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Phoenix3 port to proto complete
by Thomas Heller 27 Jul '10

27 Jul '10

Ladies and Gentlemen, I proudly announce that the port of phoenix3 is completed! All testcases pass! (some with minor modifications) So, What is next? Here is my proposed schedule: - fix some minor issues - improve boost.bind compatibility: make all boost.bind testcases pass - implement all boost.lambda testcases and make them pass, as far as it is reasonable - add support for C++0x lambdas - make interoperability testcases for std::function, boost::function - adapt the documentation - clean up code (some parts are a little messy as of now) - improve compile time Did I miss something? This is a very tight schedule, I may not be able to finish all points during the GSoC period. Any help will be appreciated. Additionally a review of the current code is highly appreciated to point out some defects that might exist. The code can be checked out at: https://svn.boost.org/svn/boost/sandbox/SOC/2010/phoenix3 I will be happy to answer your questions! Additionally I would like to thank Joel de Guzman and Eric Niebler for their great assistance and initial designs! Best Regards, Thomas Heller

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query regarding mutex
by Abbhishek Misra 27 Jul '10

27 Jul '10

Hello All, This is how mutex class looks like #include <boost/thread/mutex.hpp> class mutex: boost::noncopyable { public: mutex(); ~mutex(); void lock(); bool try_lock(); void unlock(); typedef platform-specific-type native_handle_type; native_handle_type native_handle(); typedef unique_lock<mutex> scoped_lock; typedef unspecified-type scoped_try_lock; }; Please help me figure out what purpose does 'unspecified-type' serve below. typedef unspecified-type scoped_try_lock; as I understand typedef type_a name_a ; enables name_a to be used instead of type_a what does unspecified-type stand for ? and how does one use it ? regards Abhishek

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[Graph] Lazy BFS
by Belcourt, Kenneth 27 Jul '10

27 Jul '10

Hi, I'm looking to traverse a DAG using BFS where vertices are discovered after the last incident edge has been examined. That is, I want to discover vertices lazily rather than the current BFS behavior of discovering vertices eagerly (following the first incident edge). I know I can modify the BFS algorithm to effect this behavior but I'm wondering if anyone has figured out the visitor changes necessary to support this? Thanks. -- Noel

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boost MPI Signal: Segmentation fault (11)
by Jack Bryan 26 Jul '10

26 Jul '10

Dear All, I run a 6 parallel processes with boost MPI on a system with OpenMPI. When the run-time of the program is short, it works well. But, if the run-time is long, I got errors: [n124:45521] *** Process received signal ***[n124:45521] Signal: Segmentation fault (11)[n124:45521] Signal code: Address not mapped (1)[n124:45521] Failing at address: 0x44[n124:45521] [ 0] /lib64/libpthread.so.0 [0x3c50e0e4c0][n124:45521] [ 1] /lib64/libc.so.6(strlen+0x10) [0x3c50278d60][n124:45521] [ 2] /lib64/libc.so.6(_IO_vfprintf+0x4479) [0x3c50246b19][n124:45521] [ 3] /lib64/libc.so.6(_IO_printf+0x9a) [0x3c5024d3aa][n124:45521] [ 4] /home/path/exec [0x40ec9a][n124:45521] [ 5] /lib64/libc.so.6(__libc_start_main+0xf4) [0x3c5021d974][n124:45521] [ 6] /home/path/exec [0x401139][n124:45521] *** End of error message *** It seems that there may be some problems about memory management. But, I cannot find the reason. My program needs to write results to some files. If I open the files too many without closing them, I may get the above errors. But, I have removed the writing files from my program. The problem appears again when the program runs longer time. Any help is appreciated. Jack July 25 2010 _________________________________________________________________ The New Busy is not the too busy. Combine all your e-mail accounts with Hotmail. http://www.windowslive.com/campaign/thenewbusy?tile=multiaccount&ocid=PID28…

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Boost::interprocess::string problems
by this_thread 26 Jul '10

26 Jul '10

Good morning all! Many thanks in advance to anyone that can help me out with this matter. I've been doing some work with Boost::Interprocess shared memory lately, and finding it incredibly useful. I've successfully put interprocess mutexes (muti?) and vectors to work, but for whatever reason, I can't seem to get the hang of interprocess strings. I'm sure I'm just missing something stupidly obvious, and to a degree I already see it but don't know what the solution is. For a vector, I know I've got a create a new interprocess allocator which allocates whatever I want to store using the interprocess segment manager: typedef boost::interprocess::allocator<Foo, boost::interprocess::managed_shared_memory::segment_manager> FooAllocator; Then create a special vector which uses that allocator: typedef boost::interprocess::vector<Foo, FooAllocator> FooInterprocessVector; This works great, provided I remember to find<FooInterprocessVector> on the opposite process before accessing the vector during periods when it may have been modified. I can't seem to get the hang of strings though. I've looked around online and can't seem to find an example of how this should be set up, and I can't get it to accept an allocator. The only way I can seem to typedef one is something like: typedef boost::interprocess::string BoostString - or - typedef boost::interprocess::basic_string<char> BoostString; Using this, so long as I only write a short string to the shared memory, things work fine, but anything over a few characters quickly clobbers other data. Has anyone used Interprocess::Strings before and could possibly point me in the direction I'm going wrong? Thank you all! -- View this message in context: http://old.nabble.com/Boost%3A%3Ainterprocess%3A%3Astring-problems-tp292061… Sent from the Boost - Users mailing list archive at Nabble.com.

