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

Is boost::this_thread::sleep_for interruption point?
by Serg Gulko 23 May '13

23 May '13

Hello! According to documentation(v 1.50.0) call boost::this_thread::sleep_for can be interrupted. For some reason this functionality not works for me. Here is code sample: //Simple thread function void Test::worker(int delay) { try { boost::this_thread::sleep_for(boost::chrono::milliseconds(delay)); cout << "Doing some work" << endl; } catch (boost::thread_interrupted const& e) { cout << "INTERRUPTED" << endl; } } //Far in the code boost::thread workerThread(boost::bind(&Test::worker, this, 1200)); boost::this_thread::sleep(boost::posix_time::milliseconds(30)); workerThread.interrupt(); boost::this_thread::sleep(boost::posix_time::milliseconds(1500)); I always getting 'Doing some work'... -- View this message in context: http://boost.2283326.n4.nabble.com/Is-boost-this-thread-sleep-for-interrupt… Sent from the Boost - Users mailing list archive at Nabble.com.

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Re: [Boost-users] [CMake] [boost][b2] Differenciate 32bit and 64 bit binaries when using CMake.
by Klaim - Joël Lamotte 16 Apr '13

16 Apr '13

Júlio Hoffimann said: > > I don't know if i understood correctly, but you can set the library > directory by hand, please refer to > /usr/share/cmake-<version>/Modules/FindBoost.cmake, in particular the > variable BOOST_LIBRARYDIR. On Thu, Oct 11, 2012 at 1:29 PM, Miller, Frank <FMiller(a)sjm.com> wrote: > A simple solution would be to install only the 64bit version of boost > into a new directory and change the environment variable to point there. > Then FindBoost will only be able to see the version you want. > Thanks, this will solve my immediate problem, but it don't solve it in general. (I will use it though, so thanks) I can't guarantee where the boost libraries are installed, that's why I use FindBoost. My current understanding is that boost don't have a specific default lib dir for different address models, which is the source of the problem as FindBoost script can't rely on a protocol to find these lib files. Am I correct? Joel Lamotte

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can't get first example in boost tutorial to work
by 7stud 11 Mar '13

11 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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chaining functions input output
by MM 19 Feb '13

19 Feb '13

Hello, i have these 2 functions provided to me and I wonder whether they can somehow be chained without using intermediary memory? http://codepad.org/tTwkUQhp Rds, MM

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regular expression to extract numbers
by Neil Sutton 29 Jan '13

29 Jan '13

Hi, I am new to using boost and am trying to learn basics so I can use regex features in my code. In my test program, I want a function to simply extract some numbers that follow after a certain string pattern and then to read those numbers into a vector. This is an outline of what i would like to do: // function definition #ifndef findnumbers.h #define findnumbers.h #include <string> #include <fstream> #include <vector> #include <boost/regex.hpp> #endif void findnumbers (ifstream& afile) { // assume file is opened in main - i have passed a reference boost::regex expression ( ....having trouble with this); // search for matches - there will be a fixed number of numbers e.g 10 std::string const_iterator start, end; start = afile.begin( ); end = afile.end( ); std::vector<int> results; boost::match_results<std::vector<int>::const_iterator> what; for(int count = 0; count !=10; count++) { boost::regex_search(start,end,what,expression) { //if a number is found place in the vector results.push_back(count); } So the first problem I have is defining a correct expression. The pattern has the format "sometext>NUMBERS<sometext" newline. The NUMBERS may be one or two digits combined and the pattern is repeated 10 times. I have searched the archives and tried to build something based on the examples I have read, but cannot seem to find a working solution. Can anyone help please in defining an expression? I do not need a solution to my function overall as I should be able to write it correctly once I know how to define the pattern. Kind regards

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boost asio disign
by Christer Borgqvist 24 Jan '13

