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catch real time signals
by Halim DJERROUD 14 Aug '14

14 Aug '14

hi, I try to intercept real-time signals (SIGMIN + 1, SIGMIN +2 ...) it works when I send a signal (kill -35 PID) it works well only if i send one signal, when i send another signal or same signal second time (kill -35 PID) the pogram does not intercept the signal I feel that run () stops the service after having received the first signal Thank you for your help, Here are the code: #define SIG1 (SIGRTMIN + 1) #define SIG1 (SIGRTMIN + 2) ... class Agent { ... signal_handler(const boost::system::error_code& error, int signal_number) {...} ... } ... boost::asio::signal_set signals(io_serv); signals.add(SIG1) signals.add(SIG2) ... signals.async_wait( boost::bind(&Agent::signal_handler, this, boost::asio::placeholders::error, boost::asio::placeholders::signal_number)); io_serv.run(); for (;;) { std::this_thread::yield(); } (I use Linux and g++) -- Merci d'avance Halim DJERROUD

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[boost::interprocess] named_recursive_mutex lock owner identification
by Frank Bergemann 14 Aug '14

14 Aug '14

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Boost Library Writers Workshop at CPP Con 2014
by Robert Ramey 14 Aug '14

14 Aug '14

Have you been lurking out there in cyberspace all these years? Slaving away on your fantastic new library for boost? Stuck, discouraged, concerned about getting ripped apart on the mailing list? Well, this is for you !!!! The Boost Library Writers Workshop http://rrsd.com/blincubator.com/open-content/ . Share your library and get it critiqued by you peer group - other unsung authors battling the same daemons. Best of all you can attend this workshop without being registered at the conference - to attend this workshop all you have to do is ... attend!. That's right, it's absolutely free. That's right free. And not free like in free software. Really free like "free beer". (note: there is no free beer). So if you're in the area and you want to get your library off your chest because it's weighing you down, keeping you awake, ruining your love life attend this workshop. Spaces are limited so signup now at the above web page. Robert Ramey -- View this message in context: http://boost.2283326.n4.nabble.com/Boost-Library-Writers-Workshop-at-CPP-Co… Sent from the Boost - Users mailing list archive at Nabble.com.

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boost::serialization: 'serialize' is not a member of 'Eigen::internal::workaround_msvc_stl_support<T>'
by LynnC 13 Aug '14

13 Aug '14

Boost 1.50 MSVS 2010 My problem occurs when I attempt to serialize pcl::PointCloud<pcl::PointXYZ> g...specifically g.points which is std::vector<Point, Eigen::aligned_allocator<Point> > pcl::PointCloud<Point>::points. I have the following code: #ifndef SERIALIZATIONSUPPORT_H #define SERIALIZATIONSUPPORT_H #include <pcl/point_cloud.h> #include <pcl/io/pcd_io.h> #include <pcl/point_types.h> // needed for pcl::PointXYZ Point #include <boost/serialization/base_object.hpp> #include <boost/serialization/utility.hpp> #include <boost/serialization/list.hpp> #include <boost/serialization/assume_abstract.hpp> #include <boost/serialization/vector.hpp> typedef pcl::PointXYZ Point; namespace boost { namespace serialization { template<class Archive> void serialize(Archive & ar, pcl::PointCloud<Point>& g, const unsigned int version) { ar & g.points; } template<class Archive> void serialize(Archive & ar, Point& g, const unsigned int version) { ar & g.getVector3fMap().data()[0]; ar & g.getVector3fMap().data()[1]; ar & g.getVector3fMap().data()[2]; } } // namespace serialization } // namespace boost #endif /* SERIALIZATIONSUPPORT_H */ Error received: error C2039: 'serialize' : is not a member of 'Eigen::internal::workaround_msvc_stl_support<T>' Special notes...no problems with my code when compiling on Ubuntu 12.04 LTS using Boost 1.48. Only a problem when compiling on Windows. Any idea as to why I would be receiving this? I already have a method for serializing Point. Shouldn't that be enough? -- View this message in context: http://boost.2283326.n4.nabble.com/boost-serialization-serialize-is-not-a-m… Sent from the Boost - Users mailing list archive at Nabble.com.

