June 2015 - Boost-users - lists.preview.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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[Range, Phoenix] What am I missing...
by Robert Jones 25 Apr '17

25 Apr '17

Hi Folks Can anyone explain the output of this program... #include <iostream> #include <boost/range/algorithm/copy.hpp> #include <boost/range/counting_range.hpp> #include <boost/range/adaptor/reversed.hpp> #include <boost/range/adaptor/transformed.hpp> #include <boost/phoenix/bind/bind_function.hpp> #include <boost/phoenix/core/argument.hpp> int f( int i ) { return i * 2; } int main( ) { using boost::adaptors::reversed; using boost::adaptors::transformed; using boost::counting_range; using boost::copy; using boost::phoenix::arg_names::_1; copy( counting_range( 1, 5 ) | reversed | transformed( f ), std::ostream_iterator<int>( std::cout, " " ) ); std::cout << std::endl; copy( counting_range( 1, 5 ) | reversed | transformed( bind( f, _1 ) ), std::ostream_iterator<int>( std::cout, " " ) ); std::cout << std::endl; } Which is... 8 6 4 2 1768406272 1768406272 1768406272 1768406272 I'm using Gcc 4.6.2 & Boost 1.53 Thx All.

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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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Re: [Boost-users] Crashing Issue
by swati upadhyaya 04 Nov '15

04 Nov '15

hi I am using like this where RunningThreads_ is vector containing boost thread object pointer(handler).I am using interrupt() for the interruption of thread interruption_point() catching that interruption then joining.everytime its crashing in join() for me but for others who have the same configuration its working fine all of us has windos 8. For me also it was working last week but this week the same piece of code is crashing. :( RunningThreads_[i].handle->interrupt(); RunningThreads_[i].handle->join(); delete RunningThreads_[i].handle; On Thu, Feb 5, 2015 at 9:31 AM, swati upadhyaya <swatiupadhyaya(a)gmail.com> wrote: > RunningThreads_[i].handle->interrupt(); > LOG4CPLUS_INFO(root, "Thread Interrupted for " << > RunningThreads_[i].app_name << " successful"); > RunningThreads_[i].handle->join(); > LOG4CPLUS_INFO(root, "Waiting for thread to exit " << > RunningThreads_[i].app_name << " successful"); > delete RunningThreads_[i].handle; > LOG4CPLUS_INFO(root, "Thread handle for " << > RunningThreads_[i].app_name << " successfully deleted"); > //RunningThreads_.erase(i); > > On Wed, Feb 4, 2015 at 12:10 AM, Vicente J. Botet Escriba < > vicente.botet(a)wanadoo.fr> wrote: > >> Le 03/02/15 09:10, swati upadhyaya a écrit : >> >> In my code join() timed_joined() is crashing, I am using these API >> after interrupt(),Same piece of code is working for others but in my system >> its crashing, >> Is there some dependency problem I am using >> Boost version: 1.55.0 >> OS: Windows 8 >> IDE: Visual Studio 2010 >> >> Hi, >> >> it could help if you post the example and the backtrace. >> >> Which version/OS/compiler use others for which this works? >> >> Vicente >> >> _______________________________________________ >> Boost-users mailing list >> Boost-users(a)lists.boost.org >> http://lists.boost.org/mailman/listinfo.cgi/boost-users >> > >

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the stability of breadth_first_visit in BGL
by breadbread1984 14 Jul '15

14 Jul '15

I am wondering if breadth_first_visit can always get the same sequence of vertex no matter whether the graph is serialized and deserialized again. Thx

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Subgraph at distance n
by Rossano Schifanella 14 Jul '15

14 Jul '15

Hi all, which is the easiest way to extract from a graph G and a generic node source a subgraph with all the vertices/edges at distance at most n from source? Thanks a lot for your help. Best, Rossano

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Problems to use Boost Graph
by Oodini 04 Jul '15

