS2010 and Gnu compilers. Building the same code, I see the* same normal & uniform* results under gnu and VS2005 builds (presumably boost random is used under VS2005). Building the same code, I see the different *normal results* under gnu and VS2010 builds (presumably the native VC lib is used under VS2010). So I would like to use (at least) boost's random library instead of the native Visual C++ 2010 library. >From boost docs I learned that it is possible to set up the boost config files such as to use/not use the native compiler/library TR1 implementation: http://www.boost.org/doc/libs/1_49_0/libs/config/doc/html/index.html#boost_… http://www.boost.org/doc/libs/1_49_0/libs/config/doc/html/boost_config/boos… http://www.boost.org/doc/libs/1_49_0/doc/html/boost_tr1/usage.html#boost_tr… I cannot however, figure out how to do this from the above docs. BOOST_HAS_TR1_RANDOM comes into it, but I fail to get the big picture. Can anybody please advise? thanks in advance! nelis

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Bimap compare function
by Tyler Conant 05 May '12

05 May '12

I noticed that the comparator for a bimap can only be a Functor Type. It does not appear that I can pass a function object or a function pointer, as a STL Set would allow. Is this correct or did I miss something. For my application I could really use the ability to pass in comparator which is decided at runtime. Does anyone have any suggestions on a work around?

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[mpl] Why no wrapper for pointers as non-type template parameters?
by Philipp Moeller 04 May '12

04 May '12

I'm a little surprised that the MPL does not offer a wrapper for pointers as constants. They sometimes come in handy to specify lists to different callable objects. Something along the lines of: template<typename T, T N> struct ptr_wrap { static const T value; typedef ptr_wrap<T, N> type; typedef T value_type; }; template<typename T, T N> typename ptr_wrap<T, N>::value_type const ptr_wrap<T, N>::value = N; already does the job for me, but it could possibly be enhanced with a helper to use the correct syntax for pointers to member. Could this be an addition to the library or is there a better way? Cheers, Philipp Moeller

1 0

[Serialization] Linker errors issue with using binary_wiarchive.hpp and binary_woarchive.hpp
by Lord Metritutus Merkwurdichliebe 04 May '12

04 May '12

Hello there, I've never used one of these Mailing List conversations before so I apologise for any mistakes. To the point: I'm having issues trying to get the wide character version of Boost's serialization libaries working. When I attempt to compile the result is a multitude of Linker errors. After Googling failed to turn up anything I posted the question on Stack Overflow, where a reply suggested there may be 'a bug in Boost.Serialization'. Stack Overflow features nice syntax highlighting so it is easy to see the code, I pieced it together from other normal character examples: http://stackoverflow.com/questions/10439984/serialization-example-of-boost-… If there is a rule against posting external links, I apologise. Or if people want me to paste the code directly in to an email for this mailing list I will do so. The Stack Overflow question was originally based on my thought that I had made a mistake in my code. If this IS the case then I do apologise, and I would appreciate knowing just where I've gone wrong. Regards.

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Re: [Boost-users] [Serialization] Linker errors issue with using binary_wiarchive.hpp and binary_woarchive.hpp
by Lord Metritutus Merkwurdichliebe 04 May '12

04 May '12

I believe I was asked this in the Stack Overflow question I linked as well. Assuming that all the .lib files in the stage/lib folders are the built libraries (I could be wrong so please correct me if that is the case), and assuming that libboost_serialization-vc100-mt-1_47.lib or libboost_serialization-vc100-mt-gd-1_47.lib are the libraries I need, I believe that both of the latter things you mentioned are satisfied. Regards. From: bryan.bagnall(a)navy.mil To: boost-users(a)lists.boost.org Date: Thu, 3 May 2012 18:36:03 -0700 Subject: Re: [Boost-users] [Serialization] Linker errors issue with using binary_wiarchive.hpp and binary_woarchive.hpp From: http://www.boost.org/doc/libs/ It looks like the serialization library requires you to build boost (it is not header only) Instructions can be found here: http://www.boost.org/doc/libs/1_49_0/more/getting_started/windows.html http://www.boost.org/doc/libs/1_49_0/more/getting_started/unix-variants.html If you have built boost already, make sure to include the boost libs in your linker path. Regards -----Original Message----- From: boost-users-bounces(a)lists.boost.org [mailto:boost-users-bounces@lists.boost.org] On Behalf Of Lord Metritutus Merkwurdichliebe Sent: Thursday, May 03, 2012 5:09 PM To: boost-users(a)lists.boost.org Subject: [Boost-users] [Serialization] Linker errors issue with using binary_wiarchive.hpp and binary_woarchive.hpp Hello there, I've never used one of these Mailing List conversations before so I apologise for any mistakes. To the point: I'm having issues trying to get the wide character version of Boost's serialization libaries working. When I attempt to compile the result is a multitude of Linker errors. After Googling failed to turn up anything I posted the question on Stack Overflow, where a reply suggested there may be 'a bug in Boost.Serialization'. Stack Overflow features nice syntax highlighting so it is easy to see the code, I pieced it together from other normal character examples: http://stackoverflow.com/questions/10439984/serialization-example-of-boost-a rchive-binary-woarchive-hpp-and-or-boost-archive <blockedhttp://stackoverflow.com/questions/10439984/serialization-example-of -boost-archive-binary-woarchive-hpp-and-or-boost-archive> If there is a rule against posting external links, I apologise. Or if people want me to paste the code directly in to an email for this mailing list I will do so. The Stack Overflow question was originally based on my thought that I had made a mistake in my code. If this IS the case then I do apologise, and I would appreciate knowing just where I've gone wrong. Regards. _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users

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[Polygon] Multiple Holes
by Bagnall, Bryan D CIV SPAWARSYSCEN-PACIFIC, 56220 04 May '12

04 May '12

Hello, I'm trying to use Boost::polygon to do Boolean operations in my project. My project uses contours that I'm grabbing with OpenCV, processing with Boost::polygon, then writing out to an ESRI shapefile. OpenCV can give me a list of contours within contours within contours...etc, and shapefiles can be written out this way (see link for picture http://icode-mda.googlecode.com/svn/trunk/examples/09_KMLshp/shapefilesWithH oles/results/blobsWithHoles.png ) I haven't been able to jam all of the data in a single polygon_with_holes_data polygon. Is it true that boost::polygon::polygon_with_holes_data can only have an exterior contour and multiple holes, but no contours inside of the hole? In other words, could a single boost polygon support a continent with a lake, with an island, with a pond, with a small island... ? Is there another type that would support this? Maybe the Geometry library? My current work around is to have (1)the continent with a lake as one polygon, (2)the island with a pond as another,(3)the small island as another... Thanks, Bryan

1 0

[Serialization] Issues with C++/CX in MSVC 11
by Brent Lewis 04 May '12

04 May '12

In porting a project from iOS to Windows 8, I'm continuing to use Boost 1.49 to save the state of the program. I'm having what seems to be problems with a compiler bug. I'm wondering if anyone has found a workaround? Thought it's probably not necessary, I'll explain exactly what I'm seeing in detail in case it's helpful. If one creates a new Visual Studio project from the C++ Metro style Direct3D application template, simply adding these lines to the main function works just fine: std::stringstream memStream(std::ios_base::binary | std::ios_base::in | std::ios_base::out); boost::archive::binary_oarchive oa(memStream); However, when I add the rest of the project files (even if I don't instantiate any of the classes - just adding the modules does it), the two same lines in the main function crash. I eliminated all the code from the modules that refer to serialization and archive classes, because I noticed that there was a lot of static initialization of singletons of templated archive classes. Even with minimal static initializers, still, the code fails to run. Closest thing I can tell is that the compiler is not correctly translating the this pointer when moving from a class's initializers into a superclasse's constructor when multiple inheritance is involved (and perhaps lots of templating is required too). To be specific, in one specific run of the application (note that I've removed the template parameters for brevity): Inside binary_oarchive_impl ctor, the this pointer is: 0x0091fcb8 moving into its superclass constructor, basic_binary_oprimitive, the this pointer is: 0x0091fcc1 That would suggest that the superclass is 9 bytes into the derived class, however: back inside the binary_oarchive_impl ctor, using the debugger: (boost::archive::basic_binary_oprimitive*)this : 0x0091fcc4 offsetof(basic_binary_oprimitive, m_sb) = 0 (offsets retrieved by inspecting/altering memory, since you can't get the offset of a reference type) offsetof(binary_oarchive_impl, m_sb) = 12 Which clearly indicates that the superclass is 12 bytes into the derived class. In the superclass, it initializes m_sb - which is a reference to the stream buffer the archive writes to. Stepping back out of the superclass constructor, back into the derived class constructor, m_sb points to the wrong memory, of course. Has anyone else experience this with C++/CX? Is there an existing bug report? We've got a Microsoft contact that's helping us iron out issues. Does anyone know a concise repro that'll help MS solve this problem faster? Thanks for any information.

2 2

[Range] Weak concept assertions.
by Robert Jones 03 May '12

03 May '12

Here's a snippet from boost/range/algorithm_ext/push_back.hpp... namespace boost { namespace range { template< class Container, class Range > inline Container& push_back( Container& on, const Range& from ) { BOOST_RANGE_CONCEPT_ASSERT(( SinglePassRangeConcept<Container> )); BOOST_RANGE_CONCEPT_ASSERT(( SinglePassRangeConcept<const Range> )); BOOST_ASSERT( (void*)&on != (void*)&from && "cannot copy from a container to itself" ); on.insert( on.end(), boost::begin(from), boost::end(from) ); return on; } } // namespace range using range::push_back; } // namespace boost Shouldn't the first concept assert be asserting that 'Container' is in fact a container, not a range? Thx - Rob.

1 0

[asio] documentation example, bind semantics
by John M. Dlugosz 03 May '12

03 May '12

In boost_asio/tutorial/tutdaytime3.html, the code shown is: void handle_accept(tcp_connection::pointer new_connection, const boost::system::error_code& error) { and is called via a function object: boost::bind(&tcp_server::handle_accept, this, new_connection, boost::asio::placeholders::error) I get after my coworkers I'm mentoring in the area of C++ skills to pass smart pointers by const-ref not by value, since the atomic inc/dec is very costly. I believe that a boost::function (and now std::function) will hold the object by value even if the function being bound declares it as reference, and the INVOKE phase will bind the parameter to the stored copy in the function object. So handle_accept can and should be declared as using a const tcp_connection::pointer& as well, right? Is there any reason not to? —John

2 1

[Boost.Integer] On Win32, boost::uint_t<65>::fast has 64 bits?
by Scott Meyers 03 May '12

03 May '12

The type yielded by boost::uint_t<N>::fast seems pretty clear: "The easiest-to-manipulate, built-in, unsigned integral type with at least N bits." But when I run the following program, which prints the number of bits in the type returned by boost::uint_t<65>::fast (i.e., a type with at least 65 bits), I get 64. #include <iostream> #include <climits> #include <boost/integer.hpp> int main() { std::cout << "boost::uint_t<65>::fast has " << CHAR_BIT * sizeof(boost::uint_t<65>::fast) << " bits\n"; } I get the same results with VC10, VC11 beta, and gcc 4.7 on Win32 with Boost 1.49. I must be doing something wrong, right? But what? Thanks, Scott

5 10

Fusion warning cleanup
by Belcourt, Kenneth 03 May '12

03 May '12

Hi, Could these (and other) auto generated headers be emitted so they don't trigger these sorts of warnings? We get these warnings with multiple compilers. Thanks. -- Noel Belcourt CC-1 crayc++: WARNING File = /scratch1/kbelco/boost/boost/status/../boost/fusion/tuple/detail/preprocessed/tuple_fwd.hpp, Line = 21 The source file does not end with a new-line character. #endif ^ CC-1 crayc++: WARNING File = /scratch1/kbelco/boost/boost/status/../boost/fusion/tuple/detail/preprocessed/make_tuple.hpp, Line = 21 The source file does not end with a new-line character. #endif ^ CC-1 crayc++: WARNING File = /scratch1/kbelco/boost/boost/status/../boost/fusion/tuple/detail/preprocessed/tuple_tie.hpp, Line = 21 The source file does not end with a new-line character. #endif ^

2 1

[Range] Predicate type checking.
by Robert Jones 02 May '12

02 May '12

I'm pretty sure I'm have a 'Doh!' moment here, but why does this compile? Surely the last line of main is gibberish; the value type of m is pair, not S, so int_from_S is not a valid function? #include <boost/range.hpp> #include <boost/range/adaptor/transformed.hpp> #include <map> struct S { S( ) { } int i; }; int int_from_S( S s ) { return s.i; } int main( ) { std::map<unsigned, S> m; m[0]=S(); m | boost::adaptors::transformed(int_from_S); } Thx, - Rob.