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composite_key with array member
by Uthpal Urubail 13 Aug '14

13 Aug '14

I am looking for a container where I have to use 5-10 keys to get the value. I am trying to write something like below.. Can some one help to solve this? struct entry { int a[10]; int id; }; using boost::multi_index_container; using namespace boost::multi_index; typedef multi_index_container< entry, indexed_by< ordered_non_unique< composite_key< entry, member<entry,unsigned int,&entry::a> ???? > >, ordered_unique< member<entry,unsigned int,&entry::id> > > > book; Regards, UJ

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[BGL] Question about using remove_edge() in boost graph library
by Yi-Ping Huang 12 Aug '14

12 Aug '14

Dear boost-users: I just start learning boost graph library and have a basic problem on using the remove_edge function in boost graph library. I would like to remove an edge in a multigraph. For a graph with two edges connect vertice 0 and 1, I would like to remove one of them, but kept the other. According to the user guide, remove_edge(u ,v , g) removes all occurrences of (u ,v). So I should use remove_edge(e ,g) instead. Here, e is a valid edge descriptor. For a single graph, g, I am able to perform both remove_edge(u ,v , g) and remove_edge(e ,g) operation. However, when I want to generalize the implementation to fit my need by putting graphs in a vector container, I got segmentation fault for remove_edge(e ,graph_list[0]). (The compiler show no warning message.) On the other hand, remove_edge(u,v,g) works perfectly. I am not sure what's the difference between those two syntax causes this problem. I really want to make remove_edge(e,g) and vector container work at the same time. So any suggestion that can help my bypass this difficulty is appreciated. Thanks a lot!! Yi-Ping

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Allocation/deallocations during boost serialization (tracking help?)
by miles_c＠verizon.net 12 Aug '14

12 Aug '14

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asio::ip::tcp iostream wrong byte count read for last packet
by Steve Coleman 12 Aug '14

12 Aug '14

I just started out with Boost and was writing a little binary file transfer app and ran into a little problem, so I would appreciate if someone could kindly point out what I am doing wrong here. My problem is in getting the correct byte count read in the final packet received. My last frame always returns the size of the buffer, not the number of bytes read into the buffer. Isn't iostream::gcount(() meant for this? If not, what is the correct 'Boost' way of doing this? int spool_binary_data() { boost::asio::ip::tcp::endpoint dataServerEndpoint(boost::asio::ip::tcp::v4(), PMMS_TRANSFER_PORT_NUMBER); boost::asio::ip::tcp::acceptor acceptor(dataServer, dataServerEndpoint); boost::asio::ip::tcp::iostream dataServerStream; acceptor.accept(*dataServerStream.rdbuf()); char buffer[2048]; std::streamsize nbytes = sizeof(buffer); FILE * pFile = fopen ("binary.out","w"); // count = getavailable(this->native_socket) ?? // stream->rdbuf()->available() ?? while ( dataServerStream.read((char*)&buffer, nbytes) ) { int bytes_read = dataServerStream.gcount(); // always 2048 std::cout << "bytes read " << bytes_read << std::endl; fwrite(buffer,1,bytes_read,pFile); } dataServerStream.close(); fclose(pFile); }

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Basic question about using remove_edge() in boost graph library
by Yi-Ping Huang 11 Aug '14

