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[Interprocess] How to interrupt interprocess_condition::wait()?
by wright_left 23 Mar '12

23 Mar '12

I had a simple concurrent queue that was working fine shuffling data between threads. Now I want to use it between processes. I switched out the boost::condition_variable for a boost::interprocess::interprocess_condition. The queue funcitons normally, except that I can't interrupt the thread waiting on the queue. Previously I simply called boost::thread::interrupt() and the thread would die (with the interrupt exception I assume). But interprocess_condition::wait() doesn't seem to care about the interrupt. Am I missing something? Do I need to use the interprocess_condition since the queue is in shared memory? Or can I go back to using the boost::condition_variable? -- View this message in context: http://boost.2283326.n4.nabble.com/Interprocess-How-to-interrupt-interproce… Sent from the Boost - Users mailing list archive at Nabble.com.

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problems with boost bind and boost thread
by Marco 23 Mar '12

23 Mar '12

Hi, I have problems with the attached code (test.cpp, extracted from the original class only with the relevant code). The member template constructor of CCycleThread takes an argument and passes this to boost bind. The binding is to a another member template method which is the thread function for boost thread: boost::thread(boost::bind(&CCycleThread::execute<T>,this,t) The template parameter type is deduced by the argument type passed by the user. If the type is an ordinary function the code works fine. If the argument itself is another boost bind object the compilation fails! I tested the following within the constructor: auto test = boost::bind(&CCycleThread::execute<T>,this,t) // -> ok test(); // -> compile error The call of the operator() of the bind object is the problem. Interestingly, if one binding is boost::bind and the other one is std::bind the code works. Any ideas what's the problem? How can I fix this? Using std and boost bind is more a hack than a real solution :/

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Clarification on McGregor common subgraph library
by Suhas Chakravarty 22 Mar '12

22 Mar '12

Hi The documentation for the mcgregor common subgraph library, at http://www.boost.org/doc/libs/1_48_0/libs/graph/doc/mcgregor_common_subgrap…, says that " "mcgregor_common_subgraphs_maximum_unique(...); Explores the *entire* search space and invokes the user_callback afterward with each of the largest, unique discovered subgraphs. Returning false from the user_callback will *not* terminate the search because it is invoked after the search has been completed. " Given graph 1 A |__ B_| (Self loop on B) | C / \ D E \ / F | G / \ \ H \ / I And graph 2 A |__ B_| (Self loop on B) | C | D | E / \ \ F \ / G The application of mcgregor_common_subgraphs_maximum_unique gives me the following mapping: G1 <-> E2 H1 <-> F2 I1 <-> G2 But in addition, I was also expecting the mappings A1<-A2, B1<->B2 and C1<-E2, D1<-F2, since these are separate, maximum subgraphs I see these (along with other smaller subgraphs) when I use simply "mcgregor_common_subgraphs" or "mcgregor_common_subgraphs_unique". Why do I not see them with the "maximum" version? Thanks Suhas

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[mpi] all_reduce and MPI_IN_PLACE like feature
by Alain O Miniussi 22 Mar '12

22 Mar '12

Hi, MPI_Allreduce offers the possibility to use the same buffer for the send and recv data: http://www.open-mpi.org/doc/v1.4/man3/MPI_Allreduce.3.php#toc8 It seems that boost's all_reduce does not allow such a feature. First, I would like to know if the previous statement is correct and, if yes, if it was just overlooked or if there was a reason for that? Just in case, I filed a ticket regarding that issue, along with a tentative patch, in https://svn.boost.org/trac/boost/ticket/6704 Regards, Alain

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Convert asio::error_code into boost::system::error_code
by Jens Weller 22 Mar '12

