June 2012 - Boost-users - lists.boost.org

[interprocess] Determine size of managed_shared_memory
by Kai Benndorf 12 Oct '19

12 Oct '19

Hi all, I want to create a managed_shared_memory in exactly the size I needed. Therefore I do something like this: size = sizeof( common_managed_shared_memory ); size += sizeof( MyClassInSharedMem ); managed_shared_memory segment(create_only, "name", size ); MyClassInSharedMem allocates itself some memory by segment->allocate(). I added this also to the size, but get a boost::interprocess::bad_alloc exception on allocating this additional memory. Are there some magic bytes I forgot to add? Many thanks in advance Kai

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[statechart] Passing parameters from event to State Local Storage
by Christophe Bourez 16 Nov '16

16 Nov '16

I need to maintain a parameter into the state local storage. This parameter is initially contained in the event that causes the transition to the target state. I give hereafter a small illustrative example. typename sc = boost::statechart; class EvTest : public sc::event<EvTest> { public: EvTest(std::size_t val) : value(val) {} std::size_t getValue() const { return this->value; } private: std::size_t value; }; class MyStateMachine; class StSource; class StTarget; class StSource : public sc::simple_state<StSource, MyStateMachine> { public: typedef sc::custom_reaction<EvTest> reactions; sc::result react(const EvTest &event) { // How to pass event.getValue() to the target state ? transit<StTarget>(); } }; class StTarget : public sc::simple_state<StTarget, MyStateMachine> { public: StTarget(std::size_t val) : val(value) {} private: std::size_t value; }; Thanks, Christophe

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Statechart serialization
by mbrodeur65 04 Mar '15

04 Mar '15

Hi, I'm looking for a solution to serialize boost::statechart objects. I'm aware that this feature is on the statechart library todo list but was wondering if there are any workaround to achieve this with the latest boost release (1.34) ? thanks for your help ! mbrodeur65 -- View this message in context: http://www.nabble.com/Statechart-serialization-tf4131326.html#a11749139 Sent from the Boost - Users mailing list archive at Nabble.com.

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[Thread] Read-write locks
by lfrfly＠icqmail.com 17 Sep '14

17 Sep '14

I'm trying to create a standard read/write lock using Boost Threads, and I'm having a bit of difficulty mapping the Boost concepts onto the usual ones. A read/write lock should have several states: Locked for reading (multiple threads may lock at once), locked for writing (only one thread may lock, and no threads may be locked for reading at the same time), and unlocked. Ideally it would be nice if an RWL which is locked for reading may temporarily upgrade to locked for writing, then return to the locked for reading state. Boost supports several relevant notions of locking: shared locking, upgrade locking, and exclusive locking. This to me is a confusing distinction. In particular, a shared_mutex seems appropriate as the basis for a RWL, but is lock_upgrade() the equivalent of a write lock and lock_shared the equivalent of a read lock? This is unclear. If "upgrade locking" is not the same as "exclusive locking", then is an upgrade lock actually exclusive? Could someone please clarify this.

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[Statechart] How to decide between post_event and process_event atrun time ?
by Philippe DAVID 22 Jul '14

22 Jul '14

Hi, I have a method in which I want to post/process an event. The thing is, this method can be called from outside the state machine (so I need to call process_event), or indirectly by a reaction of the state machine (in this case I must call post_event since process_event is not reentrant). I don't want to write 2 distinct methods to do this (one that calls post, and the other process), I would much rather prefer adding a 'if' in my method that tells me if I have to call process_event or post_event (if I'm being called indirectly by the state machine or not). Is there a way to do this with statechart ? regards, Philippe

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[asio] resolver::cancel() problem
by Matthew Edwards 14 Mar '14

14 Mar '14

In my application (and a separate test program) it seems as though the cancel() function on the resolver does not work as intended. For async resolves, the cancel functionality should abort them immediately and pass an 'operation aborted' error code to the callback handler. In my tests, I will resolve an invalid domain (this causes the resolve to take a few seconds, to demonstrate the problem), sleep for 100ms, then call cancel on the resolver object. No cancelling actually occurs, and the callback is simply triggered after a few seconds with a "No host found" error code, not the expected operation aborted. Has anyone experienced this before, or know how I might be using the resolver incorrectly?

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[BGL] Having a cost function as weight map
by Maxime van Noppen 06 Sep '13

06 Sep '13

Hi, I can't find how to do this pretty basic thing : having a function instead of a field to compute the cost of edges for various path finding algorithms. I couldn't find the answer in the documentation and Google was of no help. Did I miss something obvious ? Example : ------------------- #include <boost/graph/dijkstra_shortest_paths.hpp> #include <boost/graph/graph_traits.hpp> #include <boost/graph/adjacency_list.hpp> struct my_edge { double cost() const { return cost_ * 2; } double cost_; }; struct my_node { }; int main() { typedef boost::adjacency_list< boost::vecS, boost::vecS, boost::directedS, my_node, my_edge > graph_t; typedef boost::graph_traits<graph_t>::vertex_descriptor vertex_t; graph_t graph; vertex_t v /*= ... */; using boost::weight_map; // Works : boost::dijkstra_shortest_paths(graph, v, weight_map(boost::get(&my_edge::cost_, graph))); // Doesn't compile : //boost::dijkstra_shortest_paths(graph, v, // weight_map(boost::get(&my_edge::cost, graph))); } ------------------- Thanks ! -- Maxime

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Identify cycles in a undirected graph
by NsPx 20 Aug '13

20 Aug '13

Hi all, I use undirected_dfs to detect all cycles in a undirected graph. I detect a cycle with DFSVisitor.back_edge(e,g) but how can I get the list of vertices defining this cycle ? Thanks by advance

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can't get first example in boost tutorial to work
by 7stud 10 Mar '13

10 Mar '13

I'm trying to install boost on mac osx 10.4.7. I followed the tutorial "Getting Started on Unix Variants" found here: http://www.boost.org/doc/libs/1_35_0/ more/getting_started/unix-variants.html Following the instructions in the tutorial, I installed boost in /usr/local as instructed, so my directory structure is: /usr/local/boost_1_34_1/boost But when I run the first example in the tutorial: #include <boost/lambda/lambda.hpp> #include <iostream> #include <iterator> #include <algorithm> int main() { using namespace boost::lambda; typedef std::istream_iterator<int> in; std::for_each(in(std::cin), in(), std::cout << (_1 * 3) << " " ); } I get the error(among others): error: boost/lambda/lambda.hpp: No such file or directory If I change the include path to: #include </user/local/boost_1_34_1/boost/lambda/lambda.hpp> I get the error(among others): error: boost/lambda/core.hpp: No such file or directory But core.hpp is in the lambda directory: /usr/local/boost_1_34_1/boost/lambda$ ls algorithm.hpp control_structures.hpp lambda.hpp bind.hpp core.hpp loops.hpp casts.hpp detail numeric.hpp closures.hpp exceptions.hpp switch.hpp construct.hpp if.hpp I'm using the Xcode 2.4 IDE to run my C++ programs. I also tried to execute the program from the command line with the original include path: #include <boost/lambda/lambda.hpp> but I get the same error: ~/2testing/dir1$ g++ prog1.cpp prog1.cpp:1:35: error: boost/lambda/lambda.hpp: No such file or directory prog1.cpp: In function 'int main()': prog1.cpp:8: error: 'boost' has not been declared prog1.cpp:8: error: expected namespace-name before ';' token prog1.cpp:8: error: '<type error>' is not a namespace prog1.cpp:11: error: '_1' was not declared in this scope I get the same errors again with the full include path: #include </user/local/boost_1_34_1/boost/lambda/lambda.hpp> $ g++ prog1.cpp In file included from prog1.cpp:1: /usr/local/boost_1_34_1/boost/lambda/lambda.hpp:14:33: error: boost/lambda/core.hpp: No such file or directory /usr/local/boost_1_34_1/boost/lambda/lambda.hpp:21:52: error: boost/lambda/detail/operator_actions.hpp: No such file or directory /usr/local/boost_1_34_1/boost/lambda/lambda.hpp:22:61: error: boost/lambda/detail/operator_lambda_func_base.hpp: No such file or directory /usr/local/boost_1_34_1/boost/lambda/lambda.hpp:23:63: error: boost/lambda/detail/operator_return_type_traits.hpp: No such file or directory /usr/local/boost_1_34_1/boost/lambda/lambda.hpp:26:45: error: boost/lambda/detail/operators.hpp: No such file or directory /usr/local/boost_1_34_1/boost/lambda/lambda.hpp:30:46: error: boost/lambda/detail/member_ptr.hpp: No such file or directory prog1.cpp: In function 'int main()': prog1.cpp:8: error: 'boost' has not been declared prog1.cpp:8: error: expected namespace-name before ';' token prog1.cpp:8: error: '<type error>' is not a namespace prog1.cpp:11: error: '_1' was not declared in this scope What path should I be using? Or, should I set an environment variable somewhere?

