October 2012 - 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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[statechart] Passing parameters from event to State Local Storage
by Christophe Bourez 16 Nov '16

16 Nov '16

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

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Statechart serialization
by mbrodeur65 04 Mar '15

04 Mar '15

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

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[Thread] Read-write locks
by lfrfly＠icqmail.com 18 Sep '14

18 Sep '14

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

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

22 Jul '14

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

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

14 Mar '14

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

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using boost with net-snmp
by moshe levi 12 Sep '13

12 Sep '13

I wrote an example on how to integrate net-snmp with boost. please checkout http://blog-moshe.blogspot.co.il/

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

06 Sep '13

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

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

20 Aug '13

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

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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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[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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Further Boost.MPI development
by Matthias Troyer 15 Nov '12

15 Nov '12

Dear Boost.MPI users, With the MPI-3 standard having been finalized we want to intensify Boost.MPI development as soon as my crazy teaching schedule this fall gives me time from the middle of next month. With the deprecation of the - little used - official MPI C++ API in MPI-3 Boost.MPI has a chance of becoming a de facto standard C++ API for MPI. We first want to focus on features from MPI-2 and MPI-3 that are widely used or useful. For this purpose I would like to collect suggestions. Can you please reply and mention the functions of MPI that you would most like to see supported by Boost.MPI. Best regards Matthias

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[Locale] MinGW + ICU + cross compiling = wchar errors?
by Jookia 13 Nov '12

13 Nov '12

Hello! I'm trying to compile Boost.Locale 1.51.0 with ICU 1.50 support in x86_64 MinGW-w64 4.7.2. So to start off, I have a structure of all my libs, includes and whatnot at /home/jookia/Programming/mingw64. I've built ICU using this command and installed it: CXXFLAGS=-fpermissive ../configure --prefix=/home/jookia/Programming/mingw64/ --host x86_64-w64-mingw32 --with-cross-build=/home/jookia/Programming/local/icu/source/build --enable-static --enable-shared --with-data-packaging=archive --with-library-bits=64 Building Boost uses this user-config: using gcc : 4.7 : x86_64-w64-mingw32-g++ : <rc>x86_64-w64-mingw32-windres <archiver>x86_64-w64-mingw32-ar <compileflags>-I/home/jookia/Programming/mingw64/include/ <linkflags>-L/home/jookia/Programming/mingw64/lib/ ; and this command: bjam threadapi=win32 target-os=windows variant=release threading=multi link=shared runtime-link=shared --prefix=/home/jookia/Programming/mingw64 --user-config=user-config.jam --without-python --without-mpi --layout=tagged -sNO_BZIP=1 -sNO_ZLIB=1 install In order to try and build Boost.Locale I've patched its Jamfile to remove the shared libstdc++ stuff as MinGW doesn't seem to support it, and also rename all of the searched-lib <name>s to their MSVC equivalents so I can find those. The command it used to build is this (stuff omitted to save space): "x86_64-w64-mingw32-g++" "-Wl,--out-implib,bin.v2/libs/locale/build/.../libboost_locale-mt.dll.a" -o "bin.v2/libs/locale/build/.../libboost_locale-mt.dll" -Wl,-h -Wl,libboost_locale-mt.dll -shared -Wl,--start-group ... -Wl,-Bstatic -Wl,-Bdynamic -licuuc -licuin -licudt -liconv -Wl,--end-group -L/home/jookia/Programming/mingw64/lib/ -mthreads Compiling works fine up until linking, where it gives a few errors like this (paths and mangled names omitted to save sapce): bin.v2/.../formatter.o:formatter.cpp:(... undefined reference to `icu_50::UnicodeString::UnicodeString(wchar_t const*, int)' Is there any solution to this or is this something to do with MinGW's lack of support for wchars? Thanks, Jookia.

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Linking problems with boost serialization and MinGW
by Florian Burkart 05 Nov '12