24 Jan '13

Hello, how can I design an application that will have a http server like HTTP Server 3 example, but also x number of tcp clients connecting to a server, client must connect to the server before the http server is active, if client is idle with a timer events send an 'I'm here' in every 10 seconds, i tink i have to put the tcp client on a list or ?. Data is received by the http server get the client from list, if non available wait for x amount of time, if time elapsed return incomming data, else, parsing on incomming data, send to tcp server, parse response data put the client back on the list, send response on http, when sending data via tcp client reset the timer. I have the http server working but how do I do with the tcp client, design the threads, should there be only one io_service?, I dont now, im lost! Appreciate all the help. /Christer

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[Program Options] terminate parsing after first positional argument
by Stuart Pook 22 Jan '13

22 Jan '13

Hello, How can I tell Boost Program Options to stop parsing the arguments as soon as it finds a positional argument? I'd like to be able to parse the argument list "-v chmod -R -v 600 foo" as having one argument for my program (-v) and the rest as a std::vector of std::string (including the -v). In the attached program I have tried 2 different approaches. The first uses multitoken with the arguments "--command date -u -v", it fails because "-u" isn't known. The second uses collect_unrecognized with "chmod -R -v 600", it doesn't work because -v is interpreted by boost and doesn't end up in the vector. As someone said back in 2005, perhaps I'm trying to write xargs: http://thread.gmane.org/gmane.comp.lib.boost.user/9529/focus=9641 I know that I can ask my users to write a.out -v -- chmod -R -v 600 foo but I don't want to do that. I want them to write "a.out -v chmod -R -v 600 foo". The first positional argument should should tell boost to stop processing. Another slightly different question. If I have a multitoken option that takes doubles how can I get it to accept negative values? If I give my program "--floats 1 8 -4 6" where --floats starts a multitoken option that accepts double, I get an exception saying that "-4" is an unknown option. thanks Stuart This is what my test program gives me with boost 1.50: argv: dd --command date -u -v unrecognised option '-u' Allowed options: -v [ --verbose ] verbose --command arg command to run 2nd try argv: dd chmod -R -v 600 I'm verbose v: chmod -R 600 3rd try argv: dd --floats 1 8 -4 6 unrecognised option '-4' Allowed options: -v [ --verbose ] verbose -f [ --floats ] arg numbers and my program (formatted to fit in 80 characters) #include <boost/program_options.hpp> #include <boost/range/algorithm.hpp> #include <boost/program_options/parsers.hpp> #include <boost/program_options/options_description.hpp> #include <iostream> namespace po = boost::program_options; #define nelements(a) (sizeof (a) / sizeof (a)[0]) void print(char const * * b, char const * * e) { std::cout << "argv: "; std::copy(b, e, std::ostream_iterator<char const *>(std::cout, " ")); std::cout << std::endl; } int main(int argc, char ** argv) { { bool verbose; std::vector<std::string> command; po::options_description desc("Allowed options"); desc.add_options() ("verbose,v", po::bool_switch(&verbose)->default_value(false), "verbose") ("command", po::value<std::vector<std::string> >(&command) ->multitoken(), "command to run") ; char const * args[] = { "dd", "--command", "date", "-u", "-v", 0 }; print(args, args + nelements(args) - 1); po::variables_map vm; try { po::store(po::command_line_parser(nelements(args) - 1, args) .options(desc).run(), vm); po::notify(vm); if (verbose) std::cout << "I'm verbose\n"; std::cout << "command: "; boost::copy(command, std::ostream_iterator<std::string>(std::cout, " ")); std::cout << std::endl; } catch (boost::program_options::unknown_option & x) { std::cerr << x.what() << "\n" << desc << "\n"; } } std::cout << "2nd try\n"; { bool verbose; po::options_description desc("Allowed options"); desc.add_options() ("verbose,v", po::bool_switch(&verbose)->default_value(false), "verbose") ; char const * args[] = { "dd", "chmod", "-R", "-v", "600", 0 }; print(args, args + nelements(args) - 1); po::variables_map vm; po::parsed_options parsed = po::command_line_parser(nelements(args) - 1, args). options(desc).allow_unregistered().run(); try { po::store(parsed, vm); } catch (boost::program_options::unknown_option & x) { std::cerr << x.what() << "\n" << desc << "\n"; exit(2); } po::notify(vm); if (verbose) std::cout << "I'm verbose\n"; std::cout << "v: "; std::vector<std::string> v = po::collect_unrecognized( parsed.options, po::include_positional); boost::copy(v, std::ostream_iterator<std::string>(std::cout, " ")); std::cout << std::endl; } std::cout << "3rd try\n"; { bool verbose; std::vector<double> f; po::options_description all("Allowed options"); all.add_options() ("verbose,v", po::bool_switch(&verbose)->default_value(false), "verbose") ("floats,f", po::value<std::vector<double> >(&f)->multitoken(), "numbers") ; char const * args[] = { "dd", "--floats", "1", "8", "-4", "6", 0 }; print(args, args + nelements(args) - 1); po::variables_map vm; try { po::store(po::command_line_parser(nelements(args) - 1, args) .options(all).run(), vm); po::notify(vm); if (verbose) std::cout << "I'm verbose\n"; std::cout << "floats: "; boost::copy(f, std::ostream_iterator<double>(std::cout, " ")); std::cout << std::endl; } catch (boost::program_options::unknown_option & x) { std::cerr << x.what() << "\n" << all << "\n"; } } }

