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Task groups using boost::thread
by gunnarnl 20 Mar '02

20 Mar '02

After overcoming my initial problems with compiling I have another question. I like very much the thread_group concept. My idea is to create different groups running different type of tasks. E.g. one group deals with user request tasks and another deal with responses from a mainframe etc. In addition, I think it would be good to be able to maximize the number of threads running concurrently in a single group. In this way one could tune the processes regarding to the number of CPUs and so that not one single group gets more CPU usage than others etc. I guess I'm not the first one to think about these things. Does anyone have any ideas about these type of task groups? Although it doesn't nearly contain what I want to do, I got the following test work nicely. #include <boost/thread/thread.hpp> #include <boost/thread/xtime.hpp> #include <iostream> #include <windows.h> template<class T> class thread_task { public: thread_task(T* obj) : m_obj(obj) { assert(m_obj != 0); } virtual ~thread_task() { } void operator() () { m_obj->setup(); m_obj->run(); m_obj->cleanup(); delete m_obj; } private: T* m_obj; }; class my_task { public: my_task() {} void setup() { std::cout << "setup " << GetCurrentThreadId() << std::endl; } void run() { std::cout << "Start sleeping in thread " << GetCurrentThreadId() << std::endl; boost::xtime xt; boost::xtime_get(&xt, boost::TIME_UTC); xt.sec += 1; boost::thread::sleep(xt); std::cout << "Woke up " << GetCurrentThreadId() << std::endl; } void cleanup() { std::cout << "cleanup " << GetCurrentThreadId() << std::endl; } }; int main(int argc, char* argv[]) { boost::thread_group threads; int i; for (i = 0; i < 10; ++i) { my_task* aTask = new my_task(); thread_task<my_task> new_task(aTask); threads.create_thread(new_task); } threads.join_all(); return 0; } By the way, is there an operation in boost::thread to get the current thread id?

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Problem linking boost::threads using MSVC6 SP4
by gunnarnl 20 Mar '02

20 Mar '02

I've created a windows console project with VC++ 6.0 and just used one of the examples in the documentation. I've also added the BOOST_HAS_THREADS macro in the settings. The program compiles well in debug mode but gives the following linking errors: Compiling... main.cpp Linking... msvcprtd.lib(MSVCP60D.dll) : error LNK2005: "public: virtual __thiscall std::runtime_error::~runtime_error(void)" (?? 1runtime_error@std@@UAE@XZ) already defined in main.obj msvcprtd.lib(MSVCP60D.dll) : error LNK2005: "public: __thiscall std::runtime_error::runtime_error(class runtime_error::runtime_error const &)" (??0runtime_error@std@@QAE@ABV01@@Z) already defined in main.obj msvcprtd.lib(MSVCP60D.dll) : error LNK2005: "public: __thiscall std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >::~basic_string<char,struct std::char_traits<char>,class std::allocator<char> >(void)" (??1? $basic_strin g@DU?$char_traits@D@std@@V?$allocator@D@2@@std@@QAE@XZ) already defined in main.obj msvcprtd.lib(MSVCP60D.dll) : error LNK2005: "public: __thiscall std::runtime_error::runtime_error(class runtime_error::basic_string<char,struct std::char_traits<char>,class std::allocator<char> > const &)" (??0runtime_error@std@@QAE@ABV? $basic_strin g@DU?$char_traits@D@std@@V?$allocator@D@2@@1@@Z) already defined in libcpmtd.lib(ios.obj) msvcprtd.lib(MSVCP60D.dll) : error LNK2005: "public: __thiscall std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >(char const *,class basic_ string<char,struct std::char_traits<char>,class std::allocator<char> >::allocator<char> const &)" (??0?$basic_string@DU? $char_traits@D@std@@V?$allocator@D@2@@std@@QAE@PBDABV? $allocator@D@1@@Z) already defined in main.obj LINK : warning LNK4098: defaultlib "MSVCRTD" conflicts with use of other libs; use /NODEFAULTLIB:library Debug/threads.exe : fatal error LNK1169: one or more multiply defined symbols found Error executing link.exe. Any help on this would be appreciated. Gunnar Olerud

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BFS-visitor with gcc3.0.1
by Wintermantel , Marc 20 Mar '02

20 Mar '02

Hello, I tried to complile the following code that worked under gcc 2.95.3 under gcc 3.0.1 and got tons of error messages: typedef adjacency_list< setS, vecS, undirectedS, property< vertex_color_t, default_color_type, property< vertex_degree_t, int, property< vertex_current_degree_t, int, property< vertex_priority_t, int > > > > > Graph; ... std::vector<graph_traits<Graph>::vertices_size_type> dist(num_vertices(G), 0); breadth_first_search (G, e, visitor ( make_bfs_visitor(record_distances(dist.begin(), on_tree_edge() ) ) ) ); ... The errors have something to deal with the visitors, more I could not read out of the errors. When I use a simple array in the form int d[n] it works. Yours truly, Marc Wintermantel Marc Wintermantel IMES - Structures Technology ETH Zurich, LEO C4 Leonhardstrasse 27 CH- 8092 Zurich Tel. ++41 1 633 35 32 Fax. ++41 1 632 17 02 [Non-text portions of this message have been removed]

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Still can't build boost on Linux with gcc 3.0.4
by Peter Simons 19 Mar '02

19 Mar '02

Hi, thanks to some helpful subscriber of this list, I figured out how to tell the Boost Build System where my Python is: I thus initiated the build by calling jam -sPYTHON_ROOT=/usr/local/python -sPYTHON_VERSION=2.2 \ -sBOOST_ROOT=/home/simons/projects/boost-current -sTOOLS=gcc but I am still getting lots of errors when trying to compile the latest version. A complete log of the failing build is available at http://cryp.to/boost-build-log.txt for anyone concerned. I'd appreciate any help on getting these errors fixed! -peter

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Request for reviewers for a book about Boost
by Björn Karlsson 18 Mar '02

18 Mar '02

Dear Boosters, I am currently working on "Beyond The C++ Standard Library - An Introduction to Boost", which is a tutorial-style book about several of the Boost libraries. Where would one seek knowledgeable reviewers? Of course, it is here, and that's the reason for this note. Before saying more, I would like to ask that responses be sent directly to me rather than to the list. The moderators have allowed this note, but this is not intended to become a discussion. Should I receive notes of public interest, I'll post those to the list. Also, for those that are subscribing to both Boost (developers) and Boost-Users, my apologies for cross-posting. Onwards! The book will cover the following libraries (minor modifications to this list may occur): * Any * Array * Bind * Call_traits * Compose * Concept check * Conversion * Functional * Operators * Random * Rational * Regex * Smart_ptr * Static_assert * Tokenizer * Tuple * Type_traits * Utility I am looking for people interested in reviewing one or more chapter(s) (libraries). If you are volunteering, please add information that states the library, or libraries, that you'd be willing to review. Where one reviewer will have a deep knowledge about the libraries, another may only have a strong interest. Both are very welcome! What's in it for you? Not money I'm afraid, but something that is hopefully more valuable: A chance to make the book better, to share some of your knowledge, and maybe to learn something new. Your name in the preface :-). To volunteer, send a comment or ask a question, please contact me directly at bjorn.karlsson(a)readsoft.com. Thanks! Before I end this post: Boost is becoming more and more important for the C++ community, and I would like to thank all participating Boosters for the libraries, the ideas, the research, the discussions and the enthusiasm that sums up to what we call Boost. All of this not only makes the world a better place, it also (which I personally think is more important) makes the world more interesting! Thanks, Bjorn Karlsson [Non-text portions of this message have been removed]

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Re: [Boost-Users] Re: Does filter_iterator work for maps?
by Rodrigo de Salvo Braz 17 Mar '02

17 Mar '02

-----Mensagem original----- De: Jeremy Siek <jsiek(a)cs.indiana.edu> >The above program compiles OK for me with g++ 2.95.2. What compiler are >you using? (there's a good chance the compiler error you are getting is a >bug in your compiler, not in your code or in the Boost code). Hi Jeremy, Thanks for the reply. Yes, I think it is the compiler too. I am using the Borland C++ Builder compiler 5.5 (the free command line compiler Borland made available a while ago). I am not sure yet I am not making a mistake, because I would expect this to be a popular compiler and simple things like this to have been found by now. All it takes to use the iterator adaptor libraries is including the header files, right? Thanks, Rodrigo _________________________________________________________ Do You Yahoo!? Get your free @yahoo.com address at http://mail.yahoo.com

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regex expression core dumps with \\
by soleani 17 Mar '02

17 Mar '02

Hi there, I've been using regex++ (v 3) for a while now. It's great! I just found out that my regex core dumps my program, look: std::string StringUtilities::getMsqlEscapedString( const char* input ) { if ( input == NULL ) return ""; cerr << "Hello" << endl; std::string inputStr( input ); cerr << "Hello111 (" << inputStr << ")" << endl; static const boost::regex expression1( "\\" ); cerr << "Hello222" << endl; string temp = boost::regex_merge( inputStr, expression1, "\\\\" ); cerr << "Hello33" << endl; static const boost::regex expression2( "'" ); return boost::regex_merge( temp, expression2, "\\'" ); } // StringUtilities::getMsqlEscapedString That's all I have. When I call it I see this: Testing getMsqlEscapedString... Hello Hello111 (hello) Aborted (core dumped) So, it seems that the call to: static const boost::regex expression1( "\\" ); makes it core dump. I went and changed that regular expression by "\"", just for kicks, and it works; it doesn't do what I want but it doesn't core dump. Anything I should do to avoid this problem? thanks, -Anibal

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Error with boost::regex library with Borland C++ Builder 6
by ynaig2k 17 Mar '02

17 Mar '02

Hi, I tried everything to understand why I get the error "Abnormal program termination" in the second run of the function with the following code: void function() { regex e( std::string(Edit1->Text.c_str()) ); cmatch what; string response; TFileStream* file = new TFileStream( "1.htm", fmOpenRead ); response.resize(file->Size+1); file->Read(response.begin(), file->Size); response[file->Size] = 0; delete file; std::string::const_iterator start; start = response.begin(); while( regex_search( start, what, e ) ) { for ( unsigned int i = 0 ; i < what.size() ; i++ ) { { std::string result = std::string(what[i].first, what[i].second); Memo1->Lines->Add( result.c_str() ); } Memo1->Lines->Add(""); start = what[0].second; } } Thanks

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Re: [Boost-Users] Re: Does filter_iterator work for maps?
by Rodrigo de Salvo Braz 16 Mar '02

16 Mar '02

-----Mensagem original----- De: Jon Kalb <kalb(a)LibertySoft.com> Para: Boost-Users(a)yahoogroups.com <Boost-Users(a)yahoogroups.com> Data: Sexta-feira, Março 15, 2002 09:01 Assunto: Re: [Boost-Users] Re: Does filter_iterator work for maps? On 3/15/02 4:37 PM, "rodrigo_braz" <rodrigo_braz(a)yahoo.com> wrote: >> Actually my main problem with this iterator is in the code below: >CodeWarrior doesn't complain about this code, but I think that it should be: As Jeremy pointed out, that doesn't work. It sounds like it is a compiler issue (I am using Borland). I will go back to the boost pages to see if there is anything I can do about it. Thanks, Rodrigo _________________________________________________________ Do You Yahoo!? Get your free @yahoo.com address at http://mail.yahoo.com

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Does filter_iterator work for maps?
by rodrigo_braz 16 Mar '02