2 1

config. how to check if std::shared_ptr & std::scoped_ptr availability?
by niXman 02 May '12

02 May '12

Hello! I need to check if std::shred_ptr & std::scoped_ptr availability. I read boost.config and found: http://www.boost.org/doc/libs/1_49_0/libs/config/doc/html/boost_config/boos… But in this list don't exist macro that I need. Ideas? Thanks. -- Regards, niXman

3 4

multiarray sub_array
by Petros 01 May '12

01 May '12

Hi, I want to be able to create an array view on a subset of a multi_array(MA)’s dimensions. So, say I have a MA of dimension M and I want to choose N (N <M) dimensions of it which I put on a boost::array. Say, I want to keep the entire range for each dimension. Is there a way to do this in a general fashion, i.e. w/out the use of the subscript operator on the indices object ? The documentation mentions something like : typedef boost::multi_array< double, 3 > Grid3D; typedef Grid3D::size_type size_type; typedef Grid3D::index index; typedef Grid3D::index_range index_range; typedef Grid3D::array_view<2>::type Slice2D; index_range r1; //( 0, iMax); index_range r3; //( 0, kMax); Grid3D::index_gen indices; Slice2D sliceJ2 = grid[indices [r1] [2] [r3] ]; but this is not sufficient for a generic construction. And also, what is the difference between array_view and subarray ? Thank you very much in advance, Petros

1 0

fatal error C1001 with VS2010, boost 1.49, and shared_ptr.hpp
by Phillip Hellewell 01 May '12

01 May '12

I'm upgrading to boost 1.49 and getting this fatal error while compiling a source file that uses shared_ptr: 1>C:\mycomps\base\target\dependency\include\boost/smart_ptr/shared_ptr.hpp(362): fatal error C1001: An internal error has occurred in the compiler. 1> (compiler file 'msc1.cpp', line 1420) 1> To work around this problem, try simplifying or changing the program near the locations listed above. 1> Please choose the Technical Support command on the Visual C++ 1> Help menu, or open the Technical Support help file for more information Line 362 of shared_ptr.hpp is: shared_ptr( shared_ptr<Y> && r, typename boost::detail::sp_enable_if_convertible<Y,T>::type = boost::detail::sp_empty() ) Looks like the compiler is crashing with an access violation; any suggestions other than wait for a patch from Microsoft? I don't want to have to disable features like BOOST_HAS_RVALUE_REFS or BOOST_SP_NO_SP_CONVERTIBLE, but that may be my only choice :( Thanks, Phillip

2 3

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))); } }

3 2

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 ?

3 6

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

1 0

[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

2 4

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 >

1 0

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

1 0

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

1 0

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

2 2

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

2 4

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

4 5

date_time, g++-4.7.0, compile error
by List User 29 Apr '12

29 Apr '12

The following code gives compile error with g++-4.7.0 but compiles fine with g++-4.6. #include <iostream> #include <boost/date_time/local_time/local_time.hpp> using namespace std; int main(){ boost::posix_time::ptime time_t_epoch(boost::gregorian::date(1970,1,1)); cout << time_t_epoch << endl; return 0; } The following is the error message that is repeatedly seen (compiler outputs a lot of messages) /usr/include/boost/date_time/local_time/local_date_time.hpp:433:84: error: use of deleted function boost::shared_ptr<boost::date_time::time_zone_base<boost::posix_time::ptime, char> >::shared_ptr(const boost::shared_ptr<boost::date_time::time_zone_base<boost::posix_time::ptime, char> >&) I am using Ubuntu 12.04 and libboost-date-time1.46.1. Any suggestions? thanks suresh

2 2

[wserialization] serializing to a stringstream
by Sean Farrow 29 Apr '12

29 Apr '12

Hi: I'm using xml serialization and need to serialize to a string stream for encryption purposes. As I am using xml_woarchive, should I use wstringstream or just the normal stringstream? Does the wide version even exist? Essentially does the boost serialization library convert to narrow characters before serializing or not? Any help appreciated. Regards Sean.

2 1

How to send serialized data via boost::interprocess::message_queue
by Jens Saathoff 28 Apr '12

28 Apr '12

Hi! I'm working with message_queue and want to send a structure to receiver-app. How to serialize i correctly and how to receive it? Here's some sending code: Data data; > data.counter = 9; > data.money = 5.4; > //data.name = "Guten Tag"; > > std::stringstream os; // = new std::stringstream; > boost::archive::text_oarchive oa(os); > oa << data; > > ipc::message_queue::remove("mq_main"); > ipc::message_queue mq(ipc::create_only, "mq_main", 1, > sizeof(std::stringstream)); > mq.send(&os, sizeof(os), 0); I implemented the serializing code in the structure "Data" Add here's my code to receive: Data data; > std::stringstream is; // = new std::stringstream; > try > { > unsigned int priority; ///< The priority > ipc::message_queue::size_type recvd_size; > ipc::message_queue mq(ipc::open_only, "mq_main"); > > if(mq.try_receive(&is, sizeof(std::stringstream), recvd_size, > priority)) > { > boost::archive::text_iarchive ai(is); // CRASH > ai >> data; > } > //mq.receive(&is, sizeof(is), recvd_size, priority); > //mq.do_receive(ipc::message_queue_t::non_blocking, &is, > sizeof(is), recvd_size, priority); > > //boost::archive::text_iarchive * ai = new > boost::archive::text_iarchive(is); > > //*ai >> data; > > //data << ai; > //mq_recv->receive(&data, sizeof(data), recvd_size, priority); > > ipc::message_queue::remove("mq_main"); > //is.~basic_stringstream(); > } > catch(ipc::interprocess_exception &ex) > { > ipc::message_queue::remove("mq_main"); > std::cout << ex.what() << std::endl; > return; > } > The receiver-app crashes at boost::archive::text_iarchive ai(is). The error is: 0xC0000005: Access violation reading location 0x00f56a34. I really don't have a clue...pls help. Thank you very much :-)

1 0

serialize derived class object through boost::serialization
by breadbread1984 28 Apr '12

28 Apr '12

I want to serialize a derived class object through boost::serialization library. To test whether both the base and the derived class object have been serialized properly, I print message to the console when the serialize function is called. When the following code is compiled and runned, the message of serialize function for the base class object is not shown. Thus, the base class object is not serialized properly. Why the serialization is not done on the base class object? #include <cstdlib> #include <iostream> #include <fstream> #include <boost/serialization/version.hpp> #include <boost/serialization/export.hpp> #include <boost/archive/text_iarchive.hpp> #include <boost/archive/text_oarchive.hpp> #include <boost/shared_ptr.hpp> using namespace std; using namespace boost::archive; using boost::shared_ptr; class Base { friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, const unsigned int version); protected: int a; public: Base():a(0){} virtual ~Base(){} int geta() const {return a;} void seta(int aa) {a = aa;} }; template<class Archive> void Base::serialize(Archive & ar,const unsigned int version) { cout<<"serializing base class object"<<endl; ar & a; } class Derived : public Base { friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, const unsigned int version); protected: int b; public: Derived():Base(),b(0){} virtual ~Derived(){} int getb() const {return b;} void setb(int bb) {b = bb;} }; template<class Archive> void Derived::serialize(Archive & ar,const unsigned int version) { boost::serialization::base_object<Base>(*this); boost::serialization::void_cast_register<Derived,Base> ( static_cast<Derived*>(NULL), static_cast<Base*>(NULL) ); cout<<"serializing derived class object"<<endl; ar & b; } BOOST_CLASS_EXPORT_GUID(Derived,"Derived"); int main(int argc,char ** argv) { shared_ptr<Base> ptr(new Derived()); ptr->seta(4); Base * p = ptr.get(); Derived * pp = dynamic_cast<Derived*>(p); assert(pp); pp->setb(4); ofstream out("test.dat"); text_oarchive oa(out); oa << p; return EXIT_SUCCESS; }

2 1

undefined symbol: PyUnicodeUCS4_FromEncodedObject
by Dylan Dandelion 28 Apr '12

28 Apr '12

Is there a way to specify boost.python to be built with UCS2 instead of USC4? I am trying to build some libraries and ran into the following error: ImportError: /home/user/boost_1_49_0/stage/lib/libboost_python.so.1.49.0: undefined symbol: PyUnicodeUCS4_FromEncodedObject I am using a version of Python that seems to use only UCS2. # python Python 2.7.2 (default, Aug 24 2011, 22:13:27) [GCC 4.2.4 (Ubuntu 4.2.4-1ubuntu4)] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> import sys >>> print sys.maxunicode 65535 >From what I searched online so far, there are some suggestions to recompile Python with some flags to use UCS4, but that is not possible for me. Thanks!

1 0

Do boost run well on x64 platform with such warning?
by clive 27 Apr '12

27 Apr '12

Hi,my friends I have a stupid question Now i build boost 1.49 on x64 platform with vc2005 I find such many warnings: warning C4267: '=' : conversion from 'size_t' to 'unsigned int', possible loss of data or conversion from '_int64' to 'unsigned int', possible loss of data I want to make sure that these warnings really do lose data whether or not on x64 flatform. Put another way, could these warning be neglected or should i change the source code? Thanks

2 1

Re: [Boost-users] [xpressive][proto] Generates VS2010 C4714 in 1.49 but not in 1.48
by Lawry, Brian 27 Apr '12

27 Apr '12

Hi Eric. I replaced everything under ..\boost-1_49\boost\proto with the version from trunk yesterday, but I still get the warnings. "/DBOOST_FORCEINLINE=inline" works for me (performance is not an issue in my application). Thanks. Brian >Message: 1 >Date: Wed, 25 Apr 2012 12:44:46 -0700 >From: Eric Niebler <eric(a)boostpro.com> >To: boost-users(a)lists.boost.org >Subject: Re: [Boost-users] [xpressive][proto] Generates VS2010 C4714 > in 1.49 but not in 1.48 >Message-ID: <4F98542E.9080400(a)boostpro.com> >Content-Type: text/plain; charset=ISO-8859-1 >On 4/24/2012 11:33 PM, Eric Niebler wrote: >=> On 4/24/2012 2:48 PM, Lawry, Brian wrote: >>> I would be OK with suppressing the warning, but I haven't been able >>> to do so. Putting "#pragma warning(disable : 4714)" in my source >>> file and in boost/xpressive/detail/core/ sub_match_vector.hpp and in >>> boost/proto/transform/call.hpp does not suppress the warning. Using >>> the "disable specific warnings" compiler switch /wd4714 also does not >>> work. >I checked this and found that the warning can in fact be suppressed. I went through >proto's source files and suppressed it everywhere __forceinline is used. Your sample >code now compiles cleanly with /W4 with boost trunk. >Thanks for the report. >-- >Eric Niebler >BoostPro Computing >http://www.boostpro.com

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Re: [Boost-users] Do boost run well on x64 platform with such warning?
by John Drescher 27 Apr '12