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[units] Missing quantity operator++, operator%
by Nathan Crookston 25 Oct '12

25 Oct '12

All, I'm in the process of switching my homegrown units system over to boost units. Some operators which I'm missing are the modulus and the pre and post increment operators. Looking through the archives I note an original review[1] which mentioned the absence of those operators. One response claimed that quantity<si::length, int> t = 5. ...; t++; was nonsensical as writing 5 m + 1, and the reviewer eventually agreed, citing possible confusion if the quantity type converted the initializer. Matthias Schabel seemed to respond favorably: 'I debated this for a while - the only problem is that there will be some value types with heterogeneous operator+ / operator- for which q + 1 is not the same type as q, but I guess that it is just OK for it to just give a compile error in those cases.' And Steven Watanabe said 'Will do.' I haven't found anything regarding the modulus operator. My question is, would a patch adding those operators be accepted? Thanks, Nate [1] http://lists.boost.org/Archives/boost/2007/03/119001.php

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Asio and ZeroMQ
by Matthias Vallentin 10 Oct '12

10 Oct '12

A while ago, Maciej Gajewski started an effort to use Asio to observe a ZeroMQ socket [1]. Based on his code, I put together a thin library that wraps the implementation details. Since other have requested a working example, here it is now at github: https://github.com/mavam/bmq Any feedback is highly appreciated. A basic usage example looks like this: #include <boost/asio/io_service.hpp> #include <bmq.h> int main() { boost::asio::io_service io; bmq::context ctx(1); bmq::component c(ctx, io); auto sink = c.add_sink(ZMQ_PAIR, "inproc://x"); c.subscribe(sink, [](bmq::message&& msg) { std::string str(static_cast<char*>(msg.data()), msg.size()); std::cout << str << std::endl; }); auto source = c.add_source(ZMQ_PAIR, "inproc://x"); bmq::message msg(const_cast<char*>("foo"), 3, nullptr); source->send(msg); // Execute message handler. io.poll(); return 0; } At this point, the library is really thin and only provides very rudimentary wrapping of ZeroMQ. In the future, I plan to extend it in order to facilitate applications that build on message-passing. The dataflow abstraction I envision is essentially a directed graph, where nodes represent components and edges communication links. 0mq provides the edges and the Asio handles asynchronous event processing at the component level. The motiviation is that this model lends itself well for scaling out distributed systems over large clusters. Matthias [1] http://permalink.gmane.org/gmane.network.zeromq.devel/9538

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[Sandbox - endian] Why is endian still in sandbox?
by Nathaniel J Fries 07 Oct '12

07 Oct '12

A fairly novel (at least when put up against more intricate labours like asio, filesystem, and their like) project which appears to be finished and would be a very useful companion to existing libraries sits in the sandbox. Is there a reason for this?

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[BGL] vecS for vertex container and vertex index adjustments
by Sergey Mitsyn 03 Oct '12

03 Oct '12

Hi all, I know that while using vecS for vertices one has no vertex iterator stability upon removing vertices. But I have a question if there exists something like vertex _index_ stability. The documentation says that indices for vertices are automatically adjusted so that they are still in contiguous range, but it is not specified how it is done. Is it okay to assume that if a vertex with an index I is removed, then vertices with indices < I have their indices unchanged, while vertices with indices > I have their indices decreased by one? The actual problem is removing all vertices meeting some condition. Is the following code ok? // traverse all vertices and remove those for which predicate // condition_to_remove_vertex returns true. // graph is adjacency_list<.., vecS, ...> vertex_iterator vi = vertices(graph).first, vi_end = vertices(graph).second; while (vi != vi_end) { if (condition_to_remove_vertex(vi, graph)) { vertices_size_type end_index = vertex_index[*vi_end] , vi_index = vertex_index[*vi]; remove_vertex_f(*vi, graph); // vi and vi_end are invalid --end_index; vi = vertices(graph).first + vi_index; vi_end = vertices(graph).first + end_index; // now vi and vi_end are valid again } else ++vi; } This way seems to be more effective than to start iteration again every time a vertex is removed. ------------ Sergey Mitsyn.

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[Range] insert algorithm fails if target is a map
by Robert Jones 10 Sep '12

10 Sep '12

The title says it all really. The failure occurs because the insert algorithm expects the container to provide a 3-arg insert of the form container.insert( position, begin, end ); whereas map's, multimap's and set's insert method only takes two arguments... map.insert( begin, end ); Is this limitation by design? It would be easy to provide specialisations for maps, mmaps and sets, but that would not be a completely general solution. - Rob.

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filesystem directory_iterator run-time error during construction after upgrading to OSX Lion
by Martin Searancke 04 Sep '12

04 Sep '12

I have just upgraded my Mac to Lion and code that worked fine under snow leopard is giving me a run-time exception when constructing a directory_iterator. The error I am getting is "malloc: pointer being freed was not allocated" The line in question that raises this error is: for ( directory_iterator itr( my_path ); itr != end_itr; ++itr ) taken directly from the example and working fine under windows. This is version 1.49 installed with MacPorts. Is this a known problem? I found some vague references to a similar problem in an earlier version of boost but no solution. I have confirmed that I only have 1 copy of the headers and libs on the system and in the correct path. The date stamp on the files matches the last time I did a macports update so this should be the matching library for the header. Please note that I am a real novice to Mac development and have only just started porting code from windows for less than a month. Thanks in advance, Martin

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[Graph] compilation error under Windows but not under Linux
by Gaël de Chalendar 29 Aug '12

29 Aug '12

Hello, I have a compilation error under Windows (Visual C++ 2008) with a code that works well under Linux (gcc 4.6.1 and before). The compilation error is: =========== /FsaAccess16.tcc(833) : error C2784: 'std::pair<graph_traits<G>::in_edge_iterator,graph_traits<G>::in_edge_iterator> boost::in_edges(graph_traits<G>::vertex_descriptor,const boost::subgraph<Graph> &)'ÿ: impossible de d‚duire l'argument modŠle pour 'const boost::subgraph<Graph> &' … partir de 'FrCeaLic2m::Common::FsaAccess::selected_graph_types16::spareGraphType' C:\PROGRA~1\boost\BOOST_~1\boost/graph/subgraph.hpp(432)ÿ: voir la d‚claration de 'boost::in_edges' Z: \Projets\MoteurMultimedia\mm_common\src\common/FsaAccess/FsaAccess16.tcc(778)ÿ: lors de la compilation de la fonction membre '<Inconnu>' de la classe <Inconnu> z: \projets\moteurmultimedia\mm_common\src\common\fsaaccess\FsaAccessReader16.h(118)ÿ: voir la r‚f‚rence … l'instanciation de la classe modŠle 'FrCeaLic2m::Common::FsaAccess::FsaAccess16<graphType>' en cours de compilation with [ graphType=FrCeaLic2m::Common::FsaAccess::selected_graph_types16::spareGraphType ] z: \projets\moteurmultimedia\mm_common\src\common\fsaaccess\FsaAccessSpare16.h(35)ÿ: voir la r‚f‚rence … l'instanciation de la classe modŠle 'FrCeaLic2m::Common::FsaAccess::FsaAccessReader16<graphType>' en cours de compilation with [ graphType=FrCeaLic2m::Common::FsaAccess::selected_graph_types16::spareGraphType ] =========== The line that does not compile is boost::tie(iei,ie_end) = boost::in_edges(commonTarget,m_graph); The function being compiled is declared like that: template <typename graphType > std::pair< const typename boost::graph_traits<graphType>::vertex_descriptor, bool > FsaAccess16<graphType>::findEquivalentInRegister( dicoVertexType tempState ){ ... And here graphType, the type of m_graph is spareGraphType defined by: struct selected_graph_types16 { ... typedef boost::adjacency_list<boost::vecS, boost::vecS, boost::directedS, dicoVertexCountProperty> spareGraphType; ... This is a cmake based project that I compile using qtcreator. I'm a Linux developer and I'm a little bit lost with VC outputs and tools under Windows... Regards, Gaêl -- Gael de Chalendar CEA LIST Centre de Fontenay-aux-Roses Laboratoire Vision et Ingénierie des Contenus (Vision and Content Engineering Laboratory) Bat. 38-2 ; 18, rue du Panorama ; BP 6 92265 Fontenay aux Roses Cedex ; France Tél.:01.46.54.80.18 ; Fax.:01.46.54.75.80 Email : Gael.D.O.T.de-Chalendar.A(a)T.cea.D.O.T.fr

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Re: [Boost-users] asio HTTP Server 3 example memory leak
by admin＠thefireflyproject.us 25 Aug '12

25 Aug '12

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eos_portable_archive for 1.49
by Paul Harris 13 Jul '12

13 Jul '12

Hi all, Does anyone know if eos_portable_archive is still actively used and maintained? It doesn't compile with boost 1.49, and before I try to fix it up, I was wondering if anyone else has fixed it up. cheers Paul

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[bgl] depth_first_search does not compile. color_map howto?
by Joachim Faulhaber 04 Jul '12

04 Jul '12

Hi, When using visitors with the depth_first_search algorithm I can successfully compile and run this code: //========================================================= template<class Graph> class Visitor: public default_dfs_visitor { public: typedef typename graph_traits<Graph>::vertex_descriptor Vertex; void discover_vertex(Vertex v, const Graph& g)const {cout << v << " "; return;} }; void GLV_visit() { typedef adjacency_list<listS, vecS, directedS> GraphLV; GraphLV g; add_edge(0, 1, g); add_edge(0, 2, g); add_edge(1, 2, g); add_edge(1, 3, g); Visitor<GraphLV> vis; boost::depth_first_search(g, visitor(vis)); cout << endl; } BOOST_AUTO_TEST_CASE(graph_test) { GLV_visit(); } //========================================================= With a slightly different graph (listS instead of vecS for vertices) the same call of depth_first_search fails to compile with msvc-10. //========================================================= struct Int{ Int(): _value(0){} Int(int val): _value(val){} int _value; }; void GLL_visit() { typedef adjacency_list<listS, listS, directedS, Int> GraphLL; typedef graph_traits<GraphLL>::vertex_descriptor VertexLL; GraphLL g; Int val(42); VertexLL v0 = boost::add_vertex(g); VertexLL v1 = boost::add_vertex(g); g[v0] = Int(0); g[v1] = Int(1); add_edge(v0, v1, g); Visitor<GraphLL> vis; boost::depth_first_search(g, visitor(vis)); //compile errors } //========================================================= >From the tiny error message of 108 long verbose lines of internal graph template instantiations (see attachment) it seems that the compiler is unable to create a default color_map (but I might be wrong with this interpretation of the template jungle). 1. Do I need to provide a color_map parameter here? 2. If so, what is the simplest way to do that and provide an object of the appropriate type? I'd greatly appreciate a working code example. Examples and best practices for defining and handling external propery maps in general would be helpful. TIA, Joachim -- Interval Container Library [Boost.Icl] http://www.joachim-faulhaber.de

