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Re: [Boost-users] How to get the port number and the address of a boost::asio::ip::tcp:acceptor object
by Jean-Sebastien Stoezel 07 Aug '08

07 Aug '08

Hi, The following code: boost::asio::ip::tcp::acceptor myacceptor(m_IoService); myacceptor.open(boost::asio::ip::tcp::v4()); boost::asio::ip::tcp::endpoint endpoint = myacceptor.local_endpoint(); generates the following exception: "An invalid argument was supplied" when myacceptor.local_endpoint() is invoked. any idea? On 8/7/08, Igor R <boost.lists(a)gmail.com> wrote: > > Then when I do: > > > > boost::asio::ip::tcp::acceptor acceptor(m_IoService); > > > > when I call > > > > boost::asio::ip::tcp::endpoint endpoint = acceptor.local_endpoint(); > > > > I get an exception as follow: > > "The file handle supplied is not valid" > > You have to open() the acceptor: > http://www.boost.org/doc/libs/1_35_0/doc/html/boost_asio/reference/basic_so… >

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about UTF8 to UNICODE
by Ken zhang 07 Aug '08

07 Aug '08

Hello I hava a UTF8 string reading from TinyXML, I want convert to a Unicode string (wchar_t) for some reasons, How can convert it by boost? Thanks Kenneth.Sh

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[Multi-index] how to create 1-n relation between multi index containers?
by Prometheus Prometheus 07 Aug '08

07 Aug '08

hi all a few weeks ago i came across multi index and now im using it very intensively in my linux application (using g++) the problem im facing more often is a situation like this: i have a structure using multi index for server's (for example) typedef struct server{ uint32_t ip,port; std::string hostname; }; and i have a groups structure typedef struct servergroup{ std::string groupname; uint32_t groupid; time_t sometimestamp; uint32_t groupstate; // std::vector<server> members; // << could this be a multi_index? }; what i need to do is create a relation between a group and it's members (servers) and thats what im not sure about how to achive using multi_index the reason for the relationship is that i need to create an index for queries like this: In which group is server X? or Which servers has Group X? The only possibility i see is by creating 1 structure which causes much memory overhead and updating is a bit of a problem, cause i would need a loop for updating the state of the group for every member, ... I also thought about using boost bimap, but im pretty unsure how? So anybody has a hint on this (including maybe a very small example)? im pretty sure its some kind of 'not see the wood for trees' problem thx for ur time _________________________________________________________________ Discover the new Windows Vista http://search.msn.com/results.aspx?q=windows+vista&mkt=en-US&form=QBRE

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boost tokenizer problem with stringstream
by Daryl Lilburn 07 Aug '08

07 Aug '08

Hi, A colleague has recently discovered a problem using tokenizerwith the output from a std::stringstream class in VC8. If we dothe following, we get an "ITERATOR LIST CORRUPTED" exceptionthrown: typedef boost::char_separator<char> Separators;typedef boost::tokenizer<Separators > Tokens; std::string str1("ABC");std::string str2("DEF");std::stringstream oss;oss << str1 << "," << str2; Tokens strList(oss.str(), Separators(",|"));Tokens::const_iterator strIter = strList.begin(); // exception thrown here I thought this might be because the string returned from oss.str() is temporaryso I tried the following change and it still failed: std::string tempStr(oss.str());Tokens strList(tempStr, Separators(",|"));Tokens::const_iterator strIter = strList.begin(); // exception thrown here Finally I tried this and it succeeded. std::string tempStr;oss >> tempStr;Tokens strList(tempStr, Separators(",|"));Tokens::const_iterator strIter = strList.begin(); // exception thrown here Can anyone tell me why the first two (in particular the second option) failed? RegardsDaryl Lilburn _________________________________________________________________ Are you paid what you're worth? Find out: SEEK Salary Centre http://a.ninemsn.com.au/b.aspx?URL=http%3A%2F%2Fninemsn%2Eseek%2Ecom%2Eau%2…

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[graph] Is there a way to stop BFS when a certain vertex was visited?
by Martin Mann 07 Aug '08