27 Apr '12

> I have a stupid question > Now i build boost 1.49 on x64 platform with vc2005 > I find such many warnings: warning C4267: '=' : conversion from 'size_t' to > 'unsigned int', possible loss of data or conversion from '_int64' to > 'unsigned int', possible loss of data > I want to make sure that these warnings really do lose data whether or not > on x64 flatform. > Put another way, could these warning be neglected or should i change the > source code? Just neglect these warnings. These would only be a problem if size_t had > 4 billion elements. I certainly do not put that many elements into my structures yet! John

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[asio] Getting End of file on ssl::stream::shutdown
by Tak Sze 26 Apr '12

26 Apr '12

I have a very simple SSL client and server program that send messages back and forth using asio ssl stream. Both sides send a "no more message" message when they are done. Then they both call shutdown to shutdown the SSL connection. However, I kept getting "shutdown: End of file" from shutdown. Does anyone know why I am getting that? - Tak

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error: partial specialization after instantiation when using boost.atomic
by niXman 26 Apr '12

26 Apr '12

Hello! I try to use boost.atomic library[1] and when compiling this trivial code: > #include <iostream> > #include <boost/atomic.hpp> > int main() {} http://liveworkspace.org/code/3c355fc61db67d52266a66103bce325a and I get the following error: > boost/atomic/detail/integral-casts.hpp:155:7: > error: partial specialization of 'boost::detail::atomic::platform_atomic<T, 4u>' > after instantiation of 'boost::detail::atomic::platform_atomic<int>' I try to find the 'boost::detail::atomic::platform_atomic<int>' specialization, but couldn`t find it. Maybe someone faced with a similar error. Or maybe someone has an idea what kind of error is this, in fact? Thanks! [1] http://www.chaoticmind.net/~hcb/projects/boost.atomic/ -- Regards, niXman

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program_options, parse_config_file problems
by Andrew E Slaughter 26 Apr '12

26 Apr '12

Hello, I am attempting to parse configuration options from a file using Boost::program_options. I am following the example provided on the website (http://www.boost.org/doc/libs/1_49_0/doc/html/program_options/overview.html…) variables_map vm; store(parse_command_line(argc, argv, desc), vm); store(parse_config_file("example.cfg", desc), vm); notify(vm); I have included the following related to program_options: #include <boost/program_options.hpp> // Boost Program Options #include <boost/program_options/positional_options.hpp> #include <boost/program_options/parsers.hpp> I have the exact code as above in my program but receive the following error. The program works fine if I comment out the line with the parse_config_file line. Can someone please help me get this working. Thanks, Andrew --- COMPILER ERROR -------------------------- /home/slaughter/Documents/programs/source/common/user_options/user_options.cpp: In member function ‘void SlaughterCommon::User_options::apply_options(int, char**)’: /home/slaughter/Documents/programs/source/common/user_options/user_options.cpp:27:76: error: no matching function for call to ‘parse_config_file(const char [22], boost::program_options::options_description&, bool)’ /home/slaughter/Documents/programs/source/common/user_options/user_options.cpp:27:76: note: candidates are: /usr/include/boost/program_options/parsers.hpp:163:5: note: template<class charT> boost::program_options::basic_parsed_options<charT> boost::program_options::parse_config_file(std::basic_istream<charT>&, const boost::program_options::options_description&, bool) /usr/include/boost/program_options/parsers.hpp:176:5: note: template<class charT> boost::program_options::basic_parsed_options<charT> boost::program_options::parse_config_file(const char*, const boost::program_options::options_description&, bool) make[3]: *** [source/common/CMakeFiles/common.dir/user_options/user_options.cpp.o] Error 1 make[2]: *** [source/common/CMakeFiles/common.dir/all] Error 2 make[1]: *** [source/common/CMakeFiles/test_user_options.dir/rule] Error 2 make: *** [test_user_options] Error 2

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[xpressive][proto] Generates VS2010 C4714 in 1.49 but not in 1.48
by Lawry, Brian 25 Apr '12

25 Apr '12

The following code produces a C4714 warning in Visual Studio 2010 with Boost 1.49 but not 1.48: ------------------------------------------------------------------------ ---------------------------------------- #include "stdafx.h" #include <boost/xpressive/xpressive.hpp> void main() { using namespace boost::xpressive; sregex pat1 = "foo" >> +space >> "bar"; // OK in 1.48, C4714 in 1.49 sregex pat2 = "foo" >> +space >> "bar" >> +space; // OK in 1.48, C4714 in 1.49 sregex pat3 = "foo" >> +space; // OK in 1.48, OK in 1.49 sregex pat4 = "foo" >> +space >> +digit; // OK in 1.48, OK in 1.49 sregex pat5 = +space >> "foo" >> +space; // OK in 1.48, C4714 in 1.49 } ------------------------------------------------------------------------ ---------------------------------------- System: Compiler: Visual Studio 2010 SP1 [Microsoft (R) 32-bit C/C++ Optimizing Compiler Version 16.00.40219.01 for 80x86] Compiler warning level: /W4 OS: Windows 7 Professional 32-bit I would be OK with suppressing the warning, but I haven't been able to do so. Putting "#pragma warning(disable : 4714)" in my source file and in boost/xpressive/detail/core/ sub_match_vector.hpp and in boost/proto/transform/call.hpp does not suppress the warning. Using the "disable specific warnings" compiler switch /wd4714 also does not work. Complete warning text: ------------------------------------------------------------------------ ---------------------------------------- 1>c:\Boost\include\boost-1_49\boost/xpressive/detail/core/sub_match_vect or.hpp(115): warning C4714: function 'boost::xpressive::detail::static_xpression<Matcher,Next> boost::proto::call<PrimitiveTransform>::impl2<Expr,State,Data,B>::operat or ()(const boost::proto::exprns_::expr<Tag,Args,Arity> &,const boost::xpressive::detail::static_xpression<boost::xpressive::detail::str ing_matcher<Traits,ICase>,boost::xpressive::detail::static_xpression<Mat cher,boost::xpressive::detail::static_xpression<boost::xpressive::detail ::end_matcher,boost::xpressive::detail::no_next>>> &,boost::xpressive::detail::xpression_visitor<BidiIter,ICase,Traits> &) const' marked as __forceinline not inlined 1> with 1> [ 1> Matcher=boost::xpressive::detail::simple_repeat_matcher<boost::xpressive ::detail::static_xpression<boost::xpressive::detail::posix_charset_match er<traits_type>,boost::xpressive::detail::true_xpression>,boost::mpl::tr ue_>, 1> Next=boost::xpressive::detail::static_xpression<boost::xpressive::detail ::string_matcher<traits_type,boost::mpl::false_>,boost::xpressive::detai l::static_xpression<boost::xpressive::detail::simple_repeat_matcher<boos t::xpressive::detail::static_xpression<boost::xpressive::detail::posix_c harset_matcher<traits_type>,boost::xpressive::detail::true_xpression>,bo ost::mpl::true_>,boost::xpressive::detail::static_xpression<boost::xpres sive::detail::end_matcher,boost::xpressive::detail::no_next>>>, 1> PrimitiveTransform=boost::xpressive::Grammar<char> (boost::xpressive::grammar_detail::as_repeat<char,boost::xpressive::Gram mar<char>,boost::mpl::true_>), 1> Expr=const boost::proto::exprns_::expr<boost::proto::tagns_::tag::unary_plus,boost: :proto::argsns_::list1<const boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::p roto::argsns_::term<boost::xpressive::detail::posix_charset_placeholder> ,0> &>,1> &, 1> State=boost::xpressive::detail::static_xpression<boost::xpressive::detai l::string_matcher<traits_type,boost::mpl::false_>,boost::xpressive::deta il::static_xpression<boost::xpressive::detail::simple_repeat_matcher<boo st::xpressive::detail::static_xpression<boost::xpressive::detail::posix_ charset_matcher<traits_type>,boost::xpressive::detail::true_xpression>,b oost::mpl::true_>,boost::xpressive::detail::static_xpression<boost::xpre ssive::detail::end_matcher,boost::xpressive::detail::no_next>>>, 1> Data=boost::xpressive::detail::xpression_visitor<std::_String_const_iter ator<char,std::char_traits<char>,std::allocator<char>>,boost::mpl::false _,traits_type> , 1> B=true, 1> Tag=boost::proto::tagns_::tag::unary_plus, 1> Args=boost::proto::argsns_::list1<const boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::p roto::argsns_::term<boost::xpressive::detail::posix_charset_placeholder> ,0> &>, 1> Arity=1, 1> Traits=traits_type, 1> ICase=boost::mpl::false_, 1> BidiIter=std::_String_const_iterator<char,std::char_traits<char>,std::al locator<char>> 1> ] 1> c:\Boost\include\boost-1_49\boost/proto/transform/call.hpp(168) : see declaration of 'boost::proto::call<PrimitiveTransform>::impl2<Expr,State,Data,B>::opera tor ()' 1> with 1> [ 1> PrimitiveTransform=boost::xpressive::Grammar<char> (boost::xpressive::grammar_detail::as_repeat<char,boost::xpressive::Gram mar<char>,boost::mpl::true_>), 1> Expr=const boost::proto::exprns_::expr<boost::proto::tagns_::tag::unary_plus,boost: :proto::argsns_::list1<const boost::proto::exprns_::expr<boost::proto::tagns_::tag::terminal,boost::p roto::argsns_::term<boost::xpressive::detail::posix_charset_placeholder> ,0> &>,1> &, 1> State=boost::xpressive::detail::static_xpression<boost::xpressive::detai l::string_matcher<traits_type,boost::mpl::false_>,boost::xpressive::deta il::static_xpression<boost::xpressive::detail::simple_repeat_matcher<boo st::xpressive::detail::static_xpression<boost::xpressive::detail::posix_ charset_matcher<traits_type>,boost::xpressive::detail::true_xpression>,b oost::mpl::true_>,boost::xpressive::detail::static_xpression<boost::xpre ssive::detail::end_matcher,boost::xpressive::detail::no_next>>>, 1> Data=boost::xpressive::detail::xpression_visitor<std::_String_const_iter ator<char,std::char_traits<char>,std::allocator<char>>,boost::mpl::false _,traits_type> , 1> B=true 1> ] ------------------------------------------------------------------------ ---------------------------------------- Thanks in advance for any assistance. Brian Lawry blawry(a)cccglobal.com Compressor Controls Corp Manufacturing Software Engineer /"\ ASCII Ribbon Campaign \ / no HTML in email & vCards X no proprietary attachments / \ use open standards

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[Random] Noob question: Random number generators inside function
by Błażej Jaworowski 25 Apr '12

25 Apr '12

I have a Monte Carlo simulation program (Ising model) in which I wanted to use Boost.Random number generators instead of one from *Numerical Recipes. *It works when the generator is called only in main, but when I use it inside function, I have "identifier not found". I don't want to initialize them each time I call a function because this will repeat the sequences of random number. Is there a way to overcome it? I don't know much about typedefs and templates, so my initialization of the generator is just copied from some tutorial and changed in, I hope, appropriate places. Here is the example code (I wouldn't paste original program, it's too long, but here is the same problem) // random_test.cpp : Defines the entry point for the console application. // #include "stdafx.h" #include "iostream" #include <ctime> #include <boost/random.hpp> using namespace std; namespace boost { namespace random { template<typename UIntType, int w, unsigned int p, unsigned int q> class lagged_fibonacci_engine; template<typename RealType, int w, unsigned int p, unsigned int q> class lagged_fibonacci_01_engine; typedef lagged_fibonacci_01_engine< double, 48, 607, 273 > lagged_fibonacci607; typedef lagged_fibonacci_01_engine< double, 48, 1279, 418 > lagged_fibonacci1279; typedef lagged_fibonacci_01_engine< double, 48, 2281, 1252 > lagged_fibonacci2281; typedef lagged_fibonacci_01_engine< double, 48, 3217, 576 > lagged_fibonacci3217; typedef lagged_fibonacci_01_engine< double, 48, 4423, 2098 > lagged_fibonacci4423; typedef lagged_fibonacci_01_engine< double, 48, 9689, 5502 > lagged_fibonacci9689; typedef lagged_fibonacci_01_engine< double, 48, 19937, 9842 > lagged_fibonacci19937; typedef lagged_fibonacci_01_engine< double, 48, 23209, 13470 > lagged_fibonacci23209; typedef lagged_fibonacci_01_engine< double, 48, 44497, 21034 > lagged_fibonacci44497; } } void generate(); int _tmain(int argc, _TCHAR* argv[]) {const int rangeMin = 1; const int rangeMax = 10; typedef boost::uniform_real<> NumberDistribution; typedef boost::random::lagged_fibonacci9689 RandomNumberGenerator; typedef boost::variate_generator<RandomNumberGenerator&, NumberDistribution> Generator; NumberDistribution distribution(rangeMin, rangeMax); RandomNumberGenerator generator; Generator numberGenerator(generator, distribution); generator.seed(time(0)); // seed with the current time generate(); return 0; } void generate(){cout << numberGenerator() << endl;}