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base64 encoding ?
by Timothy Madden 26 Jul '10

26 Jul '10

Hello I keep looking in the online docs, and I can find old discussions on the issue, but I can not find the function for base64 encoding in boost. Can anyone please direct me to it ? Is it still there in boost ? Thank you, Timothy Madden

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boost basic_file open
by Afshin Amighi 26 Jul '10

26 Jul '10

Hello , I am very new in boost file system and simply I wrote a sample to use boost file system. I need a file descriptor for both read and write. When I implement below code for "sink" and "source" files, they work. But I don't understand why I couldn't open a basic_file object to read and write. Any comment is appreciated. Thanks in advance. void test_boost2(){ long long size=5*1024*1024; char buffer [L_tmpnam]; const char* prefix = "c1t"; string tempPath(archive::tmpdir()); filesystem::path path(tempPath); filesystem::space_info spi(space(path)); strcpy(buffer,prefix); if( spi.free > size * 3/2 && tmpnam (buffer+sizeof(prefix)-1) != NULL){ buffer[sizeof(prefix)-1]='_'; path/=buffer; boost::iostreams::basic_file<char> *tmpFile= new basic_file<char>(path.string()); tmpFile->open(path.string()); if(tmpFile->is_open()){ long long p=size-DATA_SIZE-2; tmpFile->seek(p,ios_base::beg); tmpFile->close(); } delete tmpFile; } }

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boost matching \b and match_not_null flag
by Gavrilov, Roman 26 Jul '10

26 Jul '10

Hello, I'm trying to find word boundaries with regex_search and "\b" pattern. I have the following code: string buff = "aaaa*******\\b"; boost::match_flag_type flags = boost::match_default | boost::match_not_null; boost::regex re("\\b"); boost::match_results<string::const_iterator> what; string::const_iterator start = buff.begin(); string::const_iterator end = buff.end(); if ( regex_search(start, end, what, re, flags)) { string out(start,what[0].second); cout << "match : " << out << endl; } I would expect it to print "aaaa" in out string and to match the second boundary, but in fact it didn't match anything. If I remove the match_not_null flag then it will match the first boundary at the beginning of the string as expected. I don't understand this behavior, am I missing something? Any help would be highly appreciated. Thanks, Roman

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[move] move emulation with bind?
by Tim Blechmann 26 Jul '10

26 Jul '10

hi all, i'm trying to make one of my classes movable. however i have some issues when using it with boost::bind: class my_movable_class; void my_function(my_movable_class const &); this doesn't compile: boost::bind(my_function, boost::move(my_movable_class)) the reason is, that the members of boost::rv are private ... is this my fault or an issue with the move emulation? thanks, tim -- tim(a)klingt.org http://tim.klingt.org Just what the hell is the experimental tradition? Morton Feldman

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[statechart] template state derived from simple_state compile error
by Nicolas Emiliani 26 Jul '10

26 Jul '10

Hi, I'm experiencing a compiling problem with boost.statechart. I created a template class called request<TCallBackType> derived from state_machine, and two template states called init<TCallBackType> and post<TCallBackType>, the idea is that request's initial states is init, and when recating to an event (initialize) it transits to post. The error i get is : sc_test.cpp: In member function ‘boost::statechart::result init<TCallBackType>::react(const initialize&)’: sc_test.cpp:38: error: expected primary-expression before ‘>’ token sc_test.cpp:38: error: expected primary-expression before ‘)’ token I'm pretty sure this has to be with the fact that the template method transit is here dependant of the template parameter, thus the compiler can't solve it, but I can't seem to figure it out. Tryed using typename but did not work. I'm using gcc (Ubuntu 4.4.3-4ubuntu5) 4.4.3 Any help will be aprecciated. Here's the code, there is a comment where the error occurs. #include <boost/statechart/event.hpp> #include <boost/statechart/state_machine.hpp> #include <boost/statechart/simple_state.hpp> #include <boost/statechart/state.hpp> #include <boost/statechart/transition.hpp> #include <boost/statechart/custom_reaction.hpp> #include <boost/mpl/list.hpp> namespace sc = boost::statechart; //FORWARD DECLARATION OF THE INITIAL STATE template<typename TCallBackType> struct init; template<typename TCallBackType> struct post; //STATE MACHINE template<typename TCallBackType> struct request : sc::state_machine<request<TCallBackType> , init<TCallBackType> > { TCallBackType call_backs; }; //EVENT struct initialize : sc::event<initialize> { }; //INITIAL STATE template<typename TCallBackType> struct init : sc::simple_state< init<TCallBackType>, request<TCallBackType> > { //reactions typedef boost::mpl::list< sc::custom_reaction<initialize> > reactions; //on initialize sc::result react(const initialize& e){ //HERE I GET THE COMPILING ERROR //IF I COMMENT THIS IT ALL GOES SMOOTHLY return this->transit< post<TCallBackType> > (); } typedef post<TCallBackType> p; }; //SECOND STATE template<typename TCallBackType> struct post : sc::simple_state< post<TCallBackType>, request<TCallBackType> > { //reactions typedef boost::mpl::list< sc::custom_reaction<initialize> > reactions; //on initialize sc::result react(const initialize& e){ return this->discard_event(); } }; int main(int argc, char* argv[]){ request<int> r; r.initiate(); return 0; } Nicolas Emiliani.

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