November 2007 - Boost-users - lists.preview.boost.org

Best way to create objects of arbitrary length and types
by Roman Morokutti 23 Nov '07

23 Nov '07

Hi, what would be the best solution to create objects of variable length and arbitrary types in C++ which are best in performance and size respectively. Or is there a solution in boost for this kind of problem anyway? These objects would be written in a queue for asynchron processing. Thanks in advance. Roman

1 0

Error when trying to use johnson_all_pairs_shortest_paths ( ) function
by Sangameshwar Patil 23 Nov '07

23 Nov '07

Hi, I am getting following error when trying to use the johnson_all_pairs_shortest_paths( ) function in boost graph library (BGL). "no matching function for call to johnson_all_pairs_shortest_paths(boost::adjacency_list<boost::setS, boost::vecS, boost::bidirectionalS, boost::property<boost::vertex_name_t, std::string, boost::no_property>, boost::property<boost::edge_weight_t, int, boost::property<boost::edge_weight2_t, int, boost::no_property> >, boost::no_property, boost::listS>&, int[((unsigned int)((int)V))][((unsigned int)((int)V))], boost::bgl_named_params<int*, boost::vertex_distance_t, boost::no_property>) " relevant variable declarations & typedefs are: typedef adjacency_list <setS, vecS, bidirectionalS, property <vertex_name_t, std::string>, \ property <edge_weight_t, int, property< edge_weight2_t, int > > > Graph; ..... // Graph g is constructed ..... int V = num_vertices(g); std::vector < int >d_j(V, (std::numeric_limits < int >::max)()); int D[V][V]; ..... // call Johnson's all pair shortest path algo. johnson_all_pairs_shortest_paths(g, D, distance_map(&d_j[0])); Do let me know if any more info is reqd. I would greatly appreciate any help/suggestions. Thanks and regards, Sangam =====-----=====-----===== Notice: The information contained in this e-mail message and/or attachments to it may contain confidential or privileged information. If you are not the intended recipient, any dissemination, use, review, distribution, printing or copying of the information contained in this e-mail message and/or attachments to it are strictly prohibited. If you have received this communication in error, please notify us by reply e-mail or telephone and immediately and permanently delete the message and any attachments. Thank you

1 0

Failed Linking against Filesystem
by Chris Miller 23 Nov '07

23 Nov '07

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Same problem, however, now I'm certain it's just not linking against the filesystem libraries in boost. I'm using EasyEclipse 3.3 CDT, and replaced the MinGW installation with the one from http://www.nuwen.net/, however, it still throws this error whenever I start to use the boost::filesystem API: src\AppLayer\DirectoryTree.o:c:/mingw/bin/../lib/gcc/i686-pc-mingw32/4.2.1-dw2/../../../../include/boost/filesystem/operations.hpp:289: undefined reference to boost::filesystem::detail::status_api(std::string const&, unsigned int&)' src\AppLayer\DirectoryTree.o:c:/mingw/bin/../lib/gcc/i686-pc-mingw32/4.2.1-dw2/../../../../include/boost/filesystem/operations.hpp:279: undefined reference to boost::filesystem::detail::status_api(std::string const&, unsigned int&)' src\AppLayer\DirectoryTree.o:c:/mingw/bin/../lib/gcc/i686-pc-mingw32/4.2.1-dw2/../../../../include/boost/filesystem/operations.hpp:503: undefined reference to boost::filesystem::detail::get_current_path_api(std::string&)' I'm fairly certain that I don't understand what's going on. The library files for the filesystem API are right in the lib\ directory, right where they should be. I think it might be that Eclipse isn't doing something correctly, however, I looked through the library paths in Eclipse and it looks to me as if everything is in order. Any help would be awesome, thanks in advance for any help you can offer! -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.7 (MingW32) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFHRTUMFjX73bUcQCERApWwAJ9D6auob+xmK9JVRr3rNVRgqPuf2wCghMh7 mxij+iLprZBZq6DmQkmflFw= =lvrF -----END PGP SIGNATURE-----

1 1

Boost.Test linker error - undefined reference to 'main'
by Justin Paul 22 Nov '07