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compiler.hpp problem
by Petros 24 Apr '12

24 Apr '12

Hi, I am using boost 1.48 with msvc2010 on win7. When compiling, I get the following error ( and then many more on the same file ) : C:\_petros\_otc\ext\boost_1_48_0\boost/mpl/aux_/config/compiler.hpp(1): error C2059: syntax error : ':' I tried to look into the file and it does not look like an ordinary C++ header. I have no idea what to do with this error message.. On my laptop (boost 1.47) it does not give me this message. One more thing: I had to reinstall win7 and copied the previously saved boost build which then copied to the proper directory. Any ideas/input will be greatly appreciated. TIA, Petros

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Re: [Boost-users] passing compiler directives
by Matt Priest 24 Apr '12

24 Apr '12

Hello, I'm not sure if this is the standard etiquette for this mailing list, but I thought I would follow up on solution I found for this issue. Maybe it's of value to someone. I had assumed that the required dependencies needed by the source file, unique_path.cpp, weren't getting there because of an inability to get the location to the compiler. It turns out that "read" and "close" aren't available via the <fcntl.h> header on this system (SuSE 11.?). They are available in the <unistd.h>... clearly a minor issue. I was not enthused about modifying the source files in the boost tree, but adding the "#include <unistd.h>" fixed the issue. Recompiling and adding the Bzip libs/header resulted in 1014 targets built with no "fail" messages. Here was the edit to "libs/filesystem/v3/src/unique_path.cpp", line #31: 27-#include <boost/filesystem/v3/operations.hpp> 28- 29-# ifdef BOOST_POSIX_API 30-# include <fcntl.h> 31:# include <unistd.h> 32-# else // BOOST_WINDOWS_API 33-# include <windows.h> Matt Subject: passing compiler directives Date: Mon, 23 Apr 2012 14:24:00 -0500 From: Matt Priest <mpriest(a)cray.com><mailto:mpriest@cray.com> To: <boost-users(a)lists.boost.org><mailto:boost-users@lists.boost.org> Hello, In advance, please excuse this newbie question. I am trying to build boost_1_48_0 and it is going well for all but 4 targets, two of which are the disclaimed <iostreams> failures relating to the bzip targets. However, I'm getting errors when trying to build : boost_1_48_0/libs/filesystem/v3/src/unique_path.cpp Here's the error (there's a nearly duplicate error for the statically linked target): gcc.compile.c++ /users/mpriest/Docs/Boost/build/boost/bin.v2/libs/filesystem/build/gcc-4.7.0/release/threading-multi/v3/src/unique_path.o libs/filesystem/v3/src/unique_path.cpp: In function 'void {anonymous}::system_crypt_random(void*, std::size_t, boost::system::error_code*)': libs/filesystem/v3/src/unique_path.cpp:68:49: error: 'read' was not declared in this scope libs/filesystem/v3/src/unique_path.cpp:71:17: error: 'close' was not declared in this scope libs/filesystem/v3/src/unique_path.cpp:79:13: error: 'close' was not declared in this scope "gcc" -ftemplate-depth-128 -O3 -finline-functions -Wno-inline -Wall -m64 -pthread -fPIC -DBOOST_ALL_NO_LIB=1 -DBOOST_FILESYSTEM_DYN_LINK=1 -DBOOST_SYSTEM_DYN_LINK=1 -DNDEBUG -I"." -c -o "/users/mpriest/Docs/Boost/build/boost/bin.v2/libs/filesystem/build/gcc-4.7.0/release/threading-multi/v3/src/unique_path.o" "libs/filesystem/v3/src/unique_path.cpp" ...failed gcc.compile.c++ /users/mpriest/Docs/Boost/build/boost/bin.v2/libs/filesystem/build/gcc-4.7.0/release/threading-multi/v3/src/unique_path.o... It seems like a simple include file availability issue or a pre-processor define issue, but I can't seem to affect a change in that compiler command through the user-config.jam file edits. When I run b2 with --debug-configuration option, I clearly see that change the -L and -I options in the user-config.jam file is reflected in the output, but still only see the -I"." option as shown above. It seems to me that those functions, read and close, should be made available through including the usual <fcntl.h>, and I think it's a bit curious that no other targets fail from the lack of "read" and "close". Any insight would be appreciated... thank you. Matt

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Re: [Boost-users] [Test] Compiling libraries for Windows Mobile 6 ARMV4I
by Daniel Angel Muñoz Trejo 24 Apr '12

24 Apr '12

Hi Paul, I'm also trying to compile boost for WM6 ARMV4I with STLPort 5.2.1. I'm stuck still in the STLPort part. What steps did you follow to build STLPort 5.2.1 and then boost? I'm stuck in things like this for example: The configure --help of stlport states for evc9: (*) For these compilers the target processor is determined automatically. You must run the WCE*.BAT file you wish to build STLport for before running configure. But there isn't any WCE*.bat file in stlport zip. Do you (or anyone else) remember what steps did you follow to build? Thanks! -- Daniel Angel Muñoz Trejo

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[Preprocessor] ternary identity macro
by Sebastian Pfützner 24 Apr '12

24 Apr '12

Hello, I often write something like #define TEXT(z, n, data) data BOOST_PP_ENUM(5, TEXT, xxx) in my code to create a comma separated list of words. Is there already a macro like TEXT in boost? Or is there a even better way to do what I want? Thanks in advance

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map of ranges?
by Sven Bauhan 24 Apr '12

24 Apr '12

Hi, i was thinking of something like a map of ranges, but i did not get the range concept in boost yet. So what i want is something like: typedef map< range<time_duration>, Color> AgeColorMap; Is it possible to use something like that with the boost library? Thanks, Sven

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Please tell me how to add PKG-CONFIG Support in bjam ?
by Baba Prasad 24 Apr '12

24 Apr '12

Dear friends, Please tell me how to set the pkg-config in bjam. please see like this I am using while compiling the using gcc and make command 1) gcc -g - o `pkg-config --cflags glib-2.0 dbus-glib-1 --libs glib-2.0 dbus-glib-1` main main.c but I don't know how to add this option in bajm and I don't know where to add this option in either jamfile or boost-build.jam. because you might get doubt why do you want use glib and dbus means I using dbus api's in my program. If it should be add in boost-build.jam file means it is already have the following boost-build /home/kaka/Documents/seamo/boost_1_49_0/tools/build/v2 ; so how to and where to add is my big confusion , please if any one knows could help me get out of this problem. Best Regards BaBu -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean.

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passing compiler directives
by Matt Priest 23 Apr '12

23 Apr '12

Hello, In advance, please excuse this newbie question. I am trying to build boost_1_48_0 and it is going well for all but 4 targets, two of which are the disclaimed <iostreams> failures relating to the bzip targets. However, I'm getting errors when trying to build : boost_1_48_0/libs/filesystem/v3/src/unique_path.cpp Here's the error (there's a nearly duplicate error for the statically linked target): gcc.compile.c++ /users/mpriest/Docs/Boost/build/boost/bin.v2/libs/filesystem/build/gcc-4.7.0/release/threading-multi/v3/src/unique_path.o libs/filesystem/v3/src/unique_path.cpp: In function 'void {anonymous}::system_crypt_random(void*, std::size_t, boost::system::error_code*)': libs/filesystem/v3/src/unique_path.cpp:68:49: error: 'read' was not declared in this scope libs/filesystem/v3/src/unique_path.cpp:71:17: error: 'close' was not declared in this scope libs/filesystem/v3/src/unique_path.cpp:79:13: error: 'close' was not declared in this scope "gcc" -ftemplate-depth-128 -O3 -finline-functions -Wno-inline -Wall -m64 -pthread -fPIC -DBOOST_ALL_NO_LIB=1 -DBOOST_FILESYSTEM_DYN_LINK=1 -DBOOST_SYSTEM_DYN_LINK=1 -DNDEBUG -I"." -c -o "/users/mpriest/Docs/Boost/build/boost/bin.v2/libs/filesystem/build/gcc-4.7.0/release/threading-multi/v3/src/unique_path.o" "libs/filesystem/v3/src/unique_path.cpp" ...failed gcc.compile.c++ /users/mpriest/Docs/Boost/build/boost/bin.v2/libs/filesystem/build/gcc-4.7.0/release/threading-multi/v3/src/unique_path.o... It seems like a simple include file availability issue or a pre-processor define issue, but I can't seem to affect a change in that compiler command through the user-config.jam file edits. When I run b2 with --debug-configuration option, I clearly see that change the -L and -I options in the user-config.jam file is reflected in the output, but still only see the -I"." option as shown above. It seems to me that those functions, read and close, should be made available through including the usual <fcntl.h>, and I think it's a bit curious that no other targets fail from the lack of "read" and "close". Any insight would be appreciated... thank you. Matt

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[serialization] Serializing a byte*
by Sean Farrow 23 Apr '12

23 Apr '12

Hi: I have a function in another library that outputs a byte*. Can I safely just serialize this with boost.serialization, or should I be doing something else to make this work. Any help appreciated. Cheers Sean.

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PKG-CONFIG Support in bjam is how
by Baba Prasad 23 Apr '12

23 Apr '12

Dear friends, Please tell me how to set the pkg-config in bjam. please see like this I am using while compiling the using gcc and make command 1) gcc -g - o `pkg-config --cflags glib-2.0 dbus-glib-1 --libs glib-2.0 dbus-glib-1` main main.c but I don't know how to add this option in bajm and I don't know where to add this option in either jamfile or boost-build.jam. because you might get doubt why do you want use glib and dbus means I using dbus api's in my program. If it should be add in boost-build.jam file means it is already have the following boost-build /home/kaka/Documents/seamo/boost_1_49_0/tools/build/v2 ; so how to and where to add is my big confusion , please if any one knows could help me get out of this problem. Best Regards BaBu -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean.