04 Jul '15

Hello, I am trying to understand the boost::dijkstra_shortest_paths() function. I don't understand the second and third arguments. The documentation says they're supposed to be properties map : OUT: predecessor_map(PredecessorMap p_map) The predecessor map records the edges in the shortest path tree, the tree computed by the traversal of the graph. Upon completion of the algorithm, the edges (p[u],u) for all u in V are in the tree. The shortest path from vertex s to each vertex v in the graph consists of the vertices v, p[v], p[p[v]], and so on until s is reached, in reverse order. The tree is not guaranteed to be a minimum spanning tree. If p[u] = u then u is either the source vertex or a vertex that is not reachable from the source. The PredecessorMap type must be a Read/Write Property Map whose key and value types are the same as the vertex descriptor type of the graph. but that doesn't work. I have to use an iterator on the properties map, by using : boost::make_iterator_property_map(pred_map.begin(),vertex_index) Does the documentation need reviewers ?

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Boost 1.58 and Intel Compiler 15
by Matthieu Brucher 02 Jul '15

02 Jul '15

Hi, Has any one worked with the latest Intel compiler on Linux? I'm hit with some Spirit/Fusion issues that don't arise with gcc 4.8.2 or clang 3.6.0. Quite difficult to diminish the number of lines in my example case, as the errors are different between in project and out of project... Cheers, Matthieu -- Information System Engineer, Ph.D. Blog: http://matt.eifelle.com LinkedIn: http://www.linkedin.com/in/matthieubrucher Music band: http://liliejay.com/

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Re: [Boost-users] Boost-users Digest, Vol 4181, Issue 1
by Carl Wallace 01 Jul '15

01 Jul '15

> >Message: 7 >Date: Tue, 30 Jun 2015 11:08:50 +0900 >From: Kohei Takahashi <flast(a)flast.jp> >To: boost-users(a)lists.boost.org >Subject: Re: [Boost-users] fusion error when compiling graphviz code > using VC2010 >Message-ID: <5591FA32.6070802(a)flast.jp> >Content-Type: text/plain; charset="utf-8" > >Hi Carl, > >On 2015/06/29 20:36, Carl Wallace wrote: >> We have been using Boost's graphviz support for several years and have >> upgraded through a few versions of Boost with no issues in some long >> stable code. However, when we moved to 1.58 our Windows build broke. We >> are still using VC2010, with plans to move to 2015 in the >>not-too-distant >> future. We have not yet tried 1.58 in VC2015. The error message is very >> large but emanates from here: >Can I get (minimal) reproducible code or more detailed error log? > >Best, >Kihei This stripped down code snip is enough to trigger the error when the 1.58 code is in place and compiles fine when the code from 1.54 is substituted in the place I indicating initially. This code is not intended to do anything and I have not run it. I can send the original error message if you like too. Will send that privately if you want it. #include <boost/graph/breadth_first_search.hpp> #include <boost/graph/visitors.hpp> #include <boost/graph/graphviz.hpp> using namespace boost; template <class Name, class ColorMap> class label_writer2 { public: label_writer2(Name _name, ColorMap _color) : name(_name), color(_color) {} template <class VertexOrEdge> void operator()(std::ostream& out, const VertexOrEdge& v) const { } private: Name name; ColorMap color; }; struct VertexProps { }; typedef adjacency_list < vecS, vecS, bidirectionalS, VertexProps> graph_t; typedef property_map<graph_t, std::string VertexProps::*>::type name_map_t; int _tmain(int argc, char* argv[]) { std::ostringstream oss; graph_t m_graph; name_map_t m_nameMap; two_bit_color_map<property_map<graph_t, vertex_index_t>::const_type>color_map(num_vertices(m_graph), get(vertex_index, m_graph)); boost::write_graphviz(oss, m_graph, label_writer2<name_map_t, two_bit_color_map<property_map<graph_t, vertex_index_t>::const_type> >(m_nameMap, color_map)); return 0; }

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Thinking in HDF5
by nitin chandra 30 Jun '15

30 Jun '15

Hello All, I have been on this for a long time and have done a lot of research / reading on this topic, HDF5. To use it for development of in-house software for design calculation of various alignments. A lot many time the basic alignment information is picked from a map / satellite imageries. Kilometre, ground level, geographic feature on the proposed route, etc. , in a csv file. Any where between 7-9 files are generated for each alignment. 1. How to read / write data into the HDF5 file ? What after creating root ? 2. In a regular situation, I have 2 input file with 3 column csv data, and 2 output files. How to do that within the same root ? Will be working in Python and c / c++. This is just the basic. If I can do this much, I can do the rest, hopefully :) Thanks to All Nitin PS :- Will post in scipy-user list too.

