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[Filesystem] Folders with spaces in the name
by Nathan Pierluissi 03 Feb '07

03 Feb '07

Greetings: I am having trouble using the /= operator to open folders with spaces in the name, ex. "My Documents" or "Program Files". Here is an example code: path full_path("c:\"); string Fname="Program Files"; full_path/=Fname; It works for any Fname (folder name) that doesn't have a space. Let me know if you need more information. Thanks in advance. -N. Pierluissi --------------------------------- Want to start your own business? Learn how on Yahoo! Small Business.

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Boost.MultiIndex iterator types
by Jonathan Wang 03 Feb '07

03 Feb '07

I have two multi_index_containers that are identical except for the ordering of the iterators. For example: struct Foo { long x, y; }; typedef boost::multi_index_container<Foo, indexed_by<ordered_non_unique<composite_key<Foo, member<Foo, long, &Foo::x>, member<Foo, long, &Foo::y> > > > > FooAscending; typedef boost::multi_index_container<Foo, indexed_by<ordered_non_unique<composite_key<Foo, member<Foo, long, &Foo::x>, member<Foo, long, &Foo::y> >, composite_key_compare<std::greater<long>, std::greater<long> > > > > FooDescending; The containers are indexed on composite keys of x and y - one in ascending order of y, the other in descending order. I have code that operates on iterators over these containers. Conveniently, the operation is identical, save for the ordering, so I can reuse the interesting code that works on these iterators. However, I am finding that the iterator types for the two containers are identical. Yet if I just define my overload for one of the iterators, everything works as expected. So my question is, is there a way to specify a generic iterator over a multi_index_container such that code on iterators can be reused in this way? It seems from the symbols gcc spits out that the iterator type depends only on the type held and the number of indices in the container (i.e. a container with a unique key on just Foo::x would also have its iterator type collide with FooAscending::iterator and FooDescending::iterator). Thanks, Jonathan

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Serialization of dynamic data
by Anders Sundman 03 Feb '07

03 Feb '07

Hi! About the boost::serialization library, what is the best way to handle dynamic data in classes? Any idéas, suggestions or caveats? I didn't manage to find anything about this in the docs. Consider the following sample class: struct Dyn { Dyn(int s) : data(0), size(s) { data = new char[size]; } ~Dyn() { delete data; } char* data; int size; private: friend class boost::serialization::access; template< class Archive > void serialize( Archive &ar, unsigned int ver ) { // -> ar & data; What to do here? ar & size; } }; What to do with the data pointer? Is there any way to determine (in the serialize function) if a serialization or "de-serialization" is taking place? And have different behaviours - either allocating a new char[x] or copying data to the archive? Is there any way to store dynamic data in an archive? Best regards, Anders Sundman

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some questions regarding ref
by abir basak 03 Feb '07

03 Feb '07

Hi, I want to have a few classes to be stored inside a vector by reference. I thought to use boost::ref for that purpose , instead of storing pointer. However I am facing some problem regarding the operator & . Here is a sample code which gives the problem, struct T2{ int x; T2(int x) :x(x){} }; int main(int argc,char** argv) { std::vector<boost::reference_wrapper<T2> > v; /// vector stores reference, rather than value. T2 t1 = 10; T2 t2 = 15; v.push_back(boost::ref(t1)); /// push ref to t1. v.push_back(boost::ref(t2)); ///push ref to t2. v[0].get().x = 5; ///get by ref & change. /// v[0].x = 5 ; this statement doesn't work! std::cout<<t1.x<<"\n"; ///change is reflected. return 0; } I am not sure why I have to use get for this purpose, while & operator is written for that purpose. Using MSVC 7.1 Even I face problem like this, struct T3{ T2 t2_; T3(int x) : t2_(x){} T2& operator&(){ return t2_; } }; std::vector<T3> v3; v3.push_back(T3(4)); v3.push_back(T3(5)); /// v3[0].x = 6; This doesn't work. (&v3[0]).x = 6; ///This works! Can anyone say a little detail about the problem ? -- Abir Basak, Member IEEE Software Engineer, Read Ink Technologies B. Tech, IIT Kharagpur email: abir(a)abirbasak.com homepage: www.abirbasak.com

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boost::serialization throws random exceptions
by Adrian Grigore 03 Feb '07

03 Feb '07

Hi, I'm experiencing occasional problems with boost::serialization when trying to write then read two simple classes, to a file. I am using boost 1.33.1 Most of the time everything's working fine, but sometimes the serialized data seems to be corrupt and boost::archive throws an exception when I try to load it back into the program. The error occurs about about 1 in 10 times I try this, and seems to depend on the exact values of the variables being saved. Here's a call stack of the thrown application: WxNonogram.exe!_CxxThrowException(void * pExceptionObject=0x00129680, const _s__ThrowInfo * pThrowInfo=0x00ff4954) + 0x50 bytes C++ WxNonogram.exe!boost::throw_exception<boost::archive::archive_exception>(const boost::archive::archive_exception & e={...}) + 0x40 bytes C++ WxNonogram.exe!boost::archive::basic_binary_iprimitive<boost::archive::binary_iarchive,std::basic_istream<char,std::char_traits<char> > >::load_binary(void * address=0x0012d05c, unsigned int count=4) + 0xaf bytes C++ WxNonogram.exe!boost::archive::basic_binary_iprimitive<boost::archive::binary_iarchive,std::basic_istream<char,std::char_traits<char> > >::load<int>(int & t=-858993460) + 0x31 bytes C++ WxNonogram.exe!boost::archive::load_access::load_primitive<boost::archive::binary_iarchive,int>(boost::archive::binary_iarchive & ar={...}, int & t=-858993460) + 0x2d bytes C++ WxNonogram.exe!boost::archive::detail::load_non_pointer_type<boost::archive::binary_iarchive,int>::load_primitive::invoke(boost::archive::binary_iarchive & ar={...}, int & t=-858993460) + 0x2b bytes C++ WxNonogram.exe!boost::archive::detail::load_non_pointer_type<boost::archive::binary_iarchive,int>::invoke(boost::archive::binary_iarchive & ar={...}, int & t=-858993460) + 0x2b bytes C++ WxNonogram.exe!boost::archive::load<boost::archive::binary_iarchive,int>(boost::archive::binary_iarchive & ar={...}, int & t=-858993460) + 0x2b bytes C++ WxNonogram.exe!boost::archive::basic_binary_iarchive<boost::archive::binary_iarchive>::load_override<int>(int & t=-858993460, int __formal=0) + 0x38 bytes C++ WxNonogram.exe!boost::archive::binary_iarchive_impl<boost::archive::binary_iarchive>::load_override<int>(int & t=-858993460, int __formal=0) + 0x31 bytes C++ WxNonogram.exe!boost::archive::detail::interface_iarchive<boost::archive::binary_iarchive>::operator>><int>(int & t=-858993460) + 0x38 bytes C++ WxNonogram.exe!boost::archive::detail::interface_iarchive<boost::archive::binary_iarchive>::operator&<int>(int & t=-858993460) + 0x39 bytes C++ WxNonogram.exe!NoNo::TGameProgress::TProfileState::serialize<boost::archive::binary_iarchive>(boost::archive::binary_iarchive & ar={...}, const unsigned int Version=4) + 0x7a bytes C++ Please help! I'm at a loss on how to proceed. Thanks for your time, Adrian -- Adrian Grigore adrian (AT) lobstersoft.com

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How to build Boost libs with stlportstld versions of stlport??
by Manish Mangal 03 Feb '07

03 Feb '07

Hi How Do I build boost libs with stlportstld dll of stlport when I build the debug versions of the boost libs. I do not want to use the stlportd versions . The command that I use for building boost is: jam "-sTOOLS=vc-8_0-stlport" "-sSTLPORT_VERSION=5.0.0" "-sSTLPORT_5.0.0_PATH=C:\SourceLibrary\STLport" "-sBUILD=debug release <runtime-link>dynamic <threading>multi <stlport-iostream>on <native-wchar_t>on" install Manish Mangal Software Engineer atlas(r) search Partner for Results 206-816-8349 // phone <mailto:t-Matt.Koch@AtlasSolutions.com> Manish.Mangal(a)AtlasSolutions.com www.AtlasSolutions.com <outbind://116-000000001368D4B5F8F6D0488191444C76FD7C9507008921F4CB773B0 545AAED425DEF553BC300003A3500100000DB0C51F64BED3447AA6EC585072C4EC300000 1E3B7A70000/jenniferh/Local%20Settings/Temporary%20Internet%20Files/OLK3 /www.AtlasSolutions.com> // web

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[Filesystem] Folders with spaces in the name
by Nathan Pierluissi 02 Feb '07

02 Feb '07

Greetings: I am having trouble using the /= operator to open folders with spaces in the name, ex. "My Documents" or "Program Files". Here is an example code: path full_path("c:\"); string Fname="Program Files"; full_path/=Fname; It works for any Fname (folder name) that doesn't have a space. Let me know if you need more information. Thanks in advance. -N. Pierluissi --------------------------------- Never Miss an Email Stay connected with Yahoo! Mail on your mobile. Get started!

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boost::interprocess::node_allocator problem (VC8, release build)
by alexmark 02 Feb '07

02 Feb '07

I have a problem with node_allocator. The "repro" code: #include <boost/interprocess/managed_external_buffer.hpp> #include <boost/interprocess/allocators/node_allocator.hpp> #include <boost/interprocess/containers/list.hpp> //////////////// using namespace boost::interprocess; //////////////// enum { A_SHARED_MEMORY_SIZE = 4096 * 50, A_POOL_SIZE = 512, }; //////////////// static char g_static_buffer[A_SHARED_MEMORY_SIZE]; static managed_external_buffer g_sharm (create_only, g_static_buffer, A_SHARED_MEMORY_SIZE); //////////////// typedef node_allocator<int, A_POOL_SIZE, managed_external_buffer::segment_manager> int_allocator_t; typedef list<int, int_allocator_t> IntList; //////////////// struct T { IntList int_list; // T () : int_list (int_allocator_t(g_sharm.get_segment_manager())) {} }; typedef node_allocator<T, A_POOL_SIZE, managed_external_buffer::segment_manager> tis_allocator_t; typedef list<T, tis_allocator_t> TList; //////////////// int main() { TList* p = g_sharm.construct<TList>(anonymous_instance)(tis_allocator_t(g_sharm.get_segment_manager())); try { enum { N = 2 }; // Create objects then delete them for (int n = 0; n < N; n++) { // Create T-type objects for (int i = 0; i < A_POOL_SIZE; i++) { p->push_back(T()); // push new object to the list } p->clear(); // Delete all T objects } } catch (bad_alloc &) { cout << "No memory" << endl; } g_sharm.destroy_ptr(p); return 0; } The problem is the folowing. If N > 1, on _second_ "pass" (n=1) the bad_alloc exception is thrown while pushing new T object to the list. Why? I supposed that on any "pass", except the first one, no new T-type objects are actually created in shared memory. They should be taken from the pool instead. I.e., if there's enough memory on the first "pass", it must be also enough on any other one. The problem is specific for Visual Studio 2005, when producing release build (all options carry their default values). Thanks, Alex.

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How to change a local variable in the if_then algorithm
by Meryl Silverburgh 02 Feb '07

02 Feb '07

Hi, I have a sorted int vector 'orgWidth'. I would like to save the save into a new int vector 'newWidth' if the value of the current element is 10% bigger than the previous one. For example, orgWidth int vector : 300 366 729 769 781 1297 newWidth int vector: 300 366 729 1297 I know how to add the value to the newWidth vector using the if_then with boost. But my question is how can I update the value of the 'previousWidth' as I use for_each() algorithm. int previousWidth = -1; vector<int> orgWidth; for_each(orgWidth.begin(), orgWidth.end(), if_then( (_1 > (previousWidth * 1.1)) , bind (&vector<int>::push_back,boost::ref(newWidth), _1 ))); Thanks for any help.

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installing boost at work
by liamv7 02 Feb '07

02 Feb '07

Hi, I want to use boost at work. What's the best way to make this available to our developers? The options I see: 1. Put the include files and built libs/dlls in version control. I don't see much point to this and binaries take up a lot a space and it's annoying when upgrading. 2. Zip up the include files and dlls and have developers unzip in appropriate location. 3. Let developers access boost over network. To slow. How do you guys manage this? Cheers, Liam.