11 Aug '14

Dear boost-users: I just start learning boost graph library and have a basic problem on using the remove_edge function in boost graph library. I would like to remove an edge in a multigraph. For a graph with two edges connect vertice 0 and 1, I would like to remove one of them, but kept the other. According to the user guide, remove_edge(u ,v , g) removes all occurrences of (u ,v). So I should use remove_edge(e ,g) instead. Here, e is a valid edge descriptor. For a single graph, g, I am able to perform both remove_edge(u ,v , g) and remove_edge(e ,g) operation. However, when I want to generalize the implementation to fit my need by putting graphs in a vector container, I got segmentation fault for remove_edge(e ,graph_list[0]). I really want to make remove_edge(e,g) and vector container work at the same time. So any suggestion that can help my bypass this difficulty is appreciated. Thanks a lot!! Yi-Ping *************************Here is the complete code************************* #include <iostream> #include <utility> #include <algorithm> #include <vector> #include "boost/graph/graph_traits.hpp" #include "boost/graph/adjacency_list.hpp" using namespace boost; typedef adjacency_list<vecS, vecS, undirectedS> UndirectedGraph; typedef boost::graph_traits<UndirectedGraph>::edge_iterator edge_iterator; int graph_show(UndirectedGraph &g); int main(int argc, char *argv[]) { UndirectedGraph g; typedef boost::graph_traits<UndirectedGraph>::edge_descriptor edge_descriptor; edge_descriptor ed; std::vector<edge_descriptor> edge_list; std::vector<std::vector<edge_descriptor> > graph_edge_list; std::vector<UndirectedGraph> graph_list; int nb=0; int Nl=4; bool inserted; while(nb<Nl) { tie(ed,inserted)=add_edge(nb,nb+1,g); edge_list.push_back(ed); tie(ed,inserted)=add_edge(nb,nb+1,g); edge_list.push_back(ed); graph_edge_list.push_back(edge_list); nb=nb+1; graph_list.push_back(g); } std::cout<<"size of the graph vector is: "<<graph_list.size()<<std::endl; remove_edge(graph_edge_list[0][0],graph_list[0]);//This is where the problem shows. //I got Segmentation fault (core dumped) //remove_edge(0,1,graph_list[0]); /*Remove edges by assigning vertices works fine, but that is not what I need.*/ for (int ig = 0; ig < Nl; ++ig) { std::cout<<"graph#"<<ig<<std::endl; std::cout<<"Size of edge_list is: "<<graph_edge_list[ig].size()<<std::endl; graph_show(graph_list[ig]); } std::cout<<"Success"<<std::endl; return 0; } int graph_show(UndirectedGraph &g) { std::cout<<"Number of edges is : "<<boost::num_edges(g)<<std::endl; std::cout<<"Number of vertices is : "<<boost::num_vertices(g)<<std::endl; std::pair<edge_iterator,edge_iterator> ei=edges(g); for (edge_iterator edge_iter = ei.first; edge_iter!=ei.second; ++edge_iter) { std::cout<<"("<< boost::source(*edge_iter,g)<<","<<boost::target(*edge_iter,g)<<")"<<std::endl; } typedef boost::graph_traits<UndirectedGraph>::vertex_iterator iter_v; std::cout<<"vertices(g)={ "; for (std::pair<iter_v,iter_v> p = vertices(g); p.first != p.second; ++p.first) { std::cout<< *p.first; std::cout<<" "; } std::cout<<"}"<<std::endl; return 0; }

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[String algorithms] User defined finders and predicates
by Aaron Levy 11 Aug '14

11 Aug '14

Are there good examples of writing user defined finders and predicates for functions such as find_token? Aaron

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Boost 1.56.0 has been released
by Marshall Clow 11 Aug '14