22 Nov '07

Hi, I use the Boost library 1.34.1 on Ubuntu 7.10 (Gusty Gibbon). I get the following error while linking with libboost_unit_test_framework. user23@Mycomp:~/scrapbook$ g++ first.cpp -lboost_unit_test_framework /usr/lib/gcc/i486-linux-gnu/4.1.3/../../../../lib/crt1.o: In function `_start': (.text+0x18): undefined reference to `main' collect2: ld returned 1 exit status The first.cpp has the example given in the Boost website // Boost.Test #include <boost/test/unit_test.hpp> using boost::unit_test::test_suite; // most frequently you implement test cases as a free functions void free_test_function() { // reports 'error in "free_test_function": test 2 == 1 failed' BOOST_CHECK(2 == 1); // non-critical test => continue after failure int* p = (int*)0; *p = 0; } test_suite* init_unit_test_suite( int, char* [] ) { test_suite* test= BOOST_TEST_SUITE( "Unit test example 1" ); // this example will pass cause we know ahead of time number of expected failures test->add( BOOST_TEST_CASE( &free_test_function ), 1 /* expected one error */ ); return test; } // EOF Thanks in Advance. Justin

2 1

Visual Studio 2008
by John Dunn 22 Nov '07

22 Nov '07

Now that VS 2008 has been released via MSDN, I'm attempting to see if our app compiles and works using it. Following the instructions here ( http://thread.gmane.org/gmane.comp.lib.boost.user/27205/focus=27207 ) got boost compiled but the auto-link was still looking for vc80 in the library names. Adding the following to \boost\config\auto_link.hpp fixed the link issue #elif defined(BOOST_MSVC) && (BOOST_MSVC == 1400) // vc80: # define BOOST_LIB_TOOLSET "vc80" #elif defined(BOOST_MSVC) && (BOOST_MSVC >= 1500) // vc90: # define BOOST_LIB_TOOLSET "vc90" At this point everything appears to run. Is this the right way to start using boost in VS2008? At what point will boost 'properly' support VS2008? By properly I mean without me having to hack the boost src. Thanks- John

5 8

Boost.Extension
by NFarnsworth＠web.de 22 Nov '07

22 Nov '07

Hello, I want to use Boost.Extensions to dynamic load Libraries and create objects. My question is, is it also posible to use Boost.Extensions together with Boost.Singleton so that I can query singleton objects with the factoy of Boost.Extensions? Could you give me please some suggestions how I can achieve this requirement? Thanks for your help in advance and best regards Niklas _______________________________________________________________________ Jetzt neu! Schützen Sie Ihren PC mit McAfee und WEB.DE. 3 Monate kostenlos testen. http://www.pc-sicherheit.web.de/startseite/?mc=022220

1 0

date_time header-only icl 10.0 win32
by Hicham Mouline 22 Nov '07

22 Nov '07

hello, I intend to use boost/date_time. As a header-only lib. I normally don't need to link against any extra lib. By default, the intel compiler generates the following: 1>Linking... (Intel C++ Environment) 1>xilink: executing 'link' 1>LINK : fatal error LNK1104: cannot open file 'libboost_date_time-iw-mt-1_34_1.lib' It is the same problem as in http://lists.boost.org/Archives/boost/2004/08/70114.php which i don't see whether it was solved after all or not. I defined #define BOOST_ALL_NO_LIB and then it works fine. I'm really just wondering whether that thread was delayed or whether it should be restarted, rds,

2 1

[boost-users][regex] Failure with minimal example on GCC 4.3.1
by Darren Garvey 22 Nov '07

22 Nov '07

I'm not sure if I'm missing something here, but I think this is a bug. I'm trying to compile the following with gcc4.1.3 on Ubuntu 7.10: $ g++ -v Using built-in specs. Target: i486-linux-gnu Configured with: ../src/configure -v --enable-languages=c,c++,fortran,objc,obj-c++,treelang --prefix=/usr --enable-shared --with-system-zlib --libexecdir=/usr/lib --without-included-gettext --enable-threads=posix --enable-nls --with-gxx-include-dir=/usr/include/c++/4.1.3 --program-suffix=-4.1--enable-__cxa_atexit --enable-clocale=gnu --enable-libstdcxx-debug --enable-mpfr --enable-checking=release i486-linux-gnu Thread model: posix gcc version 4.1.3 20070929 (prerelease) (Ubuntu 4.1.2-16ubuntu2) #include <boost/regex.hpp> int main() { using namespace boost; std::string str; regex re("."); cmatch what; regex_match(str, what, re); return 0; } GCC doesn't manage to find the right overload of regex_match and says only this: lala.cpp: In function 'int main()': lala.cpp:11: error: no matching function for call to 'regex_match(std::string&, boost::cmatch&, boost::regex&)' /usr/local/src/boost/trunk/boost/regex/v4/regex_match.hpp:80: note: candidates are: bool boost::regex_match(const std::basic_string<charT, ST, SA>&, boost::match_results<typename std::basic_string<charT, ST, SA>::const_iterator, Allocator>&, const boost::basic_regex<charT, traits>&, boost::regex_constants::match_flag_type) [with ST = std::char_traits<char>, SA = std::allocator<char>, Allocator = std::allocator<boost::sub_match<const char*> >, charT = char, traits = boost::regex_traits<char, boost::cpp_regex_traits<char> >] It compiles fine if you instead pass str.c_str() as the first argument. On the other hand, If you explicitly qualify the regex types with boost::, gcc spews out the attached misery-ball. AFAIK, these all work on msvc9. Is the example above supposed to work? Cheers, Darren