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Serialization and const
by Anders Sundman 02 Feb '07

02 Feb '07

Hi! I'm having some problems grasping how the serialization library works with respect to const/non-const data. Ex: Consider the following simple class that I would like to serialize: struct Simple { Simple() : member(0) {} Simple(int m) : member(m) {} int member; }; BOOST_CLASS_EXPORT(Simple); BOOST_SERIALIZATION_SPLIT_FREE(Simple); //BOOST_CLASS_TRACKING(Simple, boost::serialization::track_never); namespace boost { namespace serialization { template<class Archive> void save(Archive & ar, const Simple & t, unsigned int version) { ar << t.member; } template<class Archive> void load(Archive & ar, Simple & t, unsigned int version) { ar >> t.member; } } } But when I do the serialization, strange things happen. Ex: const Simple s1(7); //Simple s1(7); boost::archive::text_oarchive oa(ss, f); oa << s1; The non-const alternative above doesn't work unless I do BOOST_CLASS_TRACKING(Simple, boost::serialization::track_never); And, Simple * const s1 = new Simple(7); //Simple * s1 = new Simple(7); boost::archive::text_oarchive oa(ss, f); oa << s1; The non-const alternative above doesn't work even if I do BOOST_CLASS_TRACKING(Simple, boost::serialization::track_never); I'm obviously missing something here, please help me out. Best regards, Anders Sundman

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Re: [Boost-users] installing boost at work
by Nat Goodspeed 02 Feb '07

02 Feb '07

________________________________________ From: boost-users-bounces(a)lists.boost.org [mailto:boost-users-bounces@lists.boost.org] On Behalf Of Sohail Somani Sent: Friday, February 02, 2007 10:40 AM To: boost-users(a)lists.boost.org; boost-users(a)lists.boost.org Subject: Re: [Boost-users] installing boost at work -----Original Message----- From: boost-users-bounces(a)lists.boost.org on behalf of Nat Goodspeed [Nat] we checked the Boost sources & includes into a subtree in our version-control system. we created platform-specific project files and build them along with our own source code. ------------- I do the same thing but I'm curious why you wouldn't just use bjam to build boost? [Nat] That was the first thing we tried, but it failed spectacularly, with voluminous and mysterious output. After a few hours of fruitless twiddling, punctuated by exclamations at the opacity of bjam config files, command line syntax and documentation in general, our frantic combing of the Boost documentation turned up the interesting fact that it also endorses the idea of building Boost libraries with your own toolchain. We grabbed that ball and ran with it, and have never looked back. My colleagues and I have used a lot of computer languages and are not afraid of learning new syntax. But concerning bjam, I'd better stop now lest this message devolve into outright flame. ;-) I like the *idea* of a truly cross-platform build tool. But traffic on this list suggests that, rather than making life easier, bjam is a major stumbling block for a significant number of would-be Boost adopters. To be fair, there's room to hope that the build system v2 is significantly easier to use. None of us here have any desire to investigate, though. And the build-problem messages from other people keep coming in. [Sohail] One thing I do is also check in the binaries per platform/compiler/variant and the build scripts are smart enough to know where to look. The logic behind this was that there is no point rebuilding as 90% of the developers would use the same platform and that the builds would just build our code. [Nat] I've worked with homebrew build systems in which dependency analysis can fetch unmodified executable/library modules even for your own code. It's a good optimization, though it can be a bit finicky to get it right. And you do have to establish the convention that in case of a mysterious crash, do a full rebuild and try again. That said, as I noted earlier, most of the time Boost modules are only built the FIRST time a given developer fetches them from the version-control system. The cost quickly amortizes away.

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Re: [Boost-users] installing boost at work
by Nat Goodspeed 02 Feb '07

02 Feb '07

> -----Original Message----- > From: boost-users-bounces(a)lists.boost.org [mailto:boost-users- > bounces(a)lists.boost.org] On Behalf Of liamv7 > Sent: Friday, February 02, 2007 5:04 AM > To: Boost-users(a)lists.boost.org > Subject: [Boost-users] installing boost at work > > Hi, I want to use boost at work. What's the best way to make this > available to our developers? The options I see: > 1. Put the include files and built libs/dlls in version control. I > don't see much point to this and binaries take up a lot a space and > it's annoying when upgrading. > 2. Zip up the include files and dlls and have developers unzip in > appropriate location. > 3. Let developers access boost over network. To slow. > > How do you guys manage this? [Nat] Probably not what you want to hear, but we checked the Boost sources & includes into a subtree in our version-control system. For the few Boost libraries we use that require building, we created platform-specific project files and build them along with our own source code. Naturally they don't require rebuilding as often as our stuff, but it makes it more uniform for a new developer to get started. This also allows us to use the VCS (Subversion in our case) to manage the problem of merging local patches with new Boost releases.

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[multi_index] no non-const reference even for simple sorted container
by Markus Werle 02 Feb '07

02 Feb '07

> Hi! I tried to use multi_index_container as a drop in replacement for std::map and hoped that I could obtain non-const references to the values therein. Although returning a non-const reference might not be a problem for a multi_index_container with only 1 sorting criterium the lib and the compiler insist on const &. Workarounds beyond modify(...) available? Markus #include <boost/tuple/tuple.hpp> #include <boost/multi_index_container.hpp> #include <boost/multi_index/sequenced_index.hpp> #include <boost/multi_index/key_extractors.hpp> #include <boost/multi_index/ordered_index.hpp> #include <string> namespace bm = ::boost::multi_index; // http://lists.boost.org/boost-users/2005/12/16088.php template<typename Tuple,int N> struct tuple_member_extractor { typedef typename boost::tuples::element<N,Tuple>::type result_type; const result_type& operator()(const Tuple& t) const { return boost::tuples::get<N>(t); } }; typedef boost::tuple<std::string, std::string> element; typedef bm::multi_index_container< element, bm::indexed_by<bm::ordered_unique <tuple_member_extractor<element, 0> > > > multi_t; int main() { multi_t test; test.insert(boost::make_tuple("a", "aa")); // will not compile element & ref = test.find("a"); std::string & s = ref.get<1>(); }

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[bind] how to get a funtor of a function since the function's template argument is a functor
by hongleij＠126.com 02 Feb '07

02 Feb '07

// how to get the functor of function caller below,which could be used in a boost::thread or other condition #include <boost/bind.hpp> #include <iostream> class BufferMoniter { public: void maitain() { std::cout <<" BufferMoniter" << std::endl; } }; class LocalPeer { public: template <class T> void caller(unsigned int interval,T t) { //do something t(); } void fork() { BufferMoniter *pBuffer=new BufferMoniter( ); caller(500,boost::bind(&BufferMoniter::maitain,pBuffer)); //I want a functor of it //boost::thread thrd( ); //insert here //thre.join(); } }; //best wishes

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Re: [Boost-users] Serialization of dynamic data
by Pranckevicius, Tadas 02 Feb '07

02 Feb '07

I have just noticed, shouldn't it be ~Dyn() { delete [] data; } -----Original Message----- From: Anders Sundman [mailto:anders.sundman@optonova.se] Sent: 01 February 2007 14:55 To: boost-users(a)lists.boost.org Subject: [Boost-users] Serialization of dynamic data Hi! About the boost::serialization library, what is the best way to handle dynamic data in classes? Any idéas, suggestions or caveats? I didn't manage to find anything about this in the docs. Consider the following sample class: struct Dyn { Dyn(int s) : data(0), size(s) { data = new char[size]; } ~Dyn() { delete data; } char* data; int size; private: friend class boost::serialization::access; template< class Archive > void serialize( Archive &ar, unsigned int ver ) { // -> ar & data; What to do here? ar & size; } }; What to do with the data pointer? Is there any way to determine (in the serialize function) if a serialization or "de-serialization" is taking place? And have different behaviours - either allocating a new char[x] or copying data to the archive? Is there any way to store dynamic data in an archive? Best regards, Anders Sundman _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users

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[threads] thread_group::create_thread() locks?
by Manuel Jung 02 Feb '07

02 Feb '07

Hi, My program uses a thread group for handling threads. these are joined, when the program ist killed, which should happen not so often, because its used to be a daemon. Most time it works just as expected. but sometimes after running the program for some minutes and after creating a bunch of threads the function thread_group::create_thread() locks. Is this possible? i think it shoulnt lokc, but it does. Im sorry, i cannot show you code cause its closed source and its a liddle bit too big and also works most of the time. I hope a answer to this question will allready help fixing. Thanks for reading. Cheers Manuel Jung

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help with filesystem
by Polder, Matthew J 01 Feb '07

01 Feb '07

Hi, I started using filesystem, regex, and bind today. It's been interesting. I'm using Visual C++ 8.0 on an XP machine that has network filesystems mounted to it, some using letters (H:\, Y:\, etc.), some accessable via two slashes (//linden/temp/, etc). I'd like to peruse these using boost::filesystem. The following works: std::string t = "h:\\temp"; boost::filesystem::path p(t, boost::filesystem::native); but I can't get filesystem to work with the string "h:/temp"; std::string s = p.string(); // s = "h:/temp" bool b = boost::filesystem::portable_posix_name(s); //returns false b = boost::filesystem::windows_name(s); //returns false b = boost::filesystem::portable_name(s); //returns false b = boost::filesystem::portable_directory_name(s); //returns false b = boost::filesystem::portbale_file_name(s); //returns false b = boost::filesystem::native(s); //returns false Also, I'd like to do the following std::string q = "//linden/temp/"; boost::filesystem::path p2(q); Any help is appreciated. thanks, matthew

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help with boost::bind and boost::regex
by Polder, Matthew J 01 Feb '07

01 Feb '07

I am trying to do the following: std::vector< std::string > filenames; //list of filenames retrieved using filesystem boost::regex r(".*txt$"); std::vector< std::string >::const_iterator iter = std::find_if( filenames.begin(), filenames.end(), boost::bind(boost::regex_match, _1, r) ); //Doesn't compile. I'm trying to find strings that match (or don't match) a particular regular expression. Help in properly using boost::bind and negating it would be helpful. thanks, matthew

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Build only static library with -fPIC option.
by Bo Peng 01 Feb '07

01 Feb '07

Dear list, I am building boost cvs. For my specific application, I need to build only static libraries with -fPIC option. I tried command > bjam -j4 --prefix=/usr "-sBUILD=release <runtime-link>static <cxxflags>-fPIC" --with-serialization --with-iostreams install But I still get .a and .so libraries under /usr/lib. I used -n option (an advise I get from one of my previous posts) and the building commands are like: "g++" -ftemplate-depth-128 -O3 -finline-functions -Wno-inline -Wall -DBOOST_ALL_NO_LIB=1 -DNDEBUG -I"." -c -o "bin.v2/libs/serialization/build/gcc-3.4.6/release/link-static/binary_wiarchive.o" "libs/serialization/src/binary_wiarchive.cpp" so no -fPIC is passed. I tried bjam -h, but get even more confused because I am told.. -n Don't actually execute the updating actions. I guess cvs/bjam handles these options totally differently than boost 1.33.1, but how can I get the latest information? Many thanks in advance. Bo

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[bind] how to get the type after bind
by hongleij＠126.com 01 Feb '07

01 Feb '07

//my question is how to write the type ??? below to make it run . #include <boost/bind.hpp> #include <iostream> using boost::bind; void print() { std::cout <<" print" << std::endl; } template <class T> void func(T t) { std::cout <<"func1(T t) : " ; t(); } int main() { func(bind(&print)); //ok bind ( &func<???>, bind(&print) ) ; //don't know how to write it }

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Re: [Boost-users] [bind] how to get the type after bind
by Nat Goodspeed 01 Feb '07

01 Feb '07

________________________________________ From: boost-users-bounces(a)lists.boost.org [mailto:boost-users-bounces@lists.boost.org] On Behalf Of hongleij(a)126.com Sent: Thursday, February 01, 2007 9:00 AM To: boost-users(a)lists.bo... Subject: [Boost-users] [bind] how to get the type after bind //my question is how to write the type ??? below to make it run . #include <boost/bind.hpp> #include <iostream> using boost::bind; void print() { std::cout <<" print" << std::endl; } template <class T> void func(T t) { std::cout <<"func1(T t) : " ; t(); } int main() { func(bind(&print)); //ok bind ( &func<???>, bind(&print) ) ; //don't know how to write it } [Nat] This doesn't directly answer your question; the type produced by bind() is obscure. But would the following suit your need? bind ( &func< boost::function<void ()> >, bind(&print) ) ;

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[boost-thread] why not writ e "sleep" in a better
by hongleij＠126.com 01 Feb '07

01 Feb '07

hi: it really a trouble thing for me to use boost::thread::sleep() : boost::xtime helloworldtime; boost::xtime_get(&helloworldtime, boost::TIME_UTC); helloworldtime.sec += 6; boost::thread::sleep(helloworldtime); i think "boost::thread::sleep(1500) //millisecond " may easy my programming;if have such interface; now i use : void thread_sleep(unsigned int interval) //millisecond { boost::xtime xt; boost::xtime_get(&xt, boost::TIME_UTC); int sec=interval/1000; int msec=interval-1000*sec; xt.nsec += 1000*1000*msec; xt.sec+= sec; boost::thread::sleep(xt); } best wishes;-)

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mapped_file_sink
by Alf Kraus 01 Feb '07

01 Feb '07

does anyone have an example of using *mapped_file_sink *to create and write into a memory mapped file?

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mapped_file_sink
by Alf Kraus 01 Feb '07

01 Feb '07

I'm trying to create memory mapped files using mapped_file_sink: mapped_file_params mfParams( fileName ); mfParams.new_file_size = filesize; mapped_file_sink mfSink( mfParams ); trying to use any of its funtions like: const char *ptStart = mfSink.data(); the compiler tells me that I have no access to them for they are private members since inherited from mapped_file I know thats a piece of cake but just cant solve it. Cheers Alf

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problem with boost/iterator/zip_iterator.hpp
by Tim Axelrod 01 Feb '07

01 Feb '07

Hello, If more than one source file includes boost/iterator/zip_iterator.hpp, the loader complains about a multiply defined function: tsa@mops2.lsstcorp.org:~/VW/TSA> g++ -o nothing nothingMain.cc nothing.cc /tmp/ccT5Bn0N.o: In function `boost::detail::tuple_impl_specific::tuple_equal(boost::tuples::null_type, boost::tuples::null_type)': nothing.cc:(.text+0x0): multiple definition of `boost::detail::tuple_impl_specific::tuple_equal(boost::tuples::null_type, boost::tuples::null_type)' /tmp/ccH8Z9eR.o:nothingMain.cc:(.text+0x0): first defined here collect2: ld returned 1 exit status I'm using boost_1_33_1. The source files are attached. Regards, Tim Axelrod

2 1

shmem map tutorial
by Jan Stetka 31 Jan '07

31 Jan '07

I've put together a tutorial on how to use interprocess map. Its at http://myweb.tiscali.co.uk/janstetka/interprocess_map.html Perhaps there could be a link from the interprocesses documentation if it goes down well. Thanks PS:I tried to use the wiki but the syntax is a bit too difficult for me especially formating code so I've put it on my own site for now.

1 0

matrix inversion
by Umut Tabak 31 Jan '07

31 Jan '07

hi list, I have been experimenting to find the incerse aof a matrix with ublas but there is a problem: I have been looking at the code on http://www.crystalclearsoftware.com/cgi-bin/boost_wiki/wiki.pl?LU_Matrix_In… But there is sth wrong with that code because assign function template does not take a ublas::matrix<> as a direct parameter, it should ne converted to a matrix_expression but how may I do that. I did the inversion by using the assignment operator but wondered how it could be done thorough assign function template. The code on the viki works if you change the line with the assign to inverse=ublas::identity_matrix<T>(A.size1()); Maybe it can be of help. My best,

1 0

Re: [Boost-users] problems with serialization library
by mauro gargano 31 Jan '07

31 Jan '07

thanks a lot Mark Wyszomierski!