16 Mar '02

Hi, I don't see a reason for filter_iterator not to work with map iterators. However, the program below doesn't work. I get a compiler error "Cannot generate template specialization from 'make_filter_iterator<Predicate,Iterator> (Iterator,Iterator,const Predicate &)' in function main()" Any ideas? Thanks, Rodrigo #include <map> #include <ostream> #include "boost/iterator_adaptors.hpp" #include <algorithm> using namespace std; using namespace boost; struct pair_is_active { bool operator()(const pair<const size_t,float>& p) { return 0 < p.second; } }; ostream& operator<<(ostream& o, pair<const size_t, float> p) { return o << "(" << p.first << ", " << p.second << ")"; } int main() { map<size_t,float> m; m[0] = 10; m[1] = 15; m[2] = 0; m[3] = 13; copy(boost::make_filter_iterator<pair_is_active>(m.begin, m.end()), boost::make_filter_iterator<pair_is_active>(m.end(), m.end()), ostream_iterator<pair<const size_t,float> >(cout,",")); return 0; }

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boost newbie questions
by Harm de Laat 15 Mar '02

15 Mar '02

Hi all, I'm new to Boost and relativily new to C++. I'm trying to program threads on my Redhat 7.2 linux. I have the following code: #include <iostream> #include <boost/thread/thread.hpp> #include <boost/thread/xtime.hpp> struct thread_struct { thread_struct(int secs) : m_secs(secs) {} void operator ()() { boost::xtime xt; boost::xtime_get(&xt, boost::TIME_UTC); xt.sec += m_secs; boost::thread::sleep(xt); std::cout << "Boosted!!!" << std::endl; } int m_secs; }; int main (int argc, char* argv[]) { int secs = 5; std::cout << "Starting..." << std::endl; thread_struct ts(secs); boost::thread thrd(ts); thrd.join(); } The code compiles without any problems... But do I have link it against some library? Because I cannot link it to an executable file. I'm new to this. So can somebody please be so kind to help me and describe the steps nessecary to run this Thread example file... Many Thanks, Harm de Laat Informatiefabriek The Netherlands

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Error with boost::regex library in Borland C++ Builder 6
by Giany2k 14 Mar '02

14 Mar '02

Hi, Can anyone explain to me why I get "Abnormal program termination" at the exit of the function shown below in the example. The error occurs when exiting the function after it was called second time. //---------------------------------------------------------------------- ----- #include <vcl.h> #pragma hdrstop #include <boost/regex.hpp> #include <string> #include "Unit1.h" //---------------------------------------------------------------------- ----- #pragma package(smart_init) #pragma resource "*.dfm" TForm1 *Form1; //---------------------------------------------------------------------- ----- __fastcall TForm1::TForm1(TComponent* Owner) : TForm(Owner) { Edit1->Clear(); } //---------------------------------------------------------------------- ----- using namespace boost; using namespace std; void __fastcall TForm1::Button1Click(TObject *Sender) { Memo1->Clear(); if ( Edit1->Text.IsEmpty() ) return; regex e( std::string(Edit1->Text.c_str()) ); cmatch what; string response; TFileStream* file = new TFileStream( "1.htm", fmOpenRead ); response.resize(file->Size+1); file->Read(response.begin(), file->Size); response[file->Size] = 0; delete file; std::string::const_iterator start; start = response.begin(); while( regex_search( start, what, e ) ) { for ( unsigned int i = 0 ; i < what.size() ; i++ ) { std::string result = std::string(what[i].first, what[i].second); Memo1->Lines->Add( result.c_str() ); } Memo1->Lines->Add(""); start = what[0].second; } } //---------------------------------------------------------------------- -----

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Build problems on Linux with gcc 3.0.4
by Peter Simons 13 Mar '02

13 Mar '02

Hi, I have tried to build the current boost library as checked-out of the CVS repository, but I failed miserably. For one, the build process failed to recogize that Python is installed in /usr/local/python rather than /usr/local. As a result, it didn't find the python-specific include files either. I tried to set the appropriate environment variables but failed. So I added the directory /usr/local/python/include/python2.2 to CPLUS_INCLUDE_PATH and then it worked -- at least a little better than before. Once the Python includes were found, the build process progressed to actually linking some programs: gcc-Link-action status/bin/config_test.test/gcc/debug/runtime-link-dynamic/threading-multi/config_test status/bin/config_test.test/gcc/debug/runtime-link-dynamic/threading-multi/config_test.o: In function `boost_has_clock_gettime::f()': /home/simons/projects/boost-current/libs/config/test/boost_has_clock_gettime.cxx:19: undefined reference to `clock_gettime' collect2: ld returned 1 exit status Another failure was: ...failed gcc-Link-action status/bin/config_test.test/gcc/release/runtime-link-dynamic/threading-multi/config_test ... gcc-C++-action status/bin/class_concept_fail_expected.test/gcc/debug/runtime-link-dynamic/class_concept_fail_expected.o /home/simons/projects/boost-current/boost/concept_check.hpp: In member function `void boost::EqualityComparableConcept<TT>::constraints() [with TT = foo]': /home/simons/projects/boost-current/libs/concept_check/class_concept_fail_expected.cpp:25: instantiated from here /home/simons/projects/boost-current/boost/concept_check.hpp:265: no match for `foo& == foo&' operator /home/simons/projects/boost-current/boost/concept_check.hpp:266: no match for `foo& != foo&' operator Plenty of files failed to compile or to link, but I don't want to flood the list with error messages. So, first of all, is there any "right" way to tell the build process where python is installed? Maybe I should start from the scratch from there. -peter

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Jam: Building libraries that use the static runtime library
by Dale Peakall 13 Mar '02

13 Mar '02

I need to build libraries that link against the static runtime library: I tried the following Jam invocation: jam -sBOOST_ROOT=. -sTOOLS="msvc-stlport" -sBUILD="debug release <runtime-link>static" But jam balks and reports: Error: <libs!python!build>libboost_python_static: target requirements conflict for requested build { <runtime-link>dynamic <target-type>LIB <runtime-link>static } Help! So, I've obviously got it wrong (btw I'm not interested in building python library just threads and regex). TIA. - Dale.

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AIX and Boost 1.27.0 (Does not compile)
by samsrd 12 Mar '02

12 Mar '02

Has anyone tried to compile Boost 1.27.0 (or any version for that matter) on IBM AIX using the xlC compiler (IBM Visual Age). There are many compile errors (usually template related) along the lines of: "../../../../ThirdParty/boost/regex/detail/regex_cstring.hpp", line 77.40: 1540- 0152 (W) A template dependent name that is a type must be qualified with "typena me". "../../../../ThirdParty/boost/regex.hpp", line 528.55: 1540-0152 (W) A template dependent name that is a type must be qualified with "typename". "../../../../ThirdParty/boost/regex.hpp", line 532.13: 1540-1628 (S) Every templ ate parameter for a constructor template must be used in the parameter list of t he constructor. "../../../../ThirdParty/boost/regex.hpp", line 532.34: 1540-0152 (W) A template dependent name that is a type must be qualified with "typename". "../../../../ThirdParty/boost/regex.hpp", line 744.13: 1540-0152 (W) A template dependent name that is a type must be qualified with "typename". "../../../../ThirdParty/boost/regex.hpp", line 938.4: 1540-0152 (W) A template d ependent name that is a type must be qualified with "typename". "../../../../ThirdParty/boost/regex.hpp", line 438.27: 1540-0130 (S) "def_alloc_ param_traits" is not declared. "../../../../ThirdParty/boost/regex.hpp", line 1414.1: 1540-0062 (S) The incompl ete class "match_results" must not be used as a qualifier. "../../../../ThirdParty/boost/regex.hpp", line 1455.35: 1540-0140 (S) The text " &" is unexpected. "match_results" may be undeclared, ambiguous or may require " typename" qualification. "../../../../ThirdParty/boost/regex.hpp", line 444.7: 1540-1303 (I) "template cl ass match_results" is not visible. @

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thread::yield() vs Sleep()ing
by simonwlb 10 Mar '02

10 Mar '02

I'm using thread::yield() in my multi-threaded cross-platform application to avoid "CPU burn". This is because I have threads that are in an infinte loop in order to do some polling. There are no mutexes to wait on in the loop. void X::threadFunction() { for(;;) { if( m_x->isReady() ) doSomething(); . . . boost::thread::yield(); } } If the answer is "you should almost never poll like that - try to use mutexes etc. as much as possible" please say so (I'm a newbie to threads)! In any case, if I choose to have a thread in an infinite loop anyway, I have three options (assuming I have no mutexes available to me): 1. Don't yield or Sleep at all. 2. Sleep for a while - say for example, 10 ms. 3. Yield. Option 1 is clearly wrong. The CPU usage will go to 100% and the whole machine may slow down to an unusable speed. Option 2 works well in my emperical tests. The thread loop executes plenty fast enough and my Windows CPU meter shows virtually 0% CPU usage. 10ms is a bit of an arbitrary figure though - My code needs to work on a variety of software and hardware platforms, so the ideal number is hard or impossible to know. Option 3 also works well in my emperical tests and seems like the neat solution (no arbitrary waiting period). My application and the system as a whole both run smoothly and fast. The only irksome thing is that the CPU meter shows 100% usage. That's a bit alarming for me and the users of my software. My questions: 1. Should thread loops without logical wait conditions be avoided as much as possible? Is that the problem? 2. Should I just yield() or should I pause for a time period? 3. How do you select a time period to wait? Simon Bailey

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Boost Building
by karl_m_au 09 Mar '02

09 Mar '02

Hiya I'm trying to build boost 1.27.0 on a Debian linux system. I've built the boost version of jam. Both g++ 2.95.3 and g++ 3.0.3 are installed. I'm pretty sure I've made the appropriate changes to get g++ 3.0 to be used in the build process. I've used various versions of the command line recommended in the documentation. Very few of the builds work, becuse of this: g++-3.0 -c -Wall -ftemplate-depth-100 -I"libs/regex/build" -o "libs/regex/build/bin/libboost_regex.a/gcc-3/debug/c_regex_traits.o" "libs/regex/build/../src/c_regex_traits.cpp" Somehow the <include> directive isn't working. Any clues? TIA Karl M

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Boost python
by andrewperella 08 Mar '02

08 Mar '02

I am having great trouble with boost python whenever I do anything slightly more compilcated than the examples. I have a wrapped a Vector3 class with 3 floats x,y,z. In python: a=m2.Vector3(1,2,3) a.x 1.0 a.x=100 a.x 100.0 This is correct - ie I can disply and modify a.x Unfortunatedly if wrap another class - Camera which contains a member variable : Vector3 pos then I cannot set camera.pos.x Looking in the debugger, I seem to be getting a copy (in fact sometime 3 or more copy constructors are called) of pos and I am modifying this temporary copy! Help. Surely I can wrap no pointer member variables? Regards, Andrew

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1.27 BGL and VC++7.0 compilation problem
by elgatomoses 07 Mar '02

07 Mar '02

I am having trouble compiling the Graph library with VC++7.0 (.NET) - I'm getting "INTERNAL_COMPILER_ERROR". The problem has to do with the is_array definition in composite_traits.hpp. Has anyone else encountered this problem - perhaps there are some compiler switches that I can set... TIA Mark Kruger

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Boost.build question: Adding a new unit-test rule
by Helge Penne 04 Mar '02