11 Aug '14

Release 1.56.0 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 one new library and numerous enhancements and bug fixes for existing libraries. === Modularization === Boost version control has migrated to a system using git submodules. This shouldn't make too much of a difference to users, although the directory structure is now a bit different. Parts of some libraries have been moved into different modules, and several new modules have been extracted from existing code. All header paths should remain the same. The new modules are: • Assert: Customizable assert macros. Maintained by Peter Dimov. • Core: Core utilities used by other libraries, with minimal dependencies. Maintained by Peter Dimov, Glen Fernandes and Andrey Semashev. • Lexical_Cast: General literal text conversions, such as an int represented a string, or vice-versa, from Kevlin Henney. • Throw_Exception: A common infrastructure for throwing exceptions from Boost libraries, from Emil Dotchevski. • Winapi: Windows API declarations without <windows.h>, for internal Boost use. === New Libraries === • Align: Memory alignment functions, allocators, and adaptors, from Glen Fernandes. • Type_Index: Runtime/Compile time copyable type info, from Antony Polukhin. For details, including download links, see http://www.boost.org/users/news/version_1.56.0 You can also download directly from SourceForge: http://sourceforge.net/projects/boost/files/boost/1.56.0/ 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 Vladimir Prus Rene Rivera Marshall Clow Eric Niebler Daniel James Beman Dawes

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[asio] multiple simultaneous async_read calls
by bbxiong 11 Aug '14

11 Aug '14

Hello, all, If i write some code like this: boost::asio::async_read(socket_, bosot::asio::buffer(buffer1_.data(), len1, handler1); boost::asio::async_read(socket_, boost::asio::buffer(buffer2_.data(), len2, handler2); Will asio guarantee len1 bytes received by the first async_read, then schedule async_read2? or the result is undefined(like several bytes filled into buffer1, then next several bytes into buffer, then next several bytes into buffer1)? if the result is undefined, why asio don't add a check here? Thanks all in advance!

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[Boost.Thread] Compile error: boost::promise<T>::set_value(const T&) doesn't exist
by Rob Desbois 10 Aug '14

10 Aug '14

Hi all, I'm having problems compiling with Boost.Thread's futures I can't seem to pass anything but a primitive type into make_ready_future. I've had problems with other parts of Thread (packaged_task, promise, unique/shared_future) that have produced horrendously unhelpful compile errors. Here is a minimal testcase: #include <boost/thread/future.hpp> struct foo { foo(int i_): i(i_) {} int i; }; int main() { // A const future ref isn't much use, but I needed to prove // the problem wasn't me trying to copy a unique_future const boost::unique_future<foo>& fut = boost::make_ready_future( foo(42) ); } With `BOOST_THREAD_USES_MOVE` defined before including the Boost.Future header I get the following error with gcc 4.8.2 and Boost 1.55 (full output at http://pastebin.com/0sePWBWr) ../../deps/boost/include/boost/thread/future.hpp:3634:5: error: no matching function for call to ‘boost::promise<foo>::set_value(const foo&)’ p.set_value(boost::forward<future_value_type>(value)); ^ There seems to be no overload of promise::set_value() that takes a const lvalue reference. Looking at `promise` and `future_traits` in `future.hpp` it seems that the const lvalue ref overload will only exist when `BOOST_NO_CXX11_RVALUE_REFERENCES` is undefined. That makes no sense to me however...surely the const lvalue ref overload is needed precisely when there are no rvalue references? (Note this happens even if I pass a mutable lvalue ref to `make_ready_future()`). If I don't define `BOOST_THREAD_USES_MOVE` it fails compilation with the following error (full output at http://pastebin.com/jBwiJLeC) ../../deps/boost/include/boost/thread/detail/move.hpp:183:54: error: no matching function for call to boost::unique_future<foo>::unique_future(boost::unique_future<foo>)’ #define BOOST_THREAD_MAKE_RV_REF(RVALUE) RVALUE.move() ^ Have I missed something? I'm unable to switch to C++11 mode unfortunately, but this seems such a big problem I can only assume I've done something wrong. I still get similar compile errors trying with Clang 3.4, and also with Boost 1.54 (g++ or Clang). -- Rob Desbois http://theotherbranch.wordpress.com/

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[Boost.Range] Filtering elements at even position
by Arindam Mukherjee 10 Aug '14

