December 2012 - Boost-users - lists.preview.boost.org

Re: [Boost-users] boost msm - differed events
by Kamel Zaarouri, Mr 05 Dec '12

05 Dec '12

Hi guys, I realized that I asked a very unclear question yesterday. I will try to reformulate :) Let's say I have 2 states, an Active state and an Idle state. If I receive some events in Active state I would like to defer them and execute them when I go back to Idle state. But when I go back to Idle State is there a way to chose which previously deferred event to process? or is there a way to prioritize them or even ignore few of them? Thank you!

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C++11, boost::filesystem::path, no std::hash specialization
by Benjamin Kircher 05 Dec '12

05 Dec '12

Hi there, I cannot use boost::filesystem::path with an e.g. unordered_set because std::hash seems not to be specialized for this type. Is this intended? Should I file a bug? Or am I completely misguided? I use 1.52 libraries with -DBOOST_FILESYSTEM_NO_DEPRECATED. I searched the bug database but did not find anything relevant (other than this https://svn.boost.org/trac/boost/ticket/5650 ticket). Thanks in advance, -Benjamin

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Boost.Serialization type-dependent serialization
by Roman Suvorov 05 Dec '12

05 Dec '12

Hi! I have a list of objects of the following structure: > class Obj > { > // a number simple fields > int field1() const; > > // ... > > // reference to an object containing large amount of data > const blob_type & mega_blob() const; > }; The list is to be serialized in the following way: 1) simple fields of each object are to be serialized into a single xml file; 2) mega_blobs' are to be serialized into separate binary files. The idea of doing it is to write custom archive that has operator<< specialized for blob_type which does the magic. Following the Boost.Serialization reference (http://www.boost.org/doc/libs/1_52_0/libs/serialization/doc/archive_referen…), I wrote the code in order to proof the concept: http://pastebin.com/ekbXXvxF My test project is built using CMake and G++-4.6.3 (Debian Wheezy) (that seems to be ok - other code that uses Boost.Serialization compiles well): http://pastebin.com/WVRUKLD2 As a result I get the following linker errors: http://pastebin.com/rM05nkqw The questions: 1) am I using xml_oarchive_impl wrong way or that problem is not boost-related? 2) maybe there are more elegant ways of solving my task? Cheers, Suvorov Roman.

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Re: [Boost-users] Boost-users Digest, Vol 3288, Issue 1
by Shcherbina Vladimir 05 Dec '12