22 Mar '12

Hi, I'm in a usecase, where we use a library, which brings its own asio lib with it: http://www.resiprocate.org/ReTurn_Overview If this is correct, they're using asio 1.2 in its header only version. I've build an API which uses boost::asio to send data over the network. One of our goals is now, to also include stun/turn, so we have to use this library. To enable the errorreporting, I need to convert the asio::error_code coming from reTurn to boost::system::error_code, so that I can call my notify method with it: void notifyError(const boost::system::error_code& ec); any expierence in this? The constructors don't seem to fit, as error_category is in asio a enum, and in boost::system a class f.e. gz Jens Weller -- 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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[Property Map] given a function/functor, how to construct readable property map?
by Frank Birbacher 22 Mar '12

22 Mar '12

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi! I have graph structure using custom datatypes. An edge weight can be calculated by calling some function. I want to call the dag shortest path algorithm and pass it a property map that uses the function to compute edge weights on the fly. I consulted the Boost 1.47 documentation for property map. I find identity or std::map adaptors, but did not find any reference to using functions or functors. Do I miss anything? Frank -----BEGIN PGP SIGNATURE----- Version: GnuPG/MacGPG2 v2.0.17 (Darwin) Comment: GPGTools - http://gpgtools.org Comment: keyserver x-hkp://pool.sks-keyservers.net iEYEARECAAYFAk9o2GwACgkQhAOUmAZhnmpdAwCfc38fjB2cZC/ZYzv7Y8+GXdTr IXgAnjoJh5ZKoxFkNTAK5Ye0DeOkuQY0 =8xTO -----END PGP SIGNATURE-----

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Boost ASIO cancelling jobs from another thread
by Mark Christiaens 21 Mar '12

21 Mar '12

We are developing a client-server application using Boost ASIO for asynchronous socket communication. We were wondering whether it is safe to cancel a read on a socket by closing the socket from another thread (without any additional synchronization)? What would be the preferred way to cancel operations from different threads? Thanks in advance, Mark Christiaens Amplidata

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boost::interprocess managed_unique_ptr cannot be used inside template (VS2008).
by bear330 21 Mar '12

21 Mar '12

Hi, I eagerly want to try boost 1.49, but the compiler error stuck me. managed_unique_ptr cannot be used inside template if I use Visual Studio 2008: There is a very simple example: #include <iostream> #include <boost/interprocess/managed_windows_shared_memory.hpp> #include <boost/interprocess/smart_ptr/unique_ptr.hpp> #include <boost/interprocess/allocators/allocator.hpp> #include <boost/interprocess/containers/list.hpp> #include <boost/interprocess/sync/named_mutex.hpp> #include <boost/interprocess/sync/named_condition.hpp> #include <boost/interprocess/sync/scoped_lock.hpp> struct Request { int a; }; template<typename Segment, typename T> class Channel { public: /// Value pointer in queue. typedef typename boost::interprocess::managed_unique_ptr<T, Segment>::type ValuePtr; }; int main(int argc, char* argv[]) { Channel<boost::interprocess::managed_windows_shared_memory, Request>::ValuePtr v; std::cout << "Test" << std::endl; return 0; } I got this error in Visual Studio 2008: T.cpp C:\Program Files\boost\boost_1_49_0\boost/interprocess/detail/pointer_type.hpp(64) : error C2039: 'remove_reference' : is not a member of 'boost::interprocess::ipcdetail::ipcdetail' C:\Program Files\boost\boost_1_49_0\boost/interprocess/smart_ptr/unique_ptr.hpp(94) : see reference to class template instantiation 'boost::interprocess::ipcdetail::pointer_type<T,D>' being compiled with [ T=Request, D=boost::interprocess::deleter<Request,boost::interprocess::segment_manager<char,boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family>,boost::interprocess::iset_index>> ] T.cpp(34) : see reference to class template instantiation 'boost::interprocess::unique_ptr<T,D>' being compiled with [ T=Request, D=boost::interprocess::deleter<Request,boost::interprocess::segment_manager<char,boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family>,boost::interprocess::iset_index>> ] C:\Program Files\boost\boost_1_49_0\boost/interprocess/detail/pointer_type.hpp(64) : error C2947: expecting '>' to terminate template-argument-list, found '<' C:\Program Files\boost\boost_1_49_0\boost/interprocess/detail/pointer_type.hpp(64) : error C3203: 'remove_reference' : unspecialized class template can't be used as a template argument for template parameter 'D', expected a real type C:\Program Files\boost\boost_1_49_0\boost/interprocess/detail/pointer_type.hpp(64) : error C2955: 'boost::interprocess::ipcdetail::remove_reference' : use of class template requires template argument list C:\Program Files\boost\boost_1_49_0\boost/interprocess/detail/type_traits.hpp(30) : see declaration of 'boost::interprocess::ipcdetail::remove_reference' C:\Program Files\boost\boost_1_49_0\boost/interprocess/detail/pointer_type.hpp(64) : error C2143: syntax error : missing ';' before '>' C:\Program Files\boost\boost_1_49_0\boost/interprocess/detail/pointer_type.hpp(64) : error C2039: 'type' : is not a member of '`global namespace'' C:\Program Files\boost\boost_1_49_0\boost/interprocess/detail/pointer_type.hpp(64) : error C2039: 'type' : is not a member of '`global namespace'' C:\Program Files\boost\boost_1_49_0\boost/interprocess/detail/pointer_type.hpp(64) : error C2238: unexpected token(s) preceding ';' C:\Program Files\boost\boost_1_49_0\boost/interprocess/smart_ptr/unique_ptr.hpp(94) : error C2039: 'type' : is not a member of 'boost::interprocess::ipcdetail::pointer_type<T,D>' ................ This example works fine in boost 1.48.0 I submit a ticket ( https://svn.boost.org/trac/boost/ticket/6648 #6648 ) to boost::interprocess, but no any reply since 3 weeks ago, So I just ask how to solve this problem or any direction? Thanks. -- View this message in context: http://boost.2283326.n4.nabble.com/boost-interprocess-managed-unique-ptr-ca… Sent from the Boost - Users mailing list archive at Nabble.com.