3 3

serialization, iostreams and gzip compression to ostringstream
by John O-Connor 22 Nov '07

22 Nov '07

I have the following code serialising shared_ptr's to fstream and reading them back correctly. When I switch to using a stringstream (invert comments) I get a null value in "str" following serialisation. I noticed someone had a similar issue previously and solved it (but didn't explain how). Serialising/de-serialising between stringstream works fine when the iostreams are avoided. Could someone point out what I'm doing wrong please? Regards, John Using boost_1_33_1 on vc++2005 (8.0) // test.cpp : Defines the entry point for the console application. // #include "stdafx.h" #include <boost/archive/xml_oarchive.hpp> #include <boost/archive/xml_iarchive.hpp> /*//*/#include <fstream> //#include <sstream> #include <iostream> #include <boost/serialization/vector.hpp> #include <boost/serialization/shared_ptr.hpp> #include <boost/iostreams/filtering_stream.hpp> #include <boost/iostreams/filter/gzip.hpp> struct simple { simple() : i_(1){} simple(int i) : i_(i){} int i_; template<class Archive> void serialize(Archive & ar, const unsigned int version) { ar & BOOST_SERIALIZATION_NVP(i_); } }; int _tmain(int argc, _TCHAR* argv[]) { //std::string str; { boost::shared_ptr<simple> s(new simple(2)); std::vector<boost::shared_ptr<simple> > vec; for (int j = 0; j < 100; j++) { vec.push_back(s); } /*//*/std::ofstream os("c:/test_ser_shared_ptr.xml", std::ios_base::binary); //std::ostringstream os; boost::iostreams::filtering_ostream out; out.push(boost::iostreams::gzip_compressor()); out.push(os); boost::archive::xml_oarchive oa(out); oa & BOOST_SERIALIZATION_NVP(vec); //str = os.str(); } { std::vector<boost::shared_ptr<simple> > vec; /*//*/std::ifstream is("c:/test_ser_shared_ptr.xml", std::ios_base::binary); //std::istringstream is(str); boost::iostreams::filtering_istream in; in.push(boost::iostreams::gzip_decompressor()); in.push(is); boost::archive::xml_iarchive ia(in); ia & BOOST_SERIALIZATION_NVP(vec); int i = (*(vec.begin()))->i_; } return 0; } --- This e-mail may contain confidential and/or privileged information. If you are not the intended recipient (or have received this e-mail in error) please notify the sender immediately and delete this e-mail. Any unauthorized copying, disclosure or distribution of the material in this e-mail is strictly forbidden. Please refer to http://www.db.com/en/content/eu_disclosures.htm for additional EU corporate and regulatory disclosures.

1 0

Re: [Boost-users] [Statechart] How to decide between post_eventand process_eventatrun time ?
by Philippe DAVID 22 Nov '07

22 Nov '07

> > Yes, it is slightly more work than if there was a > state_machine::is_processing() > function. I'm just not sure whether your use case is sufficiently common to > justify adding such a function. Maybe you could provide more details > so that I > understand it better? Sure, I'll try. My state machine is coupled to a connection on which I must comply with some protocol. My layer is a middleware. Each time I have something interesting, like data or events, I call a user-supplied handler on a corresponding method from a react method of the state machine. If the user wants to close the connection I have the problem I described because: - either he decides to close the connection from a callback, which means the state machine is in the middle of processing the event which caused the call to the handler, then I must use post_event - or he decided to close the connection based on an event that didn't come from the connection, in that case I must use process_event. I simplified the problem but the idea is there. If my state machine calls a handler on which I don't have total control, and I supply a few methods that need to be processed using the state machine, then I need to decide between process and post_event. In the simple case I could also provide 2 close methods for the handler, one that must be called in callbacks and one for the other methods of handler. I don't think this is a clean way to solve this issue. Each method in my interface would have 2 versions, and the stability becomes really weak because calling the wrong method at the wrong place results in a crash. At this point, maybe my design is weak, and I shouldn't call the handlers callback directly from the react methods. Instead I could use an event queue to talk to the handler. In the react method I would post events to the queue, and make sure I dequeue it from outside the state machine. But it involves (much) more work... Hope my explanations are clear ;) What is your point of view on this ? Regards, Philippe

2 5