04 Mar '02

Hi. I'm working on a project where some of the unit test are very inconvenient to implement with CppUnit and Mock classes or stubs alone, but would be very simple to implement by having them print messages to standard output, pipe this to a log file and diff this against a reference file. I added the following to our Jamrules file (most of it is stolen from the standard unit-test rule and run action): rule unit-test-diff { local files = [ exe $(<) : $(2) : $(3) : $(4) : EXE ] ; type-DEPENDS test : $(files) ; local file ; for file in $(files) { run-and-diff $(file) ; } } actions run-and-diff { $(SHELL_SET)PATH=$(RUN_PATH) $(SHELL_EXPORT)PATH $(<) > $(<:D=:S=.log) diff $(<:S=.log) $(<:S=.ref) # diff $(<:D=:S=.log) $(<:D=:S=.ref) } This runs the unit test program, pipes the output to <targetname>.log and diffs agains <targetname>.ref. There is only one problem: I cannot get Boost.build to locate these files in the correct folder. The Jamfile for the unit test is located in the same folder as the unit test source code. This is the only natural place for the ref-file as well. The action above has three different alternatives for the actual diff operation. The first uses the full path of the executable, but replaces the last part of the file name with .log and .ref. This places them in the binary folder of the unit test program, which isn't not very convenient. The second strips away the path, but since the currect folder always is the project root (not the folder where the Jamfile is), this places the log and ref files on the project root, which is almost as bad as the first alternative. I also experimented briefly with :G but this has no effect as the file path did not seem to contain grist. One possible solution might be to add a path feature to the target and set this to the reference file name, but I'm not quite sure how to implement this for rules that are not part of a tools.jam-file I really need the unit test rule to place these files in the folder where the rest of the test source code is. Does anyone know how to do this? - Helge Penne

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(no subject)
by Hook.RobertA(CC) 04 Mar '02

04 Mar '02

I put the following up at source forge support, then realised that doesn't seem to be likely to get a response.... I would have put this through the yahoo group, but I'm stuck behind a mind-bogglingly repressive firewall. SO I'll scream for help here, bearing in mind the dictum that in cyberspace no-one can hear you scream. I have download 1.27.0, and am attempting to build and use Boost under HP-UX 11.00. There are two problems, and I cannot tell if they are related or not. Firstly, the install instructions along the lines of jam -sBOOST_ROOT=. -=sTOOLS="hpux" simply produce the following (after I bodgied up a hpux-tools.jam) +: line 1304: yacc stack overflow at keyword } don't know how to make all ...found 1 target... ...can't find 1 target... after smacking my head on the desk for several days, I've given up on that one and attempted to build boost_1_27_0/libs/tuple/test/io_test.cpp using aCC -c +z +p $APP_INCLUDE -o io_test.o io_test.cpp (where APP_INCLUDE is -I <yada/yada/yada> as appropriate) which results in "tuple_basic.hpp", line 290 # Cannot generate a specialization of incomplete template struct STATIC_ASSERTION_FAILURE<(bool)0>. BOOST_STATIC_ASSERT(length<cons>::value == 2); // check length = and errors cascading after that. Looking at various messages and comments, I believe that someone somewhere has managed to get boost working under HP-UX, but I'm dammned if I can. Help! Oh yes, by the way, I'm stuck behind a repressive firewall and cannot even *read* the message archive at Yahoo, let alone subscribe / post! (Puts head down on desk and begins sobbing quietly) -- Robert Hook - DCC Analyst/Programmer Polaris Group, Information Systems Branch Queensland Police Service Hook.RobertA(a)police.qld.gov.au PH: 07 3364 3807 ********************************************************************** This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify securityscanner(a)police.qld.gov.au. This footnote also confirms that this email message has been checked for the presence of computer viruses. **********************************************************************

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[Fwd: compile time container type identification]
by hicks 01 Mar '02

01 Mar '02

Hello I need to identify if a container is of a certain type. Specifically, from inside the code for container template <class T> Cont, I want to identity if T is itself of type Cont<U> for some U. (The type of U does not matter.) I couldn't see anything in *_traits.hpp that looks applicable. Any advice or references would be appreciated. Craig Hicks KGK Tokyo [Non-text portions of this message have been removed]

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RE: [Boost-Users] Linking an Archive
by Tom Matelich 27 Feb '02

27 Feb '02

The first getting_started1.so contains all the symbols from all of the objects linked into it. The second one only contains the symbols from getting_started.o and the symbols from libboost_python.a which satisfy unsatified symbols of getting_started1.o. Linking shared library is like linking an executable, it only takes the symbols from archives that it needs to satisfy itself. The first question is why you want libboost_python.a. If it is a valid reason, then you need to find a way to get all the code you need out of it into the shared lib. The first would be to use ar to get all the objects out, then take those and put them into the shared library. The second would be to keep adding unsatified symbols to getting_started.o until getting_started1.so has everything it needs. Tom > -----Original Message----- > From: doak87508 [mailto:jdoak@lanl.gov] > Sent: Wednesday, February 27, 2002 10:21 AM > To: Boost-Users(a)yahoogroups.com > Subject: [Boost-Users] Linking an Archive > > > I am playing around with using an archive to created a shared library > (.so file) instead of linking all the individual objects. I have > success when I link individual objects: > > % g++ -shared classes.o conversions.o errors.o extension_class.o > functions.o init_function.o module_builder.o objects.o types.o > cross_module.o getting_started1.o -o getting_started1.so > > % python > 1;31mh[1] >>> import getting_started1 > 1;31mh[1] >>> getting_started1.greet() > 'hello, world' > > Now, I create an archive: > > % ar r libboost_python.a classes.o conversions.o errors.o > extension_class.o functions.o init_function.o module_builder.o > objects.o types.o cross_module.o > > Then, I link that archive into the shared library: > > % g++ -shared libboost_python.a getting_started1.o -o > getting_started1.so > > % python > 1;31mh[1] >>> import getting_started1.so > Traceback (most recent call last): > File "<stdin>", line 1, in ? > ImportError: ./getting_started1.so: undefined symbol: > add__Q35boost6python19module_builder_basePQ45boost > 6python6detail8functionPCc > > I have also tried linking as follows with no change in result: > > % g++ -shared -L. -lboost_python getting_started1.o -o > getting_started1.so > > Does someone know how to get linking working with an archive file? > > JD > > > > Info: <http://www.boost.org> > Wiki: <http://www.crystalclearsoftware.com/cgi-bin/boost_wiki/wiki.pl> > Unsubscribe: <mailto:boost-users-unsubscribe@yahoogroups.com> > > > Your use of Yahoo! Groups is subject to > http://docs.yahoo.com/info/terms/ > >

2 1

in-place set_union/difference/etc ...
by ivan_dobrianov 27 Feb '02

27 Feb '02

Does anyone know of any existing standard tool [an insert iteartor or something equivalent] that can allow one to perform union, difference, etc on sets and maps in-place. E.g. instead of using set<MyClass> s1, s2, temp; set_union( s1.begin(), s1.end(), s2.begin(), s2.end(), inserter(temp, temp.begin())); temp.swap(s2); i'd like to do, say: copy(s1.begin(), s1.end(), my_unioner(s2, s2.begin())); which will do s2 = s1 + s2 in LINEAR time. It's pretty simple to write an inserter like that, but I am just wondering if there is one already ... or something similar. Thanks!

1 0

Bug in boost_1_27_0.tar.gz threads library
by Martin Brown 27 Feb '02

27 Feb '02

Hi There seems to be a missing '}' in libs/thread/src/once.cpp when compiling on gcc-3.04 on Redhat Linux 6.2. I added one and it seems to work. Not sure if it is in the right place. Context diff: *** once.cpp Thu Feb 7 15:33:15 2002 --- once.cpp.new Wed Feb 27 15:53:02 2002 *************** *** 55,62 **** --- 55,63 ---- { once_callback* cb = reinterpret_cast<once_callback*>(pthread_getspecific(key)); (**cb)(); } + } #elif defined(BOOST_HAS_MPTASKS) void *remote_call_proxy(void *pData) { std::pair<void (*)(), boost::once_flag *> &rData(*reinterpret_cast<std::pair<void (*)(), boost::once_flag *> *>(pData)); Thanks for some great libraries! Martin __________________________________________________ Do You Yahoo!? Everything you'll ever need on one web page from News and Sport to Email and Music Charts http://uk.my.yahoo.com

2 1

Linking an Archive
by doak87508 27 Feb '02

27 Feb '02

I am playing around with using an archive to created a shared library (.so file) instead of linking all the individual objects. I have success when I link individual objects: % g++ -shared classes.o conversions.o errors.o extension_class.o functions.o init_function.o module_builder.o objects.o types.o cross_module.o getting_started1.o -o getting_started1.so % python 1;31mh[1] >>> import getting_started1 1;31mh[1] >>> getting_started1.greet() 'hello, world' Now, I create an archive: % ar r libboost_python.a classes.o conversions.o errors.o extension_class.o functions.o init_function.o module_builder.o objects.o types.o cross_module.o Then, I link that archive into the shared library: % g++ -shared libboost_python.a getting_started1.o -o getting_started1.so % python 1;31mh[1] >>> import getting_started1.so Traceback (most recent call last): File "<stdin>", line 1, in ? ImportError: ./getting_started1.so: undefined symbol: add__Q35boost6python19module_builder_basePQ45boost 6python6detail8functionPCc I have also tried linking as follows with no change in result: % g++ -shared -L. -lboost_python getting_started1.o -o getting_started1.so Does someone know how to get linking working with an archive file? JD

1 0

autoconf+make
by josefsyk 26 Feb '02

26 Feb '02

I've been struggling to port parts of the boost libraries to Linux using gnu's automake, just to hit the wall every time. Anyone out there who has done this already? The files needed are: boost/smart_ptr.hpp boost/pending/ct_if.hpp boost/random.hpp boost/bind.hpp boost/function.hpp Would be nice to have the Makefile.am for BGL too. cheers.