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Subject: [Property Tree] Insert child node at the top of ptree
by johnnyturbo3 23 Apr '12

23 Apr '12

Hello all, I'm trying to find a way to write a child node to the top of a ptree, instead of the bottom as default. I've tried a number of things but for something that should be so simple I've had no luck. The reason I want to write a node to the top of the structure is because when I use ptree::get_child(), it fetches the first node match in the tree i.e. the oldest node written, not the latest written. I've posted the question on stackoverflow.com, it may explain some more detail: http://stackoverflow.com/questions/10272371/add-child-node-to-top-of-xml-st… I hope I've explained my problem clearly. Thanks in advance! Nathan

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Boost.Atomic documentation, Reference Counting
by Václav Zeman 23 Apr '12

23 Apr '12

Hello. Your documentation to Boost.Atomic ([1]) has been given me as an answer to my StackOverflow ([2]) question. Here is a snippet from the documentation: friend void intrusive_ptr_release(const X * x) { if (x->refcount_.fetch_sub(1, boost::memory_order_release) == 1) { boost::atomic_thread_fence(boost::memory_order_acquire); delete x; } } And your rationale: "It is important to enforce any possible access to the object in one thread (through an existing reference) to happen before deleting the object in a different thread. This is achieved by a "release" operation after dropping a reference (any access to the object through this reference must obviously happened before), and an "acquire" operation before deleting the object." I wonder why this would not work well if it looked like this instead: friend void intrusive_ptr_release(const X * x) { if (x->refcount_.fetch_sub(1, boost::memory_order_relaxed) == 1) { boost::atomic_thread_fence(boost::memory_order_acq_rel); delete x; } } [1] <http://www.chaoticmind.net/~hcb/projects/boost.atomic/doc/atomic/usage_exam…> [2] <http://stackoverflow.com/questions/10268737/c11-atomics-and-intrusive-share…> -- VZ

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[multi_index] A multi_index where one index is a subset of the whole collection
by Philipp Moeller 22 Apr '12

22 Apr '12

Hi, I've asked this question [1] two days ago on stackoverflow.com but haven't gotten any answer on it, yet. So I'll try it here. [1] http://stackoverflow.com/questions/10217601/a-multi-index-where-one-index-i… If this is not possible out of the box, can I write my own indices for multi_index that would allow such functionality? Cheers, Philipp Moeller GeometryFactory

2 1

[thread] safe portable static mutex initialization
by Serge Skorokhodov 22 Apr '12

22 Apr '12

Hello, I've read Anthony Williams' articles and documentation but still have no definite answer. Thus two questions: 1. Is it safe to use a block level static boost::mutex on Unix and Windows? 2. Is it safe to use a file/class level static boost::mutex on Unix and Windows? TIA -- The fish that is singing in Ucayali river...

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Re: [Boost-users] boost::filesystem::path operator/= is broken for char[1] in 1.48 (Nat Linden)
by ZNV 21 Apr '12

21 Apr '12

Hi Nat, >> I believe the current operator =/ behavior is outright dangerous and > >> should be fixed. > > Nope, sorry. If you pass a fixed-length array, a proper C++ library > *should* be sensitive to its max. Anything else is unsafe and should > be discouraged. > What if I pass fixed-length array without actually knowing that? There are many C libraries out there assuming char * and char [] are interchangeable. These libraries are well documented. You won't check the source code beforehand if you have the docs, will you? The fact that we're still dealing with legacy C-style APIs is not a > good reason for a modern C++ library to blithely run past the declared > end of a char array. C++ tries very hard to bring type-safety to the > party. It is far more important to try to keep new code from crashing > than it is to accommodate such misleading APIs. > I totally agree with you – type safety is an important C++ feature. It is supposed to help a programmer by eliminating more errors early. But you've achieved just the opposite result with your creative abuse of C++ type system. I would've agreed with your resolution if appending char[1] to boost::filesystem::path resulted in a static_assert. This would allow to apply the proposed workaround immediately (cast to char *). Unfortunately boost::filesystem have chosen to break my code silently instead. I had to hunt the bug in debugger – the same very thing the type safety was supposed to prevent, is not it? So yes technically my program did not crash. But I totally believe that it is not only preventing new code from crashing which is important. Eliminating obscure pitfalls the new code is suffering from is equally important. Every engineering problem is a quest for a better tradeoff. Concerning appending fixed-length array of length one or less to a boost::filesystem::path we are facing the following choices 1) silently treat the operation as a no-op (current) 2) treat it the same way as char * 3) static_assert In my opinion (1) is the worst possible choice since it breaks the code silently in a non-obvious way. When you know you're dealing with code that willfully lies to the > compiler -- even if it's been frozen into an OS API -- use Ovanes's > workaround to pass char* rather than char[size]. > See above.

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Re: [Boost-users] boost::filesystem::path operator/= is broken for char[1] in 1.48 (Ovanes Markarian)
by ZNV 21 Apr '12

21 Apr '12

Hello Ovanes, > This over-allocation is pretty much the same as reserving some space at the > end of the data structure to place data together. Am I right? Why isn't it > possible to just write char[128] or char[16] instead of char[1]? I can't change that code because it lives in a system header. > And if > you know that this buffer represents some special case, why don't you pass > it as such to filesystem? &char[0], than boost::filesystem will not assume > it got char[1] and will be looking to '\0' marker... > How would I know that this buffer represents some special case? FTS(3) library documentation says something like that: struct _ftsent { ... char *fts_name; }; But the structure is really defined another way (Linux, Mac OS X): struct _ftsent { ... char fts_name[1]; }; I believe this discrepancy is pretty much negligible anyway. There are huge number of programs utilizing fts(3) APIs and they don't break. Unfortunately boost::filesystem is another story. It does break and it does break silently.

1 0

boost::filesystem::path operator/= is broken for char[1] in 1.48
by Nick Zavaritsky 21 Apr '12

21 Apr '12

Hi! Please consider the code below: === BUG === boost::filesystem::path some_path("first"); char path_component[1]; /* = "second" */ some_path /= path_component; Some_path value is expected to be "first/second" but it is "first". I.e operator /= had no effect. === END BUG === Concerning a longer string in a char[1] buffer. Actually path_component is the *last* field in a heap-allocated structure. The structure is over-allocated to enable storing a longer string in a char[1] buffer. This technique is often used in C code. Here is operator /= callstack. #0 boost::filesystem3::path_traits::empty<char const, 1ul> () at path_traits.hpp:89 #1 0x0000000100001e7e in boost::filesystem3::path::append<char [1]> (this=0x7fff5fbff910, source=@0x100100270, cvt=@0x100100280) at path.hpp:655 #2 0x0000000100001f77 in boost::filesystem3::path::operator/=<char [1]> (this=0x7fff5fbff910, source=@0x100100270) at path.hpp:235 The relevant excerpt from boost::filesystem3::path_traits::empty follows: namespace path_traits { ... template <typename T, size_t N> inline bool empty(T (&)[N]) { return N <= 1; } ... } It appears that boost::filesystem::path treats char[1] as an empty path regardless of the actual content. This is definitely wrong due to so many C libraries storing long strings in char[1] buffers. In particular on Mac OS X fts(3) FTSENT::fts_name is char[1]. I believe the current operator =/ behavior is outright dangerous and should be fixed. By the way the only code currently benifiting from the boost::filesystem::path being overly smart is the code appending "" (empty string literal) to pathes.

4 3

MSM: Separating templatized on_entry/on_exit into cpp/h
by ev_mp 20 Apr '12

20 Apr '12

Hello, I'm trying to modify the Player example and to separate the on_exit/on_entry template function definition from declaration so I can hide the actual implementation details. "My.h" ... namespace myNamespace { ... // Concrete FSM implementation struct player_state_machine : public msm::front::state_machine_def { ... struct Playing : msm::front::state<> { template void on_entry(event const &, player_state_machine & ); // { "My Secret Code } } ...... } } "My.cpp" namespace myNamespace { ... template void myNamespace::player_state_machine::Playing::on_entry(Event const &, player_state_machine & ); { Here I want to put the actual implementation... } Is this feasible ? If not - what are the alternatives ? As I previously said - putting the implementation into the header is not an option. Any help will be appreciated. Evgeni -- View this message in context: http://boost.2283326.n4.nabble.com/MSM-Separating-templatized-on-entry-on-e… Sent from the Boost - Users mailing list archive at Nabble.com.

2 3

boost mpi and mvapich
by Cornelius Steinhardt 20 Apr '12

20 Apr '12

Hi, have somebody compiled the boost_1.48 with a mvapich compiler? The test from boost mpi get started, which tests the mpi installation works fine. Than i installed the whole library, with adding using mpi : path_to/mpiCC ; into the user-config.jam After this i run ./bootstrap --prefix=where_to_install and ./bjam --prefix=where_to_install install My next step was to test the installation with the first program code from the boost mpi tutorial. ("I am process " << world.rank() << " of " << world.size()) But i get a deadlock in the line mpi::environment env(argc, argv); Can somebody explain me why? or where my failure is? Regards Cornelius

1 0

How to send list from Python to boost python
by Guruswamy B M 20 Apr '12

20 Apr '12

Hi, I have been using boost python for one of my application. In the same I have to send list from python to boost wrapper. Ex:. >From python. a = [1, 2, 3, 4] test(a); In wrapper my C++ fucntion should be like below: void test(list a) { list processing. } I tried similar way, but getting an signature error. I need a help on how to send list from the python, so that can access each element of list in C++ wrapper. Thanks and Regards, Guru

2 2

How to send python list to c++ function
by Guruswamy B M 20 Apr '12

20 Apr '12

Hi, I have been using boost python for one of my application. In the same I have to send list from python to boost wrapper. Ex:. >From python. a = [1, 2, 3, 4] test(a); In wrapper my C++ fucntion should be like below: void test(list a) { list processing. } I tried similar way, but getting an signature error. I need a help on how to send list from the python, so that can access each element of list in C++ wrapper. Thanks and Regards, Guru

2 2

Re: [Boost-users] Timeout on read/write using Boost.Asio
by boost 20 Apr '12

20 Apr '12

So, it implies that it is a bad idea to implement timeout read/write using timer and "cancel". Is there any better solution? Best Regards Zhanwei Wang ----- Original Message -----From: Igor R <boost.lists(a)gmail.com> To: boost-users(a)lists.boost.org > What if I cancel all the async operation, is there any partial data which has been read from or write to socket after the cancelation? > If partial data has been read from or write to socket, how can I issue both async read/write again? Right, some data might have been sent/received, and you have to re-synchronise somehow your client and server. Even if it's possible, it would be pretty complicated. Besides, cancellation is not quite portable: http://www.boost.org/doc/libs/1_49_0/doc/html/boost_asio/reference/basic_st… That's why it's usually a bad idea to cancel operations on a socket. Instead, you can just close the socket and then re-establish connection from scratch. > I cancel the read/write on a tcp connection because the current node I connected to may be too busy to response, so I can try another node. I do not want cancel all async request because the other pending operations may finish successfully, the workload on peer node is very heavy instead of failure. Well, I don't know what you application does, but I'm afraid it's not the right way to go. First of all, why can't you connect all the "nodes" you need? Anyway, you should decide for every particular connection whether it's ok or "faulty" (returned error, takes too much time, no ping, no heartbeat, etc...): if it's ok - wait for response, if it's faulty - just close it. _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users

1 0

Re: [Boost-users] Timeout on read/write using Boost.Asio
by boost 19 Apr '12

19 Apr '12

hi, Thanks for your reply. I cancel the read/write on a tcp connection because the current node I connected to may be too busy to response, so I can try another node. I do not want cancel all async request because the other pending operations may finish successfully, the workload on peer node is very heavy instead of failure. Anyway, I can cancel all request, but I still have the question about the cancel. What if I cancel all the async operation, is there any partial data which has been read from or write to socket after the cancelation? If partial data has been read from or write to socket, how can I issue both async read/write again? Best Regards Zhanwei Wang ----- Original Message -----From: Igor R <boost.lists(a)gmail.com> To: boost-users(a)lists.boost.org > My question is: > the "cancel" call acutely cancel all the pending async operation, but only one of them is timeout. > For example, there is a pending async read and a pending async write operation, only read is timeout, I do not want cancel write any way. Yes, you're right. You'll have to issue both async read and write again. But usually "timeout" means that something goes wrong with the connection (i.e. you expected something, but it failed to happen). _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users

2 1

Questions about using "mcregor_common_subgraphs" algorithm in Boost Graph Library
by Bin Ren 19 Apr '12