10 Aug '14

I am trying to create a range consisting of elements in a container at only even indexes. Is there a way to write something like: vec | boost::adaptors::indexed(0) | some_adaptor_to_choose_even_indexes I tried with boost::adaptors::filtered, but the index information is only present in iterators of the generated range, not in its value_type so it is not available in chained adaptors. - Arindam

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Boost 1.56.0 compilation error in iterator_range
by gast128 10 Aug '14

10 Aug '14

I get a compilation error with vc10, iterator_range and a (const) unordered_map (the beta candidate 2 was still ok I think): #include "stdafx.h" #include <boost/range/iterator_range.hpp> #include <boost/unordered_map.hpp> int _tmain(int /*argc*/, _TCHAR* /*argv*/[]) { typedef boost::unordered_map<int, int> Container; typedef Container::const_iterator ContainerIterator; typedef boost::iterator_range<ContainerIterator> ContainerIteratorRange; const Container cnt; ContainerIteratorRange rng(cnt.cbegin(), cnt.cend()); return 0; } This gives C2248: 'boost::unordered::iterator_detail::c_iterator<Node,ConstNodePointer>::iterator' cannot access private typedef declared in class etc. (note had to cut due to 'you have lines longer than 80 characters. Fix that.' in Gmane)

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[boost] [1.55] numerous warnings with gcc 4.8.3 on Linux
by Marius Lazer 08 Aug '14

08 Aug '14

All the warnings are similar to this (warning: typedef âboost_concept_check185â locally defined but not used [-Wunused-local-typedefs]): ./boost/range/algorithm/equal.hpp: In function âbool boost::range::equal(const SinglePassRange1&, const SinglePassRange2&, BinaryPredicate)â: ./boost/concept/detail/general.hpp:71:20: warning: typedef âboost_concept_check185â locally defined but not used [-Wunused-local-typedefs] BOOST_PP_CAT(boost_concept_check,__LINE__) ^ ./boost/preprocessor/cat.hpp:29:34: note: in definition of macro âBOOST_PP_CAT_Iâ # define BOOST_PP_CAT_I(a, b) a ## b ^ ./boost/concept/detail/general.hpp:71:7: note: in expansion of macro âBOOST_PP_CATâ BOOST_PP_CAT(boost_concept_check,__LINE__) ^ ./boost/concept/assert.hpp:44:5: note: in expansion of macro âBOOST_CONCEPT_ASSERT_FNâ BOOST_CONCEPT_ASSERT_FN(void(*)ModelInParens) ^ ./boost/range/concepts.hpp:92:45: note: in expansion of macro âBOOST_CONCEPT_ASSERTâ #define BOOST_RANGE_CONCEPT_ASSERT( x ) BOOST_CONCEPT_ASSERT( x ) ^ ./boost/range/algorithm/equal.hpp:185:13: note: in expansion of macro âBOOST_RANGE_CONCEPT_ASSERTâ BOOST_RANGE_CONCEPT_ASSERT(( SinglePassRangeConcept<const SinglePassRange1> )); ^ ./boost/concept/detail/general.hpp:71:20: warning: typedef âboost_concept_check186â locally defined but not used [-Wunused-local-typedefs] BOOST_PP_CAT(boost_concept_check,__LINE__) ^ ./boost/preprocessor/cat.hpp:29:34: note: in definition of macro âBOOST_PP_CAT_Iâ # define BOOST_PP_CAT_I(a, b) a ## b ./boost/concept/detail/general.hpp:71:7: note: in expansion of macro âBOOST_PP_CATâ BOOST_PP_CAT(boost_concept_check,__LINE__) ^ ./boost/concept/assert.hpp:44:5: note: in expansion of macro âBOOST_CONCEPT_ASSERT_FNâ BOOST_CONCEPT_ASSERT_FN(void(*)ModelInParens) ^ ./boost/range/concepts.hpp:92:45: note: in expansion of macro âBOOST_CONCEPT_ASSERTâ #define BOOST_RANGE_CONCEPT_ASSERT( x ) BOOST_CONCEPT_ASSERT( x ) ^ ./boost/range/algorithm/equal.hpp:186:13: note: in expansion of macro âBOOST_RANGE_CONCEPT_ASSERTâ BOOST_RANGE_CONCEPT_ASSERT(( SinglePassRangeConcept<const SinglePassRange2> )); Thanks, Marius Marius S. Lazer ICAP North America Inc. Harborside Financial Center 1100 Plaza 5 Jersey City, NJ 07311-4996 Office: 212-815-7470 Email: Marius.Lazer(a)us.icap.com ********************************************************************** This communication and all or some of the information contained therein may be confidential and is subject to our Terms and Conditions. If you have received this communication in error, please destroy all electronic and paper copies and notify the sender immediately. Unless specifically indicated, this communication is not a confirmation, an offer to sell or solicitation of any offer to buy any financial product, or an official statement of ICAP or its affiliates. Non-Transactable Pricing Terms and Conditions apply to any non-transactable pricing provided. All terms and conditions referenced herein available at www.icapterms.com. Please notify us by reply message if this link does not work. ********************************************************************** ICAP's 21st global annual Charity Day – took place Tuesday 3 December 2013. Together we raised £9.5 million (US$15.5 million), totalling £110 million since 1993. www.icapcharityday.com --------------------------------------------------------------------------------------- This email has been scanned for email related threats and delivered safely by Mimecast. For more information please visit http://www.mimecast.com ---------------------------------------------------------------------------------------