1 0

Question about using Boost::for_each function to set a local variable if a condition is met
by Meryl Silverburgh 31 Jan '07

31 Jan '07

Hi, I am trying to Boost::for_each function to set a local variable if all elements in this is DEFAULT type. Here is my code, but I don't know how to implement the last part of the if_then call. boolean rtnValue = false; for_each(mylist.begin(), mylist.end(), if_then( bind(&ListItem::getType, _1) == DEFAULT, set the local value to true if true if all of them are DEFAULT type )); if you can give me some pointers, I will be appreciated. Thank you.

3 3

Open file name starting with "." in boost::filesystem
by Peng Yu 31 Jan '07

31 Jan '07

Hi, The following program gives some error. Can somebody let me know if it is possible to open filenames starting with "."? Thanks, Peng int main() { boost::filesystem::ofstream file(".abc"); } $ ./main-g.exe terminate called after throwing an instance of 'boost::filesystem::filesystem_error' what(): boost::filesystem::path: invalid name ".abc" in path: ".abc" Aborted

2 1

[boost.threads] condition api question
by Frank Mori Hess 30 Jan '07

30 Jan '07

I'm curious why the boost::condition class requires a seperate mutex object to be created, and a corresponding scoped lock argument passed to the wait functions. Wouldn't it be easier to just keep a mutex inside the condition object and automatically lock it at the beginning of the wait functions? What am I missing here? -- Frank

1 1

[lexical_cast] converting "true" to bool fails - why?
by Markus Werle 30 Jan '07

30 Jan '07

Hi! The following code snippet prints "failure!" during execution: #include <boost/lexical_cast.hpp> #include <iostream> int main() { try { bool test = boost::lexical_cast<bool>("true"); } catch (boost::bad_lexical_cast const &) { std::cerr << "failure!\n"; } } IIRC there was some way to achieve a conversion using the correct locale and stringstreams. Is there a way to obtain a successful conversion with lexical_cast, too? Markus

1 0

[BGL] Problems with remove_vertex
by Adrian Boeing 30 Jan '07

30 Jan '07

Hi, I have a an adjacency_list graph, which I've been using fine. I would like to remove a vertex from the graph, and I do so by calling: clear_vertex then remove_vertex If I then try a call to: adjacent_vertices on a vertex that used to have the removed vertex as a parent, my program then crashes on the line 1481 "boost::tie(first, last) = out_edges(u, g);" of adjacency_list.hpp I'm using MSVC8.0 Any advice on what might be going wrong would be much appreciated. Thanks, -Adrian

4 5

[BGL] vertices creates new objects
by George Sakkis 30 Jan '07

30 Jan '07

I've just started playing with the python bindings of BGL and I'm puzzled from the following: >>> from boost.graph import Graph >>> g = Graph() >>> v = g.add_vertex() >>> g.vertices.next() == v True >>> g.vertices.next() is v False It seems that the vertices iterator creates new vertex objects every time instead of iterating over the existing ones. This essentially prevents, among other things, storing vertices as keys in a dictionary since the hashes of the stored and the new vertex differ although they compare equal. Is this really what's happening, and if so, why ? Thanks, George

2 3

what is the proper path setup?
by Ferng, Andrew D 30 Jan '07

30 Jan '07

I'm installing boost 1.33.1 on AIX 5.3 My home directory is /acct/a/adf After 'make install', it is in /DIR_Boost so I have the following: /acct/a/adf/DIR_Boost/include /acct/a/adf/DIR_Boost/lib All the hpp are in: /acct/a/adf/DIR_Boost/include/boost-1_33_1/boost Now I'm trying a sample program in /acct/a/adf/BOOST When I compile with 'g++ c.cpp' I get: > g++ c.cpp c.cpp:10:28: error: boost/config.hpp: No such file or directory c.cpp:15:42: error: boost/graph/adjacency_list.hpp: No such file or directory c.cpp:16:48: error: boost/graph/connected_components.hpp: No such file or directory c.cpp: In function 'int main(int, char**)': c.cpp:41: error: 'boost' is not a namespace-name c.cpp:41: error: expected namespace-name before ';' token c.cpp:43: error: expected initializer before '<' token c.cpp:45: error: 'Graph' was not declared in this scope c.cpp:45: error: expected `;' before 'G' c.cpp:46: error: 'G' was not declared in this scope c.cpp:46: error: 'add_edge' was not declared in this scope c.cpp:51: error: 'num_vertices' was not declared in this scope c.cpp:52: error: 'connected_components' was not declared in this scope The headers are: #include <boost/config.hpp> #include <iostream> #include <vector> #include <algorithm> #include <utility> #include <boost/graph/adjacency_list.hpp> #include <boost/graph/connected_components.hpp> In .cshrc, I've already got: set path=(~/DIR_Boost/include/boost-1_33_1 ~/gcc/usr/local/bin $path) Did I build boost incorrectly or am I just missing some path setup? Thanks!

1 1

Class template normal_distribution. What is the actually mapping function?
by Jeanette Auer 30 Jan '07

30 Jan '07

Does anyone know what is the actual mapping function used by the <boost/random/normal_distribution.hpp> to map uniform random into the normal distribution? While I suspect it is the Marsaglia's ziggurat algorithm I need to know for certain and I can not find the details on the BOOST site. Thanks in advance for any help. Jeanette Auer Associate Lecture Dept. Comp. Sci. & Comp. Eng La Trobe University Victoria 3086

2 1

[boost.threads] condition documentation bug
by Frank Mori Hess 29 Jan '07

29 Jan '07

The documentation for condition::timed_wait has an error at http://www.boost.org/doc/html/condition.html The prototype for the form of timed_wait that takes a predicate leaves off the const boost::xtime& xt parameter. -- Frank

2 1

[BGL] randomize_property() bug?
by Dmitry 29 Jan '07

29 Jan '07

Line 193 should be void randomize_property(G& g, RandomGenerator& rg, Property) instead of void randomize_property(G& g, RandomGenerator& rg) ?? Regards, --Dmitry

2 1

quick serialization question
by Mark Wyszomierski 29 Jan '07

29 Jan '07

Hi, The serialization examples use const instances of classes like: const CMyClass test; outstream_var << test; is there anyway to remove the const keyword and still have it work? I rarely construct const classes, so I had to make an ugly wrapper which copies my objects into a temporary const instance when it's time to serialize. Thanks, Mark

2 2

BGL Question: embedded graph with faces
by Andreas Fabri 29 Jan '07

29 Jan '07

Hello, Does anybody work on extending the graph concept hierarchy of the BGL in order to deal with graphs that are embedded, that is the edges which are adjacent to a vertex are ordered consistently, and if you go from an edge to the successor edge at a vertex you walk along a face. Maybe even another graph concept where the faces can have holes. I ask because we already write graph traits specializations for the polyhedral surface of CGAL, which uses a halfedge data structure, and I don't want to reinvent the wheel in case all the terminology is already existing, and I only haven't found it yet. Thanks in advance, andreas

2 1

problems with serialization library
by mauro gargano 29 Jan '07

29 Jan '07

Hi everybody, I'm having deep troubles with the serialization library. I need to serialize a class (called VisualisationObject3D), but every time I try to serialize it I get a static compile error boost::STATIC_ASSERTION_FAILURE<x> referring to the line: oa << _obj (below you find the error stack and the source code). Since the error has to do with the tracking I tried disabling the trackin also, but without success. CAN SOMEBODY HELP ME? thanks in advance, Mauro. ------------------------ SOURCE CODE ------------------- class VisualisationPoint3D; class VisualisationObject3D { public: VisualisationObject3D(); ~VisualisationObject3D(){} std::vector<VisualisationPoint3D> m_vPoints; } void send_3D_object(VisualisationObject3D* _p){ tcpserialize::serialize_with_boost_to_socket<VisualisationObject3D>(_p,g_socket); } template<class T> bool serialize_with_boost_to_socket(const T* _obj, StreamSocket* send_socket){ std::strstream ss; { boost::archive::text_oarchive oa(ss); /*ERROR*/ oa << _obj; } char* _serialized_data=ss.rdbuf()->str(); size_t _serialized_data_size = ss.rdbuf()->pcount(); ...... return true; }; BOOST_CLASS_TRACKING(VisualisationPoint3D, boost::serialization::track_never) BOOST_CLASS_TRACKING(VisualisationObject3D, boost::serialization::track_never) namespace boost { namespace serialization { template<class Archive> void serialize(Archive & ar, VisualisationPoint3D & o, const unsigned int /* version */) { ar & ....; } template<class Archive> void serialize(Archive & ar, VisualisationObject3D & o, const unsigned int /* file_version */){ ar & .....; } } // namespace serialization } // namespace boost ------------------------ ERROR ------------- the error stack is here attached: d:\boost_1_33_1\boost\archive\detail\oserializer.hpp(567) : error C2027: Verwendung des undefinierten Typs "boost::STATIC_ASSERTION_FAILURE<x>" with [ x=false ] d:\boost_1_33_1\boost\archive\detail\oserializer.hpp(567): Siehe Verweis auf Instanziierung der kompilierten Klassenvorlage 'boost::STATIC_ASSERTION_FAILURE<x>' with [ x=false ] d:\boost_1_33_1\boost\archive\basic_text_oarchive.hpp(78): Siehe Verweis auf Instanziierung der kompilierten Funktionsvorlage 'void boost::archive::save<Archive,T>(Archive &,T & )' with [ Archive=boost::archive::text_oarchive, T=const VisualisationObject3D * ] d:\boost_1_33_1\boost\archive\detail\interface_oarchive.hpp(78): Siehe Verweis auf Instanziierung der kompilierten Funktionsvorlage 'void boost::archive::basic_text_oarchive<Archive>::save_override<T>(T & ,int)' with [ Archive=boost::archive::text_oarchive, T=const VisualisationObject3D * ] h:\SHARED\UNDER_REPOSITORY_CONTROL2\TEST_PROGRAMS\NetworkManagerDll\network-tools\tcpserialize.h(122): Siehe Verweis auf Instanziierung der kompilierten Funktionsvorlage 'Archive &boost::archive::detail::interface_oarchive<Archive>::operator <<<const T*>(const VisualisationObject3D & )' with [ Archive=boost::archive::text_oarchive, T=VisualisationObject3D ] h:\SHARED\UNDER_REPOSITORY_CONTROL2\TEST_PROGRAMS\NetworkManagerDll\NetworkManager.cpp(46): Siehe Verweis auf Instanziierung der kompilierten Funktionsvorlage 'bool tcpserialize::serialize_with_boost_to_socket<VisualisationObject3D>(const T *,tcpserialize::StreamSocket *)' with [ T=VisualisationObject3D ]

2 1

[interprocess] boost::interprocess::deque::clear is private?!
by Lars Hagström 29 Jan '07

29 Jan '07

In the boost CVS the clear()-method of boost::interprocess::deque is private. Is this by design or mistake? If it is by design, could anyone enlighten me as to why? Lars

2 2

[regex] problem with pattern match in 1.33.0
by Richard Hadsell 29 Jan '07

29 Jan '07

I am having a problem with a regex_match in Boost 1.33.0. Perhaps I am missing something; perhaps it is a bug that has been fixed. The pattern "[+-]?(\\d+(\\.\\d*)?|\\.\\d+)([Ee][+-]?\\d+)?" should match only floating-point numbers that can be read by sscanf. (Extra escape characters are for C++, of course.) Yet regex_match returns true for "3.6.5". I guessed that the problem might be in the '(...)?' expression just before the alternative operator '|', so I tried this: "[+-]?(\\d+|\\d+\\.\\d*|\\.\\d+)([Ee][+-]?\\d+)?". With this pattern regex_match returns false for "3.6.5". I am using it, but I consider it a workaround. Can someone explain what I have missed or whether this is a bug? -- Dick Hadsell 914-259-6320 Fax: 914-259-6499 Reply-to: hadsell(a)blueskystudios.com Blue Sky Studios http://www.blueskystudios.com 44 South Broadway, White Plains, NY 10601

2 3

[Review] Review of the Accumulator library begins today, Jan. 29
by John Phillips 29 Jan '07

29 Jan '07

The formal review of the Boost.Accumulators library, submitted by Eric Neibler begins today and ends on Wednesday, February 7. The library is available from http://boost-consulting.com/vault/index.php?directory=Math%20-%20Numerics From the documentation: Boost.Accumulators is both a library for incremental statistical computation as well as an extensible framework for incremental calculation in general. The library deals primarily with the concept of an accumulator, which is a primitive computational entity that accepts data one sample at a time and maintains some internal state. These accumulators may offload some of their computations on other accumulators, on which they depend. Accumulators are grouped within an accumulator set. Boost.Accumulators resolves the inter-dependencies between accumulators in a set and ensures that accumulators are processed in the proper order. Your comments may be brief or lengthy. If you identify problems along the way, please note if they are minor, serious, or showstoppers. Here are some questions you might want to answer in your review: • What is your evaluation of the design? • What is your evaluation of the implementation? • What is your evaluation of the documentation? • What is your evaluation of the potential usefulness of the library? • Did you try to use the library? With what compiler? Did you have any problems? • How much effort did you put into your evaluation? A glance? A quick reading? In-depth study? • Are you knowledgeable about the problem domain? And finally, every review should answer this question: • Do you think the library should be accepted as a Boost library? Be sure to say this explicitly so that your other comments don't obscure your overall opinion. All interested parties are encouraged to submit a review. These can be sent to the developer list, the user list, or if you don't want to share your review with the general public it can be sent directly to me. Thanks to all for the work you will do on this review. John Phillips Review Manager

1 0

[program_options] Allowing Unknown Options
by Imre Palik 29 Jan '07

29 Jan '07

Hi, I try to use the same configuration file with several programs. For this I hope, I can somehow allow unknown options for config files. The method described in the documentation only works for the command line, and skimming through the code didn't help either. Is there any other way to do it, than patching the common_config_file_iterator? If no, then what are the submission rules for patches? Thx ImRe