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[statechart] history in the different state hierarchies
by Vlad Orlov 02 Jul '12

02 Jul '12

Hello everybody. I have a problem similar to the one described in the Statechart tutorial, but a little different. My state machine has two states (let's call them A and B) in the different state hierarchies and a third state C that can be transited to from either A or B. The transition from C must be done to either A or B, depending on where we came to C from. So I've decided to use the history. The difference between this problem and what's described in the tutorial is that A and B don't belong to the same composite state (they only belong to the same state machine). I can't simply declare "has_xxx_history" in the outer state like it's done in the tutorial. Here's what I've tried to do: #include <iostream> #include <boost/statechart/shallow_history.hpp> #include <boost/statechart/simple_state.hpp> #include <boost/statechart/state_machine.hpp> #include <boost/statechart/transition.hpp> namespace sc = boost::statechart; // events struct transfer_to_B : sc::event<transfer_to_B> {}; struct visit_C : sc::event<visit_C> {}; struct exit_to_history : sc::event<exit_to_history> {}; // forward declarations struct state_A; struct substate_A; struct substate_B; struct state_C; // state machine struct test_fsm : sc::state_machine<test_fsm, state_A> {}; // composite state A struct state_A : sc::simple_state<state_A, test_fsm, substate_A, sc::has_shallow_history> {}; struct substate_A : sc::simple_state<substate_A, state_A> { typedef boost::mpl::list < sc::transition<transfer_to_B, substate_B> , sc::transition<visit_C, state_C> > reactions; substate_A() { std::cout << "Entered A" << std::endl; } ~substate_A() { std::cout << "Exited A" << std::endl; } }; // composite state B struct state_B : sc::simple_state<state_B, test_fsm, substate_B, sc::has_shallow_history> {}; struct substate_B : sc::simple_state<substate_B, state_B> { typedef sc::transition<visit_C, state_C> reactions; substate_B() { std::cout << "Entered B" << std::endl; } ~substate_B() { std::cout << "Exited B" << std::endl; } }; // simple state C struct state_C : sc::simple_state<state_C, test_fsm> { typedef sc::transition < exit_to_history, sc::shallow_history<substate_A> > reactions; state_C() { std::cout << "Entered C" << std::endl; } ~state_C() { std::cout << "Exited C" << std::endl; } }; int main() { test_fsm fsm; fsm.initiate(); fsm.process_event(visit_C()); fsm.process_event(exit_to_history()); fsm.process_event(transfer_to_B()); fsm.process_event(visit_C()); fsm.process_event(exit_to_history()); } Unfortunately, this doesn't work as intended. The transition to history always leads to substate_A and never to substate_B: Entered A Exited A Entered C Exited C Entered A Exited A Entered B Exited B Entered C Exited C Entered A Exited A Can anyone please clarify if I've got something wrong or made a mistake somewhere? Is history supposed to work in the different state hierarchies?

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Program Options: What would be involved in implementing add_options()(optionNameWork, po::value<std::pair<int, float>>() ?
by Charles Mills 30 Jun '12

30 Jun '12

I really like Boost Program Options. I came up with this wild hare of being able to handle something like foo= int float Obviously, I could do it by instead using foo_int= int foo_float= float But what would be involved in being able to do something like add_options()(optionNameWork, po::value<std::pair<int, float>>() ? I would have to derive a class from boost::program_options::value_semantic? I would have to implement all of the abstract methods? The other classes also like abstract_variables_map? Or just variable_value? Volodya wrote in response to an earlier question "I would imagine this to be not hard. Either define operator>> for the class you use to represent rectangles, over override 'validate'" Is that what I should? Define operator>> for pair<int, float> ? Where is an example of a boost::program_options >> operator? Where is validate() declared? Sorry to be such a newbie at this level of C++ programming. You have to start somewhere. Charles

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Re: [Boost-users] [boost] Meeting C++ - Call for Papers
by Jens Weller 30 Jun '12

30 Jun '12

Hi, small update on this: As some people haved asked: The session length will be 45 minutes, some talks might extend to 90 min. There is now a form to submit your talk: http://meetingcpp.com/index.php/submit-your-talk.html Call for Papers should end at 15. July 2012 Tickets will also be available in July. regards, Jens Weller -------- Original-Nachricht -------- > Datum: Wed, 27 Jun 2012 16:45:54 +0200 > Von: Matus Chochlik <chochlik(a)gmail.com> > An: boost(a)lists.boost.org > Betreff: [boost] Meeting C++ - Call for Papers > On Wed, Jun 27, 2012 at 4:08 PM, Jens Weller <JensWeller(a)gmx.de> wrote: > > Dear C++/boost community! > > > > I'm proud to announce the call for papers for the Meeting C++ > conference! > > After having talked to some people in Aspen about the plans for a C++ > conference in Germany, I've decided to give it a try. > > Meeting C++ will take place in November in Germany, as a 2 Day C++ > conference. > > > > Thank You for organizing this conference! -- 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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[1.50.0] Boost release 1.50.0 available
by Beman Dawes 29 Jun '12

29 Jun '12

Release 1.50.0 of the Boost C++ Libraries is now available. These open-source libraries work well with the C++ Standard Library, and are usable across a broad spectrum of applications. The Boost license encourages both commercial and non-commercial use. This release contains four new libraries (Algorithm, Functional/OverloadedFunction, LocalFunction and Utility/IdentityType) and numerous enhancements and bug fixes for existing libraries. For details, including download links, see http://www.boost.org/users/news/version_1_50_0 You can also download directly from SourceForge: http://sourceforge.net/projects/boost/files/boost/1.50.0/ To install this release on your system, see http://www.boost.org/doc/libs/release/more/getting_started/index.html Thanks, --The Boost release team Beman Dawes Daniel James Eric Niebler Marshall Clow Rene Rivera Vladimir Prus

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[Boost.Python] Is it possible classes X Y returned each other?
by Sergiy Nazarenko 29 Jun '12

29 Jun '12

Hi, all! I'm writing python module and run into obstacle. I need a couple of classes which can return instance of each other. This is part of my module: /// mysupermodule.cpp ... struct X { X():s("default") {} X(std::string s):s(s) {} Y getY() const { return Y(); } }; struct Y { Y():s("default") {} Y(std::string s):s(s) {} X getX() const { return X(); } }; ... /// And I got obvious error: mysupermodule.cpp:45:5: error: ‘Y’ does not name a type. How can I solve this task? Regards Sergiy

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boost 1.50 different libraray naming?
by Szymon Gatner 29 Jun '12

29 Jun '12

Hi, I just build v 1.50 on Win 7 / Visual Studio 2008 SP1 (msvc9) and I am getting linker errors like: Error 21 fatal error LNK1104: cannot open file 'libboost_filesystem-vc90-mt-gd-1_50.lib' test test because in this release files are named without "90" part: libboost_filesystem-vc-mt-gd-1_50 while in 1.49 (and below): libboost_exception-vc90-mt-gd-1_49 Regards, Szymon Gatner

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[ptr_container] Regression: ptr_multimap breaks Wextra build in version 1.49.0
by Philipp Münzel 29 Jun '12

29 Jun '12

Hi fellows, I'm using gcc 4.2.1 on OSX 10.7.4 and I've recently updated from boost 1.47 to 1.49.0. My project uses ptr_multimaps. My project is configured to use the gcc flags -Werror -Wall -Wextra because I like to be alerted early if something can go wrong. Using -Werror is kind of a self-imposed restriction to keep my code clean of dirty hacks. I've been used to compile my code this way since about boost 1.44. With the update to 1.49 however, building with -Werror -Wextra is no longer possible, because I'm getting the following warning: /usr/local/boost/include/boost/ptr_container/ptr_map_adapter.hpp: In copy constructor 'boost::ptr_multimap_adapter<T, VoidPtrMultiMap, CloneAllocator, Ordered>::ptr_multimap_adapter(const boost::ptr_multimap_adapter<T, VoidPtrMultiMap, CloneAllocator, Ordered>&) [with T = Foo, VoidPtrMultiMap = std::multimap<std::basic_string<char, std::char_traits<char>, std::allocator<char> >, void*, std::less<std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::allocator<std::pair<const std::basic_string<char, std::char_traits<char>, std::allocator<char> >, void*> > >, CloneAllocator = boost::heap_clone_allocator, bool Ordered = true]': /usr/local/boost/include/boost/ptr_container/ptr_map.hpp:89: instantiated from here /usr/local/boost/include/boost/ptr_container/ptr_map_adapter.hpp:727: warning: base class 'class boost::ptr_container_detail::ptr_map_adapter_base<Foo, std::multimap<std::basic_string<char, std::char_traits<char>, std::allocator<char> >, void*, std::less<std::basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::allocator<std::pair<const std::basic_string<char, std::char_traits<char>, std::allocator<char> >, void*> > >, boost::heap_clone_allocator, true>' should be explicitly initialized in the copy constructor The only possibility to compile this is to remove -Wextra, because gcc has no separate warning option to turn off the copy constructor check (see [1]), so I lose not only this check, but also everything else enabled by -Wextra, which I'd be very unhappy with. For the time being, I just removed -Werror, but this totally clutters up my build output now, which usually allows me to spot every problem really quick, because it is so brief. Since this is a regression (it worked until the 1.49.0 update), I'd be happy if someone can check how this was introduced in 1.49.0 and open a ticket for the incriminating change. Regards, Philipp [1] http://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html