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fusion error when compiling graphviz code using VC2010
by Carl Wallace 30 Jun '15

30 Jun '15

We have been using Boost's graphviz support for several years and have upgraded through a few versions of Boost with no issues in some long stable code. However, when we moved to 1.58 our Windows build broke. We are still using VC2010, with plans to move to 2015 in the not-too-distant future. We have not yet tried 1.58 in VC2015. The error message is very large but emanates from here: boost/include/boost-1_58\boost/fusion/container/list/cons.hpp(86): error C2664: 'boost::xpressive::detail::alternates_list<Head,Tail>::alternates_list(cons t Head &,const boost::fusion::nil &)' : cannot convert parameter 1 from 'const boost::fusion::cons_iterator<Cons>' to 'const boost::xpressive::detail::static_xpression<Matcher,Next> &’ I am not familiar with the fusion or xpressive libraries, but after picking through the error messages and review of diff of changes since 1.54 (the version we are moving from), this looks like a template specialization problem. The problem is rooted in a regex that uses xpressive in the escape_dot_string function in the graphviz library. In 1.58 the function at the line identified in the error snip above is defined as follows: template <typename Sequence> BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED cons( Sequence const& seq, typename boost::enable_if< mpl::and_< traits::is_sequence<Sequence>, mpl::not_<is_convertible<Sequence, Car> > > // use copy to car instead >::type* /*dummy*/ = 0 ) : car(*fusion::begin(seq)), cdr(fusion::next(fusion::begin(seq)), mpl::true_()) {} When we replace this with the following implementation from 1.54 the build works and it appears the desired functionality is working (though more testing is required). template <typename Sequence> BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED cons( Sequence const& seq, typename boost::disable_if< mpl::or_< is_convertible<Sequence, cons>, // use copy ctor instead is_convertible<Sequence, Car> // use copy to car instead > >::type* /*dummy*/ = 0 ) : car(*fusion::begin(seq)), cdr(fusion::next(fusion::begin(seq)), mpl::true_()) {} Any thoughts? The new code in 1.58 builds and runs fine with no mods on OS X. We have not tried Linux yet.

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[msm] is that correct behavior?
by Sam Fisher 29 Jun '15

29 Jun '15

Hi Christophe, For an fsm with orthogonal regions if any region rejects an event (guard returns false), the library blocks all anonymous transitions. for example, an fsm has two regions. Region 0 returns HANDLED_TRUE, region 1 returns HANDLED_GUARD_REJECT for the same event. region_processing_helper combines it into a single "HANDLED_TRUE | HANDLED_GUARD_REJECT" value. However function process_event_internal<> (state_machine.hpp) creates handle_eventless_transitions_helper that takes (handled == HANDLED_TRUE) as a condition for allowing transitions. should it be (handled & HANDLED_TRUE)? as a result, fsm is stuck in event that has an anonymous transition to another event. PS. I've seen the same condition (handled == HANDLED_TRUE) in do_post_handle_deferred function, but I do not use deferred events so I did not check that part.