2 1

boost::condition question
by svanechel 26 Feb '02

26 Feb '02

Hi, I'm trying to create a mechanism that synchronizes access to shared data on a per-operation basis. The idea is that some operations (E.g. read operations) can proceed concurrently, while others (write operations) must block all other threads. I thought boost::condition would do the trick. Since I do not have that much experience in multithreaded programming it is entirely possible that I do not fully understand boost::condition or its allowable usage. I tried to put operations in an "Operation Group". All operations belonging to the same group are allowed to execute concurrently, while all others are blocked (E.g. all read operations are in the same group). It is also possible that an operation doesn't specify an Operation Group, in which case a temporary group is assigned to the operation for each thread that calls it. Write operations are constructed this way. Below is an example of what I mean (OperationLevelLockable is defined below): class SomeClass : private OperationLevelLockable { public: int ReadData() { Lock lock( this, READ_OP_GROUP ); return ( mData ); } void WriteData( int data ) { Lock lock( this ); // assign temp group to operation, // so each write // operation blocks all other accesses mData = data; } private: int mData; }; I'm developing on Windows 2000 on a multiprocessor machine. This is the code I use to test my idea: const int32 OPERATION_GROUP_1 = 1; const int32 OPERATION_GROUP_2 = 2; const int NUM_THREADS = 4; class TestOperationLevelLockable : public MTTestCase { public: TestOperationLevelLockable() : mShared( this ), mCurrentGroup( 0 ), mThreadCount( 0 ) { // Create two sets of threads, each performing a // different operation // When the TestOperationLevelLockable object is // constructed all // registered threads are created an start running RegisterThread( this, &TestOperationLevelLockable::Operation1Thread, NUM_THREADS ); RegisterThread( this, &TestOperationLevelLockable::Operation2Thread, NUM_THREADS ); } void CallFromGroup( int32 opGroup ) { boost::mutex::scoped_lock lock( mMutex ); if ( 0 == mCurrentGroup ) { mCurrentGroup = opGroup; } if ( ( mCurrentGroup != opGroup ) && ( mThreadCount < NUM_THREADS ) ) { ReportFailure( "OperationLevelLockable failed to lock out operations of different group", __FILE__, __LINE__ ); } ++mThreadCount; } protected: class MTObject : public OperationLevelLockable { public: MTObject( TestOperationLevelLockable* target ) : mTarget( target ) {} void CallFromGroup( int32 opGroup ) { mTarget->CallFromGroup( opGroup ); } private: TestOperationLevelLockable* mTarget; }; MTObject mShared; int32 mCurrentGroup; int mThreadCount; boost::mutex mMutex; void DoMTTest() { } void Operation1Thread() { MTObject::Lock lock( mShared, OPERATION_GROUP_1 ); mShared.CallFromGroup( OPERATION_GROUP_1 ); SleepThread( 30 ); // seconds, to keep the thread busy } void Operation2Thread() { MTObject::Lock lock( mShared, OPERATION_GROUP_2 ); mShared.CallFromGroup( OPERATION_GROUP_2 ); SleepThread( 30 ); // seconds, to keep the thread busy } }; And here is OperationLevelLockable: class OperationLevelLockable { class AccessCounter; public: OperationLevelLockable(){} typedef Internal::DefaultTMIntType IntType; template<typename T> struct MakeSharedType { typedef T volatile Type; }; class Lock; friend class Lock; class Lock { public: Lock( OperationLevelLockable& obj ) : mCounter( obj.mOpAccessCounter ) { mCounter.EnterOperation( Lock::TempOpGroup() ); } Lock( OperationLevelLockable& obj, int32 opGroup ) : mCounter( obj.mOpAccessCounter ) { mCounter.EnterOperation( opGroup ); } ~Lock() { mCounter.LeaveOperation(); } private: Lock( Lock const& ); Lock& operator=( Lock const& ); static IntType TempOpGroup() { static volatile IntType opGroup = Internal::kFIRST_AUTO_GROUP; IntType newGroup = OperationLevelLockable::AtomicIncrement( opGroup ); if ( newGroup >= Internal::kLAST_AUTO_GROUP ) { OperationLevelLockable::AtomicAssign( opGroup, Internal::kFIRST_AUTO_GROUP ); } return ( newGroup ); } AccessCounter& mCounter; }; static inline IntType AtomicIncrement( volatile IntType& lval ); static inline IntType AtomicDecrement( volatile IntType& lval ); static inline void AtomicAssign( IntType& lval, IntType rVal ); static inline void AtomicAssign( volatile IntType& lval, IntType rVal ); private: class AccessCounter : private boost::base_from_member<boost::recursive_mutex> { public: AccessCounter() : mLock( member ), mRefCnt( 0 ), mOpGroup( Internal::kANY_GROUP ) {} bool IsOpGroupActive( IntType opGroup ) const { return ( ( Internal::kANY_GROUP == mOpGroup ) || ( opGroup == mOpGroup ) ); } void LeaveOperation() { if ( 0 == OperationLevelLockable::AtomicDecrement( mRefCnt ) ) { SetOpGroup( Internal::kANY_GROUP ); mCanOpProceed.notify_all(); } } void EnterOperation( IntType opGroup ) { mCanOpProceed.wait( mLock, CanOpProceed( *this, opGroup ) ); SetOpGroup( opGroup ); OperationLevelLockable::AtomicIncrement( mRefCnt ); } private: AccessCounter( AccessCounter const& ); AccessCounter& operator=( AccessCounter const& ); struct CanOpProceed { CanOpProceed( AccessCounter const& counter, IntType opGroup ) : mOpGroup( opGroup ), mCounter( counter ) {} bool operator()() const { return ( mCounter.IsOpGroupActive( mOpGroup ) ); } private: CanOpProceed& operator=( CanOpProceed const& ); int32 mOpGroup; AccessCounter const& mCounter; }; void SetOpGroup( IntType opGroup ) { OperationLevelLockable::AtomicAssign( mOpGroup, opGroup ); } boost::recursive_mutex::scoped_lock mLock; boost::condition mCanOpProceed; volatile IntType mRefCnt; volatile IntType mOpGroup; }; OperationLevelLockable( OperationLevelLockable const& ); OperationLevelLockable& operator=( OperationLevelLockable const& ); AccessCounter mOpAccessCounter; }; The idea is that the first operation that is executed acquires the lock and blocks out all threads not belonging to the same Operation Group. The original blocking works fine. Only threads executing in the same Operation Group are allowed to continue. When the last thread of the group leaves the operation in OperationLevelLockable::AccessCounter::LeaveOperation it releases all waiting threads and a thread from the other group is allowed to run. However when this thread finishes no new threads are allowed to run anymore and the application hangs. Am I using boost::condition incorrectly. Should I use something else? It the test code wrong? Are there any other errors in the code that prevent it from behaving as expected. Should I use another technique to achieve the same? I hope there is someone out there who has the hart to read through the entire posting and help me. I hope I have given enough information. Thx. Sven Van Echelpoel.

2 4

Building regex with msvc6sp5 and stlport
by John Maddock 25 Feb '02

25 Feb '02

>I have succesfully built the regex library >under msvc6sp5, using the vc6-sltport.mak file. > >But I notice that the compiler gives me warnings >relating to the microsoft stl include directories: > >example: vc98\include\iterator: blah blah blah Then you aren't compiling / linking to STLport >Should it not be linking to the stlport include files? Yes. Did you either * update your INCLUDE and LIB environment variables to point to STLport. or * invoke the makefile using something like: nmake CXXFLAGS="-Ic:\STLport-4.5.1\stlport" -fvc6-stlport.mak - John Maddock http://ourworld.compuserve.com/homepages/john_maddock/

2 1

Thread support?
by John Maddock 24 Feb '02

24 Feb '02

>If I'm using Boost in a single threaded app, do I need to define >BOOST_DISABLE_THREADS to avoid Boost using locks, etc. internally? You don't need to, but it may remove some redundent code, if your app is single threaded *and* links to a multithreaded runtime. - John Maddock http://ourworld.compuserve.com/homepages/john_maddock/

4 4

Problem linking with regex on Win32
by John Maddock 23 Feb '02

23 Feb '02

>Run-time Library: Multithreaded DLL/Debug Multithreaded DLL > >I've got a couple of problems trying to get my app to link against regex. > >I've tried linking to the debug and release versions of both the DLL and >non-DLL versions of the regex library and in each case I get errors about >unresolved external symbols for w32_regex_traits. > >w32_regex_traits.obj has been produced by Jam. > >In addition the static version winges about lots of locally defined symbols. > >I've specified BOOST_REGEX_NO_LIB as the generated filenames are not what >Jam produces. There could be a number of problems: Where the libs compiled with STLport (even a small error in the STLport include path could have messed this up)? The debug STLport libs are probably compiled by jam with __STL_DEBUG defined, your source will need to set this also. If you want to check your jam compiled libs, get a dump of the symbols they contain - if they're using the Dinkumware std lib then you'll see them referencing std::basic_string, release STLport will reference _STL::basic_string, and debug STLport will reference _STLD::basic_string. Failing that just create a static lib project in your IDE and add the regex sources to that with the build setting you want (this is probably the quickest solution IMO). Finally define BOOST_REGEX_STATIC_LINK to suppress the import/export warnings - John Maddock http://ourworld.compuserve.com/homepages/john_maddock/

1 0

Building regex with msvc6sp5 and stlport
by boxerab 22 Feb '02

22 Feb '02

Hello, I have succesfully built the regex library under msvc6sp5, using the vc6-sltport.mak file. But I notice that the compiler gives me warnings relating to the microsoft stl include directories: example: vc98\include\iterator: blah blah blah Should it not be linking to the stlport include files? I have added the stlport directory location into the mak file, and I have it added to the list of include directories via the compiler gui. Thanks. Aaron Boxer boxerab(a)NOSPAMyahoo.com

1 0

Iterators
by Colin Fox 21 Feb '02

21 Feb '02

This isn't a boost specific message per se, I guess, but I thought someone here may know the answer. I have a list<> of smart_ptrs. Some of the elements in the list are ready for processing under various circumstances. What I'd like would be a custom iterator that when I say "++i" it checks the element to see if it's ready, and if not, advance to the next, and so on until it finds a ready element. If it doesn't find one, then i == list.end(). This would simulate having a list that contained only ready elements, without having to have multiple lists. I have a number of books on C++, but I can't figure out from them how to create a custom iterator. Can anyone help? -- Colin Fox CF Consulting Inc. cfox(a)crystalcherry.com

2 1

[BGL] BGL Book Erratum
by Eric Eide 21 Feb '02

21 Feb '02

Page 12, Figure 1.2: the edge (a,d) should be black, and (b,d) should be gray. ...unless `breadth_first_search' is using the `delay_map' in some way that is not obvious to me. Eric. -- ------------------------------------------------------------------------------- Eric Eide <eeide(a)cs.utah.edu> . University of Utah School of Computing http://www.cs.utah.edu/~eeide/ . +1 (801) 585-5512 voice, +1 (801) 581-5843 FAX

2 1

const smart pointers
by nckgl 21 Feb '02

21 Feb '02

how do I define const smart pointer? for example for "int" type 1. scoped_ptr<const int> 2. const scoped_ptr<int> If the latter then it may be better to re-define get() as follows T* get(){ return px; } // never throws const T* get()const { return px; } // never throws Now scoped_ptr::get() is defined as follows T* get() const { return px; } // never throws The same apply to other accessors (operator-> and so on)

2 1

Problem linking with regex on Win32
by Dale Peakall 21 Feb '02

21 Feb '02

I'll try and add some content before sending a message this time ;) Platform: 2K Compiler: VC6 SP5 Library: stlport-4.0 Boost: 1.27.0 Build Tool for Boost: Jam Run-time Library: Multithreaded DLL/Debug Multithreaded DLL I've got a couple of problems trying to get my app to link against regex. I've tried linking to the debug and release versions of both the DLL and non-DLL versions of the regex library and in each case I get errors about unresolved external symbols for w32_regex_traits. w32_regex_traits.obj has been produced by Jam. In addition the static version winges about lots of locally defined symbols. I've specified BOOST_REGEX_NO_LIB as the generated filenames are not what Jam produces. Here's the full details: --------------------Configuration: request_line_test - Win32 Debug-------------------- Linking... http_request_line.obj : error LNK2001: unresolved external symbol "__declspec(dllimport) public: static void __cdecl boost::w32_regex_traits<char>::transform_primary(class _STL::basic_string<char,struct std::char_traits<char>,class _STL::allocator<c har> > &,class _STL::basic_string<char,struct std::char_traits<char>,class _STL::allocator<char> > const &)" (__imp_?transform_primary@?$w32_regex_traits@D@boost@@SAXAAV?$basic_string@D U?$char_traits@D@std@@V?$allocator@D@_STL@@@_STL@@ABV34@@Z) http_request_line.obj : error LNK2001: unresolved external symbol "__declspec(dllimport) public: static bool __cdecl boost::w32_regex_traits<char>::lookup_collatename(class _STL::basic_string<char,struct std::char_traits<char>,class _STL::allocator< char> > &,char const *,char const *)" (__imp_?lookup_collatename@?$w32_regex_traits@D@boost@@SA_NAAV?$basic_string @DU?$char_traits@D@std@@V?$allocator@D@_STL@@@_STL@@PBD1@Z) http_request_line.obj : error LNK2001: unresolved external symbol "__declspec(dllimport) public: __thiscall boost::bad_expression::bad_expression(class _STL::basic_string<char,struct std::char_traits<char>,class _STL::allocator<char> > const &)" (__ imp_??0bad_expression@boost@@QAE@ABV?$basic_string@DU?$char_traits@D@std@@V? $allocator@D@_STL@@@_STL@@@Z) http_request_line.obj : error LNK2001: unresolved external symbol "__declspec(dllimport) public: static class _STL::basic_string<char,struct std::char_traits<char>,class _STL::allocator<char> > __cdecl boost::re_detail::w32_traits_base::error_strin g(unsigned int)" (__imp_?error_string@w32_traits_base@re_detail@boost@@SA?AV?$basic_string@DU ?$char_traits@D@std@@V?$allocator@D@_STL@@@_STL@@I@Z) http_request_line.obj : error LNK2001: unresolved external symbol "__declspec(dllimport) public: static void __cdecl boost::w32_regex_traits<char>::transform(class _STL::basic_string<char,struct std::char_traits<char>,class _STL::allocator<char> > & ,class _STL::basic_string<char,struct std::char_traits<char>,class _STL::allocator<char> > const &)" (__imp_?transform@?$w32_regex_traits@D@boost@@SAXAAV?$basic_string@DU?$char_ traits@D@std@@V?$allocator@D@_STL@@@_STL@@ABV34@@Z) Debug/request_line_test.exe : fatal error LNK1120: 5 unresolved externals Error executing link.exe. request_line_test.exe - 6 error(s), 0 warning(s) Thanks, - Dale.