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BOOST_STRONG_TYPEDEF
by Jono Poff 08 Aug '14

08 Aug '14

Hi, compiling this program with g++ 4.7.1 ... #include <boost/serialization/strong_typedef.hpp> BOOST_STRONG_TYPEDEF(uint32_t, LINKID_T) int main() { LINKID_T lid = 0xffddee33; return 0; } I get error: conversion from 'unsigned int' to non-scalar type 'LINKID_T' requested Looking at the header, the strong typedef struct defines assignment from uint32_t to LINKID_T ... D & operator=(const T & rhs) { t = rhs; return *this;} ... so what gives? Cheers, Jono -- ------------------------------ This email, including any attachments, is only for the intended recipient. It is subject to copyright, is confidential and may be the subject of legal or other privilege, none of which is waived or lost by reason of this transmission. If you are not an intended recipient, you may not use, disseminate, distribute or reproduce such email, any attachments, or any part thereof. If you have received a message in error, please notify the sender immediately and erase all copies of the message and any attachments. Unfortunately, we cannot warrant that the email has not been altered or corrupted during transmission nor can we guarantee that any email or any attachments are free from computer viruses or other conditions which may damage or interfere with recipient data, hardware or software. The recipient relies upon its own procedures and assumes all risk of use and of opening any attachments. ------------------------------

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BOOST_STRONG_TYPEDEF ...ps
by Jono Poff 08 Aug '14

08 Aug '14

Sorry, forgot to say Boost 1.55.0 Jono -- ------------------------------ This email, including any attachments, is only for the intended recipient. It is subject to copyright, is confidential and may be the subject of legal or other privilege, none of which is waived or lost by reason of this transmission. If you are not an intended recipient, you may not use, disseminate, distribute or reproduce such email, any attachments, or any part thereof. If you have received a message in error, please notify the sender immediately and erase all copies of the message and any attachments. Unfortunately, we cannot warrant that the email has not been altered or corrupted during transmission nor can we guarantee that any email or any attachments are free from computer viruses or other conditions which may damage or interfere with recipient data, hardware or software. The recipient relies upon its own procedures and assumes all risk of use and of opening any attachments. ------------------------------

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Geometry layout (packing) algorithm?
by Belcourt, Kenneth 07 Aug '14