05 Dec '12

Hi, Could you try it with MS compiler and any release prior to the 1.52.0? -----Original Message----- From: boost-users-bounces(a)lists.boost.org [mailto:boost-users-bounces@lists.boost.org] On Behalf Of boost-users-request(a)lists.boost.org Sent: 04 December 2012 17:29 To: boost-users(a)lists.boost.org Subject: Boost-users Digest, Vol 3288, Issue 1 Send Boost-users mailing list submissions to boost-users(a)lists.boost.org To subscribe or unsubscribe via the World Wide Web, visit http://lists.boost.org/mailman/listinfo.cgi/boost-users or, via email, send a message with subject or body 'help' to boost-users-request(a)lists.boost.org You can reach the person managing the list at boost-users-owner(a)lists.boost.org When replying, please edit your Subject line so it is more specific than "Re: Contents of Boost-users digest..." Today's Topics: 1. Re: Boost 1.49.0 compilation issue (Marshall Clow) 2. Re: boost msm - Multiple differed events (Kamel Zaarouri, Mr) 3. [serialization] versioning for class nested within template class (Gabriel Redner) 4. Re: Asio and software interrupts (Steve Lorimer) 5. Spirit guidance needed (Arkadiy and Marina Vertleyb) 6. [boost][polygon]Errors with minkowski sum (renaud lepere) 7. Re: Spirit guidance needed (Igor R) 8. Experience with dealing with warnings from the Clang toolset? (Paul A. Bristow) ---------------------------------------------------------------------- Message: 1 Date: Mon, 3 Dec 2012 09:29:59 -0800 From: Marshall Clow <mclow.lists(a)gmail.com> To: boost-users(a)lists.boost.org Subject: Re: [Boost-users] Boost 1.49.0 compilation issue Message-ID: <BA420D66-6A77-4CF9-AB4C-E1005A770684(a)gmail.com> Content-Type: text/plain; charset=us-ascii On Dec 2, 2012, at 1:47 AM, Shcherbina Vladimir <Vladimir.Shcherbina(a)elbitsystems.com> wrote: > I tried to compile this boost dependent class with VS2008 and VS2010 > (error lines are in bold) Another data point: I was able to successfully compile your code with clang. and the 1.52.0 release. -- Marshall Marshall Clow Idio Software <mailto:mclow.lists@gmail.com> A.D. 1517: Martin Luther nails his 95 Theses to the church door and is promptly moderated down to (-1, Flamebait). -- Yu Suzuki ------------------------------ Message: 2 Date: Mon, 3 Dec 2012 21:08:57 +0000 From: "Kamel Zaarouri, Mr" <kamel.zaarouri(a)mail.mcgill.ca> To: "boost-users(a)lists.boost.org" <boost-users(a)lists.boost.org> Subject: Re: [Boost-users] boost msm - Multiple differed events Message-ID: <E7E49CA8DA97024ABF8B81BBF85E325412D63A(a)EXMBX2010-3.campus.MCGILL.CA> Content-Type: text/plain; charset="us-ascii" Hi Guys, Let's say that we have 2 states, S1 and S2. with this transition table: S1 -> S2 on event Es2 S2 -> S1 on event Es1 also let's say that S1 can also accept Ev1 and Ev2 but S2 cannot accept them so it differs them. Now when let's say that S2 receives 2 events Ev1 and Ev2 and differs them. Now, when S2 goes back to S1 would S1 handle both events in order? or how does it work? Thanks, ------------------------------ Message: 3 Date: Mon, 3 Dec 2012 17:51:40 -0500 From: Gabriel Redner <gredner(a)gmail.com> To: boost-users <boost-users(a)lists.boost.org> Subject: [Boost-users] [serialization] versioning for class nested within template class Message-ID: <CAO0m-H+t-bfAOe7JoV27MEMeHPXs6pVzDV9yqJC1Csp2Av6ESA(a)mail.gmail.com> Content-Type: text/plain; charset=windows-1252 Hi folks, I am having trouble incrementing the serialization version of a regular class nested within a template class. I'm not sure if the problem is with boost or with my own understanding of the issue. My code looks like: ============================== template <typename A, typename B> struct Foo { struct Bar { int data1; int data2; private: friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, unsigned int version) { ar & data1; if (version >= 2) { ar & data2; } else { data2 = 0; } } }; }; ============================== My attempt at setting the version looks like: ============================== namespace boost { namespace serialization { template <typename A, typename B> struct version<typename Foo<A, B>::Bar> { BOOST_STATIC_CONSTANT(unsigned int, value = 2); }; } // namespace serialization } // namespace boost ============================== However, g++ gives an error: ============================== main.cpp:31:8: error: template parameters not used in partial specialization: main.cpp:31:8: error: ?A? main.cpp:31:8: error: ?B? ============================== Strangely, clang 3.0 compiles the code but issues some warnings: ============================== main.cpp:31:8: warning: class template partial specialization contains template parameters that can not be deduced; this partial specialization will never be used struct version<typename Foo<A, B>::Bar> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.cpp:30:20: note: non-deducible template parameter 'A' template <typename A, typename B> ^ main.cpp:30:32: note: non-deducible template parameter 'B' template <typename A, typename B> ^ 1 warning generated. ============================== I'd appreciate any pointers! Thanks, -Gabe ------------------------------ Message: 4 Date: Tue, 4 Dec 2012 10:17:33 +1100 From: Steve Lorimer <steve.lorimer(a)gmail.com> To: boost-users(a)lists.boost.org Subject: Re: [Boost-users] Asio and software interrupts Message-ID: <CAE-NPOiR0Z3rGhmfBftGxpRLrJHTBW=6eMjGac27SaW+OvgJVw(a)mail.gmail.com> Content-Type: text/plain; charset="iso-8859-1" On 4 December 2012 01:51, Joseph Sulewski <joemacher(a)gmail.com> wrote: > *When I call socket->bind I provide it with an endpoint. When I > create the endpoint I'm currently using the multicast address, what > should I use for the address? * > If you bind to INADDR_ANY then the OS will use its ip routing tables to work out which the best local nic to use is. You can force it to use a specific local nic by providing its address. Most applications will use INADDR_ANY *If I'm binding to multiple multicast addresses it doesn't make sense to > bind to one of them.* > Because UDP is connectionless there is no way for the kernel / network stack to know which pid to deliver datagrams to for a particular port unless you bind your socket's file descriptor to that port. (note, if you want to allow other file descriptors to be able to bind to that port you need to set SO_REUSEADDR to 1) > *Finally, it appears I can join multiple multicast groups but they > need to be the same port. Is this correct?* > The reason for this is as my previous point above. What you would do is create as many sockets as there are different ports, and have each socket join the multicast addresses which are on that port > >

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[Filesystem] Movable fstreams
by Szymon Gatner 04 Dec '12

04 Dec '12

Hi, Could move (via boost.move) support be added to file streams provided by filesystem library? Would be very useful when returning for example ifstream from function. Cheers, Simon -- Szymon Gatner The Lordz Games Studio www.thelordzgamesstudio.com

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Boost.Math - Statistical Distribution Explorer - updated to Boost 1.52
by Paul A. Bristow 04 Dec '12