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[PBGL] Creating graph on multiple processes
by Alexander Frolov 29 Jun '15

29 Jun '15

Hi! I am trying to create undirected weighted graph on two mpi-processes. I use add_edge function to add edges (master (pid=0) process is responsible for this). For small graphs everything is ok. But when I create larger graphs (for instance, number of vertices is 2^20 and number of edges is 2^28) the program hangs supposedly in add_edge. For mpirun -np 1 there is no such problem. What can cause this issue? Thanks for any help! Best, Alex

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Boost.DLL formal review
by Vladimir Prus 29 Jun '15

29 Jun '15

The formal review of Boost.DLL library by Antony Polukhin starts today. Boost.DLL is a C++98 library for comfortable work with DLL and DSO. Library provides a portable across platforms way to: - load libraries at runtime - import and export any native functions and variables - make alias names for C++ mangled functions and symbols - query libraries/objects and executables for sections and exported symbols - self loading and self querying - getting program and module location by exported symbol The documentation can be found at: http://apolukhin.github.io/Boost.DLL/index.html and the source can be obtained at: https://github.com/apolukhin/Boost.DLL Please post your reviews on the mailing list and if possible, answer the following questions: - Should the library be accepted? - How useful is it? - What's your evaluation of - Design - Implementation - Documentations - Tests - How much effort did you put into your evaluation? - Did you attempt to use the library? On what systems and compilers? This formal review has a couple of adjustments in place: - It will run for two calendar weeks, not for 10 days, as a number of people said 10 days is too little. That said, please try to submit a review during first week, so that necessary discussion can happen conveniently. - The documentation site has Google Analytics enabled, which will allow us to see which pages and navigation paths are most useful for reviewers. No personally identifiable information will be collected. I will post the data after the review is over. Thanks, Volodya

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[Boost][DateTime] Non conforming iterators?
by dariomt＠gmail.com 29 Jun '15

29 Jun '15

Hi, The documentation for Boost.Date_Time iterators says that "Date iterators are a model of Bidirectional Iterator". However, I am not able to use them in some STL algorithms because of the lack of a required nested type. The following simplified example does not compile: #include <boost/date_time/gregorian/gregorian.hpp> #include <algorithm> void main() { using namespace boost::gregorian; date v[5]; std::copy_n( month_iterator( date(2015,06,25) ), 5, v ); } On VS2013 fails with error 'difference_type' : is not a member of 'boost::date_time::date_itr<boost::date_time::month_functor<boost::gregorian::greg_durations_config::date_type>,boost::gregorian::date>' Compilation on gcc and clang fails with a similar error complaining about the lack of 'difference_type'. Isn't a nested difference_type a requirement of BidirectionalIterator? Am I using these date iterators incorrectly? Regards

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[multi_index] are indices in a random access index stable on addition, can we have an "index_of" method?
by Nick Stokes 27 Jun '15

27 Jun '15

I have a stream of pairs of elements of type T, and want to insert individual T's uniquely into a container and convert the pairs to a pair of indices into this container. Boost.MultiIndex seems to be cut out exactly for this job, but I not sure about how to obtain the indices or stability of them on addition: Take, namespace bmi = boost::multi_index; typedef bmi::multi_index_container< T, bmi::indexed_by < bmi::hashed_unique< bmi::identity<T> > , bmi::random_access<> >> MIC; MIC elements; std::vector<std::pair<int,int>> pairs; for( const std::pair<T,T>& pt : stream ) { auto t1 = elements.insert(pt.first).first; // not all insertions are successful of course auto t2 = elements.insert(pt.second).first; pairs.insert( index_of(t1), index_of(t2) ); } // where index_of() is auto index_of = [&]( MIC::const_iterator i ) { return elements.project<1>(i) - elements.get<1>().begin(); } So my questions are (1) Is the implementation of index_of() correct? (or better, is there something like this already for random access indices) (2) Is the way they are used in above loop stable, where elements are inserted after an index is obtained? Thanks Nick

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Re: [Boost-users] [Test] How to Access Private Data from a Test
by Jürgen Hunold 26 Jun '15