05 Nov '12

Hi, I am having a bit of trouble linking to boost serialization with MinGW. If I don't include -lboost_serialization-mgw46-mt-d-1_50 I get loads of undefined references, however, if I do include it, most disappear but I still get some, namely I get RDebug/libFlamLib.a(Common_Collector.o): In function `ZN5boost7archive21basic_text_oprimitiveISoE4saveINS0_14object_id_typeEEEvRKT_': /Sys/boost/MinGW32/boost_1_50_0/include/boost-1_50/boost/archive/basic_text_oprimitive.hpp:89: undefined reference to `boost::archive::archive_exception::archive_exception(boost::archive::archive_exception::exception_code, char const*, char const*)' RDebug/libFlamLib.a(Common_Collector.o): In function `ZN5boost7archive21basic_text_oprimitiveISoE4saveINS0_21object_reference_typeEEEvRKT_': /Sys/boost/MinGW32/boost_1_50_0/include/boost-1_50/boost/archive/basic_text_oprimitive.hpp:89: undefined reference to `boost::archive::archive_exception::archive_exception(boost::archive::archive_exception::exception_code, char const*, char const*)' RDebug/libFlamLib.a(Common_Collector.o): In function `ZN5boost7archive21basic_text_oprimitiveISoE4saveINS0_13class_id_typeEEEvRKT_': /Sys/boost/MinGW32/boost_1_50_0/include/boost-1_50/boost/archive/basic_text_oprimitive.hpp:89: undefined reference to `boost::archive::archive_exception::archive_exception(boost::archive::archive_exception::exception_code, char const*, char const*)' RDebug/libFlamLib.a(Common_Collector.o): In function `ZN5boost7archive21basic_text_oprimitiveISoE4saveINS0_23class_id_reference_typeEEEvRKT_': /Sys/boost/MinGW32/boost_1_50_0/include/boost-1_50/boost/archive/basic_text_oprimitive.hpp:89: undefined reference to `boost::archive::archive_exception::archive_exception(boost::archive::archive_exception::exception_code, char const*, char const*)' RDebug/libFlamLib.a(Common_Collector.o): In function `ZN5boost7archive21basic_text_oprimitiveISoE4saveINS0_13tracking_typeEEEvRKT_': /Sys/boost/MinGW32/boost_1_50_0/include/boost-1_50/boost/archive/basic_text_oprimitive.hpp:89: undefined reference to `boost::archive::archive_exception::archive_exception(boost::archive::archive_exception::exception_code, char const*, char const*)' RDebug/libFlamLib.a(Common_Collector.o):/Sys/boost/MinGW32/boost_1_50_0/include/boost-1_50/boost/archive/basic_text_oprimitive.hpp:89: more undefined references to `boost::archive::archive_exception::archive_exception(boost::archive::archive_exception::exception_code, char const*, char const*)' follow Basically they all refer to "`boost::archive::archive_exception::archive_exception". boost serialization built fine with .\b2.exe --prefix=c:\Sys\boost\MinGW32\boost_1_50_0 toolset=gcc address-model=32 --with-serialization install The same code compiles and links just fine with gcc on linux and MSVC on windows. I haven't isolate the issue yet, so am afraid can't give a reproducible sample, but any ideas so far? Maybe look familiar? Thanks, Florian

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[Filesystem] Reverse traversal of boost::filesystem::path::const_iterator?
by Nat Linden 02 Nov '12

02 Nov '12

I've stumbled across some code in our code base that wants to walk up a fixed number of containing parent directories from the starting path. (It's in a Mac application bundle nested within another.) boost::filesystem::path::[const_]iterator is described as bidirectional. But boost::filesystem::path has no rbegin() or rend(). In libs/filesystem/test/path_test.cpp's iterator_tests(), I see, for a path variable named itr_ck, use of boost::prior(itr_ck.end()). That suggests that usage of this form would be legal: path mypath = /* ...something... */; for (path::const_iterator rcomp(mypath.end()), rend(mypath.begin()); rcomp != rend; --rcomp) { // ... use boost::prior(rcomp) ... } Am I correct? Given the way some containers implement end(), I always feel nervous about decrementing end(). I'm happy to see that Boost.Filesystem's own tests guarantee that usage; but is there anything in the documentation that would have assured me of that?

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boost::heap::skew_heap(1_51_0) ordered_iterator
by imns70 02 Nov '12

02 Nov '12

Hi This question pertains to boost::heap::skew_heap as defined here:- http://www.boost.org/doc/libs/1_51_0/doc/html/boost/heap/skew_heap.html Can you please help me understand what is the complexity of skew heap traversal using ordered_iterator. I am traversing over the heap, using ordered_iterator as shown in code below :- for(bk_heap::ordered_iterator it=buy_heap->ordered_begin();it!=buy_heap->ordered_end();it++) { /// some code here... } I suspect it to be O(n), but just want to make sure. Thanks in advance. -- View this message in context: http://boost.2283326.n4.nabble.com/boost-heap-skew-heap-1-51-0-ordered-iter… Sent from the Boost - Users mailing list archive at Nabble.com.