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Re: [Boost-users] Visual Studio Express
by Tom Kent 28 Jun '12

28 Jun '12

Last I checked, the express editions of visual studio (vc8,vc9,vc10) wouldn't build all the debugging info into libraries. I just went searching on Microsoft's website, but couldn't find anywhere that spells out what is/isn't included with the express versions. Beyond that, there have been announcements that the VC11 express version wasn't going to be able to make non-metro apps. I think they have gone back on this, but it still sounds like it will be limited. I haven't looked into this issue for a few years, so it is quite likely that I'm wrong. I'd love to hear from someone with better knowledge on this issue. Tom On Thu, Jun 28, 2012 at 12:52 PM, David Sankel <camior(a)gmail.com> wrote: > On Thu, Jun 28, 2012 at 10:13 AM, Tom Kent <lists(a)teeks99.com> wrote: > >> I've built windows libraries (vc8, vc9, vc10) for this (32 and 64 >> bit), if you want them, you can get them from my website: >> http://boost.teeks99.com >> >> I'm also looking for a donation of VC11 when it comes out (express won't >> work). >> > > Why won't express work? > > David > > -- > David Sankel > Sankel Software > www.sankelsoftware.com > > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users >

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self-referential boost functions
by Adam Crain 28 Jun '12

28 Jun '12

Inquiring as to whether this is possible or if there is a better pattern for simulating this behavior... Is it possible for boost::function to be self referential? I.e. how do I simulate behavior like the following: typedef boost::function<Func (int)> Func; A function that does something mutable and then returns the next function to be called or an empty function. thanks, Adam

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Re: [Boost-users] compilation error using boost/property_tree/ptree.hpp
by Pramod Subramanyan 28 Jun '12

28 Jun '12

Thanks for the tip, Lars. That was indeed the problem - one of the libraries we are using was defining a fail macro. Pramod

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compilation error using boost/property_tree/ptree.hpp
by Pramod Subramanyan 28 Jun '12

28 Jun '12

I am trying to use boost/property_tree/ptree.hpp in my application. All I have done so far is just add the following include statements to my program: > #include <boost/property_tree/ptree.hpp> > #include <boost/property_tree/xml_parser.hpp> After adding these lines, I compiled my modified application using g++ 4.6.3 on Ubuntu 12.04. I get the following errors: g++ -c -Wall -Werror -I../cudd-2.4.2//include/ -I /home/pramod/libraries/boost_1_50_0/ -O2 -Wno-unused-result -Wno-unused-function -c -o main.o main.cpp In file included from /home/pramod/libraries/boost_1_50_0/boost/property_tree/ptree.hpp:17:0, from main.h:10, from main.cpp:17: /home/pramod/libraries/boost_1_50_0/boost/property_tree/stream_translator.hpp: In static member function ‘static void boost::property_tree::customize_stream<Ch, Traits, bool, void>::extract(std::basic_istream<_CharT, _Traits>&, bool&)’: /home/pramod/libraries/boost_1_50_0/boost/property_tree/stream_translator.hpp:117:18: error: expected unqualified-id before ‘{’ token /home/pramod/libraries/boost_1_50_0/boost/property_tree/stream_translator.hpp:117:18: error: expected ‘)’ before ‘{’ token /home/pramod/libraries/boost_1_50_0/boost/property_tree/stream_translator.hpp: In member function ‘boost::optional<E> boost::property_tree::stream_translator<Ch, Traits, Alloc, E>::get_value(const internal_type&)’: /home/pramod/libraries/boost_1_50_0/boost/property_tree/stream_translator.hpp:191:20: error: expected unqualified-id before ‘{’ token /home/pramod/libraries/boost_1_50_0/boost/property_tree/stream_translator.hpp:191:20: error: expected ‘)’ before ‘{’ token make: *** [main.o] Error 1 When I look the lines117 and 191 in ptree.hpp, they are the following: s >> e; if(s.fail()) { // Try again in word form. and customized::extract(iss, e); if(iss.fail() || iss.bad() || iss.get() != Traits::eof()) { return boost::optional<E>(); I can't spot anything obviously wrong with either of these lines. Does anyone have any clues on what could be going wrong? Thanks! Pramod

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Anyone following boost as a git submodule?
by Chris Cleeland 28 Jun '12

28 Jun '12

Is anyone tracking boost for their project(s) as a git submodule by chance? What we've done up 'til now is import a particular boost rev directly into our repo (actually an SVN repo) but that is sub-optimal for various reasons. We're in the process of transitioning to git, so using a git submodule becomes a possibility. Wondering if anybody is doing that and, if so, if they'd be willing to discuss their experience either on list or privately. -- Chris Cleeland

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[Interprocess] Unable to Access More than 7 GB of Memory
by Hering Cheng 27 Jun '12

27 Jun '12

Hi, Using Boost.Interprocess, with either unmanaged or managed shared memory, I am unable to access beyond 7 GB of the 20 GB of memory I allocated, despite the fact that none of the Interprocess API calls returned any error or threw any exception. I run into segmentation fault when I actually try to access the portion of the memory above the (approximately) 7 GB limit. If I perform a similar test with shared memory constructed via manual calls to System V IPC, then I can access all of the 20 GB of memory without any problem. I suspect this may be due to mmap() (using by Interprocess along with POSIX shm_open() and other calls) but I have been unable to verify. Does anyone have any experience on this? The machine is running RedHat 5 with 16 GB of RAM. (Yes, when I go through the 20 GB of memory a lot of paging/swapping occurred.) From below, I do not think that the problem was due to configuration. $ uname -a Linux NJ-CEL01 2.6.18-164.11.1.el5 #1 SMP Wed Jan 6 13:26:04 EST 2010 x86_64 x86_64 x86_64 GNU/Linux $ ulimit -a core file size (blocks, -c) 2147483648 data seg size (kbytes, -d) unlimited scheduling priority (-e) 0 file size (blocks, -f) unlimited pending signals (-i) 141312 max locked memory (kbytes, -l) 32 max memory size (kbytes, -m) unlimited open files (-n) 1024 pipe size (512 bytes, -p) 8 POSIX message queues (bytes, -q) 819200 real-time priority (-r) 0 stack size (kbytes, -s) 10240 cpu time (seconds, -t) unlimited max user processes (-u) 141312 virtual memory (kbytes, -v) unlimited file locks (-x) unlimited $ grep . /proc/sys/kernel/shm* /proc/sys/kernel/shmall:4294967296 /proc/sys/kernel/shmmax:68719476736 /proc/sys/kernel/shmmni:4096 $ getconf PAGE_SIZE 4096 The following is the code for the test cases. struct entry_t { uint64_t f[10]; }; BOOST_FIXTURE_TEST_CASE(sysv_ipc, fixture) { std::cout << "System V IPC shared memory" << std::endl; const std::string shm_key = "/proc/sys/kernel/shmall"; const std::size_t shm_size = 20L * 1024L * 1024L * 1024L; const key_t ipc_key = ftok(shm_key.c_str(), 0); const int rm_rc = shmctl(ipc_key, IPC_RMID, NULL); if (rm_rc < 0) { std::cerr << "Unable to remove shared memory: " << strerror(errno) << std::endl; } const int shm_id = shmget(ipc_key, shm_size, 0644 | IPC_CREAT | IPC_EXCL); BOOST_ASSERT_MSG(shm_id >= 0, strerror(errno)); void * const shm_addr = shmat(shm_id, NULL, 0); BOOST_ASSERT_MSG(shm_addr != reinterpret_cast<void *>(-1), strerror(errno)); const std::size_t entry_count = 90L * (shm_size / sizeof(entry_t)) / 100L; entry_t * array = reinterpret_cast<entry_t *>(shm_addr); std::cout << "Initializing " << entry_count << " entries..." << std::endl; for (std::size_t i = 0; i < entry_count; ++i) { entry_t & entry = array[i]; void * addr = & entry; new (addr) entry_t(); if (i % 1000000 == 0) { std::cout << i << std::endl; } } std::cout << "Initialized all entries" << std::endl; shmctl(ipc_key, IPC_RMID, NULL); } BOOST_FIXTURE_TEST_CASE(unmanaged, fixture) { std::cout << "Unmanaged shared memory" << std::endl; const std::string shm_key = "test"; const std::size_t shm_size = 20L * 1024L * 1024L * 1024L; bipc::shared_memory_object::remove(shm_key.c_str()); bipc::shared_memory_object shm_obj(bipc::create_only, shm_key.c_str(), bipc::mode_t::read_write, bipc::permissions(0666)); shm_obj.truncate(shm_size); bipc::mapped_region region(shm_obj, bipc::read_write); const std::size_t entry_count = 90L * (shm_size / sizeof(entry_t)) / 100L; entry_t * array = reinterpret_cast<entry_t *>(region.get_address()); for (std::size_t i = 0; i < entry_count; ++i) { entry_t & entry = array[i]; void * addr = & entry; new (addr) entry_t(); if (i % 1000000 == 0) { std::cout << i << std::endl; } } bipc::shared_memory_object::remove(shm_key.c_str()); } BOOST_FIXTURE_TEST_CASE(managed, fixture) { std::cout << "Managed shared memory" << std::endl; const std::string shm_key = "test"; const std::size_t shm_size = 20L * 1024L * 1024L * 1024L; bipc::shared_memory_object::remove(shm_key.c_str()); bipc::managed_shared_memory shm(bipc::create_only, shm_key.c_str(), shm_size); typedef bipc::managed_shared_memory::allocator<entry_t>::type allocator_t; allocator_t array_alloc(shm.get_segment_manager()); const std::size_t entry_count = 90L * (shm_size / sizeof(entry_t)) / 100L; allocator_t::pointer array_ptr = array_alloc.allocate(entry_count); entry_t * array = array_ptr.get(); for (std::size_t i = 0; i < entry_count; ++i) { entry_t & entry = array[i]; void * addr = & entry; new (addr) entry_t(); if (i % 1000000 == 0) { std::cout << i << std::endl; } } bipc::shared_memory_object::remove(shm_key.c_str()); } Thanks. Hering