1 0

Re: [Boost-users] Euclidean MST using CGAL and Boost
by miles mccoo 29 Jan '07

29 Jan '07

> > > Hi, > > > I patched together code for Euclidean MST based on CGAL and Boost. I > posted in on Wikipedia because I couldn't think of a more appropriate place. > > > http://en.wikipedia.org/wiki/Sample_Code_for_Euclidean_MST_using_Boost_and_… > > > > I would love to receive feedback on it. I hope someone finds it's useful. > > > > Miles >

2 1

Work-around for linker removed BOOST_AUTO_TEST_CASE code
by daniel.hawson＠virgin.net 29 Jan '07

29 Jan '07

I'd encountered a problem with a particular way I'd set up a test application where some BOOST_AUTO_TEST_CASE functions would be executed while others wouldn't. I suspect this may be Visual Studio (2005) specific. I've got a work-around, which I thought might help others in the same situation. The scenario is this - Main test application: testapp.cpp - #define BOOST_AUTO_TEST_MAIN "TestApp for some Lib" #include <boost/test/auto_unit_test.hpp> BOOST_AUTO_TEST_CASE(IGetExecutedByTestFramework) { BOOST_CHECK(false); } External library, containing: somemodule_tests.cpp - #include "somemodule.h" #include <boost/test/auto_unit_test.hpp> //Test functionality provided by somemodule.h //... BOOST_AUTO_TEST_CASE(IDontGetExecuted) { BOOST_CHECK(false); } My Visual Studio solution contains two projects - - mylibtestapp: A console executable to run all test cases in mylib Contains only testapp.cpp - mylib: A statically linked lib containing a bunch of .cpp/.h files and, so far, just one ..._tests.cpp file. The solution is set up so that mylibtestapp depends on mylib. It also explicitly links with the boost 'unit_test_framework.lib'. It compiles and links fine. When running, only the 'IGetExecutedByTestFramework' gets executed. I manually expanded the BOOST_AUTO_TEST_CASE macro for 'IDontGetExecuted' and the debugger wouldn't step into any of the test registrar object constructor code, so I assume the linker decided to strip out the code for some reason. As soon as I added the following to somemodule_tests.cpp - int g_fiddle; and change testapp.cpp to 'extern int g_fiddle;' and manually insert the 'init_unit_test_suite(int argc, char* argv[])' with some trivial use of 'g_fiddle' (using it in a printf), then both test cases get executed. After poking around with the linker options little further, I've found that all unit tests will run as originally intended, without having to use any extern frigs, so long as the mylibtestapp's 'Configuration Properties'>Linker>General>'Use Library Dependency Inputs' is set to 'Yes'. The difference being that the linker command-line now contains mylib.lib instead of the individual .o files of mylib. Weird. -- Checked by AVG Free Edition. Version: 7.5.432 / Virus Database: 268.17.12/655 - Release Date: 28/01/2007 13:12

1 0

std::string to std::wstring
by John Christopher 29 Jan '07

29 Jan '07

Hello, Does Boost contain facilities to convert std::string into std::wstring and the other way around? Thanks in advance

5 7

[mpl] Problem comparing iterators
by Küppers, Ben 29 Jan '07

29 Jan '07

Gents, For illustration purposes I created the following code that iterates through a sequence and accumulates the distances between the current iterator and the beginning of the sequence. Somehow this code works for normal ranges (range1 and range2) but fails to compile for joint_view range3 (80-plus errors). Changing the call to distance to compare between begin and end or between _2 and _2 (self) works. I am at a loss here. Can someone point out what I am doing wrong? Thanks Ben #include <iostream> #include <boost/mpl/arithmetic.hpp> #include <boost/mpl/begin.hpp> #include <boost/mpl/distance.hpp> #include <boost/mpl/for_each.hpp> #include <boost/mpl/iter_fold.hpp> #include <boost/mpl/joint_view.hpp> #include <boost/mpl/plus.hpp> #include <boost/mpl/push_back.hpp> #include <boost/mpl/range_c.hpp> #include <boost/mpl/vector_c.hpp> namespace mpl = boost::mpl; template< class _Sequence > struct distances { typedef typename mpl::iter_fold< _Sequence, mpl::long_< 0 >, mpl::plus< mpl::_1, mpl::distance< typename mpl::begin< _Sequence >::type, // typename mpl::end< _Sequence >::type // mpl::_2, mpl::_2 > > >::type type; }; int main( int argc, char* argv[] ) { typedef mpl::range_c< char, 'a', 'd' >::type range1; typedef mpl::range_c< char, 'm', 'q' >::type range2; typedef mpl::joint_view< range1, range2 >::type range3; typedef distances< range3 >::type type1; std::cout << type1(); std::cout << std::endl; return 0; } This e-mail and any attachment is for authorised use by the intended recipient(s) only. It may contain proprietary material, confidential information and/or be subject to legal privilege. It should not be copied, disclosed to, retained or used by, any other party. If you are not an intended recipient then please promptly delete this e-mail and any attachment and all copies and inform the sender. Thank you.

2 1

'is_pointer_like' or 'is_smart_pointer' or similar, again
by Gottlob Frege 29 Jan '07

29 Jan '07

A while back there was discussion of detecting smart pointers. The discussion started with Ovanes Markarian Date: Thu, 22 Jun 2006 19:19:07 +0200 (CEST) From: "Ovanes Markarian" <om_boost(a)keywallet.com> Subject: [Boost-users] inspecting templates and boost::is_pointer To: boost-users(a)lists.boost.org Message-ID: <41230.194.138.18.132.115099674 > > 7.squirrel(a)www.keywallet.com> > Content-Type: text/plain;charset=iso-8859-1 > > Hello all, > > I am trying to specialize boost::is_pointer so, that it can determine if a > type is a pointer > wrapper (shared_ptr, auto_ptr, weak_ptr). ..... And, first off, yes, we now know that expanding is_pointer would be bad. So, instead we want 'is_pointer_like' or something like that. There were suggestions regarding detecting operator->() and/or unary operator *(). What ever came of this? I am asking, of course, because I could really use an 'is_pointer_like<>' or 'is_smart_ptr' right now. And if it is still unsolved, I've got 2 more suggestions: detecting that boost::get_pointer() (for boost::bind) has been defined, and/or just looking for some common internals of the smart_ptrs (hack!) - or adding some common internal typedef/value - ie T::is_smart_pointer. Thanks, Tony

4 6

[Boost-build]/[bjam] Problem compiling CVS bjam from sources
by D Garvey 29 Jan '07

29 Jan '07

As far as I'm aware I'm using pretty much a default ubuntu installation with gcc 4.1.2. After compiling bjam from sources, using these<http://boost.org/boost-build2/doc/html/jam/building.html>instructions, and running the tests, I get the following failures: root@---------:/usr/local/src/boost/tools/jam/test# sh test.sh > --- Testing SHELL builtin... > --- Testing W32_GETREGNAMES builtin... > --- Testing var expansion... > --- Testing var on target semantics... > --- Testing var expansion... > var_expand.jam:14: error: [FAILED] (==) '' > var_expand.jam:17: error: [FAILED] (==) '' > --- Complete: PASSED(21) *FAILED(2)* > The output from the compilation is below (it seems to work, even with the lists of warnings): root@hallah:/usr/local/src/boost/tools/jam# cd src | sh ./build_dist.sh > ../../../Jamfile.v2:335: in load-aux > rule path.glob-tree unknown in module Jamfile</usr/local/src/boost>. > /usr/share/boost-build/build/project.jam:318: in load-jamfile > /usr/share/boost-build/build/project.jam:68: in load > /usr/share/boost-build/build/project.jam:120: in load-parent > /usr/share/boost-build/build/project.jam:447: in initialize > /usr/share/boost-build/build/project.jam:301: in load-jamfile > /usr/share/boost-build/build/project.jam:68: in load > /usr/share/boost-build/build/project.jam:120: in load-parent > /usr/share/boost-build/build/project.jam:447: in initialize > /usr/share/boost-build/build/project.jam:301: in load-jamfile > /usr/share/boost-build/build/project.jam:68: in load > /usr/share/boost-build/build/project.jam:170: in project.find > /usr/share/boost-build/build-system.jam:148: in load > /usr/share/boost-build/kernel/modules.jam:261: in import > /usr/share/boost-build/kernel/bootstrap.jam:132: in boost-build > /usr/local/src/boost/boost-build.jam:9: in module scope > cp: cannot stat `html/*': No such file or directory > ### > ### Using 'gcc' toolset. > ### > rm -rf bootstrap > mkdir bootstrap > gcc -o bootstrap/jam0 command.c compile.c debug.c execunix.c expand.c > fileunix.c glob.c hash.c hdrmacro.c headers.c jam.c jambase.c jamgram.c > lists.c make.c make1.c newstr.c option.c parse.c pathunix.c pathvms.c > regexp.c rules.c scan.c search.c subst.c timestamp.c variable.c modules.c > strings.c filesys.c builtins.c pwd.c class.c native.c w32_getreg.c > modules/set.c modules/path.c modules/regex.c modules/property-set.cmodules/sequence.c modules/order.c > execnt.c filent.c > compile.c: In function 'compile_set': > compile.c:1151: warning: passing argument 2 of 'assign_var_mode' from > incompatible pointer type > compile.c: In function 'compile_settings': > compile.c:1244: warning: passing argument 2 of 'assign_var_mode' from > incompatible pointer type > ./bootstrap/jam0 -f build.jam --toolset=gcc --toolset-root= clean > ...found 1 target... > ...updating 1 target... > ...updated 1 target... > ./bootstrap/jam0 -f build.jam --toolset=gcc --toolset-root= > ...found 46 targets... > ...updating 2 targets... > [MKDIR] bin.linuxx86 > [COMPILE] bin.linuxx86/bjam > compile.c: In function 'compile_set': > compile.c:1151: warning: passing argument 2 of 'assign_var_mode' from > incompatible pointer type > compile.c: In function 'compile_settings': > compile.c:1244: warning: passing argument 2 of 'assign_var_mode' from > incompatible pointer type > hash.c: In function 'hash_search': > hash.c:126: warning: pointer targets in passing argument 1 of 'strlen' > differ in signedness > hash.c:126: warning: pointer targets in passing argument 2 of > '__builtin_strcmp' differ in signedness > hash.c:126: warning: pointer targets in passing argument 2 of > '__builtin_strcmp' differ in signedness > hash.c:126: warning: pointer targets in passing argument 1 of 'strlen' > differ in signedness > hash.c:126: warning: pointer targets in passing argument 2 of > '__builtin_strcmp' differ in signedness > hash.c:126: warning: pointer targets in passing argument 2 of > '__builtin_strcmp' differ in signedness > ...updated 2 targets... > Note that the first 10 or so lines of the output above keep coming up when I'm trying to build other boost libraries. What am I doing wrong? --- Darren Garvey

2 2

BoostCon 2007 Program Committee progress report
by Beman Dawes 28 Jan '07

28 Jan '07

We've got interesting proposals from experienced presenters, have accepted a bunch, and have started to put together a tentative schedule for the week. We should finish accepting proposals in the next week or so and be able to go public with the schedule real soon after that. The people we have sessions proposals from are listed below. If you sent in a proposal and are not on the list, please contact me right away! Dave Abrahams Beman Dawes Jeff Garland Doug Gregor Mat Marcus Scott Meyers Eric Niebler Kevlin Henney Howard Hinnant Harmut Kaiser / Joel de Guzman Sean Parent Gennadiy Rozental Timothy Shead Jeremy Siek Matthias Troyer The conference dates (May 14-16) are firm, and other arrangements are moving forward. See http://www.boost.org/more/BoostCon07.html Thanks to Dave Abrahams and Boost-Consulting for providing the wiki we are using to coordinate conference planning. It is invaluable. --Beman Dawes, BoostCon 2007 Program Committee chair

4 3

socket streams?
by grahamspam＠earthlink.net 28 Jan '07

28 Jan '07

Hello, I did not find a streams implementation for sockets. Is such being developed? Thanks, Jeff

6 6

Re: [Boost-users] problem with boost::strong_components
by Dmitry 28 Jan '07

28 Jan '07

Hi, Tamas Why you don't try this, seems should work: graph_t cityg (bigedges.begin (), bigedges.end (), bigweights.begin (), dim); int num = strong_components(cityg, &component[0]); you use std::vector as vertex storage, right? Regards, Dmitry > Hello, > I'm trying to use the boost library's strong_components function to > partition a graph to connected sub-partitions, and ran into a problem. > std::vector<int> other; > // fill up the vector with the vertices by pushing back each one. The number > of vertices is about 170k and the biggest vertex index is about 260k. > // .. > // bigedges and bigweights have the edges and the weights, dim is the total > number of vertices - all these are checked and proper. > > graph_t cityg (bigedges.begin (), bigedges.end (), bigweights.begin (), > dim); > std::vector<int> component(num_vertices(cityg)); > int num = strong_components(cityg, &component[0], boost::vertex_index_map > (&other[0])); > > Tamas >