1 0

scoped_try_lock
by schalk_cronje＠nai.com 20 Feb '02

20 Feb '02

I was wondering about this line in boost::detail::thread::scoped_try_lock: if(m_locked) throw lock_error(); Since it is known that the lock attempt might fail and we do not want to block until the lock becomes available, is it not better to simply return false in the above case instead of throwing lock_error? ----------------------------------[ .signature ]--- Schalk W. Cronjé, Codernaut, Webshield Engineering, Network Associates. ++C or C++ ?

2 1

Permutation Iterator Adaptor Problem
by Jeff Flinn - wwnet 20 Feb '02

20 Feb '02

I'm trying to use the Permutation Iterator adaptor on MSV++ w/SP5 with boost_1_27_0. Below is a simplification of the example on the web site, which results in the compiler error found below function main: Any ideas? #include <list> #include <vector> #include <boost/permutation_iterator.hpp> int main(int argc, char* argv[]) { typedef std::vector < int > tElements; typedef tElements::iterator tEItr; typedef std::list < int > tIdxs; typedef tIdxs::iterator tIItr; typedef std::ostream_iterator< int > tOItr; tElements elements( 1, 1 ); tIdxs indices ( 1, 1 ); typedef boost::permutation_iterator_generator< tEItr, tIItr >::type tPItr; tPItr begin = boost::make_permutation_iterator( elements.begin(), indices.begin() ); int val = *begin; return 0; } error C2440: 'initializing' : cannot convert from 'struct boost::detail::iterator_traits_::undefined<void>' to 'int' Source or target has incomplete type

5 8

boost::regex compilation errors on RedHat 7.1/gcc 2.96
by John Maddock 19 Feb '02

19 Feb '02

>I'm new to boost and I'm primarily interested in the regex library but I get >some scary looking errors when trying to compile on RedHat. I imagine that >someone must have tried this already. >Thanks for any help you can offer. Unfortunately it's a known problem with gcc 2.96 (which was never officially released remember), gcc 2.95.x or gcc 3.x are both fine however. If anyone has a fix for redhat 2.96 gcc then I'd be happy to apply any patches - but it's not a gcc version I have access to. - John Maddock http://ourworld.compuserve.com/homepages/john_maddock/

1 0

boost.function as parameter of class template
by richielee616 19 Feb '02

19 Feb '02

I want to use boost.function object as a parameter of class template: template< function1<void,int> F > class foo { // ... }; but VC6 tells me "F : template parameter can never be initialized" why?

3 2

boost::regex compilation errors on RedHat 7.1/gcc 2.96
by Gerry Woods 18 Feb '02

18 Feb '02

Hi, I'm new to boost and I'm primarily interested in the regex library but I get some scary looking errors when trying to compile on RedHat. I imagine that someone must have tried this already. Thanks for any help you can offer. Gerry >uname -a Linux gloria.we.mediaone.net 2.4.2-2 #1 Sun Apr 8 20:41:30 EDT 2001 i686 unknown >gcc -v Reading specs from /usr/lib/gcc-lib/i386-redhat-linux/2.96/specs gcc version 2.96 20000731 (Red Hat Linux 7.1 2.96-81) >make -f gcc.mak g++ -o gcc/boost_regex/cregex.o -c -O2 -I../../../ ../src/cregex.cpp ../../../boost/regex.hpp: In function `iterator boost::re_detail::re_is_set_member (iterator, iterator, const boost::re_detail::re_set_long *, const boost::reg_expression<charT, traits_type, Allocator> &) [with iterator = boost::re_detail::mapfile_iterator, charT = char, traits_type = boost::regex_traits<char>, Allocator = allocator<char>]': ../../../boost/regex/detail/regex_match.hpp:600: instantiated from `boost::re_detail::query_match_aux (iterator, iterator, boost::match_results<iterator, Allocator> &, const boost::reg_expression<charT, traits, Allocator2> &, unsigned int, boost::re_detail::_priv_match_data<iterator, Allocator> &, iterator *) [with iterator = boost::re_detail::mapfile_iterator, Allocator = allocator<char>, charT = char, traits = boost::regex_traits<char>, Allocator2 = allocator<char>]' ../../../boost/regex/detail/regex_match.hpp:1177: instantiated from `boost::re_detail::reg_grep2 (Predicate, I, I, const boost::reg_expression<charT, traits, Allocator2> &, unsigned int, A2) [with Predicate = boost::re_detail::pred4, I = boost::re_detail::mapfile_iterator, charT = char, traits = boost::regex_traits<char>, A = allocator<char>, A2 = allocator<char>]' ../../../boost/regex/detail/regex_match.hpp:1836: instantiated from `boost::regex_grep (Predicate, iterator, iterator, const boost::reg_expression<charT, traits, Allocator2> &, unsigned int) [with Predicate = boost::re_detail::pred4, iterator = boost::re_detail::mapfile_iterator, charT = char, traits = boost::regex_traits<char>, Allocator = allocator<char>]' ../src/cregex.cpp:387: instantiated from here ../../../boost/regex.hpp:244: Internal compiler error in scan_region, at except.c:2809 Please submit a full bug report. See <URL:http://bugzilla.redhat.com/bugzilla/> for instructions. make: *** [gcc/boost_regex/cregex.o] Error 1

1 0

Threads and Smart Ptrs
by Colin Fox 16 Feb '02

16 Feb '02

Greetings, everyone. I'm currently having some trouble with a heavily multithreaded app which uses objects shared between threads via smart pointers. It's a multi-user application, where each user has a thread, and when one user sends a message to another (or broadcasts to all), a message object is created, and a smart pointer to that message is put into a queue for each thread. I'm using pthread_mutex for locking the queues for each thread. This program will sometimes work flawlessly for hours, and other times it will die within moments of starting. Pretty much every time it dies, it's because the message object has been freed while there are still smart pointers pointing to it. I know that the recent version of the smart pointer library was supposed to have added thread-safety to it, but I'm wondering if anyone else is having similar troubles. I'm using gcc 3.0.3 on Linux, and boost 1.27. I also discovered some things in the gcc documentation having to do with threads, (eg: when you compile the compiler, you have to tell it to build multi-threaded programs). And there are various threading flags that can be used during a compile, and I'm not sure which to use (or all of them?): -D_PTHREADS -D_REENTRANT -pthread : I'm using all those right now. Is that wrong? Any help would be greatly appreciated. It's driving me mad! :) Regards, Colin -- Colin Fox CF Consulting Inc. cfox(a)telus.net

3 8

Solaris CC version of Boost
by Kostas Kavoussanakis 15 Feb '02

15 Feb '02

Hello, I need to use boost with Solaris CC. Is this possible? Many thanks in advance, Kostas

4 3

Regex.hpp compile problem
by John Maddock 15 Feb '02

15 Feb '02

>I have some compile problems when I include regex.hpp from boost 1.27.0, >that seem to be internal to the interaction between my platform and >compiler. > >Are these known problems, and if so, what is the solution? > >ratts:~/cpp/classperf$ uname -a >Linux ratts 2.2.6 #46 Tue Apr 27 16:40:54 CDT 1999 i486 unknown >ratts:~/cpp/classperf$ gcc -v >Reading specs from /usr/lib/gcc-lib/i486-linux/2.7.2.3/specs >gcc version 2.7.2.3 Sorry, but I don't think that either boost or the regex lib has ever been testsed on a compiler that old (gcc 2.7?) You could try reading about boost's configuration options (libs/config/config.htm) and then running the configure script under libs/config. - John Maddock http://ourworld.compuserve.com/homepages/john_maddock/

1 0

The first question: How to build???
by olexander_shyrokov 15 Feb '02

15 Feb '02

Hello. Using: Windows 2000, MSVC 6, Stlport 4.5 I got a problem with building bost using jam. Actually what I need is regex, but I want to build all of them (for practice) :). I've downloaded jam, then I even built it from tools/build/jam_src, so it looks like I do have the correct version of the jam. So I'm making cd c:\src\boost then jam -sBOOST_ROOT=. -sTOOLS="msvc-stlport" And what I've got begins from: ./tools/build\boost-base.jam:1531: in subvariant-target *** argument error * rule dll-files ( module implib ? : sources * : target-type ? ) Can anyone help me with this? Thanks.

1 0

C++ socketstreams
by nils_ljunggren 14 Feb '02

14 Feb '02

This is not my favourite design but when using TCP/IP I belive this to be extra-ordinary: [lib.sockstream] The header <sockstream> defines four class templates and six types that associate stream buffers with sockets and assists reading and writing to and from sockets. In addittion <sockstream> defines three operators that extracts connection-oriented streams from connection-oriented server-streams. Header <sockstream> synopsis namespace sock { template <class charT, class traits= std::char_traits<charT> > class basic_socketbuf; typedef basic_socketbuf<char> socketbuf; typedef basic_socketbuf<wchar_t> wsocketbuf; template <class charT, class traits= std::char_traits<charT> > class basic_isocketstream; typedef basic_isocketstream<char> isocketstream; typedef basic_isocketstream<wchar_t> wisocketstream; template <class charT, class traits= std::char_traits<charT> > class basic_osocketstream; typedef basic_osocketstream<char> osocketstream typedef basic_osocketstream<wchar_t> wosocketstream; template <class charT, class traits= std::char_traits<charT> > class basic_socketstream; typedef basic_socketstream<char> socketstream; typedef basic_socketstream<wchar_t> wsocketstream; template <class charT, class traits> basic_isocketstream& operator >> (basic_isocketstream<charT, traits>& at, basic_isocketstream<charT, traits>& cs); template <class charT, class traits> basic_isocketstream& operator >> (basic_isocketstream<charT, traits>& at, basic_osocketstream<charT, traits>& cs); template <class charT, class traits> basic_isocketstream& operator >> (basic_isocketstream<charT, traits>& at, basic_socketstream<charT, traits>& cs); } Please reply to mailto:nlj@adr.dk [This is a Boost library proposal. - Mod]

1 0

Regex.hpp compile problem
by Dr. Ian McDonald 14 Feb '02

14 Feb '02

Hi, I have some compile problems when I include regex.hpp from boost 1.27.0, that seem to be internal to the interaction between my platform and compiler. Are these known problems, and if so, what is the solution? ratts:~/cpp/classperf$ uname -a Linux ratts 2.2.6 #46 Tue Apr 27 16:40:54 CDT 1999 i486 unknown ratts:~/cpp/classperf$ gcc -v Reading specs from /usr/lib/gcc-lib/i486-linux/2.7.2.3/specs gcc version 2.7.2.3 g++ performer.cpp In file included from /usr/local/include/boost/regex.hpp:44, from classperf.h:5, from performer.cpp:1: /usr/local/include/boost/regex/detail/regex_stack.hpp:47: parse error before `<' /usr/local/include/boost/regex/detail/regex_stack.hpp:52: `Allocator' was not declared in this scope /usr/local/include/boost/regex/detail/regex_stack.hpp:52: template argument 2 is invalid /usr/local/include/boost/regex/detail/regex_stack.hpp:52: `type' is not a class or namespace /usr/local/include/boost/regex/detail/regex_stack.hpp:52: warning: ANSI C++ forbids typedef which does not specify a type /usr/local/include/boost/regex/detail/regex_stack.hpp:52: confused by earlier errors, bailing out Thanks, Ian -- Dr. Ian McDonald Website Developer, No Fuss Websites.com T: +44 (0) 20 761 32110 F: +44 (0) 20 769 25461 -- Dr. Ian McDonald Website Developer, No Fuss Websites.com T: +44 (0) 20 761 32110 F: +44 (0) 20 769 25461

1 0

Distribution guidelines
by Edward Diener 12 Feb '02

12 Feb '02

I didn't see any guidelines for distributing the Boost header files in an implementation. Are there any ? As an example I may use only a small number of the header files for my distribution, so I assume I am not constrained to deliver all the header files nor am I constrained to deliver the full Boost distribution for any given version. While I can query the end-user during installation about having a specific version of Boost, and not install Boost files if the user does have a specific version, it does not seem as if I have to install the entire distribution, or even the entire set of header files if I am installing locally to my own directory structure. It would be nice if Boost actually had an install in its distribution because then , under Windows where I work, there would be a registry entry which I could read during the installation of any product which uses Boost. Has anyone ever suggested this, or is it seen as outside the boundaries of Boost ?