07 Aug '14

Hi, I’m looking for an algorithm that will take a largish number (i.e. 10^5) 2d or 3d polygons (mostly parallel-pipeds, e.g. squares and boxes) and partition them into non-overlapping groups where each group contains some number of polygons that might abut along an edge or face, but not overlap. Each box can be represented by a collection of line segments so I thought geometry might have what I’m looking for but I didn’t see anything in a quick scan of the documentation. Does this so called packing (layout) algorithm sound like something already in Boost, Geometry or other library? I have an implementation but what looking to see what other options exist. Thanks. — Noel Belcourt

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[boost] [1.56.0] Release Candidate 3 available
by Marshall Clow 07 Aug '14

07 Aug '14

We've created a third release candidate to fix a one more issue with Boost.Range. The files for 1.56.0 RC3 are available at: http://boost.cowic.de/rc/ As always, the release managers would appreciate it if you download the candidate of your choice and give building it a try. Please report both success and failure, and anything else that is noteworthy. The files (and associated md5s) are: MD5 (./boost_1_56_0_rc3.7z) = b7a72a6a6f487fa445333b4e115c6171 MD5 (./boost_1_56_0_rc3.tar.bz2) = a744cf167b05d72335f27c88115f211d MD5 (./boost_1_56_0_rc3.tar.gz) = 8c54705c424513fa2be0042696a3a162 MD5 (./boost_1_56_0_rc3.zip) = fc16da21d641e03715a4144cb093964e Thanks! -- The release managers

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[date-time] boost::time_duration wrapping
by Justin Muncaster 07 Aug '14

07 Aug '14

Hello, I’m having issues with wrapping of boost::time_duration derived types. I can’t find anywhere in the documentation for when the time_duration types are supposed to wrap around. I have attached some sample source code below. The output is: SecCount = 80000000 is OK. Strange Stranger Problematic SecCount = 80000001 is STRANGE. I expect the output to be SecCount = 80000000 is OK. SecCount = 80000001 is OK. The problem we ran into had to do with seconds and milliseconds having different maximum permissible values. Any idea why boost::posix_time::seconds goes negative at 0x80000001 while milliseconds is not until much later? Thanks, Justin // // test.cpp // #include <boost/date_time.hpp> #include <iostream> using namespace std; using namespace boost::posix_time; //------------------------------------------------------- //------------------------------------------------------- void Strange(long SecCount) { long MilliCount = 1000 * SecCount; bool IsStrange = false; if (SecCount >= 0 && seconds(SecCount).is_negative()) { cout << "Strange" << endl; IsStrange = true; if (!milliseconds(MilliCount).is_negative()) { // If seconds wraps, why doesn't milliseconds? cout << "Stranger" << endl; IsStrange = true; } } if (seconds(SecCount) != milliseconds(MilliCount)) { cout << "Problematic" << endl; IsStrange = true; } if (!IsStrange) { cout << "SecCount = " << SecCount << " is OK." << endl; } else { cout << "SecCount = " << SecCount << " is STRANGE." << endl; } } //------------------------------------------------------- //------------------------------------------------------- int main() { cout << hex; Strange(0x80000000); Strange(0x80000001); return 0; }

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Re: [Boost-users] [ASIO] directory monitor ASIO extension
by Brian Wood 06 Aug '14

06 Aug '14

Niall Douglas writes > * Works reliably on Microsoft Windows (hard), Linux (slightly > easier), BSD and OS X (easiest by far of the lot). > I believe you. Having considered some of your previous comments in a different thread, on kqueue, I ported my code generator from Linux to BSD. I only found relief from a problem I was having by doing so. > Paul Kirth presented on this at C++ Now 2014. It is a surprisingly > tough engineering problem, and requires a design approaching ideal > for it to work at all. Are videos from that conference available yet? -- Brian Ebenezer Enterprises - In G-d we trust. http://webEbenezer.net

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[ASIO] directory monitor ASIO extension
by Szymon Gatner 06 Aug '14