26 Jun '15

Hi Steven, On Donnerstag, 25. Juni 2015 21:24:51 Steven Clark wrote: > This remark really puzzles me. > Do you feel that white-box testing should > never be done? Or should never be needed? Both, in fact. See Gavin's mail for the rationale. He explained it better than I would have :-) In fact, I've got a long way with black-box testing only in the past five years, so I have strong evidence that white-box testing is unnecessary. But this is on a fresh, test-driven developed code base. Designed to be black-box testable. > > On Jun 25, 2015, at 4:52 PM, Jürgen Hunold <jhunold(a)gmx.eu> wrote: > > In my opinion, a test should never access private data. Note the "In my opinion" :-) > > But there are times > > and legacy code where I had no other choice, too. And then I wrote the disclaimer that sometimes you can't do everything with black-box testing. I tried hard to get a test harness up for some legacy code in the years before and got stuck in multiple nested class hell, some d- Pointer magick and class hierarchies hard to instantiate. That is the reason why I was able to actually grep for the friend declarations needed in those cases. Not nice in my opinion, but "an ugly test is better than no test" (see http://www.artima.com/weblogs/viewpost.jsp?thread=203994 for more on a pragmatic view on unit tests). Which leads to the question if the OP was able to solve the issue or stopped reading after the first paragraph. Yours, Jürgen -- * Dipl.-Math. Jürgen Hunold ! * voice: ++49 4257 300 ! Fährstraße 1 * fax : ++49 4257 300 ! 31609 Balge/Sebbenhausen * jhunold(a)gmx.eu ! Germany

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[Test] How to Access Private Data from a Test
by Merrill Cornish 26 Jun '15

26 Jun '15

In the Bad-Old-Days when I had to roll my own, I would define my tests as methods of a special test class. If those tests needed to access private data in the classes under test, I would declare special test class as a friend of the class under test--one extra statement and everything worked. How do I do that using Boost test (1.58.0) with the AUTO_TEST family of macros? In the labyrinth of macro expansions, I found a struct name with the argument name from BOOST_AUTO_TEST_CASE(), but a friend of that name doesn't work. The ideal case would be to declare the string name in BOOST_AUTO_TEST_SUITE() as a friend so one friend declaration does it all. Alternately, having to declare a separate friend for each BOOST_AUTO_TEST_CASE() would be tedious (especially for large classes), but it would work. At the moment, I'm using the ole private=public trick: #define private public #include "header_under_test" #undef private However, I've already discovered one system header, <sstream>, that won't work with that kludge. There may be others. Is there another workaround for Boost Tests? I can't be the only one who has to access private data in tests. Merrill Cornish

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Interprocess - 3rd process cannot read/write the shared memory
by Lloyd 25 Jun '15

25 Jun '15

Hi, I am working on Windows 7, boost 1.57. I am using interprocess shared memory. I have two processes A and B. A creates the shared memory with read/write permission, then B opens it and writes to it. In this case it works fine. As the next step process A terminates and starts again and opens the same shared memory. But in this case, it seems that A and B are reading/writing to different memory! Is this a defined behavior? If I make B to reopen the memory, it works! Thanks, Lloyd

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[datetime] little problem with periods
by Georg.Kellerer＠lfu.bayern.de 24 Jun '15

24 Jun '15

Hello, i am using Boost V1.5.8 under vs 2010 with a german windows 7 64 bit. When I tried to calculate a time period I always ran into the same problem. The period is calculated one day too short. I wrote a little program to illustrate my problem. It's important that you change the value of the variable test to the current date. Is this a bug or do I use the library in an incorrect way? Thanks a lot, Georg #include "boost/date_time.hpp" #include <iostream> using namespace std; using namespace boost::gregorian; int main() { date today = day_clock::local_day(); date test(2015,6,23); // Change value to current date date first(1965,10,26); date_period period(first, today); if (!period.contains(test)) cout << "shouldn't be our testdate in the period? " << endl; }

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Printing local edge list in PBGL
by Alexander Frolov 23 Jun '15