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[MultiArray, Intrusive] Instantiating a multi_array of intrusive lists as a class member
by Jiri Vyskocil 08 Jan '13

08 Jan '13

Hello, I want to try Boost Intrusive list instead of std::list in a performance and memory critical part of code. I have a Domain object, which contains a boost::multi_array of cells. each cell contains a list of particles std::list<Particle>. This sample code works as expected (std::list): #include <list> #include <iostream> #include <boost/multi_array.hpp> struct Particle { unsigned number; Particle(unsigned n){ number = n; } }; typedef std::list<Particle> ParticleList; typedef boost::multi_array<ParticleList, 3> ParticleArray; class Domain { public: ParticleArray particles; Domain(int x, int y, int z) : particles(boost::extents[x][y][z]) { } }; int main(){ Domain* dom = new Domain(10,10,10); dom->particles[5][5][5].push_back(Particle(1)); std::cout << dom->particles[5][5][5].front().number << std::endl; return 0; } When I try to swap the std::list for an intrusive list, I get a compile error on Domain instantiation. Minimal code leading to the error: #include <boost/intrusive/list.hpp> #include <boost/multi_array.hpp> typedef boost::intrusive::list_base_hook<> BaseHook; struct Particle : BaseHook { unsigned number; }; typedef boost::intrusive::list<Particle> ParticleList; typedef boost::multi_array<ParticleList, 3> ParticleArray; class Domain { public: ParticleArray particles; Domain(int x, int y, int z) : particles(boost::extents[x][y][z]) { } }; int main(){ Domain* dom = new Domain(10,10,10); return 0; } When I try to compile the above code, gcc tells me: In file included from /usr/lib/gcc/x86_64-pc-linux-gnu/4.6.3/include/g++-v4/bits/stl_tempbuf.h:61:0, from /usr/lib/gcc/x86_64-pc-linux-gnu/4.6.3/include/g++-v4/bits/stl_algo.h:64, from /usr/lib/gcc/x86_64-pc-linux-gnu/4.6.3/include/g++-v4/algorithm:63, from /usr/include/boost/move/move.hpp:37, from /usr/include/boost/intrusive/detail/has_member_function_callable_with.hpp:22, from /usr/include/boost/intrusive/detail/memory_util.hpp:112, from /usr/include/boost/intrusive/pointer_traits.hpp:26, from /usr/include/boost/intrusive/detail/utilities.hpp:17, from /usr/include/boost/intrusive/list_hook.hpp:19, from /usr/include/boost/intrusive/list.hpp:20, from intrusive.cc:1: /usr/lib/gcc/x86_64-pc-linux-gnu/4.6.3/include/g++-v4/bits/stl_construct.h: In function ‘void std::_Construct(_T1*, const _T2&) [with _T1 = boost::intrusive::list<Particle>, _T2 = boost::intrusive::list<Particle>]’: /usr/lib/gcc/x86_64-pc-linux-gnu/4.6.3/include/g++-v4/bits/stl_uninitialized.h:189:3: instantiated from ‘static void std::__uninitialized_fill_n<_TrivialValueType>::__uninit_fill_n(_ForwardIterator, _Size, const _Tp&) [with _ForwardIterator = boost::intrusive::list<Particle>*, _Size = long unsigned int, _Tp = boost::intrusive::list<Particle>, bool _TrivialValueType = false]’ /usr/lib/gcc/x86_64-pc-linux-gnu/4.6.3/include/g++-v4/bits/stl_uninitialized.h:225:7: instantiated from ‘void std::uninitialized_fill_n(_ForwardIterator, _Size, const _Tp&) [with _ForwardIterator = boost::intrusive::list<Particle>*, _Size = long unsigned int, _Tp = boost::intrusive::list<Particle>]’ /usr/include/boost/multi_array.hpp:477:5: instantiated from ‘void boost::multi_array<T, NumDims, Allocator>::allocate_space() [with T = boost::intrusive::list<Particle>, long unsigned int NumDims = 3ul, Allocator = std::allocator<boost::intrusive::list<Particle> >]’ /usr/include/boost/multi_array.hpp:186:5: instantiated from ‘boost::multi_array<T, NumDims, Allocator>::multi_array(const boost::detail::multi_array::extent_gen<NumDims>&) [with T = boost::intrusive::list<Particle>, long unsigned int NumDims = 3ul, Allocator = std::allocator<boost::intrusive::list<Particle> >]’ intrusive.cc:18:49: instantiated from here /usr/lib/gcc/x86_64-pc-linux-gnu/4.6.3/include/g++-v4/bits/stl_construct.h:84:7: error: passing ‘const boost::intrusive::list<Particle>’ as ‘this’ argument of ‘boost::intrusive::list<T, O1, O2, O3>::operator boost::rv<boost::intrusive::list<T, O1, O2, O3> >&() [with T = Particle, O1 = boost::intrusive::none, O2 = boost::intrusive::none, O3 = boost::intrusive::none]’ discards qualifiers [-fpermissive] This is just a minimal sample code to trigger an error. In the actual code, both Domain and Particle objects are more complicated. The last line of error output is sligtly different: /usr/lib/gcc/x86_64-pc-linux-gnu/4.6.3/include/g++-v4/bits/stl_construct.h:84:7: error: no matching function for call to ‘boost::intrusive::list<Particle>::list(const boost::intrusive::list<Particle>&)’ followed by a note with a list of candidate functions. If I define the multi_array so that it contains pointers to ParticleArray, i.e.: typedef boost::multi_array<ParticleList*, 3> ParticleArray; there seems to be no benefit over the std::list approach, since I have to hold the additional pointer. In a test simulation, this variant eats about 10% more RAM, which is of concern in our situation. Any ideas how to replace std::list with boost::intrusive::list in a multi_array in a way which wouldn't consume more memory than the std::list approach? (I would want to see if it also brings the much needed performance benefit) Jiri Vyskocil

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[Polygon] Boolean (Clipping) performance
by kusogray 03 Jan '13

03 Jan '13

Hi there, I input 200,000 to both polygon set A and B, with each polygon contains 5~8 points then do the A^B; however, this instruction cost about *30 minutes.* my question is: I thought the O(n logn) algorithm with n ~ 1,000,000 just cost about at most 2 or 3 mins I checked the XOR AND OR result is correct, but the performance is weird, did I do anything wrong or misunderstanding? Thanks for reading this! -- View this message in context: http://boost.2283326.n4.nabble.com/Polygon-Boolean-Clipping-performance-tp4… Sent from the Boost - Users mailing list archive at Nabble.com.

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[system] local static and threading in C++03
by Felipe Magno de Almeida 02 Jan '13

02 Jan '13

Hello, Boost.System returns the system_category this way: BOOST_SYSTEM_DECL const error_category & system_category() { static const system_error_category system_category_const; return system_category_const; } But couldn't this make double construction/double free in C++03 systems if system_category is ran concurrently? Regards, -- Felipe Magno de Almeida

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