19 Apr '12

Hi, I am a beginner of C++ Boost Library. I am doing a project about "Maximum Common Subgraph" Algorithm, and I found there is an implementation in Boost Graph Library: "boost/graph/mcgregor_common_subgraphs.hpp" I use it like this: (and my question is marked as red) ---------------------------------------------------------------------------------------------------- //Compare the input graphs against the Graph Forest for (int i = 0; i < graphInputs.size(); ++i){ graph_t * pInputGraphi = graphInputs[i]; for (int j = 0; j < graphForest.size(); ++j) { std::cout << "Common Sub graph of input graph" << i << " and graph" << j << " :" << std::endl; //Compare one to one among graphi and graphj graph_t * pGraphj = graphForest[j]; //Here I am using the callback function from the example code: "mcgregor_subgraphs_example.cpp" example_callback<graph_t> my_callback(*pInputGraphi); property_map<graph_t, vertex_name_t>::type vname_mapi = get(vertex_name, *pInputGraphi); property_map<graph_t, vertex_name_t>::type vname_mapj = get(vertex_name, *pGraphj); property_map<graph_t, edge_name_t>::type ename_mapi = get(edge_name, *pInputGraphi); property_map<graph_t, edge_name_t>::type ename_mapj = get(edge_name, *pGraphj); //Print out Maximum connected Common Subgraphs between graphi and graphj mcgregor_common_subgraphs_maximum_unique(*pInputGraphi, *pGraphj, true, my_callback, //edges_equivalent(make_property_map_equivalent(ename_mapi, ename_mapj)), //Here is my problem: if I use both edges_equivalent and vertices_equivalent, the code can not be compiled //However, if I only use vertices_equivalent, I doubt whether the maximum common subgraph result is correct. //If I use edges_equivalent only, the code can be compiled, however, it runs into an infinite loop. vertices_equivalent(make_property_map_equivalent(vname_mapi, vname_mapj))); } } ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ Is there any way to use both the edges_equivalent and the vertices_equivalent (Or it is not necessary at all)? BTW, it seems the performance of this algorithm is not perfect; for a small test case below, it needs around 5 seconds by vertices_equivalent, while it loops for a very long time for edges_equivalent (it might be a infinite loop...). Looking forward to your feedback. Thanks and have a good night, Bin ----------------------------------------------------------------------------------------------- Small Test Case: For test, I only use one graph for "graphInputs", and one graph for "graphForest": graphInputs: (v: vertex, 1st number: the vertex id, 2nd number: the vertex name; e: edge, 1st: source vertex, 2nd: target vertex, 3rd: edge name) t # 0 v 0 0 v 1 0 v 2 0 v 3 0 v 4 0 v 5 0 v 6 1 v 7 1 v 8 1 v 9 1 v 10 2 v 11 0 v 12 0 v 13 2 v 14 0 v 15 0 v 16 0 v 17 0 v 18 1 v 19 1 v 20 1 v 21 3 v 22 3 v 23 4 v 24 5 v 25 5 e 0 1 3 e 1 2 3 e 2 3 3 e 3 4 3 e 4 5 3 e 5 0 3 e 0 6 0 e 1 7 0 e 4 8 0 e 5 9 0 e 2 10 0 e 10 11 0 e 11 12 3 e 12 13 0 e 13 3 0 e 11 14 3 e 14 15 3 e 15 16 3 e 16 17 3 e 17 12 3 e 14 18 0 e 15 19 0 e 17 20 0 e 13 21 1 e 10 22 1 e 16 23 0 e 23 24 0 e 23 25 0 graphForest: t # 1 v 0 0 v 1 0 v 2 0 v 3 0 v 4 0 v 5 0 v 6 1 v 7 1 v 8 1 v 9 1 v 10 1 v 11 4 v 12 4 v 13 6 v 14 5 v 15 3 e 0 1 3 e 1 2 3 e 2 3 3 e 3 4 3 e 4 5 3 e 5 0 3 e 0 6 0 e 1 7 0 e 2 8 0 e 3 9 0 e 5 10 0 e 4 11 0 e 11 12 0 e 11 13 0 e 13 14 0 e 12 15 1 If we only use vertex_equivalent, we can get some result like this: This is input Graph 0 <--> 1 5 6 1 <--> 0 2 7 2 <--> 1 3 10 3 <--> 2 4 13 4 <--> 3 5 8 5 <--> 4 0 9 6 <--> 0 7 <--> 1 8 <--> 4 9 <--> 5 10 <--> 2 11 22 11 <--> 10 12 14 12 <--> 11 13 17 13 <--> 12 3 21 14 <--> 11 15 18 15 <--> 14 16 19 16 <--> 15 17 23 17 <--> 16 12 20 18 <--> 14 19 <--> 15 20 <--> 17 21 <--> 13 22 <--> 10 23 <--> 16 24 25 24 <--> 23 25 <--> 23 This is the Graph in Forest: 0 <--> 1 5 6 1 <--> 0 2 7 2 <--> 1 3 8 3 <--> 2 4 9 4 <--> 3 5 11 5 <--> 4 0 10 6 <--> 0 7 <--> 1 8 <--> 2 9 <--> 3 10 <--> 5 11 <--> 4 12 13 12 <--> 11 15 13 <--> 11 14 14 <--> 13 15 <--> 12 Start to do Maximum Common Subgraph Search: Found common subgraph (size 10) 0 <--> 1 5 6 1 <--> 0 2 7 2 <--> 1 3 3 <--> 2 4 4 <--> 3 5 8 5 <--> 4 0 9 6 <--> 0 7 <--> 1 8 <--> 4 9 <--> 5 ....

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[Interprocess] Opposite of find_or_construct()
by Aaron_Wright＠selinc.com 19 Apr '12

19 Apr '12

I feel like I'm missing something simple. I have multiple processes that are going to use an object in shared memory. The find_or_construct() method lets these processes get a pointer to the object without worrying about startup order. What about the opposite? When a process is done with the object in shared memory it can't destroy it because the other processes may be using it. Is there a destroy_or_not() method that would only destroy the object when everyone is done with it? Normally I would solve this with a smart pointer like shared_ptr, but I think I'm miss understanding smart_ptr and I can't get it to work right. It seems like the shared_ptr is created in shared memory and needs to be explicitly destroyed, which would bring me back to the original problem, of who actually gets to destroy it. Should I be looking at intrusive_ptr? --- Aaron Wright

1 0

Calling dijkstra on a filtered graph with bundled properties?
by Berit Dangaard Brouer 18 Apr '12

18 Apr '12

Hi there, First of all thank you for the boost graph library - I really enjoy working with it. However I have become challenged in calling Dijkstra on a filtered graph with bundled properties: My graph structure "mcf_graph" looks like this: #ifndef MCF_GRAPH_HPP #define MCF_GRAPH_HPP #include <boost/config.hpp> #include <boost/graph/adjacency_list.hpp> #include <iostream> using namespace boost; using namespace std; struct Port { Port(int index=-1, int type=0, int port_code=0, string UN="NN", string name="NN", int service_id=-1 ): m_index(index), m_type(type), m_port_code( port_code), UNLOCODE(UN), m_name(name), m_service_id(service_id) {} int m_index; int m_type;//0 port, 1 port call int m_port_code; string UNLOCODE; string m_name; int m_service_id; }; struct Edge { Edge( int id=0, int type=0, double weight=0.0, double dual_cost=0.0, double util=0.0, double cap=0.0, double r_cap=0.0 ) : m_idx(id), m_type(type), m_weight(weight) , m_dual_cost(dual_cost), m_utilization(util), m_capacity(cap), m_res_cap(r_cap) {} unsigned int m_idx; int m_type; double m_weight; double m_dual_cost; double m_utilization; double m_capacity; double m_res_cap; //residual capacity }; template <typename res_cap_map> struct positive_res_cap { positive_res_cap() { } positive_res_cap( res_cap_map cap) : res_cap(cap) { } bool operator()(const Edge& e) const { return 0 < e.m_res_cap; } res_cap_map res_cap; }; //Graph typedef adjacency_list< vecS , vecS , bidirectionalS, Port, Edge> mcf_graph; private: mcf_graph& g; }; #endif I am filtering an mcf_graph like this: //filter positive residual capacity graph positive_res_cap<res_cap_map> filter(get(&Edge::m_res_cap, m_mcf->graph())); filtered_graph<mcf_graph, positive_res_cap<res_cap_map> > fg(m_mcf->graph(), filter); and then calling Dijkstra like this: vertex_descriptor o_vd; std::vector<vertex_descriptor> p ( num_vertices ( fg ) ); std::vector<double> d ( num_vertices ( fg ) ); dijkstra_shortest_paths ( fg, o_vd, predecessor_map ( &p[0] ).distance_map ( &d[0] ).weight_map ( get ( &Edge::m_weight,fg ) ).vertex_index_map ( get ( vertex_index,fg ) ) ); and I get the following compilation error: /usr/include/boost/graph/filtered_graph.hpp:75:63: error: no match for call to '(const positive_res_cap<boost::bundle_property_map<boost::adjacency_list<boost::vecS, boost::vecS, boost::bidirectionalS, Port, Edge>, boost::detail::edge_desc_impl<boost::bidirectional_tag, unsigned int>, Edge, double> >) (const boost::detail::edge_desc_impl<boost::bidirectional_tag, unsigned int>&)' /home/berit/svn/MCF/src/IPH/include/mcf_graph.h:54:8: note: candidate is: /home/berit/svn/MCF/src/IPH/include/mcf_graph.h:57:7: note: bool positive_res_cap<res_cap_map>::operator()(const Edge&) const [with res_cap_map = boost::bundle_property_map<boost::adjacency_list<boost::vecS, boost::vecS, boost::bidirectionalS, Port, Edge>, boost::detail::edge_desc_impl<boost::bidirectional_tag, unsigned int>, Edge, double>] /home/berit/svn/MCF/src/IPH/include/mcf_graph.h:57:7: note: no known conversion for argument 1 from 'const boost::detail::edge_desc_impl<boost::bidirectional_tag, unsigned int>' to 'const Edge&' The above call to Dijkstra works on a non-filtered graph. Can anyone help me out in both understanding why it does not work for the predicate (Is it because the iterators are different???) and how to solve my problem? Thanks in advance ! Berit -- Best Regards, Berit Dangaard Brouer (formerly Løfstedt) PhD. Student DTU Management Engineering, Operations Research Technical University of Denmark Department of Management Engineering Produktionstorvet, Bygning 426 2800 Kgs. Lyngby blof(a)dtu.dk <mailto:blof@man.dtu.dk> www.or.man.dtu.dk <http://www.or.man.dtu.dk>

2 1

Timeout on read/write using Boost.Asio
by boost 18 Apr '12

18 Apr '12

Hi everyone I'm using boost asio to implement a tcp client in my project, and it is my first time of using asio. I need timeout when read/write on the socket and I found the solution of using async io plus a timer, if timeout, cancel the async io operation. My question is: the "cancel" call acutely cancel all the pending async operation, but only one of them is timeout. For example, there is a pending async read and a pending async write operation, only read is timeout, I do not want cancel write any way. Any suggestion of the solution? Or I' m wrong? Thanks

2 1

shared_ptr and container iterators
by Johannes Totz 18 Apr '12

18 Apr '12

Hi all, just started playing with boost::shared_ptr. How do I get a const iterator pointing to a shared_ptr pointing to a const object? See code below, I'd like to prevent a MyItem being changed through const iterators. struct MyItem { int value; }; struct MyContainer { typedef std::set<boost::shared_ptr<MyItem> > MySet; MySet set; }; int main(int argc, char* argv[]) { MyContainer mc; boost::shared_ptr<MyItem> p(new MyItem); p->value = 5; mc.set.insert(p); MyContainer::MySet::const_iterator i = mc.set.begin(); // cannot mutate shared_ptr pointed to by iterator: ok //(*i).reset(new MyItem); // cannot change ptr but can change value: ok (*i)->value = 6; MyContainer::MySet::iterator j = mc.set.begin(); (*j).reset(new MyItem); // how to do this? // should not change ptr nor MyItem std::set<boost::shared_ptr<const MyItem> >::const_iterator k = mc.set.begin(); return 0; }