1 0

[regex] memory exhausted
by Kyle Alons 27 Jan '07

27 Jan '07

The attached sample works properly in boost v1.30.2 but fails with a 'Memory exhausted' exception in v1.31 through v1.33.1. Is this a bug, and/or do you have any ideas on rephrasing the expression to work in boost 1.33.1? Thanks. --------------------- Kyle Alons http://www.kinook.com begin 666 regex.zip M4$L#!!0````(`!!2+38?'+8'N0$``&<#```(````=&5S="YC<'"54LMNVS 0 M/,N _V'AJ UI"VI3]P'(;@]]H7?W%@8%(Z\E`A(E4.M81I-_[Y*6W3A%"_0@ M:K'#F1TNYL+8O-JN$9:W3=/1"X<%]FG9MA_&HXL3UG?DC"W.>AONH:ZY-QX9 M2U!K8X4OM"OR!/)2NZFO[ZYOY'CT<SR*R.WY]%74T3K+#J)@; *5L;@X`6;0 MAHV8Y)E2QK9;2JFGB0R7=J6I$$2!Y'EB<^!+"1Z,C(79^]"!&5PJ>[D`[_%\ M*/:M6Y$3$Z'4;J:4D"*=WBMEIW*U[PAKI=+/FO3P6R%!N"G%=2)OTJE4:L[E M@R\_8F&L4E=*O?H;]W#[*?&+73-M>-1C=P[;*KB+K^)!,TB=].)Y_/H;5BVZ M]%-C[]#15]?4C.)W4R,_)YXST.ZY4HI'ROA-</D/O;?_I_>.S<<'[]Y]2$^6 MA?B$Y8IAPPG\AFYUAUEF&U?K"N[_`$S./[F(GFZCV9)XK/^C1E>@\+GQ0Y+C MNN313" WIQ!Y?L@1%^=!\A LEWZ"#TGTP%^N*2]!Y(WM"((2]CFV9!K['% > M$]RR->)\/NLF;"/=E9I$,.!%^'1(6V?A)7>X\0M02P,$% ````@`%W4L-B4* M`<.C" ``.6\```D```!I;G!U="YT>'3M7%]OVS80?UZ!?@<B3PZ6REVQ84#; M#$B<K<O0=5F<K ."/- 2:W.518VDDGI#/]D>]I'V%7;47\JF:-FUY#J6'A*% M.I)WO[O[\41)^>^??_O])QL]'C_J]]%+'$GV9$P"PK$DWG=QHSJN)E0@EWD$ MW6.!<@$TFB&,)&.^DXM>1H&D4X)^(UQ0%CQ_YCQUOGGZ[;-OG:^?*:%<<##! 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Re: [Boost-users] 2. TRY boost::thread - problem with worker as an inner class of a queue
by Lars Kunert 27 Jan '07

27 Jan '07

Sorry, I have have shortened the code to some degree - taking the joins out. But the problem really seams to be in the constructor: > QueueError( ST max_queue_size =1000 ) > : max_queue__size__( max_queue_size ) > , thread_( Worker( this )) > {}; In all examples given in the in boost::threads global or static member functions are called - is that neccessary??? Thank, Lars

2 1

2. TRY boost::thread - problem with worker as an inner class of a queue
by Lars Kunert 27 Jan '07

27 Jan '07

Dear Moderator! Yesterday I posted a mail to boost-users. I got a reply, that my mail awaits moderation. That mail also contained a link. The link is dead since yesterday evening. Which does usually mean that the mail was posted, but it did not show up. I have enclosed the mail again below, Thanks, Lars Kunert The following attached (downsized) program implements a queue which contains a single worker process. Int's that are pushed into the queue are popped by the worker and processed... The problem is, the program ends up with an segmentation fault. Valgrind tells me that the stack is overwritten. ==4927== Conditional jump or move depends on uninitialised value(s) ==4927== at 0x8073536: strstr (in /local/home/lkunert/projects/pg-build-4.0.3/src/cdag/threads/queue_error) ==4927== by 0x80609F5: pthread_initialize (smp.h:47) ==4927== by 0x80B2DE1: (within /local/home/lkunert/projects/pg-build-4.0.3/src/cdag/threads/queue_error) ==4927== by 0x80480E8: (within /local/home/lkunert/projects/pg-build-4.0.3/src/cdag/threads/queue_error) ==4927== by 0x80641A0: __libc_csu_init (in /local/home/lkunert/projects/pg-build-4.0.3/src/cdag/threads/queue_error) ==4927== by 0x8063FC2: __libc_start_main (in /local/home/lkunert/projects/pg-build-4.0.3/src/cdag/threads/queue_error) ==4927== by 0x8048120: ??? (start.S:102) ==4927== ==4927== Syscall param write(buf) points to uninitialised byte(s) ==4927== at 0x8063044: write (in /local/home/lkunert/projects/pg-build-4.0.3/src/cdag/threads/queue_error) ==4927== by 0x804C241: boost::thread::thread(boost::function0<void, std::allocator<boost::function_base> > const&) (in /local/home/lkunert/projects/pg-build-4.0.3/src/cdag/threads/queue_error) ==4927== by 0x804AD26: QueueError::QueueError(unsigned) (QueueError.cxx:74) ==4927== by 0x8048287: main (QueueError.cxx:150) ==4927== Address 0x52BFE04C is on thread 1's stack Line 74 corresponds to the initailisation of the worker. The thread-manual writes: *explicit* thread(*const* boost::function0<*void*>& threadfunc); *Effects*: Starts a new thread of execution and constructs a thread <http://www.boost.org/doc/html/thread.html> object representing it. Copies |threadfunc| (which in turn copies the function object wrapped by |threadfunc|) to an internal location which persists for the lifetime of the new thread of execution. Calls |operator()| on the copy of the |threadfunc| function object in the new thread of execution. Which sound good to me. Were is the mistake. class QueueError { // *** Typedefs ************************************************************* private: typedef std::queue<int> Queue; typedef boost::thread Thread; public: typedef Queue::size_type ST; // *** Inner Classes ******************************************************** private: class Worker { private: QueueError* outer_p_; public: Worker( QueueError* outer_p ) : outer_p_( outer_p ) {}; public: void operator()() { outer_p_->worker_run_(); }; }; // *** Attributes ************************************************************ public: private: ST max_queue_size_; Queue queue_; Thread thread_; boost::mutex monitor_; boost::condition space_available_, job_available_; // *** Constructors / Destructors ******************************************** public: explicit QueueError( ST max_queue_size =1000 ) : max_queue_size_( max_queue_size ) , thread_( Worker( this )) {}; // *** Methods *************************************************************** public: void push( int i ) { boost::mutex::scoped_lock lock( monitor_ ); while( queue_.size() >= max_queue_size_ ) { space_available_.wait( lock ); }; queue_.push( i ); job_available_.notify_one(); }; protected: void worker_run_() { int i =0; while( true ) { i = worker_pop_(); worker_work_( i ); }; }; int worker_pop_() { boost::mutex::scoped_lock lock( monitor_ ); while( queue_.empty()) { job_available_.wait( lock ); }; int i = queue_.front(); queue_.pop(); space_available_.notify_one(); return i; }; void worker_work_( int i ) { for( int ii= 0; ii < i; ++ii ) { // do some work double divident = 10000; double sum; for( uint divisor =1; divisor < divident; ++divisor ) { sum = divident / divisor; }; }; }; }; // class QueueError int main() { QueueError q; q.push( 10 ); q.push( 9 ); q.push( 8 ); q.push( 7 ); q.push( 6 ); return 0; };

2 1

Compiling Boost 1.33.1 & getting success w/ XP!!
by Allen 27 Jan '07

27 Jan '07

Hello all, for those who'd had problems like be getting boost to run after getting it to compile in w/ their App, here's what I did: 1. Got the absolute latest version of boost that was stable - 1.33.1 2. Followed the "Getting Started" Instructions better: a. in step 2 for XP, HAD to start a cmd tool b. HAD to run vcvarsall.bat (located @ C:\Program Files\Microsoft Visual Studio 8\VC\vcvarsall.bat on my computer) c. I'm using the toolset vc-8_0, therefore the need for step 2.b d. cd'ed to my Boost install directory - after getting the bjam executable for XP and copying it there 1st e. ran the following commands C:\Program Files\Microsoft Visual Studio 8\VC\vcvarsall.bat <return> bjam "-sTOOLS=vc-8_0" install 3. Took over 2 hrs to get the results in a NEW BOOST directory where only the "includes" and the "libs" were located. 4. Notice that I accepted the "default" libs that it generated. The Note on using the "-sBUILD" NEVER NEVER worked for me. The build processes kept trying to use .Net 2003 VC7 to compile with & of course couldn't find it! So boost never built correctly to begin with. Bummer! 5. Then I included the header directory in my .Net App: C:\Boost\include\boost-1_33_1 6. Thin I included the following "static" libraries in my .Net App: C:\Boost\lib\libboost_wserialization-vc80-mt-gd-1_33_1.lib C:\Boost\lib\libboost_date_time-vc80-mt-gd-1_33_1.lib C:\Boost\lib\libboost_filesystem-vc80-mt-gd-1_33_1.lib C:\Boost\lib\libboost_iostreams-vc80-mt-gd-1_33_1.lib C:\Boost\lib\libboost_prg_exec_monitor-vc80-mt-gd-1_33_1.lib C:\Boost\lib\libboost_program_options-vc80-mt-gd-1_33_1.lib C:\Boost\lib\libboost_regex-vc80-mt-gd-1_33_1.lib C:\Boost\lib\libboost_serialization-vc80-mt-gd-1_33_1.lib C:\Boost\lib\libboost_signals-vc80-mt-gd-1_33_1.lib C:\Boost\lib\libboost_test_exec_monitor-vc80-mt-gd-1_33_1.lib C:\Boost\lib\libboost_thread-vc80-mt-gd-1_33_1.lib C:\Boost\lib\libboost_unit_test_framework-vc80-mt-gd-1_33_1.lib C:\Boost\lib\libboost_wave-vc80-mt-gd-1_33_1.lib 7. I've NO clue what "gd" means but I sure hope it means the debug version. The docs DON'T explain this nor the -s either and I hope their updated soon to include the meaning of these nomenclatures. Well that's all & it works for me, FINALLY!!!!!!!!!!!! I'm so happy. Just wish I'd had feed back from the group on this issue but all's well that ends well. See y'all later!!! -- Sincerely, Allen Gene Allen Saucier, Jr Senior Software Engineer CAS, Inc 100 Quality Circle Huntsville, AL 35806 or PO Box 11190 Huntsville, AL 35814 (256) 922-6453 (w) "...As for I and my house, we shall follow the Lord" Joshua 24:15

5 5

Re: [Boost-users] More on Newby question re (boost::shared_ptr) enable_shared_from_this
by ethann.castell＠caliton.com 26 Jan '07

26 Jan '07

I've manage to narrow down what the problem is and created a test case that simulates my real code. The problem occurs in a destructor (of B1) when it tries to get a shared pointer to shared_from_this() from its base class (base_class). I think that the execution of the destructor hierarchy has deleted the original shared_ptr to B2 meaning that the shared_from_this() returns an error (because shared_from_this() requires that the object is managed by a shared_ptr). My original destructor code was using raw pointers (ie. this) which worked fine because the base_class destructor was last to be called and was still alive at the time when ~B2() is called. This seems like it could be a limitation of boost::shared_ptr? I have placed my code in the destructor of B2 because in my program I am never sure exactly of the lifespan of B2. During execution I accumulate information in the B2 object and then write out this information at the end of its lifespan i.e in the destructor. I'm open to any ideas including any ways that I might be able to restructure my program. #include <boost/smart_ptr.hpp> #include <boost/enable_shared_from_this.hpp> #include <boost/scoped_ptr.hpp> #include <iostream> class base_class : public boost::enable_shared_from_this<base_class> { private: boost::shared_ptr<base_class> m_Linked; // link to another base_class public: base_class(){}; base_class( boost::shared_ptr<base_class> pLinked) { m_Linked = pLinked; // store link to other base class } }; class B : public base_class { public: B(boost::shared_ptr<base_class> pLinked) : base_class( pLinked){} }; class B1 : public B { public: B1(boost::shared_ptr<base_class> pLinked) : B( pLinked){} ~B1() { try{ boost::shared_ptr<base_class> ptr_This = shared_from_this(); // Exception occurs here // Write out some links here. } catch (exception &e) { std::cout << e.what(); } } }; class B2 : public B1 { public: B2(boost::shared_ptr<base_class> pLinked) : B1( pLinked){} }; class A : public base_class { public: A() : base_class(){}; int f; void Process() { boost::shared_ptr<base_class> ptr_me = shared_from_this(); // get pointer to myself //afterwards - use_count = 2, weak_count = 2 f = 3; if (f == 3){ boost::shared_ptr<B2> ptr_b2( new B2(ptr_me) ) ; // create new B2 and pass pointer to me. }else{ // crashes with bad_weak_ptr error on this line. } } }; void main() { boost::shared_ptr<A> ptr_a( new A() ); ptr_a->Process(); } // EOF

3 2

boost::mem_fn with Alexandrescu LockingProxy
by Allison Floyd 26 Jan '07

26 Jan '07

Hello, the list. After some digging through the bind and mem_fn documentation, I have been unable to figure out whether I'm attempting to do something impossible or not. I've created a thread-safe variant of shared_ptr that uses Alexandrescu's LockingProxy to ensure that access to the contained object through operator-> correctly locks and unlocks the pointee object. In all respects save one, this "shared_locking_ptr" is syntactically equivalent to boost::shared_ptr. The one thing it cannot do is dereference the pointer via operator* (I can't figure out how to return something from operator* that remains in scope (and thus locked) long enough for the operation to complete). All well and good so far. Where I'm trying to use this beast is in boost::signals via bind (and therefore mem_fn). I'd like to connect a member function of an object to the signal through my shared_locking_ptr, so that when the signal fires it automatically locks the object, invokes the member function, and then unlocks. Shared pointers to objects are valid arguments to mem_fn; my shared_locking_ptr isn't, alas, apparently because it requires the operator* mentioned above. So: 1) Has anybody else attempted to extend shared_ptr for Alexandrescu's policy-based storage types, specifically the LockingProxy, and figured out how to overload operator* in a meaningful way? or 2) Is there some way to wheedle signals, bind, and/or mem_fn so that they only access the slot through operator->, and don't try to dereference it? If this is more properly a boost developer's list question, let me know and I'll take it there. Thanks! -- Allison Floyd

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Re: [Boost-users] Compiling Boost 1.33.1 & getting success w/ XP!!
by Allen 26 Jan '07