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Meeting C++ - Call for Papers
by Jens Weller 27 Jun '12

27 Jun '12

Dear C++/boost community! I'm proud to announce the call for papers for the Meeting C++ conference! After having talked to some people in Aspen about the plans for a C++ conference in Germany, I've decided to give it a try. Meeting C++ will take place in November in Germany, as a 2 Day C++ conference. We are looking for speakers and possible talks at our conference in fall! Possible topics could include: * (modern) C++ * C++11 * boost * C++ Frameworks like Qt, wxWidgets, Ogre, ... * other C++ related topics You'll find more information and updates at the webpage http://meetingcpp.com Tickets will be available from July at our website. regards, Jens Weller -- NEU: FreePhone 3-fach-Flat mit kostenlosem Smartphone! Jetzt informieren: http://mobile.1und1.de/?ac=OM.PW.PW003K20328T7073a

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boost asio crash
by 陈海峰 27 Jun '12

27 Jun '12

quote_server[5071] general protection rip:904f96 rsp:2aaacd41fe70 error:0 [root@linuxdev quoteserver]# addr2line -e quote_server 904f96 /usr/local/boost_1_49_0/include/boost/asio/detail/epoll_reactor.hpp:111

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boost asio crash, how to solve
by 陈海峰 27 Jun '12

27 Jun '12

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[Boost.Function] detecting ignored arguments?
by Christoph Duelli 27 Jun '12

27 Jun '12

I have a callback-interface that can optionally process a "ServerError". If the callback looks at the error, there should be no default processing of the error. I have created a class callback that accepts two kinds of Boost.Functions: one with, one without an error object. When passing a callback function that does not look at the error, the call is ambiguous: both Boost.Functions could accept it. Is there a way to work around that problem? Can callback detect what kind of function it was passed? Some code illustrating my question: #include <boost/function.hpp> class ServerError; template<typename T> struct callback { typedef boost::function<void(T)> cb_func; cb_func callback_; typedef boost::function<void(T,const ServerError&)> cb_err_func; cb_err_func callback_err_; callback(const cb_func &cb) : callback_(cb) {} callback(const cb_err_func &cb) : callback_err_(cb) {} }; static void xxx(int) {} int main (int argc, char **argv) { // does not compile: ambiguous... callback<int> cb(&xxx); // does compile: but I'd like the compiler (or my lib) to automatically pick // the right one callback<int> cb(callback<int>::cb_func(&xxx)); return 0; } In the meantime I have found a possible workaround: If I change typedef boost::function<void(T,const ServerError&)> cb_err_func; to typedef boost::function<void(const ServerError&,T)> cb_err_func; the code does compile. Best regards and thank you for looking into this Christoph

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Using boost string algorithm with BOOST_NO_STD_LOCALE
by Allan Nielsen 26 Jun '12

26 Jun '12

Hi, I'm developing for an embedded environment where we do not have a complete c++ standard library available, and one of the things missing is std::locale. But even without this feature, I would very much like to use the boost string algorithms ( split, tokenize, etc ). The only problem is that they depends on std::locale. I have been looking around in the source code, trying to see how easy it would be to add the needed ifdef's to make it work without std::locale. Most of the code looks straight forward to modify, but I'm stuck on this function: struct is_classifiedF : public predicate_facade<is_classifiedF> { // Boost.ResultOf support typedef bool result_type; // Constructor from a locale is_classifiedF(std::ctype_base::mask Type, std::locale const & Loc = std::locale()) : m_Type(Type), m_Locale(Loc) {} // Operation template<typename CharT> bool operator()( CharT Ch ) const { return std::use_facet< std::ctype<CharT> >(m_Locale).is( m_Type, Ch ); } private: std::ctype_base::mask m_Type; std::locale m_Locale; }; I know what the code does, I just do not know how it does it. This is without a doubt because I know nothing about locale, facet, etc. What I would like is another version of this struct which did not depend on std::locale, but simply assumed that the local used is "C". Something like this: struct is_classifiedF : public predicate_facade<is_classifiedF> { typedef bool result_type; is_classifiedF(std::ctype_base::mask Type) : m_Type(Type) {} template<typename CharT> bool operator()( CharT Ch ) const { // Write something here } private: std::ctype_base::mask m_Type; }; But as I do not understand the meaning/encoding of std::ctype_base::mask m_Type I found it hard to write the missing function body. So I could use some pointers/hints on how to implement this. Thanks Allan W. Nielsen

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Explicit constructing boost intrusive list
by Allan Nielsen 26 Jun '12

26 Jun '12

Hi, I would like to use a boost::intrusive::list as a static global resource, which are accessed by other global objects. To ensure that the list is initialized before it is used by "other" global objects, I have been looking in to using the "Nifty counter" method (http://en.wikibooks.org/wiki/More_C%2B%2B_Idioms/Nifty_Counter) The problem is, that the nifty counter demands that it can control construction and destruction of the object. Is there any achieve this or something similar when using intrusive::list as a global resource? Best regards Allan W. Nielsen

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[serialization] Serializing array of POD or custom type
by Kim Gadecki 26 Jun '12

26 Jun '12

Hi everyone. I'm trying to work out how you serialize arrays using the boost serializer. Here's a simplified example: struct node_link { u32 node_A; u32 node_B; }; struct Node { node_link* m_node_links_array; int m_node_links_size; }; // non-intrusive serialization template<class Archive> void serialize(Archive & ar, node_link& link, const unsigned int version) { ar & link.node_A; ar & link.node_B; } template<class Archive> void serialize(Archive & ar, Node& node_data, const unsigned int version) { ar & boost::serialization::array<node_link>(node_data.m_node_links_array, node_data.m_node_links_size); ar & node_data.m_node_links_size; } This seems to work for serializing but I get an error on de-serialization. Can anyone tell me the correct way to do this? Thanks

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Hello, I meet some complied error, Anybody know how to solve it ?
by mingliang zou 25 Jun '12