1 0

Regex questions
by Edward Diener 12 Feb '02

12 Feb '02

1) Support for Borland's C++ Builder 3 was dropped in moving the Regex++ implementation to Boost. Was this dropped because BCB3 can not support Boost, or Regex++, or was it just too much work to get it working with the Boost Regex++ version ? 2) Configuring Regex++ builds. Do I use user.hpp to configure the build, or is this used at the point of usage, or both ? If so, how do I know if BOOST_REGEX_NO_TEMPLATE_SWITCH_MERGE applies to a given compiler, and what does BOOST_REGEX_NO_W32 actually do. Finally what do the locale defines actually do ? Does defining the CPP or C locales constrain the Boost classes to use those locales or is it just setting a default locale which I can switch when instantiating the template classes ?

1 0

Poll results for Boost-Users
by Boost-Users＠yahoogroups.com 12 Feb '02

12 Feb '02

The following Boost-Users poll is now closed. Here are the final results: POLL QUESTION: Yahoo! groups can be configured so that only the moderators can view membership list, or so that membership lists can be viewed by anyone (email addresses are always munged for non-moderators; my email address would appear as something like jim.hyslop@.le...) Do you want the membership list to be freely available to be viewed by anyone, or do you want the membership list kept private so only the moderators can view the list? CHOICES AND RESULTS - I want only the moderators to be able to view the membership list, 0 votes, 0.00% - I want anyone to be able to view the membership list, 0 votes, 0.00% For more information about this group, please visit http://groups.yahoo.com/group/Boost-Users For help with Yahoo! Groups, please visit http://help.yahoo.com/help/us/groups/

2 2

Possible interest in select_by_predicate?
by Jonathan Brownell 11 Feb '02

11 Feb '02

I work in doing programming involving quite a bit of data analysis, and lately I've gotten sick and tired of doing routine searches on vectors and other linear containers to pull out maximum/minimum values. I ended up sitting down and writing a unary function object that retains a value based on any predicate. An example is worth a thousand words: int array[10] = { 5, 4, 6, 3, 9, 0, 7, 2, 8, 1 }; int maximum = std::for_each(&array[0], &array[10], select_by_predicate<int, std::greater>()); int minimum = std::for_each(&array[0], &array[10], select_by_predicate<int, std::less>()); assert(maximum == 9 && minimum == 0); Another example, using select_by_predicate independently: select_by_predicate<int, std::greater> max_error(0); for(loop through data samples) { double error; ... analyze data sample error ... max_error.compare(error); // same as max_error(error) } std::cout << "Maximum error: " << max_error; Is select_by_predicate something that boost users would be interested in? It's been helpful to me in all kinds of contexts. -Jonathan

3 4

Any use of a Singleton<> template
by sixfurdk 08 Feb '02

08 Feb '02

I currently working on a Singleton<> template, which currently has these features. 1) Supports the same interface/concepts as auto_ptr<> 2) One Line option to create a working singleton 3) Possible to use different Singletons of same type using names (simultaneously) 4) Possible to store different Singleton Objects under the same name (not simultaneously) 5) Possible to Release By Reference (Optional, Not Default) 6) Automatic Cleanup at program termination (Optional, Default) It can be used in the following manner: class SingletonObject { void someFunction(); ... }; Singleton<SingletonObject> singleton; singleton->someFunction(); Is there any interrest in such a class? Peter Sixhøj

2 2

tokenizer compilation problem with gcc 3.0.3 and stlport
by fintaeph 07 Feb '02

07 Feb '02

Hi all, I have been having trouble getting the tokenizer examples to compile using gcc 3.0.3 and stlport. I am using the example code from http://www.boost.org/libs/tokenizer/escaped_list_separator.htm, with the following compiler output: test.cpp: In instantiation of `::boost::::boost::iterator_ada ptor<::boost::detail::::boost::detail::token_iterator_base<co nst char *>,::boost::detail::::boost::detail::tokenizer_polic y<::_STL::::_STL::basic_string<char,::_STL::::_STL::char_trai ts<char>,::_STL::::_STL::allocator<char> >,::boost::::boost:: escaped_list_separator<char,::_STL::::_STL::char_traits<char> > >,::_STL::::_STL::basic_string<char,::_STL::::_STL::char_t raits<char>,::_STL::::_STL::allocator<char> >,const ::_STL::: :_STL::basic_string<char,::_STL::::_STL::char_traits<char>,:: _STL::::_STL::allocator<char> > &,const ::_STL::::_STL::basic _string<char,::_STL::::_STL::char_traits<char>,::_STL::::_STL ::allocator<char> > *,::_STL::forward_iterator_tag,int>': test.cpp:11: instantiated from here test.cpp:11: `sizeof' applied to incomplete type `::boost:::: boost::STATIC_ASSERTION_FAILURE<false>' If anyone has encountered and solved this problem before, I would greatly appreciate knowing what I'm doing wrong. Thanks, Chris. P.S. I get similar results with all the tokenizer examples.

3 3

modifed boost::stringtok
by hicks 06 Feb '02

06 Feb '02

Hello, I have created a modifed version of boost::stringtok() (the template function in boost\pending) with the aim of proving a more convient programmer interface. (It is called stringtok_2() below, but the interface is identical to stringtok()). The present version expects a container of objects which can be assigned a std::string. The modifed version is designed to accept a container of objects which can be converted to from std::string, at present "int" and "float" in addition to "std::string". E.g. char ac[] = "1 2 3 4 5"; std::vector<int> vi; boost::stringtok_2(vi,ac); std::vector<float> vf; boost::stringtok_2(vf,ac); std::vector<std::string> vs; boost::stringtok_2(vs,ac); As you can see in the cases for "int" and "float", the programmer can avoid having to create a vector of std::string and then convert them to int (or float) after calling stringtok. The implementation is achieved through template specialization. Behind the interface is an overloaded stringtok_2, template<typename Container, class Cvt> stringtok_2(Container l, Cvt cvt, const std::string s, const std::string ws) which takes a functor argument cvt which does the string to type conversion. The hithertoe used interface template<typename Container> stringtok_2(Container l, const std::string s, const std::string ws) calls the overloaded stringtok_2 with a converting functor string_cvt_ftr<Container::value_type>. string_cvt_ftr has a default declaration and two specializations, one for "int" and one for "float". template <class T> struct string_cvt_ftr { T operator()(const std::string& s) { return s; } }; template <> struct string_cvt_ftr<int> { int operator()(const std::string& s) { return std::atoi(s.c_str()); } }; template <> struct string_cvt_ftr<float> { float operator()(const std::string& s) { return std::atof(s.c_str()); } }; That is the partial specialization. Note that a vector of std::string can still be passed as the container argument. Since the interface semantics of are a superset of boost::stringtok(), I wonder if this could be substituted as a version-up, and use the same name. However, judging from the mail I see on this list, it is possible that some compilers might not handle it, so maybe that wouldn't be a good idea. I am sending this to boost-users since I do not currently recieve plain boost mail. I include the full code (including test code) below. Craig Hicks Engineer, KGK Tokyo //////////////////////////////////////////////////////////////////// // stringtok_2.h //--------------------------------------------------------------------------- #ifndef stringtok_2H #define stringtok_2H //--------------------------------------------------------------------------- #include <string> #include <cstring> // for strchr /***************************************************************** // modified with partial template specialization for int, float containers 2002.2.6 // Craig Hicks /***************************************************************** * This is the only part of the implementation that I don't like. * It can probably be improved upon by the reader... */ namespace stringtok_2_ns { inline bool isws (char c, char const * const wstr) { using namespace std; return (strchr(wstr,c) != NULL); } } namespace boost { /***************************************************************** * Simplistic and quite Standard, but a bit slow. This should be * templatized on basic_string instead, or on a more generic StringT * that just happens to support ::size_type, .substr(), and so on. * I had hoped that "whitespace" would be a trait, but it isn't, so * the user must supply it. Enh, this lets them break up strings on * different things easier than traits would anyhow. */ template <typename Container, typename Cvt> void stringtok_2 ( Container &l, Cvt cvt, std::string const &s, char const * const ws = " \t\n" ) { using namespace stringtok_2_ns; typedef std::string::size_type size_type; const size_type S = s.size(); size_type i = 0; while (i < S) { // eat leading whitespace while ((i < S) && (isws(s[i],ws))) ++i; if (i == S) return; // nothing left but WS // find end of word size_type j = i+1; while ((j < S) && (!isws(s[j],ws))) ++j; // add word l.push_back(cvt(s.substr(i,j-i))); // set up for next loop i = j+1; } } template <class T> struct string_cvt_ftr { T operator()(const std::string& s) { return s; } }; template <> struct string_cvt_ftr<int> { int operator()(const std::string& s) { return std::atoi(s.c_str()); } }; template <> struct string_cvt_ftr<float> { float operator()(const std::string& s) { return std::atof(s.c_str()); } }; template <typename Container> void stringtok_2 ( Container &l, std::string const &s, char const * const ws = " \t\n" ) { string_cvt_ftr<Container::value_type> cvt; stringtok_2(l, cvt, s, ws); } } // namespace boost #endif /////////////////////////////////////////////////////////////////// // test code void test_stringtok_2(std::ostream& os) /* Expected output:: int 1, 2, 3, 4, 5, float 1, 2, 3, 4, 5, string 1, 2, 3, 4, 5, */ { char ac[] = "1 2 3 4 5"; os << "int" << std::endl; std::vector<int> vi; boost::stringtok_2(vi,ac); std::copy(vi.begin(), vi.end(), std::ostream_iterator<int,char>(os,", ")); os << std::endl; os << "float" << std::endl; std::vector<float> vf; boost::stringtok_2(vf,ac); std::copy(vf.begin(), vf.end(), std::ostream_iterator<float,char>(os,", ")); os << std::endl; os << "string" << std::endl; std::vector<std::string> vs; boost::stringtok_2(vs,ac); std::copy(vs.begin(), vs.end(), std::ostream_iterator<std::string,char>(os,", ")); os << std::endl; }

2 2

Tokenizer question
by Edward Diener 06 Feb '02

06 Feb '02

Two tokenizer questions 1) I do not understand the constructor parameters to the char_delimits_separator class which is the default TokenizerFunction model. I assume the constructor would enable one to specify the delimiters for each token. I assume that the "returnable" parameter is a string literal of delimiters which are also returned as tokens and that "nonreturnable" is a string literal of delimiters which are not returned as tokens. I assume that the intersection of these string literals consists of all the delimiters. Given these assumptions, what is the purpose of the bool "return_delims" first parameter ? If "returnable" specifies a non-empty string literal, then why shouldn't these be the delimiters returned as tokens irregardless of the setting of "return_delims". If "returnable" specifies an empty string literal, then no delimiters will be returned as tokens once again irregardless of the setting of "return_delims". Would someone please explain why "return_delims" exists as a parameter in conjunction with the meaning of the "returnable" parameter ? It seems utterly redundant and unnecessary. 2) How does one create one own's TokenizerFunction to be plugged into the tokenizer class template as the first template type ? The documentation on TokenizerFunction concept leaves me utterly confused on a practical level. I assume I am creating a template class here despite the name which suggests it is a function, but the documentation never explains what it is. Maybe someone from Boost or John Bandela should consider updating it.