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Metric_TSP_approx example
by Jeff Wang 20 Mar '12

20 Mar '12

Hello, I am looking at metric_tsp_approx.cpp example file to test the TSP issue. My vertex points: 0(0.68,2.72),1(1.69,1.13),2(2.78,2.29),3(1.02,2.47),4(0.83,0.71),5(2.59,0.52) The metric_tsp_approx_tour give the result: 0,3,1,2,4,5,0. I think 0,3,1,2,5,4,0 is better than the previous result, am I wrong? Also, I do not want to have the result like connecting vertex 2 and 4, so I added a larger edge_weight value, say 1000.0 between 2 and 4, but the result is the same as that of genneral vertext distance weight, how could I make the tsp tour does not go from 2 to 4? Thanks, Jeff

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[Boost::Python] ensuring destructors are called when executing scripts
by Andy Falanga (afalanga) 20 Mar '12

20 Mar '12

Hi everyone, I'm working on an API that will be used in Python. I'm running some of my teams unit tests to test some new functionality. (These use the Python unit test framework though I admit I don't understand it.) The exposed class has an "interface" among its many member fields. This abstract class is, I believe, correctly defined. That is, the abstract class defines a virtual destructor. The derived classes define non-virtual destructors. When I use a smaller test python script that doesn't use the unit test framework for Python, all of these destructors seem to be called correctly. However, when using the unit test framework, this doesn't seem to be the case. I believe this to be problem anyway because when I use the unit test scripts, I get a BSOD. (The BSOD is because these classes use a propriety driver that was written by our team for underlying hardware.) When I call this class directly, in my other script, the destructors are called properly because things work and there's no BSOD. I found a posting to some python support group where someone was having a similar problem. They mentioned that using Py_Finalize seemed to fix this but that it shouldn't be used with Boost. I'd like to know what's going on first of all. I'm not a python "anything". Before now, I've never used the language. Is there some way to ensure that C++ destructors are called? One of the respondents to the thread I mentioned said something about the interpreter still hold references and using a clear() method. However, the code he/she provided to illustrate wasn't python code at all but C++. It was as if they didn't understand the OP's request. Any help is greatly appreciated. Andy

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