25 Jun '12

This is source code: //====== file_dep_graph.h ====== /* #include <iostream> #include <fstream> #include <map> #include <string> #include <vector> #include <iterator> #include <algorithm> #include <numeric> using namespace std; #include <boost/graph/adjacency_list.hpp> #include <boost/tuple/tuple.hpp> #include <boost/graph/properties.hpp> #include <boost/graph/property_iter_range.hpp> using namespace boost; */ //============================== #include "file_dep_graph.h" typedef string Name; typedef float CompileCost; namespace boost { enum vertex_compile_cost_t { vertex_compile_cost = 111 }; BOOST_INSTALL_PROPERTY( vertex, compile_cost ); } typedef adjacency_list< listS, listS, directedS, property<vertex_name_t, Name, property<vertex_compile_cost_t, CompileCost, property<vertex_distance_t, float, property<vertex_color_t, default_color_type> > > >, property<edge_weight_t, float> > file_dep_graph2; typedef graph_traits<file_dep_graph2>::vertex_descriptor vertex_d; typedef graph_traits<file_dep_graph2>::vertex_iterator vertex_i; typedef graph_traits<file_dep_graph2>::edge_descriptor edge_d; typedef graph_traits<file_dep_graph2>::edge_iterator edge_i; typedef property_map<file_dep_graph2, vertex_name_t>::type name_map_t; typedef property_map<file_dep_graph2, vertex_compile_cost_t>::type compile_cost_map_t; typedef property_map<file_dep_graph2, vertex_distance_t>::type distance_map_t; typedef property_map<file_dep_graph2, vertex_color_t>::type color_map_t; typedef map<Name, vertex_d> Name2Vertex; typedef pair<Name, CompileCost> TargetProperties; typedef vector<TargetProperties> TargetsProperties; typedef istream_iterator<TargetProperties> TargetsPropertiesInputIterator; typedef ostream_iterator<TargetProperties> TargetsPropertiesOutputIterator; namespace std { istream& operator>> ( istream& is, TargetProperties& target_propertices ) { is >> target_propertices.first >> target_propertices.second; return is; } ostream& operator<< ( ostream& os, const TargetProperties& target_propertices ) { os << target_propertices.first << ' ' << target_propertices.second; return os; } } typedef pair<Name, Name> Dependency; typedef vector<Dependency> Dependencies; typedef istream_iterator<Dependency> DependenciesInputIterator; typedef ostream_iterator<Dependency> DependenciesOutputIterator; namespace std { istream& operator>> ( istream& is, Dependency& dependency ) { is >> dependency.first >> dependency.second; return is; } ostream& operator<< ( ostream& os, const Dependency& dependency) { os << dependency.first << ' ' << dependency.second; return os; } } template <typename Graph, typename ColorMap, typename Visitor> void dfs_v2( const Graph& g, typename graph_traits<Graph>::vertex_desciptor u, ColorMap color, Visitor vis ) { typedef typename property_traits<ColorMap>::value_type color_type; typedef color_traits<color_type> ColorT; color[ u ] = ColorT::gray(); vis.discover_vertex( u, g ); typename graph_traits<Graph>::out_edge_iterator ei, ei_end; for( tie( ei, ei_end ) = out_edges( u, g ); ei != ei_end; ei++ ) if( color[ target( *ei, g ) ] = ColorT::white() ) { vis.tree_edge( *ei, g ); dfs_v2( g, target( *ei, g ), color, vis ); } else if( color[ target( *ei, g ) ] == ColorT::gray() ) vis.back_edge( *ei, g ); else vis.forward_or_cross_edge( *ei, g ); color[ u ] = ColorT::black(); vis.finish_vertex( u, g ); } template <typename Graph, typename Visitor, typename ColorMap> void generic_dfs_v2( const Graph& g, Visitor vis, ColorMap color ) { typedef color_traits<typename property_traits<ColorMap>::value_type> ColorT; typename graph_traits<Graph>::vertex_iterator vi, vi_end; for( tie( vi, vi_end ) = vertices( g ); vi != vi_end; vi++ ) color[ *vi ] = ColorT::white(); for( tie( vi, vi_end ) = vertices( g ); vi != vi_end; vi++ ) if( color[ *vi ] == ColorT::white() ) dfs_v2( g, *vi, color, vis ); } struct default_dfs_visitor { template <typename V, typename G> void discover_vertex( V, const G& ) {} template <typename E, typename G> void tree_edge( E, const G& ) {} template <typename E, typename G> void back_edge( E, const G& ) {} template <typename E, typename G> void forward_or_cross_edge( E, const G& ) {} template <typename V, typename G> void finish_vertex( V, const G& ) {} }; template <typename OutputIterator> struct topo_visitor : public default_dfs_visitor { topo_visitor( OutputIterator& order ) :topo_order( order ) {} template <typename Graph> void finish_vertex( typename graph_traits<Graph>::vertex_descriptor u, const Graph& ) { *topo_order++ = u; } OutputIterator& topo_order; }; template <typename Graph, typename OutputIterator, typename ColorMap> void topo_sort( const Graph& g, OutputIterator topo_order, ColorMap color ) { topo_visitor<OutputIterator> vis( topo_order ); generic_dfs_v2( g, vis, color ); } int main() { // ====== input data from file ======= ifstream ifile( "makefile_target_properties.dat" ); TargetsPropertiesInputIterator it( ifile ), it_end; TargetsProperties targets_properties( it, it_end ); ifile.close(); ifstream ifile_dep( "makefile_dependencies.dat" ); DependenciesInputIterator it_dep( ifile_dep ), it_dep_end; Dependencies dependencies( it_dep, it_dep_end ); ifile_dep.close(); // ======= create graph ====== file_dep_graph2 g( targets_properties.size() ); vertex_i vi, vi_end; tie( vi, vi_end ) = vertices( g ); Name2Vertex name2vertex; for( int i = 0; vi != vi_end; vi++, i++ ) name2vertex[ targets_properties[ i ].first ] = *vi; for( int i = 0; i < dependencies.size(); i++ ) add_edge( name2vertex[ dependencies[ i ].first ], name2vertex[ dependencies[ i ].second ], g ); // ======== set properties ======== tie( vi, vi_end ) = vertices( g ); name_map_t name_map = get( vertex_name, g ) ; for( int i = 0; vi != vi_end; vi++, i++ ) name_map[ *vi ] = targets_properties[ i ].first; tie( vi, vi_end ) = vertices( g ); compile_cost_map_t compile_cost_map = get( vertex_compile_cost, g ); for( int i = 0; vi != vi_end; vi++, i++ ) compile_cost_map[ *vi ] = targets_properties[ i ].second; graph_property_iter_range<file_dep_graph2, vertex_name_t>::iterator ni, ni_end; tie( ni, ni_end ) = get_property_iter_range( g, vertex_name ); for( ;ni != ni_end; ni++ ) cout << *ni << endl; graph_property_iter_range<file_dep_graph2, vertex_compile_cost_t>::iterator ci, ci_end; tie( ci, ci_end ) = get_property_iter_range( g, vertex_compile_cost ); cout << accumulate( ci, ci_end, 0.0 ) << endl; vector<vertex_d> order( num_vertices( g ) ); color_map_t color_map = get( vertex_color, g ); topo_sort( g, order.rbegin(), color_map ); return 0; } ========= complied code ========= [root@zml file_dep_graph]#g++ -o file_dep_graph2 file_dep_graph2.cpp file_dep_graph2.cpp: In function 'void generic_dfs_v2(const Graph&, Visitor, ColorMap) [with Graph = boost::adjacency_list<boost::listS, boost::listS, boost::directedS, boost::property<boost::vertex_name_t, std::basic_string<char, std::char_traits<char>, std::allocator<char> >, boost::property<boost::vertex_compile_cost_t, float, boost::property<boost::vertex_distance_t, float, boost::property<boost::vertex_color_t, boost::default_color_type, boost::no_property> > > >, boost::property<boost::edge_weight_t, float, boost::no_property>, boost::no_property, boost::listS>, Visitor = topo_visitor<std::reverse_iterator<__gnu_cxx::__normal_iterator<void**, std::vector<void*, std::allocator<void*> > > > >, ColorMap = boost::adj_list_vertex_property_map<boost::adjacency_list<boost::listS, boost::listS, boost::directedS, boost::property<boost::vertex_name_t, std::basic_string<char, std::char_traits<char>, std::allocator<char> >, boost::property<boost::vertex_compile_cost_t, float, boost::property<boost::vertex_distance_t, float, boost::property<boost::vertex_color_t, boost::default_color_type, boost::no_property> > > >, boost::property<boost::edge_weight_t, float, boost::no_property>, boost::no_property, boost::listS>, boost::default_color_type, boost::default_color_type&, boost::vertex_color_t>]': file_dep_graph2.cpp:165: instantiated from 'void topo_sort(const Graph&, OutputIterator, ColorMap) [with Graph = file_dep_graph2, OutputIterator = std::reverse_iterator<__gnu_cxx::__normal_iterator<void**, std::vector<void*, std::allocator<void*> > > >, ColorMap = boost::adj_list_vertex_property_map<boost::adjacency_list<boost::listS, boost::listS, boost::directedS, boost::property<boost::vertex_name_t, std::basic_string<char, std::char_traits<char>, std::allocator<char> >, boost::property<boost::vertex_compile_cost_t, float, boost::property<boost::vertex_distance_t, float, boost::property<boost::vertex_color_t, boost::default_color_type, boost::no_property> > > >, boost::property<boost::edge_weight_t, float, boost::no_property>, boost::no_property, boost::listS>, boost::default_color_type, boost::default_color_type&, boost::vertex_color_t>]' file_dep_graph2.cpp:225: instantiated from here file_dep_graph2.cpp:132: error: no matching function for call to 'dfs_v2(const boost::adjacency_list<boost::listS, boost::listS, boost::directedS, boost::property<boost::vertex_name_t, std::basic_string<char, std::char_traits<char>, std::allocator<char> >, boost::property<boost::vertex_compile_cost_t, float, boost::property<boost::vertex_distance_t, float, boost::property<boost::vertex_color_t, boost::default_color_type, boost::no_property> > > >, boost::property<boost::edge_weight_t, float, boost::no_property>, boost::no_property, boost::listS>&, void*&, boost::adj_list_vertex_property_map<boost::adjacency_list<boost::listS, boost::listS, boost::directedS, boost::property<boost::vertex_name_t, std::basic_string<char, std::char_traits<char>, std::allocator<char> >, boost::property<boost::vertex_compile_cost_t, float, boost::property<boost::vertex_distance_t, float, boost::property<boost::vertex_color_t, boost::default_color_type, boost::no_property> > > >, boost::property<boost::edge_weight_t, float, boost::no_property>, boost::no_property, boost::listS>, boost::default_color_type, boost::default_color_type&, boost::vertex_color_t>&, topo_visitor<std::reverse_iterator<__gnu_cxx::__normal_iterator<void**, std::vector<void*, std::allocator<void*> > > > >&)' How can I solve this error? Anybody can help me?