26 Jan '07

Thank you Dave! However, I really don't know how to check the "cvs" repository. I'll look into it though. I'd appreciate a better getting started document. Thank you again.... --Allen > Today's Topics: > > 1. Re: Compiling Boost 1.33.1 & getting success w/ XP!! (David Klein) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Fri, 26 Jan 2007 16:58:21 +0100 > From: David Klein <dave_chp(a)gmx.de> > Subject: Re: [Boost-users] Compiling Boost 1.33.1 & getting success w/ > XP!! > To: boost-users(a)lists.boost.org > Message-ID: <45BA251D.3010504(a)gmx.de> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed > > Allen wrote: > > Hi Allen, > >> 2. Followed the "Getting Started" Instructions better: >> > There is a new and better "Getting Started" guide in cvs. > Look for more/getting_started.html. > >> 7. I've NO clue what "gd" means but I sure hope it means the debug >> version. The docs DON'T explain this nor the -s either and I hope >> their updated soon to include the meaning of these nomenclatures. >> > They do. Search in the current Getting Started guide under Results / > Runtime. > There is a table that lists everything. > > s - Static link to runtime. > g - Debug runtime. > y - Debug Python system. > d - Debug enabled code. > p - STLport runtime, instead of the vendor toolset runtime. > n - STLport runtime using the "native" IO streams instead of the STLport > IO streams. > > -- > HTH dave > > -- Sincerely, Allen Gene Allen Saucier, Jr Senior Software Engineer CAS, Inc 100 Quality Circle Huntsville, AL 35806 or PO Box 11190 Huntsville, AL 35814 (256) 922-6453 (w) "...As for I and my house, we shall follow the Lord" Joshua 24:15

2 1

When will BOOST settle how it constructs LIB and INCLUDE directories
by Allen 26 Jan '07

26 Jan '07

Hello all, just wondering when boost will finally settle in how it constructs the lib and include directories that we use to build our apps with so that I don't have to ALWAYS change the path names w/in my applications. This is really annoying. Anyone know? -- Sincerely, Allen Gene Allen Saucier, Jr Senior Software Engineer CAS, Inc 100 Quality Circle Huntsville, AL 35806 or PO Box 11190 Huntsville, AL 35814 (256) 922-6453 (w) "...As for I and my house, we shall follow the Lord" Joshua 24:15

2 1

[boost.signals] documentation suggestion + thread-safe partial implementation
by Frank Hess 26 Jan '07

26 Jan '07

Hi, I'd like to suggest a sentence be added to the boost.signals documentation describing how to connect one signal directly to another signal. It took me a while to realize I could do things like signal.connect(boost::bind(boost::ref(otherSignal), _2)); wrapping a signal object in a boost::ref() call before passing it to boost::bind(), to get around signals being noncopyable. Before this epiphany, I kept writing trivial wrapper functions to use as slots when I wanted to connect two signals :) I imagine others who are new to boost.signals and boost in general would resort to similar tactics. By the way, I hacked up a partial implementation of boost.signals which is intended to be thread-safe, since I missed boost.signals so much in my multi-threaded code. Would anyone would be interested in this? It's just a few header files, and depends on boost (although not on boost.signals). I just did the bare minimum I need for my own use: a signal template class, signalslib::connection, and signalslib::scoped_connection. I didn't implement return values because I don't use them. I didn't implement boost::trackable because I don't see how to make automatic connection management thread-safe when a signal is connected to an object's member function. You really want to insure the slot is disconnected from the signal before the object providing the slot is destroyed. Inheriting the object from boost::trackable wouldn't seem to be good enough, since the boost::trackable destructor wouldn't get called until after the object's destructor. So you pretty much have to manually disconnect the connection at the beginning of the object's destructor. -- Frank

1 0

[interval] using crlibm for transcendental functions
by Tobias Munk 26 Jan '07

26 Jan '07

I am using a custom rounding policy for transcendental functions, based on crlibm and defined in the manner of libs/numeric/interval/examples/transc.cpp In the documentation of crlibm, it is recommended to call the init function crlibm_init() before calling one of their transcendental functions. My question now is: does anybody know if calling this init function collides with any of the boost.numeric.interval internal algorithms? On i686 and amd64 crlibm_init() instructs the FPU not to use extended arithmetics: /* An init function which sets FPU flags when needed */ unsigned long long crlibm_init() { /* Set FPU flags to use double, not double extended, with rounding to nearest */ cw = (_FPU_DEFAULT & ~_FPU_EXTENDED)|_FPU_DOUBLE; _FPU_SETCW(cw); ... } Is it necessary to reset the old state after a call of a crlibm function, for correct interval arithmetics, or is one call of crlibm_init() for the whole program sufficient? Thanks, Tobias Munk --------------------------------- NEU: Fragen stellen - Wissen, Meinungen und Erfahrungen teilen. Jetzt auf Yahoo! Clever.

2 1

regex problem: removing two elements in a row?
by Lynn Allan 26 Jan '07

26 Jan '07

I want to use boost::regex 1.33.1 and vc7.1 on a WinXp-Sp2 computer to remove common words from a file. I'm encountering a problem which seems related to having two of the common words next to each other. std::string test(" in the beginning god created the heavens and the earth "); boost::regex reg; reg.assign("( and | can | did | the | in | a )"); test = boost::regex_replace(test, reg, " "); cout << test << endl; The result is: " the beginning god created heavens the earth " Am I doing something wrong or leaving out a step? Seems like the above ought to work. It catches one of the occurrences of " the " between " created " and " heavens " but not those immediately after the " in " or " and ".

2 4

boost::thread - problem with worker as an inner class of a queue
by Lars Kunert 26 Jan '07

26 Jan '07

The following attached (downsized) program implements a queue which contains a single worker process. Int's that are pushed into the queue are popped by the worker and processed... The problem is, the program ends up with an segmentation fault. Valgrind tells me that the stack is overwritten. ==4927== Conditional jump or move depends on uninitialised value(s) ==4927== at 0x8073536: strstr (in /local/home/lkunert/projects/pg-build-4.0.3/src/cdag/threads/queue_error) ==4927== by 0x80609F5: pthread_initialize (smp.h:47) ==4927== by 0x80B2DE1: (within /local/home/lkunert/projects/pg-build-4.0.3/src/cdag/threads/queue_error) ==4927== by 0x80480E8: (within /local/home/lkunert/projects/pg-build-4.0.3/src/cdag/threads/queue_error) ==4927== by 0x80641A0: __libc_csu_init (in /local/home/lkunert/projects/pg-build-4.0.3/src/cdag/threads/queue_error) ==4927== by 0x8063FC2: __libc_start_main (in /local/home/lkunert/projects/pg-build-4.0.3/src/cdag/threads/queue_error) ==4927== by 0x8048120: ??? (start.S:102) ==4927== ==4927== Syscall param write(buf) points to uninitialised byte(s) ==4927== at 0x8063044: write (in /local/home/lkunert/projects/pg-build-4.0.3/src/cdag/threads/queue_error) ==4927== by 0x804C241: boost::thread::thread(boost::function0<void, std::allocator<boost::function_base> > const&) (in /local/home/lkunert/projects/pg-build-4.0.3/src/cdag/threads/queue_error) ==4927== by 0x804AD26: QueueError::QueueError(unsigned) (QueueError.cxx:74) ==4927== by 0x8048287: main (QueueError.cxx:150) ==4927== Address 0x52BFE04C is on thread 1's stack Line 74 corresponds to the initailisation of the worker. The thread-manual writes: *explicit* thread(*const* boost::function0<*void*>& threadfunc); *Effects*: Starts a new thread of execution and constructs a thread <http://www.boost.org/doc/html/thread.html> object representing it. Copies |threadfunc| (which in turn copies the function object wrapped by |threadfunc|) to an internal location which persists for the lifetime of the new thread of execution. Calls |operator()| on the copy of the |threadfunc| function object in the new thread of execution. Which sound good to me. Were is the mistake. class QueueError { // *** Typedefs ************************************************************* private: typedef std::queue<int> Queue; typedef boost::thread Thread; public: typedef Queue::size_type ST; // *** Inner Classes ******************************************************** private: class Worker { private: QueueError* outer_p_; public: Worker( QueueError* outer_p ) : outer_p_( outer_p ) {}; public: void operator()() { outer_p_->worker_run_(); }; }; // *** Attributes ************************************************************ public: private: ST max_queue_size_; Queue queue_; Thread thread_; boost::mutex monitor_; boost::condition space_available_, job_available_; // *** Constructors / Destructors ******************************************** public: explicit QueueError( ST max_queue_size =1000 ) : max_queue_size_( max_queue_size ) , thread_( Worker( this )) {}; // *** Methods *************************************************************** public: void push( int i ) { boost::mutex::scoped_lock lock( monitor_ ); while( queue_.size() >= max_queue_size_ ) { space_available_.wait( lock ); }; queue_.push( i ); job_available_.notify_one(); }; protected: void worker_run_() { int i =0; while( true ) { i = worker_pop_(); worker_work_( i ); }; }; int worker_pop_() { boost::mutex::scoped_lock lock( monitor_ ); while( queue_.empty()) { job_available_.wait( lock ); }; int i = queue_.front(); queue_.pop(); space_available_.notify_one(); return i; }; void worker_work_( int i ) { for( int ii= 0; ii < i; ++ii ) { // do some work double divident = 10000; double sum; for( uint divisor =1; divisor < divident; ++divisor ) { sum = divident / divisor; }; }; }; }; // class QueueError int main() { QueueError q; q.push( 10 ); q.push( 9 ); q.push( 8 ); q.push( 7 ); q.push( 6 ); return 0; };

1 0

problem with boost::strong_components
by Tamas Marki 26 Jan '07

26 Jan '07

Hello, I'm trying to use the boost library's strong_components function to partition a graph to connected sub-partitions, and ran into a problem. Namely, when I generate the graph, for some reason the 'names' (indices) of the vertices have some gaps (basically the graph that needs to be partitioned is generated from another graph by throwing out a bunch of vertices). When I pass this graph to the function, it will count the left out vertices and treat them as 1-vertex sub-partitions, which is not desired. I then tried to use the vertex_index_map named parameter, that I thought would solve this. I used something like this (not the actual code as it would be too big) std::vector<int> other; // fill up the vector with the vertices by pushing back each one. The number of vertices is about 170k and the biggest vertex index is about 260k. // .. // bigedges and bigweights have the edges and the weights, dim is the total number of vertices - all these are checked and proper. graph_t cityg (bigedges.begin (), bigedges.end (), bigweights.begin (), dim); std::vector<int> component(num_vertices(cityg)); int num = strong_components(cityg, &component[0], boost::vertex_index_map (&other[0])); I must be doing it wrong, since it segfaults. The documentation says "This maps each vertex to an integer in the range [0, num_vertices(g))", that's why I thought it would work this way, but it does not. The obvious solution would be to throw out 1-vertex partitions, but I'd really like to know what's the proper way of doing this. Thanks in advance for any help! Tamas

1 0

Link errors with boost regex 1_33_1, Stlport 5.0 and MSVC8
by Manish Mangal 25 Jan '07

25 Jan '07

Hi I have a sample code just to check if I can link to boost regex The code is : #include <boost/regex.hpp> bool testregex( const char* StringToMatch ) { return( boost::regex_match( StringToMatch, boost::regex("[A-Z]+") )); } int main (int argc, char *argv[]) { bool trial = testregex( "hello how r u ?"); return 1; } I am in dll mode both in debug and release versions. The release version compiles, links and runs successfully The debug build, however throws two linker errors: I error LNK2019: unresolved external symbol "public: bool __thiscall boost::re_detail::perl_matcher<char const *,class stlpd_std::allocator<struct boost::sub_match<char const *> >,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > >::match(void)" (?match@?$perl_matcher@PBDV?$allocator@U?$sub_match@PBD@boost@@@stlpd_st d@@U?$regex_traits@DV?$w32_regex_traits@D@boost@@@boost@@@re_detail@boos t@@QAE_NXZ) referenced in function "bool __cdecl boost::regex_match<char const *,class stlpd_std::allocator<struct boost::sub_match<char const *> >,char,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > >(char const *,char const *,class boost::match_results<char const *,class stlpd_std::allocator<struct boost::sub_match<char const *> > > &,class boost::basic_regex<char,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > > const &,enum boost::regex_constants::_match_flags)" (??$regex_match@PBDV?$allocator@U?$sub_match@PBD@boost@@@stlpd_std@@DU?$ regex_traits@DV?$w32_regex_traits@D@boost@@@boost@@@boost@@YA_NPBD0AAV?$ match_results@PBDV?$allocator@U?$sub_match@PBD@boost@@@stlpd_std@@@0@ABV ?$basic_regex@DU?$regex_traits@DV?$w32_regex_traits@D@boost@@@boost@@@0@ W4_match_flags@regex_constants@0@@Z) 1>Main.obj : error LNK2019: unresolved external symbol "public: __thiscall boost::re_detail::perl_matcher<char const *,class stlpd_std::allocator<struct boost::sub_match<char const *> >,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > >::perl_matcher<char const *,class stlpd_std::allocator<struct boost::sub_match<char const *> >,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > >(char const *,char const *,class boost::match_results<char const *,class stlpd_std::allocator<struct boost::sub_match<char const *> > > &,class boost::basic_regex<char,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > > const &,enum boost::regex_constants::_match_flags,char const *)" (??0?$perl_matcher@PBDV?$allocator@U?$sub_match@PBD@boost@@@stlpd_std@@U ?$regex_traits@DV?$w32_regex_traits@D@boost@@@boost@@@re_detail@boost@@Q AE@PBD0AAV?$match_results@PBDV?$allocator@U?$sub_match@PBD@boost@@@stlpd _std@@@2@ABV?$basic_regex@DU?$regex_traits@DV?$w32_regex_traits@D@boost@ @@boost@@@2@W4_match_flags@regex_constants@2@0@Z) referenced in function "bool __cdecl boost::regex_match<char const *,class stlpd_std::allocator<struct boost::sub_match<char const *> >,char,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > >(char const *,char const *,class boost::match_results<char const *,class stlpd_std::allocator<struct boost::sub_match<char const *> > > &,class boost::basic_regex<char,struct boost::regex_traits<char,class boost::w32_regex_traits<char> > > const &,enum boost::regex_constants::_match_flags)" (??$regex_match@PBDV?$allocator@U?$sub_match@PBD@boost@@@stlpd_std@@DU?$ regex_traits@DV?$w32_regex_traits@D@boost@@@boost@@@boost@@YA_NPBD0AAV?$ match_results@PBDV?$allocator@U?$sub_match@PBD@boost@@@stlpd_std@@@0@ABV ?$basic_regex@DU?$regex_traits@DV?$w32_regex_traits@D@boost@@@boost@@@0@ W4_match_flags@regex_constants@0@@Z) Any help is appreciated Manish Mangal Software Engineer atlas(r) search Partner for Results 206-816-8349 // phone Manish.Mangal(a)AtlasSolutions.com <mailto:t-Matt.Koch@AtlasSolutions.com> // email www.AtlasSolutions.com <outbind://116-000000001368D4B5F8F6D0488191444C76FD7C9507008921F4CB773B0 545AAED425DEF553BC300003A3500100000DB0C51F64BED3447AA6EC585072C4EC300000 1E3B7A70000/jenniferh/Local%20Settings/Temporary%20Internet%20Files/OLK3 /www.AtlasSolutions.com> // web