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[phoenix] Using with Boost.Function.
by Robert Jones 02 Nov '12

02 Nov '12

Can anyone tell me the correct incantation to get the 'Not OK' lines to work? Thx, Rob. #include <boost/function.hpp> #include <boost/phoenix/core.hpp> #include <boost/phoenix/operator.hpp> #include <boost/phoenix/bind/bind_member_variable.hpp> #include <boost/phoenix/bind/bind_function.hpp> #include <boost/function.hpp> #include <list> struct S { int i; }; void f( std::list<S> & l, int i ) { using boost::phoenix::arg_names::_1; using boost::phoenix::arg_names::_2; // OK l.remove_if( bind( & S::i, _1 ) >= i ); *// Not OK.* * boost::function<bool( int, int )> pred = _1 >= _2;* * l.remove_if( bind( pred, _1, i ) );* }

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Iterator Range, sub range of a desired size
by David Kimmel 02 Nov '12

02 Nov '12

Is there a function in BOOST, given a starting point and a desired size, that returns iterators for a (sub) range? For example, given: a boost::circular_buffer which contains: 1 2 3 4 5 6 7 8 9 10 a starting point which is an iterator pointing to 5 and finally a desired size which is an int s = 4 The result of which would be iterators producing: 5 6 7 8 A possible implementation might be this (but I was hoping there was a BOOST version since I can't find an STD algorithm) template <typename Itr> std::pair<Itr, Itr> getWindowDown(Itr begin, Itr end, Itr start, const int windowSize) { // Down first, then up if need be const Itr bottom = (end - start > windowSize) ? (start + windowSize) : (end); const Itr top = (bottom - begin > windowSize) ? (bottom - windowSize) : (begin); return make_pair(top, bottom); } Thanks, -- View this message in context: http://boost.2283326.n4.nabble.com/Iterator-Range-sub-range-of-a-desired-si… Sent from the Boost - Users mailing list archive at Nabble.com.

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bug of boost algorithm library or boost asio?
by kpzhang 01 Nov '12

01 Nov '12

Hi, Apologize if this is not the right place for this mail. This program (it has been narrowed down from a larger program) always crashes after compiled in vs2008 Release(Win32) mode under windows 7. I am not familiar with assembly code and don't know it's a bug of compiler or boost::ends_with or boost::asio::buffers_iterator. It can be compiled and executed with g++ in Ubuntu without any problem. People said it's very unlikely to be compiler's bug, but when compiled in debug moded(or disable optimization), the problem does disappear. I have been stuck with this problem for quite a few hours. Any help is appreciated. Thanks in advance. #include <iostream>#include <string>#include <boost/asio.hpp>#include <boost/algorithm/string.hpp> typedef boost::asio::buffers_iterator<boost::asio::const_buffers_1> iterator_t;typedef boost::iterator_range<iterator_t> range_t;static const std::string LINE_END_MARK = "\r\n"; int main(int argc, char* argv[]){ boost::asio::streambuf _buf; std::ostream os(&_buf); os<<"END\r\n"; iterator_t cursor = boost::asio::buffers_begin(_buf.data()); iterator_t end = boost::asio::buffers_end(_buf.data()); std::ostream_iterator<char> it(std::cout," "); std::copy(LINE_END_MARK.begin(), LINE_END_MARK.end(), it); range_t r(cursor, end); if(!boost::ends_with(r, LINE_END_MARK)) return 0; return 1;}

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C++ Now 2013 Call for Submissions
by Hartmut Kaiser 31 Oct '12