4 7

Implementing python's enumerate with iterator adaptors
by Jens Auer 18 Apr '12

18 Apr '12

Hi, I am implementing something similar to python's enumerate using boost iterator adapter, but I am running into two problems I am unable to solve. Both problems use my Enumerate-adaptor defined as: #include <utility> #include <boost/iterator/iterator_adaptor.hpp> namespace Iterator { // some simple wrapper to have better names than std::pair template<typename T, typename X> struct Enumerated { Enumerated(T i, X x): count(i), value(x) { } T count; X value; }; template< typename Iterator, typename T = typename Iterator::difference_type> class Enumerator: public boost::iterator_adaptor<Enumerator<Iterator, T>, Iterator, Enumerated<T, typename Iterator::value_type>, boost::use_default, Enumerated<T, typename Iterator::reference> > { public: Enumerator(): mCount(), mPos(), mStep() { } template<typename It> explicit Enumerator(It i, T start=T(), T step=T(1) ): mCount(start), mPos(i), mStep(step) { } private: friend class boost::iterator_core_access; Enumerated<T, typename Iterator::reference > dereference() const { return Enumerated<T, typename Iterator::reference >(mCount, *mPos); } Enumerated<T, typename Iterator::reference > dereference() { return Enumerated<T, typename Iterator::reference >(mCount, mPos); } bool equal(Enumerator<Iterator, T> const& other) const { return mPos == mPos; } void increment() { mCount += mStep; mPos += 1; } void decrement() { mCount -= mStep; mPos -= 1; } void advance(typename Iterator::difference_type step) { mCount += step * mStep; mPos += step; } typename Iterator::difference_type distance_to(Enumerator<Iterator, T> const& other) const { return std::distance(mPos, other.mPos); } T mCount; Iterator mPos; typename Iterator::difference_type mStep; }; template<typename Iterator, typename T> Enumerator<Iterator, T> enumerate(Iterator i, T start=0, T step=1) { return Enumerator<Iterator, T>(i, start, step); } When I compile the following sample program, msvc (VS2010) prints an error, but g++ does not have any problems. #include <vector> #include <iostream> #include <algorithm> void foo() { std::vector<int> v; auto i = Iterator::enumerate(v.begin(), 0, 1); auto j = Iterator::enumerate(v.end(), 0, 1); std::for_each( i, j, [](decltype(*i) e) { std::cout << e.count << ", " << e.value << std::endl; }); } Error 1 error C2665: 'std::_Debug_range2' : none of the 2 overloads could convert all the argument types d:\programme\microsoft visual studio 10.0\vc\include\xutility 728 My second problem can be reproduced with the following sample program on both msvc and g++: #include <vector> #include <iostream> #include <algorithm> void foo() { std::vector<int> v; auto i = Iterator::enumerate(v.begin(), 0, 1); auto y = i->count; auto z = i->value; } MSVC: Error 3 error C2664: 'boost::implicit_cast' : cannot convert parameter 1 from 'Iterator::Enumerated<T,X> *' to 'boost::detail::operator_arrow_proxy<T>' c:\software development\externals\include\boost\iterator\iterator_facade.hpp 326 G++: In file included from /usr/include/boost/iterator/iterator_adaptor.hpp:15:0, from Enumerate.h:18, from Enumerate.cpp:1: /usr/include/boost/iterator/iterator_facade.hpp: In static member function 'static boost::detail::operator_arrow_result<ValueType, Reference, Pointer>::type boost::detail::operator_arrow_result<ValueType, Reference, Pointer>::make(Reference) [with ValueType = Iterator::Enumerated<int, int>, Reference = Iterator::Enumerated<int, int&>, Pointer = Iterator::Enumerated<int, int>*, boost::detail::operator_arrow_result<ValueType, Reference, Pointer>::type = boost::detail::operator_arrow_proxy<Iterator::Enumerated<int, int> >]': /usr/include/boost/iterator/iterator_facade.hpp:648:49: instantiated from 'boost::iterator_facade<I, V, TC, R, D>::pointer boost::iterator_facade<I, V, TC, R, D>::operator->() const [with Derived = Iterator::Enumerator<__gnu_cxx::__normal_iterator<int*, std::vector<int> >, int>, Value = Iterator::Enumerated<int, int>, CategoryOrTraversal = boost::random_access_traversal_tag, Reference = Iterator::Enumerated<int, int&>, Difference = int, boost::iterator_facade<I, V, TC, R, D>::pointer = boost::detail::operator_arrow_proxy<Iterator::Enumerated<int, int> >]' Enumerate.cpp:27:14: instantiated from here /usr/include/boost/iterator/iterator_facade.hpp:327:49: error: no matching function for call to 'implicit_cast(Iterator::Enumerated<int, int&>*)' Any help would be greatly appreciated, Bets regards, Jens

3 7

Stack objects and polymorphic access
by asif saeed 18 Apr '12

18 Apr '12

Hi, I want to maintain stack semantics in my application and avoid heap. For very few requirements, I have to write polymorphic code but I still want to create objects on stack and want to assign their addresses to some abstract base class for polymorphic access. So, all stack variables will be destroyed at the end of their scope and, yet, I'll get polymorphic access. However, functions creating/returning concrete objects have concrete class types. Can boost help me here? Best regards, Asif

1 0

thread safety of shared_ptr
by Yuanlong Shao 18 Apr '12

18 Apr '12

Hi all, If I do the following ---------------------------------------------------------------------------------------------------------- shared_ptr<int> pA( new int(1) ); shared_ptr<int> pB( new int(2) ); shared_ptr<int> pNew( new int(3) ); // thread A pA = pB; // thread B pB = pNew; ---------------------------------------------------------------------------------------------------------- I know that whether pA will be int(2) or int(3) after execution is undefined, but if I do want to do this no matter what value of pA I get, will this cause atomicity problem? I mean, thread A increases counter for int(2), but thread B decrease it, is this thread safe? Yuanlong Shao

2 1

Troubles using boost::circular_buffer
by Ted Byers 17 Apr '12

17 Apr '12

I declare I use it: #include <boost/circular_buffer.hpp> I make my function: double calculateStdDev(const boost::circular_buffer<double>& input, double& mean, double& variance, double& stddev) { if (input.empty()) return 0.0; boost::circular_buffer<double>::const_iterator it = input.begin(), end = input.end(); double M = *it; double Q = 0.0; unsigned int count = 1; ++it; while (it != end) { unsigned int k = count; ++count; double del = *it - M; unsigned int j = k + 1; Q += k * (del * del) / j; M += del / j; ++it; } variance = Q / (count - 1); stddev = std::sqrt(variance); mean = M; return stddev; } This function doesn't need to know are care about the number of items in the buffer. It just makes one pass through the data, from it = inut.begin() to input.end(). This particular algorithm, BTW, provides a solution that is MUCH faster and much more accurate in some cases, than the two pass algorithm, and is much more accurate than the other single pass algorithms you may see recommended. But that isn't the point. In the header that provides the prototypes for the functions in this particular CPP file, I have: double calculateStdDev(const boost::circular_buffer<double>& input, double& mean, double& variance, double& stddev); And gcc v 4.3.4 gives me the following error: ../../include/distribution.moments.hpp:9: error: wrong number of template arguments (1, should be 2) /usr/local/include/boost/circular_buffer/base.hpp:70: error: provided for 'template<class T, class Alloc> class boost::circular_buffer' I am not sure I understand why. Does this mean that I have to make calculateStdDev a template function? E.g.: template <typename T> double calculateStdDev(const boost::circular_buffer<double, T>& input, double& mean, double& variance, double& stddev) { // and put the entire implementation here in the header instead of in the cpp file with the overloads for other types such as std::vector) } But, if that is the case, why is it possible to instantiate such a buffer using the following (as in the example)? boost::circular_buffer<int> cb(3); I must have missed something, but I don't know what. Cheers Ted

2 2

[MSM] a timer/timeout for the whole state machine (including submachines)
by Albert Gil Moreno 17 Apr '12

17 Apr '12

Hi, I've been working for a while with the MSM and I'm very impressed about it... congratulations for your work!! I've to say that I'm not an expert on UML nor state machines and I think that my needs are a very common user-case... so I'm probably missing something! Basically what I need is a (reusable) Timer that, after a number of Clocks, it sends a TimeOut to the state machine, and when the Timer receives a Reset it restarts the counting of clocks. (I want to also add a Pause or similar but this doesn't matter right now...) So, the goal is that any (or all) of my states could be controlled by the Timer and if no events are received for a while a TimeOut will be (always) received/processed. AFAIK there is no concept of timer/timeout in the MSM, but I found very straightforward to implement my idea with an Orthogonal Region with a single state Timer that receives Clock and Reset events and sends a TimeOut. And it worked like a charm!! But I found a problem with one of my states become a submachine... The Timer::Reset action executes a fsm.process_event(Timer::Reset()), but this event is not processed. I realized that "fsm" is the submachine and AFAIK there is no way to access to the parent(est) fsm... So, is there a better or more standard way to implement a Timer/Timeout in UML/MSM? And, although "fsm" is the submachine, why the no_transition function is not executed (this last seems a bug to me...). Albert PD: Do you think that has meaning that the MSM could have an "on_timeout" function for the states (like on_entry/exit?), or to have a timeout event like "none"... ok may be this sounds huge to implement and not so generic...

4 12

Questions about packaged_task , Promise and serialization of a class object and event handling
by Master 16 Apr '12

16 Apr '12

Hello all again . i have couple of questions again which i would appreciate any kind of help and answer, my first question is about packaged_task and how we can use it , i mean i tried using packaged_task with functions , with parameters , and i got errors doing it . so do we always have to use class or stcucts in order for us to use packaged_task ? how can i send some arguments to a function when im trying to make a package out of ? i have done the packaging with parameterelss functions , but i dont know how im supposed to pass parameters ! : here is my application working with parameterless functions . > //in the name of GOD > //Seyyed Hossein Hasan Pour > //Learning Boost- How Threading works in Boost > //How to pass parameters to functions in packaged_task > #define BOOST_THREAD_USE_LIB > #include <iostream> > #include <cstdlib> > #include <boost/thread.hpp> > #include <boost/date_time/posix_time/posix_time.hpp> > using namespace std; > > vector<int> SharedResource; > boost::shared_mutex sharedMutex; > > int FillSharedResource() > { > int numberOfItems=10; > for (int i = 0; i< numberOfItems; i++) > { > boost::unique_lock<boost::shared_mutex> lock(sharedMutex); > SharedResource.push_back(i); > lock.unlock(); > } > return 10; > } > > int Print1() > { > for (int i = 0; i< SharedResource.size(); i++) > { > boost::this_thread::sleep(boost::posix_time::seconds(1)); > boost::lock_guard<boost::shared_mutex> locker(sharedMutex); > cout<<boost::this_thread::get_id()<<"\tItem: > "<<SharedResource[i]<<endl; > } > return 101; > } > > int Print2() > { > for (int i = 0; i< SharedResource.size(); i++) > { > boost::this_thread::sleep(boost::posix_time::seconds(1)); > boost::lock_guard<boost::shared_mutex> locker(sharedMutex); > cout<<boost::this_thread::get_id()<<"\tItem: > "<<SharedResource[i]<<endl; > } > return 102; > } > > int main() > { > > boost::packaged_task<int> > pkg0(FillSharedResource), > pkg1(Print1), > pkg2(Print2); > > boost::thread > t0(ref(pkg0)), > t1(ref(pkg1)), > t2(ref(pkg2)); > > boost::unique_future<int> > f0(pkg0.get_future()), > f1(pkg1.get_future()), > f2(pkg2.get_future()); > > std::cout<< f0.get()<<"\n"<< f1.get()<< "\n"<< f2.get(); > > system("pause"); > return 0; > } > ------------------------- can someone show me a simple sample of using Promise in threading ? i mean i already know about future , whats the need for Promise ? ! -------------------------- whats the different between read_some and async_read_some ? in asio ? -------------------------- i know that when i need to send an argument to event handler ( signal ) , i frist should declare sth like this : > *boost::signal2::signal <function-return-type (paramerter type)> mysignal > ;* > *mysignal**.connect(myfunc,my-functions-argumant)*; > *mysignal**.connect(myfunc2,my-function2s-argumant)*; > now if i have couple of functions with the same signature , doing different jobs with different arguments , how can i give their respective arguments ? i mean at the moment , i can only write : mysignal(5);! and this passes 5 to all functions connected with this signal! do i really have to make one signal for each functions ?so that i can pass different and yet with the same type argument to different functions using one signal . is'nt there any other way around it ? if inside a signal , i run a thread and then i block that signal using signal.block , would that block that thread too ? and then unblocking it would it unblock that thread too ? is it safe doing this ? --------------------------- why do we use function names with const that the end of it ? i mean sth like this : > void operator()() const > { > } > or > void boostFunctionName(sth) const > { > } > what is that const for ? what does it declare ? why is it necessary to use it that way ? -------------------- how do i serialize a class of mine ? i mean i read that if i have vector , i need to use some functions , if i have foo i need another function ! what exactly do you serialize your classes ? i mean maybe i have std::string , char , vectors of some kind , and a self made class or type used in my class to be serialized , how should i go about it . any guidance is greatly appreciated . --------------------- i tired to use boost::container::vector for storing my threads , and it went just fine . but i have a problem in determining which thread is which , i mean i already found out that i can use if-else for this matter , but since i used a vector , and the number of threads being created at run-time is not known , so i need to use a for statement so that i can iterate throuh all of th evectors items and then if i find a match , i do as i wish . the problem is , when i try to have sth like this , it fails : > boost::id id = myvect[0] > i want to pass this id for matching operation ( or declare it as global ) , what am i missing again ? another problem i have in this regard is that , when i store my threads in a lets say vector just like the sample i gave earlier , it is not guaranteed that threads inside that vector actually points to a legal thread of execution by the time i go to check for sth .!( i mean there is a good chance that they already ran and got terminated!) seemingly i can not use joinable to see if i am dealing with an active or lets say legitimate thread ! , my question is , how can i check to see if an object of type thread , actually points to sth real ? how to check that ? --------------------- when i try to compile source codes using Asio using MingW , i get linking errors ! what is the cause and how can i fix that ? i get the errors: > C:\boost_1_49_0\boost\asio\detail\impl\winsock_init.ipp|39|undefined > reference to `WSAStartup@8'| > C:\boost_1_49_0\boost\asio\detail\impl\winsock_init.ipp|48|undefined > reference to `WSACleanup@0'| > Thank you all in advance Seyyed Hossein Hasan Pour