2 3

[boost::format] operator % could use call_traits<..>::parameter_type
by Luc Bourhis 25 Jun '12

25 Jun '12

Hi, consider a library featuring code like template <..., unsigned Rank, ...> struct Foo { ... static unsigned const rank = Rank; .... }; as well as boost::format(...) % Foo::rank Such code will link if and only if a definition for Foo::rank is provided because the interface of operator % is template <class T> operator%(const T& x) This is not possible in the library, as I do not know which values of Rank will be used by client code. Thus the only possibility is a hat trick like boost::format(...) % (Foo::rank+0) If operator % took integral types by value instead, this would alleviate the problem. Hence the suggestion to use call_traits<T>::parameter_type instead of T const &. Of course, the same could be said of many functions other than format::operator% Best wishes, Luc Bourhis

2 2

Trouble linking with boost::program_options on OSX 10.7
by Jürgen Simon 24 Jun '12

24 Jun '12

Hi, I have boost 1.49 installed through homebrew on OSX 10.7. I'm attempting to compile a program making use of boost::program_options. I get the following error: Undefined symbols for architecture x86_64: "boost::program_options::detail::cmdline::get_canonical_option_prefix()", referenced from: boost::program_options::basic_command_line_parser<char>::run() in meanshift_clustering.o ld: symbol(s) not found for architecture x86_64 clang: error: linker command failed with exit code 1 (use -v to see invocation) I clearly remember that this used to compile in the past. In the meantime I had uninstalled and re-installed boost a few times. I double-checked the invocation though, the paths are correct: Ld Debug/meanshift_clustering normal x86_64 cd myproject setenv MACOSX_DEPLOYMENT_TARGET 10.7 /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang++ -arch x86_64 -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.7.sdk -Lmyproject/Debug -Fmyproject/Debug -filelist myproject/myproject.build/Debug/meanshift_clustering.build/Objects-normal/x86_64/meanshift_clustering.LinkFileList -mmacosx-version-min=10.7 -Wl,-search_paths_first -Wl, -headerpad_max_install_names myproject/Debug/libmyproject.dylib /usr/local/lib/libradolan.dylib /usr/local/lib/libnetcdf_c++.dylib /usr/local/lib/libnetcdf.dylib /usr/local/lib/libboost_system-mt.dylib /usr/local/lib/libboost_program_options-mt.dylib /usr/local/lib/libboost_thread-mt.dylib /usr/local/lib/libhdf5.dylib /usr/local/lib/libhdf5_hl.dylib -o myproject/Debug/meanshift_clustering I checked with nm if the symbol is in /usr/local/lib/libboost_program_options-mt.dylib and it is not. This makes me think it's some kind of problem with boost. I do not reference this symbol in my code directly, anywhere. -- View this message in context: http://boost.2283326.n4.nabble.com/Trouble-linking-with-boost-program-optio… Sent from the Boost - Users mailing list archive at Nabble.com.

2 1

Boost Program Options: Any way to have variable number of "objects" each with parameters?
by Charles Mills 24 Jun '12

24 Jun '12

I really like the Boost Program Options library. I've used it for one program now with great effect and I'd like to use it for another, but can't figure out how to structure what I need to do so that Boost PO could handle it. I am solely interested in the ".ini file" for this - command line is irrelevant. The problem is "how does a program allow the specification of a variable number of 'objects' each of which has parameters of its own?" Here is a hypothetical program that exemplifies the problem. Suppose a program were going to create multiple geometric shapes of some sort. An ideal (unsupported by PO) .ini file might look like rectangles=3 rectangle[0].width=5 rectangle[0].height=10 rectangle[1].width=3 etc. circles=2 circle[0].diameter=4 etc. Can anyone suggest a way to accomplish this with Boost PO? I'm real flexible on what the .ini file might look like so long as it solves the problem and is reasonably explicable to a user. (No need for it to look almost like the above.) Thanks, Charles

3 6

BGL Python lib compilation error.
by vy 24 Jun '12

24 Jun '12

Hi, I am new to BGL as well as python and need to install BGL support for Python. I followed the following steps for the installation. 1. downloaded Boost current : 1.49.0: & bootstrap with --with-python=/usr/bin/python 2. downloaded bgl-python from 'svn co https://svn.osl.iu.edu/svn/projects/viz/bgl-python' 3. set the environ variable BOOST_ROOT to "dir head of Boost1_49_0 src code" 4. run bjam in bgl-python. dir I get 2 compilation errors. ...failed gcc.compile.c++ bin.v2/gcc-4.6/release/graphml.o... ...skipped <pbin.v2/gcc-4.6/release>_graph.so for lack of <pbin.v2/gcc-4.6/release>graphviz.o... ...failed updating 2 targets... ...skipped 1 target... === The errors are related to read/write_graphviz() read/write_graphml() in files graphviz.cpp and graphml.cpp : Anyone who have fixes are work around, kindly please let know. Thanks a lot, in advance. Example error output given below: [1] In file included from src/graphviz.cpp:11:0: 17 boost-python/boost_1_49_0/boost/graph/graphviz.hpp: In function ‘void boost::write_graphviz(std::ostream&, con st Graph&, VertexPropertiesWriter, EdgePropertiesWriter, GraphPropertiesWriter, VertexID, typename boost::enable_if_c<boost::i s_base_and_derived<boost::vertex_list_graph_tag, typename boost::graph_traits<Graph>::traversal_category>::value, boost::graph ::detail::no_parameter>::type) [with Graph = boost::graph::python::basic_graph<boost::undirectedS>, VertexPropertiesWriter = b oost::dynamic_properties, EdgePropertiesWriter = std::basic_string<char>, GraphPropertiesWriter = boost::graph::python::object _as_string_property_map<boost::graph::python::basic_descriptor<void*, boost::undirectedS> >, VertexID = boost::graph::python:: basic_index_map<boost::graph::python::basic_descriptor<void*, boost::undirectedS>, boost::adj_list_vertex_property_map<boost:: adjacency_list<boost::listS, boost::listS, boost::undirectedS, boost::property<boost::vertex_index_t, unsigned int>, boost::pr operty<boost::edge_index_t, unsigned int>, boost::no_property, boost::listS>, unsigned int, const unsigned int&, boost::vertex _index_t> >, std::ostream = std::basic_ostream<char>, typename boost::enable_if_c<boost::is_base_and_derived<boost::vertex_lis t_graph_tag, typename boost::graph_traits<Graph>::traversal_category>::value, boost::graph::detail::no_parameter>::type = boos t::graph::detail::no_parameter]’: 18 boost-python/boost_1_49_0/boost/graph/graphviz.hpp:286:5: instantiated from ‘void boost::write_graphviz(std: :ostream&, const Graph&, VertexPropertiesWriter, EdgePropertiesWriter, GraphPropertiesWriter, typename boost::enable_if_c<boos t::is_base_and_derived<boost::vertex_list_graph_tag, typename boost::graph_traits<Graph>::traversal_category>::value, boost::g raph::detail::no_parameter>::type) [with Graph = boost::graph::python::basic_graph<boost::undirectedS>, VertexPropertiesWriter = boost::dynamic_properties, EdgePropertiesWriter = std::basic_string<char>, GraphPropertiesWriter = boost::graph::python::ob ject_as_string_property_map<boost::graph::python::basic_descriptor<void*, boost::undirectedS> >, std::ostream = std::basic_ost ream<char>, typename boost::enable_if_c<boost::is_base_and_derived<boost::vertex_list_graph_tag, typename boost::graph_traits< Graph>::traversal_category>::value, boost::graph::detail::no_parameter>::type = boost::graph::detail::no_parameter]’ 19 src/graphviz.cpp:105:5: instantiated from ‘void boost::graph::python::write_graphviz(const Graph&, const string&, const stri ng&) [with Graph = boost::graph::python::basic_graph<boost::undirectedS>, std::string = std::basic_string<char>]’ 20 src/graphs.hpp:28:1: instantiated from here 21 boost-python/boost_1_49_0/boost/graph/graphviz.hpp:260:5: error: no match for call to ‘(boost::graph::python:: object_as_string_property_map<boost::graph::python::basic_descriptor<void*, boost::undirectedS> >) (std::ostream&)’

1 0

[range] boost::size wrong return type?
by Oswin Krause 24 Jun '12

24 Jun '12

Hi list, I'm using boost 1.49 and get an annoying number of signed/unsigned comparison warnings when i use boost::size. Which is because the return type seems to be signed When I look at boost/range/size.hpp, i get template<class SinglePassRange> inline BOOST_DEDUCED_TYPENAME range_difference<SinglePassRange>::type <--signed size(const SinglePassRange& rng) But the documentation for random access ranges tells otherwise: Expression: boost::size(a) Return Type: boost::range_size<X>::type and Forward Range defines range_size as: boost::range_size<X>::type An unsigned integral type that can represent any nonnegative value of the Range's distance type. assuming the documentation does not lie, I propose the following fix template<class SinglePassRange> inline BOOST_DEDUCED_TYPENAME range_size<SinglePassRange>::type size(const SinglePassRange& rng) Greetings, Oswin