31 Oct '12

---------------------------------------------------------------------------- C++ NOW CONFERENCE 2013 - Aspen CO, USA, May 13-17, 2013, www.cppnow.org ---------------------------------------------------------------------------- CALL FOR SUBMISSIONS -------------------- We invite you to submit session proposals to the 2nd annual C++ Now Conference (Aspen CO, USA, May 13-17, 2013). Building upon the resounding success of C++ Now 2012 and five years of BoostCon, C++ Now 2013 will present leading speakers from the whole C++ community. The C++ Now Conference is dedicated to discussion and education about C++, an open and free language and standard. Our Conference will focus on discussion and education about open source software usage and developments in the C++ developer and user community. To reflect the breadth of the C++ and Boost communities, the conference includes sessions aimed at three constituencies: C++ and Boost end-users, hard-core Boost library and tool developers, and researchers pushing the boundaries of computation. The program fosters interaction and engagement within and across those groups, with an emphasis on hands-on, participatory sessions. As a multi-paradigm language, C++ is a melting pot where the most compelling ideas from other programming communities are blended in powerful ways. Historically, some of the most popular sessions at C++ Now have highlighted these concepts, from DSLs to functional programming to transactional memory and more. Bring your C#, Python, Ruby or Haskell influences to bear in an environment that will broaden their exposure. At C++ Now 2013 we would like to focus on parallel and distributed computing with C++. However, by no means this is intended to restrict the topics of proposals we hope to see. Any other topic related to C++ as outlined below is perfectly fine for submission. IMPORTANT DATES --------------- New proposal submissions due: December 15th, 2013. Proposals decisions sent (tentative program available): January 30th, 2013. Fully scheduled program available: February 24th, 2013. BEST PRESENTATION AWARDS ------------------------ We know how much effort it takes to prepare talks for our conference. For this reason we will award the best presentations in the following categories: Best Presentation, Best Short Presentation, Best Tutorial, and Best Workshop. The awards will be given based on the audience's voting. Each award will include the author's name listed on the cover of the C++ Now website for that year and a plaque containing all the C++ Now conference information. SESSION TOPICS -------------- Topics of interest include, but are not restricted to, the following: * Parallelism in the new C++11 standard * Parallel, distributed and GPGPU topics relating to C++ * C++11 and how it changes life for users and library writers * General tutorial sessions on C++11, the C++11 Standards library, and one or more Boost libraries * In-depth sessions on using specific Boost libraries * Case studies on using Boost * Experts panels * Advanced sessions on implementation techniques used within Boost libraries * Development workshops to extend or enhance existing Boost libraries * Workshops on design process * Infrastructure workshops such as Build tools, Website, Testing * Concepts and Generic Programming * Hardware and infrastructure presentations focused on how libraries can make better use of the technology * Software development tools and their application to C++ and or Boost * Other topics likely to be of great interest to C++ users and developers Interactive and collaborative sessions are encouraged, as this is the style of learning and participation that has proven most successful at such events. Sessions can be tutorial based, with an emphasis on interaction and participant involvement, or workshop based, whether hands-on programming or paper-based, discussion-driven collaborative work. SESSION FORMATS --------------- Presentations Presentations focus on a practitioner's ideas and experience with anything relevant to C++11, Boost and users. Panels Panels feature three or four people presenting their ideas and experiences relating to C++11 and Boost's relevant, controversial, emerging, or unresolved issues. Panels may be conducted in several ways, such as comparative, analytic, or historic. Tutorials Tutorials are sessions at which instructors teach conference participants specific skills relevant to C++11 and Boost. Workshops Workshops provide an active arena for advancements in Boost-relevant topics. Workshops provide the opportunity for experienced practitioners to develop new ideas about a topic of common interest and experience. Author's Corner Presentations These were introduced at BoostCon 2008, and were a great success. They are short (30 minute) sessions, focusing on tips on usage and design. In addition, we're looking to uncover the hidden design gems in Boost libraries. Tool Vendors Presentations We actively encourage tool vendors and ISP's to submit proposals for a special Tool Vendors Session Track aimed at products related to Boost and C++ (compilers, libraries, tools, etc.). Other formats may also be of interest. Don't hold back a proposal just because it doesn't fit into a pigeonhole. SUBMITTING A PROPOSAL --------------------- Standard Sessions are 90 minutes. You may submit a proposal for fractions Or multiples of 90-minutes. Fractional proposals will be grouped into 90 Minute sessions covering related topics. Longer sessions, such as tutorials and classes, will be assigned three hour (i.e. half day), or six hour (i.e. full day) time slots. Please include: * The working title. * Type of session: presentation, panel, tutorial, workshop, authors corner, vendor track, other. * A paragraph or two describing the topic covered, suitable for the conference web site. * Proposed length: 10-20 minute short talks, 45 minutes, 90 minutes, half day, full day. * Alternate lengths, if you are willing to make adjustments: 10-20 minute short-talks, 45 minutes, 90 minutes, half-day, full day. * Audience: users, developers, both. * Level: basic, intermediate, advanced. * A biography, suitable for the conference web site. * Your contact information (will not be made public). SUBMISSION DETAILS ------------------ All submissions should be made through the EasyChair conference management system: http://www.easychair.org/conferences/?conf=cppnow2013. If you have not already registered at EasyChair, you will need to do so in order to submit your proposal. All submissions will go through a peer review process. Authors are invited (but are not required) to submit PDF versions of full papers of up to 10 pages in ACM conference proceedings format (see http://www.acm.org/sigs/publications/proceedings-templates) The full papers are not required unless you want them published in the proceedings. All accepted proposals will be made available in the Association for Computing Machinery (ACM) Digital Library (approval pending). Best papers, after further reviews, will be considered to be book chapters or journal articles in a renowned journal. The session materials go on the C++ Now website and will be available to attendees. For general information on the C++ Now 2013 paper submission or the scope of technical papers solicited; please refer to the conference website at www.cppnow.org. For any other questions about the submission process or paper format, please contact the Program Committee at cppnow2013(a)easychair.com. If you have any technical problems with EasyChair, please contact EasyChair for help. Note: Presenters must agree to grant a non-exclusive perpetual license to publish submitted materials, either electronically or in print, in any media related to C++ Now. Hartmut Kaiser, email: hartmut.kaiser(a)gmail.com (Program Committee Chair) Dave Abrahams, email: dave(a)boostpro.com (Conference Chair) On behalf of the conference organizers