04 Dec '12

Just to note that I have recently updated the Microsoft Windows C# 'app' that allows one to explore various properties of statistical distributions and calculate their Cumulative Distribution Function CDF, Probability Distribution Function PDF, or quantiles/percentiles. This revision includes some new distributions and all the bug fixes and improvements in Boost.Math for 1.52. I have also now aligned the application version numbering with Boost release numbering. For full information and download http://sourceforge.net/projects/distexplorer/ It works on all the 'this-millennium' versions of Windows. If anyone knows how to produce a *nix version, please contact me. Paul --- Paul A. Bristow, Prizet Farmhouse, Kendal LA8 8AB UK +44 1539 561830 07714330204 pbristow(a)hetp.u-net.com

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Spirit guidance needed
by Arkadiy and Marina Vertleyb 04 Dec '12

04 Dec '12

Hi all, Can somebody direct me to a part/facility inside the Spirit library to do the following: I need to pre-parce a boolean expression (once) and save it somewhere. Then I need to evaluate this expression (many times, performance important) based on different values of tokens. Will Spirit.Classic do? Or do I need to use any of the newer libraries inside Spirit? Thanks for any help. Arkadiy

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[boost][polygon]Errors with minkowski sum
by renaud lepere 04 Dec '12

04 Dec '12

I need to implement robust minkowski sum operations on polygons. I have seen that this could be implemented easily using boost::polygon, the tutorial is here http://www.boost.org/doc/libs/1_52_0/libs/polygon/doc/gtl_minkowski_tutoria… The example works fine, however i need more precision than "int" (32 bits on my plateform win32-msvc10-32bits). I tried to replace to replace int -> double typedef boost::polygon::point_data< int > point; with typedef boost::polygon::point_data< double > point; But this leads to strange errors deep into the code (operator< is "bad") if (!_Pred(_Left, _Right)) return (false); else if (_Pred(_Right, _Left)) _DEBUG_ERROR2("invalid operator<", _File, _Line); called after scan_data_.insert(*insert_itr); // line 1197 in scan_arbitrary.hpp What can i do to avoid it, if i use "long long" type it works but it sends a lot of warning at compile time. Any idea of what i should do ? Is "double" type supported ?

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Asio and software interrupts
by Joseph Sulewski 03 Dec '12

03 Dec '12

Hello, I’m use the Boost::Asio libraries to read data from multicast sockets. This is a high rate application that needs to listen to data coming on a large number of multicast addresses (up to 500 different addresses). I would like to funnel all the multicast traffic to a single class where the data can get handled very quickly. I have the code working now using the socket->async_receive_from() method but the system is getting bogged down handling a large number of software interrupts. 51% of the CPU time is spent handling software interrupts. I create each multicast socket (up to 500 of them) like so: socket = new udp::socket(io_service); socket->open(listenEndPoint.protocol()); socket->set_option(boost::asio::ip::udp::socket::resuse_address(true)); socket->bind(listenEndPoint); socket->set_option(boost::asio::ip::multicast::join_group(multicastAddress.to_v4())); Slightly after that I register for data like so: socket->async_receive_from(buffer,senderEndPoint,boost::bind(&EthernetCapture::receiveData,this,boost::asio::placeholders::bytes_transferred)); Is there a more efficient way to receive multicast data without incurring so many software interrupts? By the way this is for an application to run on 32 bit Linux for an embedded application. Thanks

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[serialization] versioning for class nested within template class
by Gabriel Redner 03 Dec '12

03 Dec '12

Hi folks, I am having trouble incrementing the serialization version of a regular class nested within a template class. I'm not sure if the problem is with boost or with my own understanding of the issue. My code looks like: ============================== template <typename A, typename B> struct Foo { struct Bar { int data1; int data2; private: friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, unsigned int version) { ar & data1; if (version >= 2) { ar & data2; } else { data2 = 0; } } }; }; ============================== My attempt at setting the version looks like: ============================== namespace boost { namespace serialization { template <typename A, typename B> struct version<typename Foo<A, B>::Bar> { BOOST_STATIC_CONSTANT(unsigned int, value = 2); }; } // namespace serialization } // namespace boost ============================== However, g++ gives an error: ============================== main.cpp:31:8: error: template parameters not used in partial specialization: main.cpp:31:8: error: ‘A’ main.cpp:31:8: error: ‘B’ ============================== Strangely, clang 3.0 compiles the code but issues some warnings: ============================== main.cpp:31:8: warning: class template partial specialization contains template parameters that can not be deduced; this partial specialization will never be used struct version<typename Foo<A, B>::Bar> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ main.cpp:30:20: note: non-deducible template parameter 'A' template <typename A, typename B> ^ main.cpp:30:32: note: non-deducible template parameter 'B' template <typename A, typename B> ^ 1 warning generated. ============================== I'd appreciate any pointers! Thanks, -Gabe

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