2 1

boost::wave::context deadlocks when called from a DLL
by Julien Lebot 24 Jun '12

24 Jun '12

Hi all, I'm having some issue with boost::wave::context: I have a function called PreProcessSource, which allocates a boost::wave::context and does some preprocessing; nothing fancy at all. std::string PreProcessSource(const std::string& instring, const std::string& defines) { typedef boost::wave::cpplexer::lex_token<> token_type; typedef boost::wave::cpplexer::lex_iterator<token_type> lex_iterator_type; typedef boost::wave::context<std::string::iterator, lex_iterator_type> context_type; std::string source = instring; context_type ctx(source.begin(), source.end()); // DEADLOCK here ctx.set_language(boost::wave::enable_emit_line_directives(ctx.get_language(), true)); if(!defines.empty()) { std::vector<std::string> tokens; Split<std::string>(defines, tokens, ","); std::vector<std::string>::const_iterator cit = tokens.begin(); for (;cit != tokens.end(); ++cit) ctx.add_macro_definition(*cit); } context_type::iterator_type first = ctx.begin(); context_type::iterator_type last = ctx.end(); std::string outstring; while (first != last) { const token_type::string_type& value = (*first).get_value(); std::copy(value.begin(), value.end(), std::back_inserter(outstring)); ++first; } return outstring; } In the past it used to work fine, albeit with boost 1.47.0: Library Nitro is a DLL that hosts the PreProcess source function, the executable uses the Nitro DLL and can call PreProcess source, and Nitro DLL can also sometimes call the function itself. But right now this is no longer the case: whenever Nitro DLL calls the function itself, or Nitro DLL calls another function, which in turn calls back into Nitro DLL PreProcess function, it deadlocks. If DO_DEADLOCK is defined to 1 in the following piece of code, the deadlock will happen: // In executable class Tutorial01 : public Game { public: // ... Tutorial01() : Game() { #if !DO_DEADLOCK std::stringstream sstream; sstream << "void main(inout float4 vtxInput : POSITION) { }" << std::endl << std::endl; std::string source = sstream.str(); std::string defines = ""; std::string shaderCode = Nitro::PreProcessSource(source, defines); #endif } void LoadContent() { #if DO_DEADLOCK std::stringstream sstream; sstream << "void main(inout float4 vtxInput : POSITION) { }" << std::endl << std::endl; std::string source = sstream.str(); std::string defines = ""; std::string shaderCode = Nitro::PreProcessSource(source, defines); #endif // Original code that deadlocks too. // Calls in the DLL, which will call PreProcessSource. // effect->Initialize(device, source, "DX11"); } // ... }; int APIENTRY wWinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPWSTR lpCmdLine, int nCmdShow) { Tutorial00 app; app.Run(); return 0; } Note that the constructor is called directly from the executable, whereas LoadContent is called from the DLL: // In Nitro DLL void Game::Run() { try { // ... LoadContent(); // ... } catch(/* ... */) { } } The code is compiled for x64 and in debug mode. I compile boost myself into a DLL (using bcp to get the files for the libraries I use) with the following options: Preprocessor: WIN32 BOOST_ALL_NO_LIB BOOST_ALL_DYN_LINK BOOST_THREAD_BUILD_DLL _DLL _DEBUG _WINDOWS _USRDLL Code Generation: C++ Exceptions (/EHsc) Multi-threaded Debug DLL (/MDd) Function-level linking (/Gy) Streaming SIMD Extensions 2 (/arch:SSE2) (/arch:SSE2) Fast floating point model (/fp:fast) DLL A uses the same code gen options, and has the following preprocessor macros defined: _WINDLL _UNICODE UNICODE WIN32 _WINDOWS BOOST_ALL_NO_LIB _DEBUG The executable and unit test executable uses the same code gen options, and have the following preprocessor macros defined: BOOST_ALL_NO_LIB UNICODE _UNICODE _MBCS I have tried various combinations of preprocessor definitions (with _DEBUG and without, with BOOST_THREAD_USE_DLL, and without; to no avail). Here is the (cleaned up) stack trace of the deadlock: ntdll.dll!0000000076dc135a() [Frames below may be incorrect and/or missing, no symbols loaded for ntdll.dll] KernelBase.dll!000007fefd4f10dc() Nitro.dll!boost::call_once<void (__cdecl*)(void)>(boost::once_flag & flag, void (void)* f) Line 197 + 0x18 bytes C++ Nitro.dll!boost::call_once(void (void)* func, boost::once_flag & flag) Line 28 C++ Nitro.dll!boost::spirit::classic::static_<boost::thread_specific_ptr<boost::weak_ptr<boost::spirit::classic::impl::grammar_helper ... Line 72 + 0x13 bytes C++ Nitro.dll!boost::spirit::classic::impl::get_definition<boost::wave::util::time_conversion::time_conversion_grammar, ... Line 241 + 0x17 bytes C++ Nitro.dll!boost::spirit::classic::impl::grammar_parser_parse<0,boost::wave::util::time_conversion::time_conversion_grammar, ... Line 296 + 0xa bytes C++ Nitro.dll!boost::spirit::classic::grammar<boost::wave::util::time_conversion::time_conversion_grammar, ... Line 55 + 0x3c bytes C++ Nitro.dll!boost::spirit::classic::grammar<boost::wave::util::time_conversion::time_conversion_grammar, ... Line 65 + 0x75 bytes C++ Nitro.dll!boost::spirit::classic::impl::phrase_parser<boost::spirit::classic::space_parser>::parse<char const * __ptr64,boost::wave::util::time_conversion::time_conversion_grammar> ... Line 136 C++ Nitro.dll!boost::spirit::classic::parse<char const * __ptr64,boost::wave::util::time_conversion::time_conversion_grammar, ... Line 155 + 0x3a bytes C++ Nitro.dll!boost::spirit::classic::parse<char,boost::wave::util::time_conversion::time_conversion_grammar, ... Line 173 + 0x23 bytes C++ Nitro.dll!boost::wave::util::time_conversion::time_conversion_helper::time_conversion_helper(const char * act_time) Line 123 C++ Nitro.dll!boost::wave::util::predefined_macros::predefined_macros() Line 196 + 0x38 bytes C++ ... Nitro.dll!Nitro::PreProcessSource(const std::basic_string<char,std::char_traits<char>,std::allocator<char> > & instring, const std::basic_string<char,std::char_traits<char>,std::allocator<char> > & defines) Line 51 + 0xa0 bytes C++ Tutorial01.exe!Tutorial01::LoadContent() Line 70 + 0x33 bytes C++ Nitro.dll!Nitro::Game::Run() Line 40 C++ Tutorial01.exe!wWinMain(HINSTANCE__ * hInstance, HINSTANCE__ * hPrevInstance, wchar_t * lpCmdLine, int nCmdShow) Line 149 C++ Tutorial01.exe!__tmainCRTStartup() Line 547 + 0x42 bytes C Tutorial01.exe!wWinMainCRTStartup() Line 371 C kernel32.dll!00000000766a652d() ntdll.dll!0000000076d9c521() It seems boost::wave is trying to parse some time stamp, and by doing so instantiates a grammar and that's when things seem to go bad. The deadlock happens inside the constructor of the context type, and the Visual Studio debugger points me to line 197 in boost\thread\win32\once.hpp BOOST_VERIFY(!::boost::detail::win32::WaitForSingleObject( event_handle,::boost::detail::win32::infinite)); When called directly from the executable, I have noticed that the once_flag.status value is 0, and it exits the loop on the first iteration, whereas when it's called from inside the DLL, the once_flag.status value is 53, and it goes around the loop twice before falling into the WaitForSingleObject. I'm not sure if that's even relevant but I've exhausted all the possibilities and I'm out of ideas. I'd be grateful if anyone could shed some light on this. Best Regards, Julien Lebot

2 3

issue about include boost thread header in MFC dll
by young 23 Jun '12

23 Jun '12

I have a MFC dll application. I try to use Boost thread in the dll. #include "stdafx.h" #include "interface.h" #include "MFCDLL.h" #include <boost/thread.hpp> // The one and only CMFCDLLApp object CMFCDLLApp theApp; EXPORT32 int __stdcall func() { AFX_MANAGE_STATE(AfxGetStaticModuleState()); ... return DLL_OK; } The build is OK. But when I call the func, it crashes. If I comment the line: //#include <boost/thread.hpp> Then it works well. So how to use thread in MFC dll? -- View this message in context: http://boost.2283326.n4.nabble.com/issue-about-include-boost-thread-header-… Sent from the Boost - Users mailing list archive at Nabble.com.

3 5

Filesystem: Choose random file from directory
by Andrej van der Zee 23 Jun '12

23 Jun '12

Hi, I have a directory with about 500.000 thousand small files in it. I need to randomly select one of those file. What would be the *most efficient* way to achieve this? Thank you, Andrej

4 4

[serialization] mingw Deriving from boost::archive::xml_iarchive
by Ken 23 Jun '12

23 Jun '12

Hi, We have a boost archive class derived from boost::archive::xml_iarchive_impl, like this: class XmlInputArchive : public boost::archive::xml_iarchive_impl< XmlInputArchive >, public boost::archive::detail::shared_ptr_helper Its purpose is to provide diagnostics information when deserialising xml archive input, ie. which tag is failing. In porting from 1_41 to 1_49 on mingw this no longer links because the boost::archive::basic_xml_grammar<char> class's symbols are no longer exported from the serialization library. The functions this class overrides are the protected functions: void load_start( const char * name ); void load_end( const char * name ); The existing boost::archive::xml_iarchive class derives from xml_iarchive_impl, and as these functions are protected in the latter, they are not available to a class derived from boost::archive::xml_iarchive class directly. And, for the same reason, we can't create an archive class that delegates to a boost::archive::xml_iarchive instance. So neither deriving from boost::archive::xml_iarchive nor using one as a delegate are feasible solutions. Is there a way of creating an xml_iarchive class that has access to the load_start, load_end functions? Or perhaps there is another way to get the diagnostics information about which xml tags are being processed? Thanks, Ken Appleby

2 2

Advance usage of mutil index,need help.
by 张大千 23 Jun '12

23 Jun '12

this is the story: suppose you have some files(files1,files2,files3) and some usergroup(ug1,ug2,ug3). and this is the struct file{ string name; set<string> group; } and file1.name = "file1"; file1.group.insert("ug1"); file1.group.insert("ug2"); file1.group.insert("ug3"); file2.name = "file2"; file2.group.insert("ug2"); file3.name = "file3"; file3.group.insert("ug3"); and i need search by file name or group, and file name should can be support fuzzy search (eg. *ile , *1 ....) can boost mutil index do this,if can ,what kind index need? or there is other way to do this?

1 0