3 7

Problem with asych_write() when sending more than 65536 bytes data on Solaris
by Ranadheer 16 Apr '12

16 Apr '12

We are observing one weird problem when sending message of size more than 65536 bytes using boost asynch_write on Solaris (though the problem is not observed on Linux). We are using boost version 1.47 with studio 12 CC compiler (on Solaris) and g++ 4.4.3 (on Linux). When a message of size more than 65536 (sometimes we are observing the issue with around 50K bytes size also but with 65536 bytes the issue is always reproducible) is sent, the message is delivered correctly to the receiver. But once the message is sent, the io service thread on the sender side goes into busy-wait loop. "truss" on the sender pid shows the following calls continuously. /6: recvmsg(57, 0xFFFFFD7FEB9FDDF0, 0) Err#11 EAGAIN /6: write(13, " 9\0\0\019\0\0\0", 8) = 8 /6: ioctl(13, DP_POLL, 0xFFFFFD7FEB9FE460) = 1 /6: recvmsg(57, 0xFFFFFD7FEB9FDDF0, 0) Err#11 EAGAIN /6: write(13, " 9\0\0\019\0\0\0", 8) = 8 /6: ioctl(13, DP_POLL, 0xFFFFFD7FEB9FE460) = 1 /6: recvmsg(57, 0xFFFFFD7FEB9FDDF0, 0) Err#11 EAGAIN /6: write(13, " 9\0\0\019\0\0\0", 8) = 8 /6: ioctl(13, DP_POLL, 0xFFFFFD7FEB9FE460) = 1 /6: recvmsg(57, 0xFFFFFD7FEB9FDDF0, 0) Err#11 EAGAIN /6: write(13, " 9\0\0\019\0\0\0", 8) = 8 /6: ioctl(13, DP_POLL, 0xFFFFFD7FEB9FE460) = 1 /6: recvmsg(57, 0xFFFFFD7FEB9FDDF0, 0) Err#11 EAGAIN /6: write(13, " 9\0\0\019\0\0\0", 8) = 8 /6: ioctl(13, DP_POLL, 0xFFFFFD7FEB9FE460) = 1 "lsof" shows that the socket descriptor 57 above is the socket descriptor corrected to the receiver. Thread 6 here is the ioservice thread whose stack trace is - thread t@6 -- ???????? thread_proxy boost::detail::thread_data<>::run des::tunnel::ServiceScheduler::processServiceWork boost::asio::io_service::run boost::asio::detail::task_io_service::run boost::asio::detail::task_io_service::do_one boost::asio::detail::dev_poll_reactor::run The busy-wait loop continues until we stop the receiver. Also, as mentioned, the issue is always reproducible if the size of the message more than 65536 (2^16) bytes and sender and receiver are running on 2 different Solaris hosts. If both sender and receiver are running on same Solaris host then the issue is always reproducible with size 131067 (2^17). Can someone throw some light on why the ioservice thread here is continuously trying to read from the receiver though it has successfully sent the message and receiver is not actually writing anything on the socket. Please let me know if anyone came across this problem or suggest any solution. Thanks Ranadheer -- View this message in context: http://boost.2283326.n4.nabble.com/Problem-with-asych-write-when-sending-mo… Sent from the Boost - Users mailing list archive at Nabble.com.

1 1

How to terminate a specific thread among other threads
by Master 15 Apr '12

15 Apr '12

Hello all . i have been trying to selectively dispose a thread among some other threads , but so far i wasnt successful in finding a way to do it . suppose i have a simple function which identifies any threads which gets into it and if a specific one is located ,it is disposed . simply sth like this : #include <boost/signal.hpp> #include <iostream> #include <boost/thread.hpp> using namespace std; boost::thread threadarray[3]; int t(int x) { boost::id id(); switch(boost::this_thread::get_id()) { case threadarray[0].get_id(): cout<<"thread 1"; break; case threadarray[1].get_id(): * DISPOSE THIS THREAD or CHANGE OWNERSHITP, OR GET ANOTHER JOB TO IT , OR CHECK IF IT WAS SUCCESSFUL OR NOT* break; case threadarray[3].get_id(): cout<<"thread 3"; break; default: cout<<"default"; } return 0; } int main() { boost::thread t1(t,5), t2(t,6),t3(t,7); threadarray[0] = t1.move(); threadarray[1] = t2.move(); threadarray[2] = t3.move(); for(int i = 0; i <3;i++) { threadarray[i].join(); } system("pause"); } i cant either use a switch statement to identify which thread im dealing with at the moment , nor can i find any means to keep track of my threads , and manage them in situations like this ( i already tried vector(boost::thread> my vect; and tries to use std::for_each(vect.begin(),vect.end(),somefunction_accepting boost::thread) , this doesnt work !! ) any idea how i can achieve sth similar? Thanks in advance

3 13

[Boost State Chart] Where to include, where to declare?
by Philipp Bender 15 Apr '12

15 Apr '12

Hi all, today I face some major problems with the state charts. Mostly this comes from incorrect forward declarations and so on. I use this scheme for e.g. decaring a state which has orthogonal substates. I hope my pseudocode is readable. ############# Outer.h ############## struct Inner1 struct Inner2 struct Outer < Context, InnerDefaults< Inner1, Inner2> > { // implementation } #include Inner1 // this is the really important part #include Inner2 ############## Inner(1|2).h ######## struct Inner(1|2) < Outer > { // implementation } ################################# Doing so, I am able to use Outer in the Inner files without including something and so on -- but as soon as I start to create a file called "Inner1.cpp" and only write '#include "Inner.h" ' the problems start and the compiler complains that "Outer" ist not declared (what is true I guess). What works is to include the "Outermost" which is the state machine in my case ... but this would mean that every state knows about my state machine. Also, in my approach the cpp files need to be recompiled completely every time I think also if only the header of a completely unrelated state changes (because each cpp includes the complete state chain). So ... what's the suggested way to go? I'd like to have as little dependencies as possible, so not "all_forward_declarations.h" or some such. I had it like that, and it was a big mess. And I like the states to be separated ... Best regards, Philipp

2 1

Set fusion::vector value with boost::shared_ptr
by Stefan Troeger 15 Apr '12

15 Apr '12

Hello alltogether, I've posted this already in Stackoverflow a week ago with no answer up to now, so I thougth I try it here again. I want to set a value in a fusion::vector at a specific location. This works normaly very well with fusion::at_c(seq) = value, as at_c returns a reference to the object at this position. However, this is not garanted, the documentation only states about the return type: "In most cases, this is a reference". I've encounterd a case where it is not a reference, when the objects are of type boost::shared_ptr<anytype>. Therefore I cant set the values as I'm only overriding a temporary. Minimal example: struct Object1{}; struct Object2{}; typedef fusion::vector<boost::shared_ptr<Object1>, boost::shared_ptr<Object2> > seq_type; seq_type seq; boost::shared_ptr<Object1> value(new Object1()); fusion::at_c<0>(seq) = value; assert(fusion::at_c<0>(seq) ); //assert will be executed because the default constructed empty pointer was not overridden with a valid one BOOST_MPL_ASSERT(( boost::is_reference< result_of::at_c<seq_type, 0>::type > )) //compilation fails because the returned type is not a reference What is a valid alternative of setting the pointers in an fusion sequence? Any help would be appreciated! Thanks, Stefan

2 2

[Boost] List of not header-only libraries (requiring linking).
by Klaim - Joël Lamotte 14 Apr '12

14 Apr '12

Hi, I was looking on the website about a list of the boost libraries that require linking/ are not header only. Is it correct that this list is what I'm looking for? http://www.boost.org/doc/libs/?view=filtered_autolink If it is, then I think the name is misleading. Automatic linking happens only with visual studio, right? Also, autolink doesn't really mean anything in this context, so maybe something like "Linking Required" would be better? I also found the list I was looking for there: http://www.boost.org/doc/libs/1_49_0/more/getting_started/windows.html But I had to remember it was there to find it. So I think that people wanting to know this don't go on this page first, they will look at some filter in the library list pages instead. Making it more clear would be helpful, in my opinion. Joël Lamotte

1 0

Open Source Credit Rating Tool Using Boost
by Marc Joffe 14 Apr '12

14 Apr '12

I am looking for users and developers interested in collaborating on an open source sovereign rating model project. If you don't agree with your country's credit rating, here is a chance to do something about it! A pre-release version of the tool is available at http://www.publicsectorcredit.org/pscf.html. Source will be posted to GitHub on 2 May 2012. The tool uses a Monte Carlo simulation which includes calls to Boost's normal and Cauchy random number generators. There are many opportunities for improvement upon the initial version. A blog post explaining the need for this project can be found at: Rating Agency Models and Open Source http://expectedloss.blogspot.com/2012/04/credit-rating-agency-models-and-ope n.html Please contact me if interested. Regards, Marc Joffe Public Sector Credit Solutions marc(a)publicsectorcredit.org

1 0

[Fwd: Error while typecasting the boost::variant ( need help)]
by Baba Prasad 13 Apr '12

13 Apr '12

Dear Friend due to hurry I did sent proper error message so pls have look now. my program is typedef std::vector<std::string> vec_name; struct network { boost::variant<vec_name> net_id; }; typedef std::vector<network>network_list; // create the instance for vector network_list net_list; for(int i=0; i<net_list.size(); ++i) { unsigned char* query_str = net_list[0].net_id; } ERROR is error: cannot convert boost::variant<std::vector<std::basic_string<char> > > to unsigned char* in assignment Best Regards BaBu -- This message has been scanned for viruses and dangerous content by MailScanner, and is believed to be clean.

2 1