07 Aug '08

Hi, I am using BFS to find the shortest path between two nodes as suggested in the documentation for unweighted graphs (or all weights == 1). I have written a visitor and can now access a shortest path from the start vertex to the vertex of interest. ==================================================================== My question is: HOW to stop further BFS traversal of the graph? ==================================================================== Is there a possibility e.g. by emptying the vertex queue (e.g. by the visitor)? Or some other, more elegant way to do? Thanks in advance for your help, Martin

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[graph] Bug - add_edge (adjacency_list) does not report if edge already exists as stated in documentation
by Martin Mann 07 Aug '08

07 Aug '08

Hi, I encountered the following problem : a successive call with equal parameters u, v, and g of ============================================================ std::pair<edge_descriptor, bool> add_edge( vertex_descriptor u , vertex_descriptor v , adjacency_list& g ) ============================================================ yields both times "RESULT.second == true". But the documentation states, that only in case it is NOT PRESENT it should be true, which is obviously wrong for the second call. If I use the "edge(u,v,g)" method to check if the edge exists I get the correct result of "edge(u,v,g).second == false" before the first call and "edge(u,v,g).second == true" after the first and before the second call. So the problem is all about the add_edge function and I think it's more a bug than a feature. Because otherwise the bool-flag is obsolete or reports something totally different. Cheers, Martin ============================================================ The boost graph class I use ============================================================ //! The properties available for the nodes of a CoreGraph typedef boost::property< boost::vertex_index_t, size_t , boost::property< boost::vertex_name_t, std::string > > CoreGraph_NodeProperties; //! The properties available for the edges of a CoreGraph typedef boost::property< boost::edge_name_t, std::string > CoreGraph_EdgeProperties; //! The definition of a the internal graph representation typedef boost::adjacency_list< boost::vecS , boost::vecS , boost::undirectedS , CoreGraph_NodeProperties , CoreGraph_EdgeProperties > CoreGraph; ============================================================

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boost::function to member function - "changing the instance of the class".
by Alejandro Martinez 07 Aug '08

07 Aug '08

After i define a boost::function using bind to a member function of some signature... Can i change the instance to have as "this" in such function for another of the same type? Maybe pass it as a parameter at call time? Why would i want that? Imagine i have some class A that dispatches calls for a big amount of methods. The requests for such calls come serialized, and the method is selected by its name (string). So there should be a std::map<std::string, boost::function<some_signature> > to be able to make the actual call after i know what the name is without doing a switch or a huge ammount of ifs. So A has that map, and has it populated with member functions of itself. But i may have many instances of A. (actually, one for each of many threads). So having that map in each is a waste of resources. So maybe i could declare the map as static, so that it is shared between all instances of A. But to do that, i would need to be able to tell the function in the map im about to invoke, what its "this" should be at this time. Did i explain myself clearly? Thanks a lot for your time :)

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boost::asio non-blocking read
by Jean-Sebastien Stoezel 07 Aug '08

07 Aug '08

Hi, While I've been able to implement non-blocking reads on sockets, using boost::asio::read and boost::asio::socket_base::bytes_readable (only reading whern there's data available), I'm having troubles implementing non-blocking reads on serial_port stream object. Any idea how to do? Thanks! Jean

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[spirit] skip parser problem
by piotr270977＠interia.pl 07 Aug '08

07 Aug '08

Hi All I have a problem with spirit skip parser. If parsing text is ending with skiped char (ie. space) the parsing failed returning parse_info.full as false. For example, let's examine code from spirit documentation: http://spirit.sourceforge.net/distrib/spirit_1_8_5/libs/spirit/example/fund… If we parse string like that "B 6,4 ,6, 5" everything is OK, but if we parse "B 6,4 ,6, 5 " (with space at the end) parsing fail. How are you resolving this problem ??? ---------------------------------------------------------------------- Tylko dla detektywow! Konkurs na Smaker.pl Kliknij >>> http://link.interia.pl/f1eb1

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[proto] latest code and docs?
by Markus Werle 07 Aug '08

07 Aug '08

Hi! I am looking for the latest and greatest working version of proto and especially the proto docs in pdf and/or html. Where can I find it and when will it be included into boost? Btw.: Is there a canonical place where accepted libraries can be found *with generated docs*? Actually I have no svn access due to a firewall ... Thanks for any extra support. Markus

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