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lockfree is part of the boost-1.52?
by niXman 31 Oct '12

31 Oct '12

Hi, As I can see, lockfree is in trunk, but in the documentation for boost-1.52 is not said about that. Why? And one more question: How can I determine what lockfree is part of the boost? Is there a macro for this? -- Regards, niXman ___________________________________________________ Dual-target(32 & 64-bit) MinGW compilers for 32 and 64-bit Windows: http://sourceforge.net/projects/mingwbuilds/

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[fusion] Compile Error using BOOST_FUSION_DEFINE_STRUCT_INLINE with VC10 and GCC 4.2.1
by Oswin Krause 31 Oct '12

31 Oct '12

HI, the following code gives a compile error on VC10 and GCC 4.2.1. Clang and GCC 4.7 like it: #include <boost/fusion/sequence.hpp> #include <boost/fusion/include/define_struct_inline.hpp> #include <iostream> template<class T> struct enclosing { BOOST_FUSION_DEFINE_STRUCT_INLINE( employee, (std::string, name) (int, age)) }; int main() { enclosing<int>::employee e; e.name="abc"; std::cout<<boost::fusion::deref(boost::fusion::begin(e)); } complete error mssag on VC10: 1>c:\program files (x86)\boost\boost_1_51\boost\fusion\iterator\deref.hpp(34): error C2504: 'enclosing<T>::employee::employee_iterator<boost_fusion_uglified_Seq,N>::deref<boost_fusion_uglified_T>': Basisklasse undefiniert 1> with 1> [ 1> T=int, 1> boost_fusion_uglified_Seq=enclosing<int>::employee, 1> N=0 1> ] 1> and 1> [ 1> boost_fusion_uglified_T=enclosing<int>::employee::employee_iterator<enclosing<int>::employee,0> 1> ] 1> c:\program files (x86)\boost\boost_1_51\boost\fusion\iterator\deref.hpp(53): Siehe Verweis auf die Instanziierung der gerade kompilierten Klassen-template "boost::fusion::extension::deref_impl<boost::fusion::iterator_facade_tag>::apply<Iterator>". 1> with 1> [ 1> Iterator=enclosing<int>::employee::employee_iterator<enclosing<int>::employee,0> 1> ] 1> c:\users\ulfi\documents\visual studio 2010\projects\test\test\test.cpp(18): Siehe Verweis auf die Instanziierung der gerade kompilierten Klassen-template "boost::fusion::result_of::deref<Iterator>". 1> with 1> [ 1> Iterator=enclosing<int>::employee::employee_iterator<enclosing<int>::employee,0> 1> ] 1>c:\users\ulfi\documents\visual studio 2010\projects\test\test\test.cpp(18): error C2893: Funktionsvorlage 'result_of::deref<Iterator>::type boost::fusion::deref(const Iterator &)' konnte nicht spezialisiert werden 1> Mit den folgenden Vorlagenargumenten: 1> 'enclosing<T>::employee::employee_iterator<boost_fusion_uglified_Seq,N>' 1> with 1> [ 1> T=int, 1> boost_fusion_uglified_Seq=enclosing<int>::employee, 1> N=0 1> ] I don't have a clue what is wrong here. Is the error on my side? i just added the template<class T> to the example code of BOOST_FUSION_DEFINE_STRUCT_INLINE. Without, everything is fine. Gretings, Oswin

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