23 Jun '15

Hi, I have a simple program using PBGL (boost 1.58) which creates an undirected graph and prints local edge list for the specified process. However, only for zero process the list (edges(g)) contains edge descriptors, while for non-zero processes the list is empty, which is strange, is it not? The program text is following: using namespace boost; using boost::graph::distributed::mpi_process_group; using boost::graph::parallel::process_group; std::size_t nVertices = 16; int main(int argc, char **argv) { boost::mpi::environment env(argc, argv); mpi_process_group pg; typedef adjacency_list<listS, distributedS<mpi_process_group, vecS>, undirectedS, // Vertex properties no_property, // Edge properties property<edge_weight_t, int> > Graph; Graph g(nVertices); if (process_id(pg) == 0) { std::cout << "MST Boost running..." << std::endl; std::cout << "\tnumber of mpi processes is " << num_processes(pg) << std::endl; std::cout << "\tnumber of vertices is " << nVertices << std::endl; std::cout << "\tnumber of edges is " << /*nEdges*/ nVertices << std::endl; std::cout << "Constructing graph..."; for (int i = 0; i < nVertices; i++) { uint64_t s = (i < nVertices/2) ? 0 : nVertices/2; //uint64_t s = 0; uint64_t d = i; uint64_t w = rand(); add_edge(vertex(s, g), vertex(d, g), w, g); } std::cout << "...completed" << std::endl; } synchronize(pg); typedef property_map<Graph, edge_weight_t>::type WeightMap; WeightMap weight_map = get(edge_weight, g); if (process_id(pg) == atoi(argv[1])){ std::cout << "printing vertices:\n"; Graph::vertex_iterator v, v_end; for (boost::tie(v,v_end) = vertices(g); v != v_end; v++) { std::cout << process_id(pg) << ": (" << local(*v) << "@" << owner(*v) << ")\n"; } std::cout << "end of vertex list.\n"; std::cout << "printing edges:\n"; for (typename Graph::edge_iterator ei = edges(g).first; ei != edges(g).second; ei++) { std::cout << process_id(pg) << ": (" << local(source(*ei, g)) << "@" << owner(source(*ei,g)) << "," << local(target(*ei, g)) << "@" << owner(target(*ei,g)) << "," << get(weight_map, *ei) << ")\n"; } std::cout << "end of edge list.\n"; } return 0; } The output for the process 0: mpirun -np 2 ./simple_test 0 MST Boost running... number of mpi processes is 2 number of vertices is 16 number of edges is 16 Constructing graph......completed printing vertices: 0: (0@0) 0: (1@0) 0: (2@0) 0: (3@0) 0: (4@0) 0: (5@0) 0: (6@0) 0: (7@0) end of vertex list. printing edges: 0: (0@0,0@0,1804289383) 0: (0@0,1@0,846930886) 0: (0@0,2@0,1681692777) 0: (0@0,3@0,1714636915) 0: (0@0,4@0,1957747793) 0: (0@0,5@0,424238335) 0: (0@0,6@0,719885386) 0: (0@0,7@0,1649760492) 0: (0@0,0@1,596516649) 0: (0@0,1@1,1189641421) 0: (0@0,2@1,1025202362) 0: (0@0,3@1,1350490027) 0: (0@0,4@1,783368690) 0: (0@0,5@1,1102520059) 0: (0@0,6@1,2044897763) 0: (0@0,7@1,1967513926) end of edge list. The output for the process 1: mpirun -np 2 ./simple_test 1 MST Boost running... number of mpi processes is 2 number of vertices is 16 number of edges is 16 Constructing graph......completed printing vertices: 1: (0@1) 1: (1@1) 1: (2@1) 1: (3@1) 1: (4@1) 1: (5@1) 1: (6@1) 1: (7@1) end of vertex list. printing edges: end of edge list. Is it ok? or there is a bug in the code? Appreciate any help. Thanks a lot. Best, Alex

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Re: [Boost-users] [datetime] little problem with periods
by Georg.Kellerer＠lfu.bayern.de 23 Jun '15