1 0

How can I develop generic test code and using it with the test_suite
by Stephen Torri 25 Jan '07

25 Jan '07

I have the following code for a sample test. I was wondering how I can move code that is common to a long off different test files to a common location and use inheritance? In the code below I can do two things. If its indeed generic I can encapsulate it in a common class used in the tests. Secondly I could put test_one and test_two in a class and inherit from the parent generic class. What is the best solution for what I am trying to do? Stephen ----------CODE-------------- #include <boost/test/unit_test.hpp> #include <fstream> using namespace boost::unit_test; using namespace boost::unit_test_framework; class A {} class B {} A* helper_run_test ( B& target_ref, std::string target_file ) { ... do work on B and return A* result } void test_one () { B& b_ref; A* helper_run_test ( b, "Apple" ); .. perform a BOOST_CHECK_EQUAL } void test_two () { B& b_ref; A* helper_run_test ( b, "Peach" ); .. perform a BOOST_CHECK_EQUAL } test_suite* init_unit_test_suite ( int, char**) { test_suite* test = BOOST_TEST_SUITE ("My test suite"); test->add ( BOOST_TEST_CASE ( &test_one ) ); test->add ( BOOST_TEST_CASE ( &test_two ) ); return test; }

3 3

[type_traits] superfluous add_pointer in function_traits or something else?
by Pavel Antokolsky aka Zigmar 25 Jan '07

25 Jan '07

Hello! I'm trying to use function_traits but it fails to compile. It seems like the add_pointer is somehow related to the error, as using the helper struct directly (and thus avoiding add_pointer on supplied type) compiles ok. I'm using boost 1.30.2 with g++ 3.2.2 on linux. The minimal example is: #include <boost/type_traits/function_traits.hpp> int foo() {} template<typename T> void bar(T f) { typedef typename boost::function_traits<T>::result_type X; //fails to compile typedef typename boost::detail::function_traits_helper<T>::result_type Y; //OK } int main(int argc, char** argv) { bar(foo); } The compiler output is: $ g++ func_traits.cpp func_traits.cpp: In instantiation of `boost::function_traits<int (*)()>': func_traits.cpp:7: instantiated from `void bar(T) [with T = int (*)()]' func_traits.cpp:13: instantiated from here func_traits.cpp:7: base class `boost::detail::function_traits_helper<int (**)()>' has incomplete type func_traits.cpp: In function `void bar(T) [with T = int (*)()]': func_traits.cpp:13: instantiated from here func_traits.cpp:7: no type named `result_type' in `struct boost::function_traits<int (*)()>' Is I'm using function_traits wrong or there is something wrong with the implementation? And another small thing that looks a bit strange to me: for some reason boost/type_traits.hpp does not link boost/type_traits/function_traits.hpp, but it never mentioned in documentation. -- Best regards, Zigmar

2 3

[boost::serialization] want access to binary data sans bookkeeping data
by Brian Stempel 25 Jan '07

25 Jan '07

Hi, I am wanting to serialize some C++ data structures into a binary stream, and I'm wanting to send that binary stream to an embedded python interpreter, where it can unpack the data and make use of it. So, this doesn't seem like a typical use of the serialization library, but I was wondering if it can still work. My problem is that it appears (from what I can tell) that there are various administrative bits inserted by the serialization library into the binary stream, meant for the "unserializer" to make use of in some way (e.g. a header, version information, etc.) Of course, this would mess up things for my python reader. I'd like to, as efficiently as possible, serialize, say, a 3d vector into a binary stream of 3 floats, and then send the raw binary data as an argument to a python function, and have the python function unpack this into 3 floats. This just a simple example though, but as long as the sender (C++) and the receiver (Python) both know the format, I could send arbitrary information this way, as long as there's no other bookkeeping data in the stream. Is there any way to gain access to the raw binary data, after I've filled things with my binary_oarchive, so I can send it to my python function? Or is this just not really a good use of serialization? Thanks!

3 8

[boost-thread] Communication between Threads
by Meryl Silverburgh 25 Jan '07

25 Jan '07

Hi, I notice there is a boost.thread library, but is there a library for inter-threads communication? For example, is there a 'Procedure/Consumer' example for inter-threads communications? Thank you.

4 5

[interprocess] another newbie question: clean-up
by Wolfgang Hottgenroth 24 Jan '07

24 Jan '07

Hi, after I go really quick help here from Ion, I've another question. I managed it to implement a map<string, string> in shared memory and I'm able to put pairs into the map in one process and read them in another process. To put pair into the map I wrote: typedef boost::interprocess::allocator<char, boost::interprocess::managed_shared_memory::segment_manager> ShmemStringAllocator; typedef boost::interprocess::basic_string<char, char_traits<char>, ShmemStringAllocator> MyString; MyString key(segment.get_segment_manager()); MyString value(segment.get_segment_manager()); key = "key1"; value = "value1"; mymap->insert(std::pair<MyString, MyString>(key, value)); (For the complete code see http://www.hottis.de/boost/strings/. Thanks.) What I'm wondering is: will the memory required for key and value be freed automatically in the writing process (put.C)? When I like to erase an element from the map, do I need to do more than just calling mymap->erase(key)? And finally when I'm done and like to remove the whole map, is more required than segment.destroy<MyMap>("MyMap")? Will all the MyString's in the map go too? Furthermore: is it possible to use a map in shared memory as an associative array and write: MyString value = (*mymap)[key]; It doesn't compile for me. Thanks, Wolfgang

2 3

[fusion][mpl::math] generic math operations
by Chris Weed 24 Jan '07

24 Jan '07

Hi, I am interested in combining the fusion and mpl::math libraries, but I am not sure if they currently support what I want to do. I want to use generic math operations that can easily switch between run-time and compile-time. I think this would require writing the mpl::math functions as "Polymorphic Function Object" as described in the fusion documentation. I am not sure if there is any mpl::math documentation that describes this. It looks like the MPL currently has some math operations that are strictly meta-functions in boost/mpl/aux_/arithmetic_op.hpp. Are the any plans to expand these to be functions also? Chris

4 13

code snippet to add line number to lexical_cast exceptions
by bert hubert 24 Jan '07

24 Jan '07

Hi people, I find that I rely on lexical_cast<> a lot, it is a great thing. However, when it throws an exception, and I catch it, I lose information on which of the many lexical_casts had a problem. This is not a lexical_cast specific problem of course, it would be great to have a more general way to add line numbers to exceptions! This led me to code up this small gcc specific hack, but I wonder if there is a better way: #define wrapped_atox(x, y) ({ \ x tmp; \ try { tmp=boost::lexical_cast<x>(y); } \ catch(exception &e) { \ throw std::runtime_error(std::string("On line " + \ boost::lexical_cast<std::string>(__LINE__)+" of " +\ std::string(__PRETTY_FUNCTION__)+" in " +std::string(__FILE__) +\ ", while converting '"+string(y)+"': ") + e.what()); \ } \ tmp; \ }) Which can be used as: cout << wrapped_atox(int, argv[1]) << endl; The code above works, but is gcc specific, and well, it doesn't look right. Perhaps someone has a better idea? Otherwise, people may benefit from the snippet above, feel free to copy it! Bert -- http://www.PowerDNS.com Open source, database driven DNS Software http://netherlabs.nl Open and Closed source services

1 0

Missing libboost_random ?
by Koen Deforche 24 Jan '07

24 Jan '07

All, I'm trying to use some of the functions in the boost random library. I get linking errors on: undefined reference to `boost::random_device::random_device(std::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)' It turns out I do not find any libboost_random.so and none of the installed library has the symbol random_device. Are they missing? Are we not yet supposed to use Boost.Random ? This is the case with both the libraries provided by my distribution (both gentoo and fedora core) as well as a CVS snapshot that I compiled myself. Where are they ? Regards, koen

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[mpl] compile time integer power
by Sami 23 Jan '07

23 Jan '07

Hi All, This is a newbie mpl question, and here goes: How can evaluate integer powers using mpl? Such as, template < unsigned Pow, class Real > Real pow( Real r ) { return <compile time r*r*r* ... r > ; // the expression is compile time, // not the result of course. } int main() { float k = pow<6>(3.14f); return k; // just kidding :) } An also as a side question, is there a wrapper type container (or iterator?) that holds a given constant value (or type)? Such as, the aptly named "constant_wrapper" used below with fold algorithm, using namespace boost::mpl; const unsigned SIZE = 5; typedef fold < constant_wrapper< int_<-3>, SIZE> , int_<0> , plus<_,_> >::type number; BOOST_STATIC_ASSERT( number::value == -3*SIZE ); Thanks a lot

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boost::unit_test::framework needs fini_unit_test_suite
by pwm 23 Jan '07

23 Jan '07

I have just run into an issue with using boost unit test. To initialize a test one must implement a function init_unit_test_suite. There needs to be an analogous fini_unit_test_suite so the test suite can properly release any resources acquired by the init method. Phil

2 1

[pool] object_pool::destroy_all?
by Michael Marcin 23 Jan '07

23 Jan '07

I started using object_pool recently to solve a problem. I have lots of objects being created and destroyed frequently and stored in a collection. Every so often an event happens which triggers destroying all the objects. Essentially I have: boost::object_pool<Object> m_object_pool; std::vector<Object*> m_objects; Then I have a function void DestroyAllObjects() { std::vector<Object*>::iterator it, iend = m_objects.end(); for( it = m_objects.begin(); it != iend; ++it ) { m_object_pool.destroy(*it); } m_objects.clear(); } It seems like there should be a better way of doing this... i.e. void DestroyAllObjects() { m_object_pool.destroy_all(); m_objects.clear(); } Also it might be nice to iterate over all the objects in the pool (in which case I wouldn't even need the m_objects vector. Perhaps there is a better way to solve the problem? Thanks, Michael Marcin

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Re: [Boost-users] [general question] on threading anddoublecheckedlocking pattern
by Sohail Somani 23 Jan '07

23 Jan '07

> -----Original Message----- > From: boost-users-bounces(a)lists.boost.org > [mailto:boost-users-bounces@lists.boost.org] On Behalf Of > Jason Olenhouse > > Meyers and Alexandrescu have commented on this as well: > http://www.aristeia.com/Papers/DDJ_Jul_Aug_2004_revised.pdf A very good article I might add.

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[Boost 1.33.1].[64-bit]
by Prashant Thakre 23 Jan '07

23 Jan '07

Hi, I am trying to get 64-bit build of Boost 1.33.1 on following platforms: 1.Solaris 10 - Sun Studio 11 - Sparc. URL's listed below helped me to build some if not all. Patch -- http://blogs.sun.com/sga/entry/boost_1_33_1 Instruction for passing the relevant options to bjam -- http://blogs.sun.com/sga/category/Boost 2.HP-UX 11.23 - aCC A.06.02 - Itanium. How do I pass "+DD64" option to the compiler and the linker for 64-bit build. 3.AIX 5.3 - xlC/C++ 8.0 - PowerPC. Correct way to pass "-q64" option to the compiler and the linker. I do not really want to use the environment variable OBJECT_MODE. -- regards, Prashant Thakre

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gdb and Invalid Address specified to RtlFreeHeap
by gelbeiche 23 Jan '07

23 Jan '07

Hi, I have an C++ application that uses the Oracle OCI libraries(oci.dll), which itself has references to msvcr71.dll. I compiled the application with gcc 3.4.2 under MinGW and for runtime usage I downloaded/installed the desired msvcr71.dll. From "installed.ini": [components] runtime=mingw-runtime-3.11.tar.gz w32api=w32api-3.8.tar.gz ... The program crashed at exit with the following error message in a dialog window: Microsoft Visual C++ Runtime Library Runtime Error ! abnormal program termination Because I want debug the error I installed gdb 5.2.1. When I run the program in gdb I get the following message: Program received signal SIGTRAP. Trace/breakpoint trap. ... warning: HEAP[...] warning: Invalid Address specified to RtlFreeHeap(230000, 246950) In the backtrace I see that it happens in OCIInitialize. So I suppose it has something to do with the oci.dll and msvcr71.dll. But I'm able to run the application outside the debugger and beside the crash at exit it is working. How can I debug my application ? My OS is Windows2000. Thomas -- http://www.randspringer.de

2 1

typesafe typedef that is not implicitly convertible
by pwm 23 Jan '07

23 Jan '07

I am unable to find it now, but I thought I saw that there is a boost way to define a typedef using a unique class that cannot be implicitly converted to another type. Thus, typedef int Foo; void bar( Foo a ); would compile only with bar( Foo(3) ) not bar(3) Is this capability in Boost 1.33 or am I hallucinating? Thanks, Phil

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Re: [Boost-users] [general question] on threading anddoublecheckedlocking pattern
by Sohail Somani 23 Jan '07

23 Jan '07

Actually, its not so much wrong as it is "working currently but will probably break at some stage". Apparently, since Solaris always runs in "total storage ordering" mode, their implementation of pthread_once is correct for those hardware platforms. Just thought I'd clarify that. > -----Original Message----- > From: Sohail Somani > Sent: Monday, January 22, 2007 7:25 PM > To: 'boost-users(a)lists.boost.org' > Subject: RE: [Boost-users] [general question] on threading > anddoublecheckedlocking pattern > > Oopsie: > > http://bugs.opensolaris.org/view_bug.do?bug_id=6513516 > > So even the smart guys get it wrong. > > > -----Original Message----- > > From: boost-users-bounces(a)lists.boost.org > > [mailto:boost-users-bounces@lists.boost.org] On Behalf Of > > Sohail Somani > > Sent: Monday, January 22, 2007 5:12 PM > > To: boost-users(a)lists.boost.org > > Subject: Re: [Boost-users] [general question] on threading > > anddoublecheckedlocking pattern >

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Re: [Boost-users] [general question] on threading anddoublecheckedlocking pattern
by Sohail Somani 23 Jan '07

23 Jan '07

Oopsie: http://bugs.opensolaris.org/view_bug.do?bug_id=6513516 So even the smart guys get it wrong. > -----Original Message----- > From: boost-users-bounces(a)lists.boost.org > [mailto:boost-users-bounces@lists.boost.org] On Behalf Of > Sohail Somani > Sent: Monday, January 22, 2007 5:12 PM > To: boost-users(a)lists.boost.org > Subject: Re: [Boost-users] [general question] on threading > anddoublecheckedlocking pattern

2 1

[multiindex] key extractor as free function - how?
by Markus Werle 23 Jan '07

23 Jan '07

Hi! I read from the docs that we can define key extractors to be one of - identity - member - mem_fun - composite_key Is it possible to use a free function as key extractor in the same way as the ones listed above and can you give an example of this? reagrds, Markus

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Where to get boost 1.32 for solaris c++
by Victor Cheng 23 Jan '07

23 Jan '07

It seems that sun c++ has problems compiling boost 1.33.1 and the most compatible version is 1.32, but I could not find it any where on www.boost.org. It's probably in the cvs repository, but can't find the tag for 1.32. Is there a place where I can download this version?