2 2

Another Tokenizer question
by s1imshady86 06 Feb '02

06 Feb '02

How do you specify that a white space is a returnable delimiter? The obvious, char_delimiters_separator<char> func (true, " "); Doesnt work. I know it's rather newbish question, but please help. A little more documentaion on token_iterator and TokenizerFunction concept (and perhaps the three specialized ones) would help greatly! Thanks, Ray

1 0

[Fwd: Re: [Boost-Users] Four Questions on boost::shared_ptr]
by hicks 05 Feb '02

05 Feb '02

-------- Original Message -------- Subject: Re: [Boost-Users] Four Questions on boost::shared_ptr Date: Tue, 05 Feb 2002 10:08:25 +0900 From: hicks <hicks(a)kgk.co.jp> To: Boost-Users(a)yahoogroups.com, Duane Murphy <duanemurphy(a)mac.com> References: <B8838630.133F2%darin(a)bentspoon.com> <20020204170343.12718(a)mail.murphyslogic.com> Hi >>You should normally use std::vector unless you have some special reason to >>use boost:: scoped_array and boost::shared_array. Those classes are provided >>both for completeness, and because occasionally there are such special >>reasons. But not often. > >I consider user vector<> often. However there is a cost. For a fixed size >allocation of a buffer there is only the data allocated. If you use a >vector<> the vector also includes (for most implementations) the current >capacity, the current size, and the allocator. There is another sometimes very big overhead incurred by std::vector, and not incurred by by new T[]/ delete[]. Most implementions of std::vector will enter a loop and call a destructor on each element of the array, even if there is no machine code associated with that destructor. At least Borlands implemention of delete[] automatically detects this condition and does not insert a loop to call the destructors. This could be avoided if std::vector used a traits type to determine whether to enter a loop calling destructors. Craig Hicks KGK Tokyo Duane Murphy wrote: >--- At Mon, 4 Feb 2002 00:28:32 -0800, Darin Adler wrote: > >>On 2/3/02 11:54 PM, "Jon Wang" <webmaster(a)boost.100ok.com> <mailto:webmaster@boost.100ok.com> wrote: >> >>>1. Mr Stroustrup said that there wasn't a need for auto_array, for "a >>> >better > >>>solution is to use a vector". So, should we use vector or >>>scoped_array/shared_array? >>> >>You should normally use std::vector unless you have some special reason to >>use boost:: scoped_array and boost::shared_array. Those classes are provided >>both for completeness, and because occasionally there are such special >>reasons. But not often. >> > >I consider user vector<> often. However there is a cost. For a fixed size >allocation of a buffer there is only the data allocated. If you use a >vector<> the vector also includes (for most implementations) the current >capacity, the current size, and the allocator. > >I would be interested in finding a class that is somewhere between >allocating my own buffers and vector<>. Low overhead for simple >allocations; no resizing or growing. Even in this case, in order to >support iterator semantics the size is going to be needed. > >Sigh. > >I suppose a case like this might be when scoped_array would be used? > > ...Duane > > > > >Info: <http://www.boost.org> >Wiki: <http://www.crystalclearsoftware.com/cgi-bin/boost_wiki/wiki.pl> >Unsubscribe: <mailto:boost-users-unsubscribe@yahoogroups.com> > > >Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/ > > > > >

1 0

Re: [Boost-Users] Four Questions on boost::shared_ptr
by Darin Adler 05 Feb '02

05 Feb '02

On 2/3/02 11:54 PM, "Jon Wang" <webmaster(a)boost.100ok.com> wrote: > 1. Mr Stroustrup said that there wasn't a need for auto_array, for "a better > solution is to use a vector". So, should we use vector or > scoped_array/shared_array? You should normally use std::vector unless you have some special reason to use boost:: scoped_array and boost::shared_array. Those classes are provided both for completeness, and because occasionally there are such special reasons. But not often. > 2. In the document, four implementations are said to have been discussed: > Direct detached, Indirect detached, Embedded detached and Placement detached. > I've tried to describle them (Are I right? See the attached file), but I don't > understand the Placement detached. Could someone please tell me what it's > like? The concept here is that the object is allocated in a special way, which require use of placement, so the count is in a header before the object. This is a form of the "embedded attached" scheme that does not require changes to the original object's class, but it does require a special form of new, so you couldn't just call the normal "new" and then give the object to such a smart pointer. [Note: There was no attached file.] > 3. In the file smart_ptr.hpp, we can see the private function > shared_ptr::share. > > I'm sorry that I don't understand that reason why ++*rpn should be done before > dispose(). Would someone please give me an example? Or is it like this? This function is gone from the latest implementation of shared_ptr slated for the next boost release, so it's probably not worthwhile to discuss this particular aspect of the old implementation in detail. The code you enclosed looks something like the kind of code that caused trouble -- the key is that deleting the old object pointed to can end up deleting the new shared pointer in some cases, and this must not happen before incrementing the reference count. The new implementation avoids this issue by using the well-known "copy and swap" idiom for implementing assignment, and is easier to understand. > 4. Why not use policies? I'm afraid that the word "parameterization will > discourage users" might not be always true, for we can use default parameters. We'll probably be using policies in future version, if we can work out all the issues. Andrei Alexandrescu is considering submitting his smart pointer class template from his Loki library to Boost for formal review, which is the most likely candidate for a Boost policy-based smart pointer. If it turns out well enough, it may replace all the existing smart pointer class templates. -- Darin

3 3

Re: [Boost-Users] Four Questions on boost::shared_ptr
by Jon Wang 04 Feb '02

04 Feb '02

>[Note: There was no attached file.] Oh, sorry! Here is the attached code. Am I right? Thanks very much. But still I haven't understand placement attached:-) #ifndef COUNTED_PTR_HPP #define COUNTED_PTR_HPP #include <cstring> #include <boost/config.hpp> // counted_ptr --------------------------------------------------------------// template <typename T> class RefLinking { protected: RefLinking(T* p) { init(p); } ~RefLinking() { dispose(); } template<typename Y> RefLinking(const RefLinking<Y>& r) { insert(&r); } // never throws RefLinking(const RefLinking& r) { insert(&r); } // never throws public: template<typename Y> void operator=(const RefLinking<Y>& r) { share(&r); } void operator=(const RefLinking& r) { share(&r); } void reset(T* p=0) { if ( px == p ) return; // fix: self-assignment safe dispose(); init(p); } // reset T* get() const { return px; } // never throws long use_count() const { long i = 0; const RefLinking* p = prev; while(p){ p = p->prev; ++i; } p = this; while(p){ p = p->next; ++i; } return i; } // never throws #if ( defined(BOOST_NO_MEMBER_TEMPLATES) && !defined(BOOST_MSVC6_MEMBER_TEMPLATES) ) || !defined( BOOST_NO_MEMBER_TEMPLATE_FRIENDS ) private: #endif T* px; RefLinking *prev, *next; // Don't split this line into two; that causes problems for some GCC 2.95.2 builds #if !defined( BOOST_NO_MEMBER_TEMPLATES ) && !defined( BOOST_NO_MEMBER_TEMPLATE_FRIENDS ) template<typename Y> friend class RefLinking; #endif void init(T* p) { px = p; prev = 0; next = 0; } void dispose() { if(prev) prev->next = next; else if(next) next->prev = prev; else delete px; } template <class Y> void insert(Y* rr) { RefLinking* r = (RefLinking*)rr; px = r->px; prev = (r); next = r->next; r->next = this; if(next) next->prev = this; } template <class Y> void share(Y* r) { if ((void*)this != (void*)r) { dispose(); insert(r); } } // share }; //*/ template <typename T> class EmbeddedAttached { protected: EmbeddedAttached(T* p) { init(p); } ~EmbeddedAttached() { dispose(); } template<typename Y> EmbeddedAttached(const EmbeddedAttached<Y>& r) : ptr(r.ptr) { // never throws if(ptr) ++(ptr->pn); } EmbeddedAttached(const EmbeddedAttached& r) : ptr(r.ptr) { if(ptr) ++(ptr->pn); } // never throws public: template<typename Y> void operator=(const EmbeddedAttached<Y>& r) { share(r.ptr); } void operator=(const EmbeddedAttached& r) { share(r.ptr); } void reset(T* p=0) { if ( ptr == p ) return; // fix: self-assignment safe dispose(); init(p); } // reset T* get() const { return ptr; } // never throws long use_count() const { return (ptr)? ptr->pn: 0; } // never throws #if ( defined(BOOST_NO_MEMBER_TEMPLATES) && !defined(BOOST_MSVC6_MEMBER_TEMPLATES) ) || !defined( BOOST_NO_MEMBER_TEMPLATE_FRIENDS ) private: #endif T* ptr; // Don't split this line into two; that causes problems for some GCC 2.95.2 builds #if !defined( BOOST_NO_MEMBER_TEMPLATES ) && !defined( BOOST_NO_MEMBER_TEMPLATE_FRIENDS ) template<typename Y> friend class EmbeddedAttached; #endif void init(T* p) { ptr = p; if(ptr) ++(ptr->pn); } void dispose() { if(ptr&&--(ptr->pn)== 0) delete ptr; } void share(T* r) { if (ptr != r && r) { // Q: why not px != rpx? A: fails when both == 0 ++(r->pn); // done before dispose() in case rpn transitively // dependent on *this (bug reported by Ken Johnson) dispose(); ptr = r; } } // share }; template <typename T> class IndirectDetached { protected: IndirectDetached(T* p) { init(p); } ~IndirectDetached() { dispose(); } template<typename Y> IndirectDetached(const IndirectDetached<Y>& r) : ptr(r.ptr) { // never throws ++(ptr->pn); } IndirectDetached(const IndirectDetached& r) : ptr(r.ptr) { ++(ptr->pn); } // never throws public: template<typename Y> void operator=(const IndirectDetached<Y>& r) { share(r.ptr); } void operator=(const IndirectDetached& r) { share(r.ptr); } void reset(T* p=0) { if ( ptr->px == p ) return; // fix: self-assignment safe dispose(); init(p); } // reset T* get() const { return ptr->px; } // never throws long use_count() const { return ptr->pn; } // never throws #if ( defined(BOOST_NO_MEMBER_TEMPLATES) && !defined(BOOST_MSVC6_MEMBER_TEMPLATES) ) || !defined( BOOST_NO_MEMBER_TEMPLATE_FRIENDS ) private: #endif struct IDHelper{ T* px; long pn; IDHelper(T* p): px(p), pn(1) {} ~IDHelper() { delete px; } }; IDHelper* ptr; // Don't split this line into two; that causes problems for some GCC 2.95.2 builds #if !defined( BOOST_NO_MEMBER_TEMPLATES ) && !defined( BOOST_NO_MEMBER_TEMPLATE_FRIENDS ) template<typename Y> friend class IndirectDetached; #endif void init(T* p) { try { ptr = new IDHelper(p); } catch (...) { delete p; throw; } } void dispose() { if(--(ptr->pn) == 0) delete ptr; } template <class Y> void share(IDHelper* r) { if ((void*)ptr != (void*)r) { // Q: why not px != rpx? A: fails when both == 0 ++(r->pn); // done before dispose() in case rpn transitively // dependent on *this (bug reported by Ken Johnson) dispose(); ptr = r; } } // share }; //*/ template <typename T> class DirectDetached { protected: DirectDetached(T* p) : px(p) { try { pn = new long(1); } catch (...) { delete p; throw; } } ~DirectDetached() { dispose(); } template<typename Y> DirectDetached(const DirectDetached<Y>& r) : px(r.px) { // never throws ++*(pn = r.pn); } DirectDetached(const DirectDetached& r) : px(r.px) { ++*(pn = r.pn); } // never throws public: template<typename Y> void operator=(const DirectDetached<Y>& r) { share(r.px, r.pn); } void operator=(const DirectDetached& r) { share(r.px, r.pn); } void reset(T* p=0) { if ( px == p ) return; // fix: self-assignment safe if (--*pn == 0) { delete px; } else { // allocate new reference counter try { pn = new long; } // fix: prevent leak if new throws catch (...) { ++*pn; // undo effect of --*pn above to meet effects guarantee delete p; throw; } // catch } // allocate new reference counter *pn = 1; px = p; } // reset T* get() const { return px; } // never throws long use_count() const { return *pn; } // never throws // Tasteless as this may seem, making all members public allows member templates // to work in the absence of member template friends. (Matthew Langston) // Don't split this line into two; that causes problems for some GCC 2.95.2 builds #if ( defined(BOOST_NO_MEMBER_TEMPLATES) && !defined(BOOST_MSVC6_MEMBER_TEMPLATES) ) || !defined( BOOST_NO_MEMBER_TEMPLATE_FRIENDS ) private: #endif T* px; // contained pointer long* pn; // ptr to reference counter // Don't split this line into two; that causes problems for some GCC 2.95.2 builds #if !defined( BOOST_NO_MEMBER_TEMPLATES ) && !defined( BOOST_NO_MEMBER_TEMPLATE_FRIENDS ) template<typename Y> friend class DirectDetached; #endif void dispose() { if (--*pn == 0) { delete px; delete pn; } } void share(T* rpx, long* rpn) { if (pn != rpn) { // Q: why not px != rpx? A: fails when both == 0 ++*rpn; // done before dispose() in case rpn transitively // dependent on *this (bug reported by Ken Johnson) dispose(); px = rpx; pn = rpn; } } // share }; template<typename T, class Storage = DirectDetached<T> > class counted_ptr: public Storage { public: typedef T element_type; explicit counted_ptr(T* p = 0) : Storage(p) {} template<typename Y, typename S> counted_ptr(const counted_ptr<Y, S>& r) : Storage(r) {} // never throws template<typename Y, typename S> counted_ptr& operator=(const counted_ptr<Y, S>& r) { *static_cast<Storage*>(this) = static_cast<const S&>(r); return *this; } counted_ptr(const counted_ptr& r) : Storage(r) {} // never throws counted_ptr& operator=(const counted_ptr& r) { *static_cast<Storage*>(this) = static_cast<const Storage&>(r); return *this; } T& operator*() const { return *get(); } // never throws T* operator->() const { return get(); } // never throws bool unique() const { return use_count() == 1; } // never throws void swap(counted_ptr& other) // never throws { using std::memcpy; const int size = sizeof(counted_ptr); char temp[size]; memcpy(temp, &other, size); memcpy(&other, this, size); memcpy(this, temp, size); } }; // counted_ptr #endif // COUNTED_PTR_HPP Jon Wang 2002-02-04