06 Aug '14

Hi, I am going through code of directory monitor ASIO extension by Boris Schäling (http://www.highscore.de/boost/dir_monitor.zip) and I am wondering: what is the benefit of making this piece of code / library an ASIO extension. It just feels like it could be easier to use and implement if it wasn't? I hope I am missing something tho and looking here for enlightenment ;) Regards, Szymon Gatner

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why lockfree/queue.hpp requires has_trivial_assign and has_trivial_destructor to template type T
by 何子杰Hzj_jie 06 Aug '14

06 Aug '14

hi, all,as new to boost, i am looking for a solution to combine boost::lockfree::queue with std::function, i.e. boot::lockfree::queue<std::function>, but unfortunately, the implementation of the lockfree queue required the T to be trivial assignable and trivial destructible.with some basic investigation to the implementation of boost::lockfree::queue, the assignment operator is using when pop or unsynchronized_pop, it calls detail::copy_payload, which is using operator= or constructor and operator=. though overloaded assignment operator may use more time and cause the pop function to wait for longer time, i do not see it would block the logic.for the destruction, queue implementation always calls pool.template destruct instead deallocate, which means even for a default destructor, it will also be called. so is this a defect or by-design behavior of the lockfree queue? thank you in advanced. .Hzj_jie

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[msm] State Machine and Dependency Injection
by Kris 05 Aug '14

05 Aug '14

Hi, Recently I have implemented Dependency Injection library, which I proposed to boost last week (http://boost.2283326.n4.nabble.com/is-there-any-interest-in-a-dependency-in…) Right now I wanted to shared how dependency injection might be integrated with Boost.MSM (eUML) and would really glad for any feedback. Boost.MSM is a great library, unfortunately actions/guards have to have empty constructor and whole logic has to be handled via Finite State Machine. Such approach is hard to maintain and test, so would be great to have possibility to implement action/guards without FSM dependency and with proper dependency injection instead. More information: http://krzysztof-jusiak.github.io/di/boost/libs/di/doc/html/di/examples/int… Hello World: class guard : public euml_action<guard> { public: guard(shared_ptr<data> data = nullptr, shared_ptr<other_data> = nullptr); // default constructor is required by eUML template<typename TEvent> bool operator()(const TEvent&) const; // no FSM dependency }; class action : public euml_action<action> { public: action(shared_ptr<data> data = nullptr, shared_ptr<other_data> = nullptr); // default constructor is required by eUML template<typename TEvent> void operator()(const TEvent&); // no FSM dependency }; class state_machine_ : public state_machine_def<state_machine_> { public: using initial_state = state1; BOOST_MSM_EUML_DECLARE_TRANSITION_TABLE(( state1() + event() [guard()] / action() == state2() ), transition_table) }; using state_machine = back::state_machine< state_machine_ , back::use_dependency_injection // Boost.DI dependency injection policy >; auto sm = di::make_injector().create<state_machine>(); // create state machine / actions, guards and their dependencies will be injected via DI framework sm.process_event(event()); Hot it works? * we do implement actions/guards with any dependencies we need * we add use_dependency_injection policy in state machine definition * we create state machine using dependency injection framework library What MSM with DI actually give us? * actions/guards are really easy to test / code doesn't require FSM dependency - loosely coupled * signature change of actions/guards may not require binding configuration changes (if it's not an interface or it's an interface already bound) * FSM is just a declarative abstraction - we don't need to test it * we can use all DI goods for controlling how dependencies will be injected - see https://github.com/krzysztof-jusiak/di Project (with workings tests): https://github.com/krzysztof-jusiak/msm Comparison between usage of Boost.MSM with DI and without it: http://krzysztof-jusiak.github.io/di/boost/libs/di/doc/html/di/examples/int… Looking forward to hear from you. Any feedback is more than welcome. Cheers, Kris -- View this message in context: http://boost.2283326.n4.nabble.com/msm-State-Machine-and-Dependency-Injecti… Sent from the Boost - Users mailing list archive at Nabble.com.

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