23 Jun '15

Hi Boris, thanks for your help. In fact I didn't know that. Georg -----Ursprüngliche Nachricht----- Von: Boost-users [mailto:boost-users-bounces@lists.boost.org] Im Auftrag von Boris Schäling Gesendet: Dienstag, 23. Juni 2015 14:46 An: boost-users(a)lists.boost.org Betreff: Re: [Boost-users] [datetime] little problem with periods On Tue, 23 Jun 2015 13:42:03 +0200, <Georg.Kellerer(a)lfu.bayern.de> wrote: > Hello, > > i am using Boost V1.5.8 under vs 2010 with a german windows 7 64 bit. > When I tried to calculate a time period I always ran into the same > problem. The period is calculated one day too short. I wrote a little > program to illustrate my problem. It's important that you change the > value of the variable test to the current date. Is this a bug or do I > use the library in an incorrect way? The end of the period is not considered part of the period (see <http://theboostcpplibraries.com/boost.datetime-calendar#ex.datetime_08> or <http://dieboostcppbibliotheken.de/boost.datetime-kalenderdaten#ex.datetime_…> if you prefer German). HTH, Boris > [...] _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users

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Re: [Boost-users] [datetime] little problem with periods
by Georg.Kellerer＠lfu.bayern.de 23 Jun '15

23 Jun '15

Hello Michael, > Is date period a boost function or one of your own? No, its part of boost. Georg

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[Serialization] Boost segfaults in archive/basic_xml_iarchive.hpp
by Mccall, Kurt E. (JSC-EG411) 22 Jun '15

22 Jun '15

If someone could help me diagnose this segmentation fault, I'd appreciate it greatly. It has stumped me for a couple of days. I'm deserializing a non-polymorphic derived class, and Boost crashes when it attempts to process the base class: Here is the pseudocode: struct Base { int id_; std::string long_name_; template<Archive> void serialize(Archive & ar, const unsigned int file_version) { ar & BOOST_SERIALIZATION_NVP(id_); ar & BOOST_SERIALIZATION_NVP(long_name_); // SEGFAULT OCCURS HERE } } struct Derived : public Base { template<Archive> void serialize(Archive & ar, const unsigned int file_version) { ar & BOOST_SERIALIZATION_BASE_OBJECT_NVP(Base); … } } I tried the methods described at http://stackoverflow.com/questions/3396330/where-to-put-boost-class-export-… for exporting the derived class using BOOST_CLASS_EXPORT, but none of them affected the segfault. I guess that it isn't really necessary to export non-polymorphic derived classes. Anyway, the code crashes in archive/basic_xml_iarchive.hpp in this code at line 92: // Anything not an attribute - see below - should be a name value // pair and be processed here typedef detail::common_iarchive<Archive> detail_common_iarchive; template<class T> void load_override( #ifndef BOOST_NO_FUNCTION_TEMPLATE_ORDERING const #endif boost::serialization::nvp< T > & t, int ){ this->This()->load_start(t.name()); this->detail_common_iarchive::load_override(t.value(), 0); // SEGFAULT OCCURS HERE this->This()->load_end(t.name()); } In GDB, "this" has a valid address ( 0x7fffffffdb30) as does "t" (0x7ffffff487b0). In GDB, executing t.name() yielded the correct name "long_name_", but when executing t.value(), the debugger complained about an invalid address: RuntimeError: Cannot access memory at address 0xffffffffffffffe8 That error message comes from GDB's Python utility for pretty-printing strings (the variable being deserialized is a std::string), which is invoked when I print t.value(), but regardless something is wrong in t.value(). Does any of this suggest what I might be doing wrong? Thanks for any help.

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[Serialization] Non-default constructor and template class
by Mccall, Kurt E. (JSC-EG411) 22 Jun '15

22 Jun '15

I am attempting to serialize a template class without a default constructor, so I am overriding boost::serialization::save_construct_data(). I'm not sure of the correct syntax to declare that function. The line marked below fails to compile with a "too many template-parameter-lists" error. // Forward declaration of my class template<class Key, class Value, class Hasher> class HashMap; namespace boost { namespace serialization { template<class Archive> template<class Key, class Value, class Hasher> void save_construct_data(Archive &ar, const HashMap< Key, Value, Hasher > *t, const unsigned int file_version); // error here }} Thanks for any help, Kurt

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