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[multiindex] combination with boost::tuple
by Markus Werle 23 Jan '07

23 Jan '07

Hi! I'd like to use boost::tuple in a list-replacing multiindex and use the first entry in the tuple as key. The following fails to compile. Could you please provide a correction? #include <boost/tuple/tuple.hpp> #include <boost/multi_index_container.hpp> #include <boost/multi_index/sequenced_index.hpp> #include <boost/multi_index/key_extractors.hpp> namespace bm = ::boost::multi_index; class C { typedef boost::tuple<std::string, std::string> data_t; template <typename T> struct mutable_value { mutable_value(const T& t):t(t){} operator T&()const{return t;} private: mutable T t; }; typedef bm::multi_index_container <mutable_value<data_t>, bm::indexed_by <bm::sequenced<>, bm::ordered_unique <bm::mem_fun<data_t, std::string, &data_t::get<0> > > > > storage_t; storage_t storage_; }; int main() { C c; }

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compiling boost using codewarrior for windows
by Jean-Marc 23 Jan '07

23 Jan '07

when compiling boost ( the cvs version ) with metrowerks codewarrior for windows, I get a huge amount of errors. Is this (great !) compiler supported by boost ? Many thanks for your help Regards JM

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[pool] fixed-size allocation pool
by Michael Marcin 23 Jan '07

23 Jan '07

I was wondering if I could use boost::pool for a fixed-sized object pool and return NULL if it tries to construct more than the maximum. Reading http://www.boost.org/libs/pool/doc/implementation/object_pool.html it seems like I could if I set_next_size(0) but it explicitly says I should not do that. Is there a reason to not support this behavior or is it supported in some other way/library? Thanks, Michael Marcin

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Re: [Boost-users] [general question] on threading and doublecheckedlocking pattern
by Sohail Somani 23 Jan '07

23 Jan '07

It definitely is. But if you could find a way to make it better, even with complicated and platform-dependent code, and then wrap it up into something usable, have it tested and peer-reviewed, and placed somewhere we could all use it, it would still be useful. -------------- Sure -------------- P.S. In this particular case, I don't think you can get better than: - a read barrier and if-branch in the already-initted case - that + a write barrier in the init case - all wrapped into a single int. which is slightly, but not much better than a mutex. It is also slightly better than most implementations of boost::once/pthread_once, and much better than some, depending on platform. -------------- What I've found that pthread_once implementations end up using DBCL anyway but the benefit of using it there is obviously that you don't have to debug it since they put in the necessary barriers. As far as I'm concerned the problem is solved. For the 0.0001% of C++ programmers that actually need the performance and are willing to shell out the debugging hours, they are more than welcome. I (personally) think a boost singleton based on boost once would be good enough for everyone else until there are solutions per os/hw combination. Do you think people would like one? Not to take away from your valid points of course. Sohail

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Re: [Boost-users] [general question] on threading and double checkedlocking pattern
by Sohail Somani 22 Jan '07

22 Jan '07

> -----Original Message----- > From: boost-users-bounces(a)lists.boost.org > [mailto:boost-users-bounces@lists.boost.org] On Behalf Of > Ovanes Markarian > > I might be wrong here, but I would like to hear some thoughts > of C++ professionals. > > I read in lots of sources about DCLP and how it is broken in > conjunction with Singleton pattern > and my question is of a very simple nature. Is it possible to > solve this problem by introducing > function calls via function pointers? Or is there still a > way, that these calls might be inlined > and if yes then how could this look like? This example is not > about freeing the singleton, it is > just about creating it. Hi, Perhaps the path-of-least-debugging is to use boost::once? Sohail

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[general question] on threading and double checked locking pattern
by Ovanes Markarian 22 Jan '07

22 Jan '07

I might be wrong here, but I would like to hear some thoughts of C++ professionals. I read in lots of sources about DCLP and how it is broken in conjunction with Singleton pattern and my question is of a very simple nature. Is it possible to solve this problem by introducing function calls via function pointers? Or is there still a way, that these calls might be inlined and if yes then how could this look like? This example is not about freeing the singleton, it is just about creating it. class Singleton; typedef Singleton* (*singleton_getter)(); class Singleton : boost::noncopyable { static Singleton* pInstance; static singleton_getter getter; //other internal data... Singleton(); static Singleton* creating_singleton_getter(); static Singleton* non_creating_singleton_getter(); public: static Singleton* instance(); }; //implementation Singleton* Singleton::pInstance = NULL; singleton_getter Singleton::getter = &creating_singleton_getter; Singleton::Singleton() {} Singleton* Singleton::creating_singleton_getter() { //aquire mutex here if(Singleton::pInstance==NULL) Singleton::pInstance = new Singleton; Singleton::getter = &non_creating_singleton_getter; return Singleton::pInstance; } //mutex unlocked Singleton* Singleton::non_creating_singleton_getter() { //no mutex anymore return Singleton::pInstance; } Singleton* Singleton::instance() { return (Singleton::getter)(); } With Kind Regards, Ovanes Markarian

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[date_time] Misparses POSIX timezone specs
by Stephen Turner 22 Jan '07

22 Jan '07

If I'm being stupid, tell me; but I believe the date_time library misreads all POSIX timezone specs by swapping + and -. It uses negative for west of Greenwich, but POSIX (admittedly unintuitively) uses negative for east of Greenwich. Compare this Linux box: [chiark:~] (1)% date Fri Jan 19 16:05:53 GMT 2007 [chiark:~] (2)% setenv TZ PST8 [chiark:~] (3)% date Fri Jan 19 08:06:04 PST 2007 with this code which wraps the date_time library (the internals aren't important): DWORD dw1 = 1149163201; // 1 June 2006 12:00:01 GMT CMyTime::set_timezone_posix("PST8"); CMyTime t = dw1; h = t.GetHour(); // h = 20 -- Stephen Turner, Cambridge, UK http://homepage.ntlworld.com/adelie/stephen/ "The internet is a reflection of our society. If we do not like what we see, the problem is not to fix the mirror, we have to fix society." (Vint Cerf)

2 1

[bind] Problem compiling when passing instantiation of class
by Paul Giaccone 22 Jan '07

22 Jan '07

I am using Boost bind in conjunction with Boost unit test, as I have many times before, but I can't get my code to compile. I've looked at http://boost.org/libs/bind/bind.html#Troubleshooting but don't see anything that covers my case. Here is the line that is failing (with disguised variable names): test_suite -> add(BOOST_TEST_CASE(boost::bind(my_test, obj1, obj2, obj3, 1.0, obj4, 10, 1E-9, results))); and here is the error that Microsoft Visual C++ .NET is generating: main.cpp(152): error C2665: 'boost::bind' : none of the 2 overloads can convert parameter 4 from type 'Obj3Type' The variables obj3 and obj4 are of type Obj3Type and Obj4Type respectively (see definitions below): The function my_test is defined as: void my_test(boost::shared_array<Vector>& a, boost::shared_array<Vector>& b, Obj3Type& c, const double d, const Obj4Type& e, const unsigned int f, const double g, boost::shared_array<std::pair<double, std::valarray<double> > >& h) where Obj3Type and Obj4Type are defined as: class Obj3Type { bool var1; unsigned int var2; unsigned int var3; double var4; double var5; MyType var6; boost::scoped_array<int> var7; boost::scoped_array<boost::scoped_array<double> > var8; }; struct Obj4Type { MyType var1; double var2; double var3; double var4; double var5; double var6; Vector var7; Vector var8; double var9; bool var10; } where MyType is an enumerated type and Vector is another struct of mine. (Where I have used structs rather than classes, this is for convenience.) Note that obj4 does not generate a compiler error, even when I move it to appear before obj3 in the parameter list. I wondered if it was necessary to overload operator= for Obj3Type as, presumably, the compiler cannot generate it for the scoped arrays in that struct but can for everything in Obj4Type, including Vector, for which I have defined operator=. I wrote an operator= for Obj3Type, but it made no difference to the compiler error. This was to be expected really, as obj3 is passed by reference rather than by value. Does it have anything to do with using structs instead of classes? I can't see how that could be the case. So what am I missing here? Thanks for any help.

2 2

Glib::ustring and tokenizer
by Manuel Jung 22 Jan '07

22 Jan '07

Hi everybody, I want to use Glib::ustring for UTF8 support. I was using boost::tokenizer up to this moment for breaking up some strings, which now would be ustrings. In the tokenizer Documentation you can find: template < class TokenizerFunc = char_delimiters_separator<char>, class Iterator = std::string::const_iterator, class Type = std::string > class tokenizer Im never used template programming, so can somebody give me a hint, if and how i can modify this to Glib::ustring? Maybe something like this? template < class TokenizerFunc = char_delimiters_separator<char>, class Iterator = Glib::ustring::const_iterator, class Type = Glib::ustring > class utokenizer Can i use wchar_t now? im a liddle bit confused, if it not works i have just to write some code myself, but i have hope getting it working. Thanks for reading and maybe some answers. Greetings from stormy germany Manuel Jung

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Re: [Boost-users] [filesystem] code pages support
by Nat Goodspeed 22 Jan '07

22 Jan '07

________________________________________ From: boost-users-bounces(a)lists.boost.org [mailto:boost-users-bounces@lists.boost.org] On Behalf Of ????? ???????? Sent: Friday, January 19, 2007 10:41 AM To: boost-users(a)lists.boost.org Subject: [Boost-users] [filesystem] code pages support namespace fs = boost :: filesystem; boost :: intmax_t filesize = fs :: file_size (argv [1]); This causes an exception if the name consists of cyrillic symbols. (Windows XP, MinGW). Does boost :: filesystem support these names. [Nat] Maybe try: boost :: intmax_t filesize = fs :: file_size (fs::path(argv [1], fs::no_check)); This uses an explicit conversion to fs::path rather than an implicit one, which allows you to explicitly disable the path syntax checker. I always disable the path syntax checker. It doesn't even support ASCII names well. ;-)

1 0

Newby question re (boost::shared_ptr) enable_shared_from_this
by ethann.castell＠caliton.com 22 Jan '07

22 Jan '07

Hi, I'm still fairly new to C++ and I'm in the process of converting pointers to boost shared pointers. I have a question regarding the use of enable_shared_from_this. I would like to store a self-referencing pointer within the object. Something like: class someclass : public boost::enable_shared_from_this<someclass> { protected: boost::shared_ptr<someclass> m_ptr_this; someclass() { m_ptr_this = shared_from_this(); } } And then access m_ptr_this in classes derived from someclass, and pass as a parameter to methods of other (derived or non-derived) classes. eg. class someclass2 : public someclass { ... some_func(){ someclass3* f = new someclass3(); someclass3->do_something( m_ptr_this ); } } I understand that using a shared_ptr (without enable_shared_from_this) to self-reference will lead to problems because the reference count of the pointer will never reach zero and therefore the memory will never get released. But as enable_shared_from_this uses a weak pointer internally, does this get around the problem? I'm getting a little confused because it gets typecast from weak_ptr to shared_ptr and I'm not sure what this leads to. I've also considered having a member function return the pointer: boost::shared_ptr<someclass> someclass::get_this() { return shared_from_this(); } and then calling the routine like this; someclass3->do_something( get_this() ); but I think that this will cause a problem because the documentation says not to use boost pointers which are only created as temporary variables. i.e. store all boost pointers in vars. What I'm hoping to do is avoid having to declare extra shared_ptr vars all over the place. Any help will be most appreciated. And I'll owe you a beer! Regards Ethann Castell

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program_options: Why it throw ambiguous_option?
by Peng Yu 22 Jan '07

22 Jan '07

Hi, I got the following error for the program list below. Where program_options considers "help" and "help_abc" as ambiguous? $ ./main --help terminate called after throwing an instance of 'boost::program_options::ambiguous_option' what(): ambiguous option help Aborted Thanks, Peng #include <boost/program_options.hpp> namespace po = boost::program_options; int main(int ac, char* av[]) { po::options_description desc("Allowed options"); desc.add_options() ("help", "produce help message") ("help_abc", po::value<int>(), "set compression level") ; po::variables_map vm; po::store(po::parse_command_line(ac, av, desc), vm); po::notify(vm); return 0; }

1 0