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Re: [Boost-Users] Four Questions on boost::shared_ptr
by Darin Adler 04 Feb '02

04 Feb '02

On 2/4/02 12:51 AM, "Jon Wang" <webmaster(a)boost.100ok.com> wrote: > [Non-text portions of this message have been removed] I should have been more clear. This list doesn't allow attached files. -- Darin

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Re: [Boost-Users] Four Questions on boost::shared_ptr
by Jon Wang 04 Feb '02

04 Feb '02

>[Note: There was no attached file.] Oh, sorry! Here is the attached file. Am I right? Jon Wang 2002-02-04 [Non-text portions of this message have been removed]

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Unable to compile thread example on the document.
by 御風只配做笨木頭 04 Feb '02

04 Feb '02

Hi, I cannot compile the thread example listed on the document: http://www.boost.org/libs/thread/doc/thread.html#Example I'm using g++ 2.95.3 on a FreeBSD 4.x box. Here are the exact environment and compile error messages: % uname -a FreeBSD XXX.foo.bar 4.5-PRERELEASE FreeBSD 4.5-PRERELEASE #0: Tue Jan 8 03:14:40 CST 2002 root@XXX.foo.bar:/usr/src/sys/compile/kernel.XXX i386 % g++ -v Using builtin specs. gcc version 2.95.3 20010315 (release) [FreeBSD] % cat test_thread0.cpp #include <boost/thread/xtime.hpp> #include <boost/thread/thread.hpp> #include <iostream> struct thread_alarm { thread_alarm(int secs) : m_secs(secs) { } void operator()() { boost::xtime xt; boost::xtime_get(&xt, ::boost::TIME_UTC); xt.sec += m_secs; boost::thread::sleep(xt); std::cout << "alarm sounded..." << std::endl; } int m_secs; }; void run() { int secs = 5; std::cout << "setting alarm for 5 seconds..." << std::endl; boost::thread thrd(thread_alarm(secs)); std::cout << "main()" << std::endl; thrd.join(); } int main() { run(); } % g++ -I/usr/local/include test_thread0.cpp test_thread0.cpp: In function `void run()': test_thread0.cpp:28: request for member `join' in `thrd', which is of non-aggregate type `boost::thread ()(thread_alarm)' The boost library is installed through FreeBSD's ports collection which the boost version is 1.26.0. I've tried to figure out where the problem is and failed to find the definition of class thread. Do I miss something? Or, is it just a freebsd porting problem? ps. The example seems lack of a xtime inclution. So I add the #include at the first line: #include <boost/thread/xtime.hpp> -- Chien-Chou Hung / Jeff Hung / 洪健洲 (Big5) National Chiao Tung University Institute of Information Management 交通大學資訊管理所碩士生 http://www.jeffhung.idv.tw/ mailto:jeffhung.iim90g@nctu.edu.tw

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Four Questions on boost::shared_ptr
by Jon Wang 04 Feb '02

04 Feb '02

Hi, I've got several questions about the former version of boost::shared_ptr. Would someone please help me? 1. Mr Stroustrup said that there wasn't a need for auto_array, for "a better solution is to use a vector". So, should we use vector or scoped_array/shared_array? 2. In the document, four implementations are said to have been discussed: Direct detached, Indirect detached, Embedded detached and Placement detached. I've tried to describle them (Are I right? See the attached file), but I don't understand the Placement detached. Could someone please tell me what it's like? 3. In the file smart_ptr.hpp, we can see the private function shared_ptr::share. void share(T* rpx, long* rpn) { if (pn != rpn) { ++*rpn; // done before dispose() in case rpn transitively // dependent on *this (bug reported by Ken Johnson) dispose(); px = rpx; pn = rpn; } } // share I'm sorry that I don't understand that reason why ++*rpn should be done before dispose(). Would someone please give me an example? Or is it like this? #include <boost/smart_ptr.hpp> struct A { boost::shared_ptr<A> v; }; int main() { A* pa = new A; boost::shared_ptr<A> ptr(pa); ptr = pa->v; } 4. Why not use policies? I'm afraid that the word "parameterization will discourage users" might not be always true, for we can use default parameters. Jon Wang 2002-01-31

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Fw: Warning to all list owners and moderators
by Ihsan Ali Al Darhi 04 Feb '02

04 Feb '02

I don't know if this is true, but I received it on another group.... > > > > > > I don't know how valid this is but those of you > who belong to yahoo groups > might > want to pass it along to your list owners. > > > > I just got this from another group owner. I have > > heard of this happening, > > > and in one case banned a guy that made a similar > > attempt with one of my > > > groups. > > > Someone has been joining communities with the > nickname YAHOO COMMUNITY > MONITOR, and then posting the following: Yahoo > Community Monitor says: > Yahoo Group Managers have been receiving a few > complaints about your > group.I am required to join your site and monitor > it for about one month.I > will not do anything to damage or ruin your site,I > am only required to > monitor it.The only thing required of you is to > accept my application and > make me a Manager of your group for the time I am > there. If you cannot > meet > these requirements,Yahoo will have to shut your > group down. > DO NOT!! make this person a manager! SHE/HE is a fake, and has been deleting groups once made a manager. BAN the member immediately. Please let other groups know about this problem. I just wanted to let ya'll know. Wouldn't want anything to happen to your groups. Mohammed

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Re: [Boost-Users] Suggestion -- Boost Building
by John Maddock 02 Feb '02

02 Feb '02

>> I used to be able to build this, but since the boost.build stuff came along, > I've been completely unable to build anything at all. The documentation is > worse than useless because it's so self-contradictory.... Don't forget that the regex makefiles are still there if you want them, there is nothing that says that you have to use Jam if you don't want to... - John Maddock http://ourworld.compuserve.com/homepages/john_maddock/

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boost python and smart pointers
by Martin Strubel 01 Feb '02

01 Feb '02

Hello, I've lately experimented with Boost.Python and found it pretty useful. Though I've run into one thing which I couldn't figure out by the documentation, I hope someone can give me a hint there: I have a function returning a pointer to an 'owned' structure, i.e. its container takes care of creation and deletion. In Python, I want to wrap this pointer into a direct reference to the struct, i.e. no copying. To guard the access and make sure the object can't be accessed after the deletion, I want to wrap the smart pointer AS a python object. for example, a C++ function returning an 'owned' face from a mesh: FaceSmartPtr Mesh::addFace() { .. } should be wrapped for access in Python like: f = mesh.addFace() with subsequent calls for face manipulation like: f.addVertex((0.0, 0.0, 0.0)) where this should again call something like if (f_sptr.isValid()) f_sptr->addVertex(...); else throw_pyException_ptrInvalid(); Does Boost support this automatically ? Or do I have to wrap all these functions myself ? Greetings, - Strubi -- Martin Strubel, Software Hooligan strubi(a)blender.nl www.blender.nl Not a Number - 3D Enabling Technology tel. +31 40 2501231 Eindhoven, The Netherlands

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RE: [Boost-Users] Suggestion -- Boost Building
by Wismar, John 01 Feb '02

01 Feb '02

In my case (the most recent how-can-I-build-this question) I'm trying (unsuccessfully) to use the regex library, which requires compiling.... I used to be able to build this, but since the boost.build stuff came along, I've been completely unable to build anything at all. The documentation is worse than useless because it's so self-contradictory.... -------------------------- John Wismar mailto:jwismar@alldata.com > -----Original Message----- > From: Duane Murphy [mailto:duanemurphy@mac.com] > Sent: Saturday, January 26, 2002 12:15 AM > To: Boost Users > Subject: [Boost-Users] Suggestion -- Boost Building > > > It seems a lot of questions come up on the list about > "building" the boost libraries. > > I wonder how many of these people realize that most of the > functionality of the Boost "libraries" is completely > encapsulated in the header files? There are significant > portions like regex and the graph library (?) that do require > compiling, but much of it does not. > > Is there anything that can be done to make it more clear that > compiling is often not necessary? > > I'm just trying to relieve some stress from people who may > very well not require compiling. And I have compassion for > those that do and are having trouble. > > I'm not sure exactly what can be done, but it might be worth > some thought. > > ...Duane > > > > ------------------------ Yahoo! Groups Sponsor > ---------------------~--> Sponsored by VeriSign - The Value > of Trust Pinpoint the right security solution for your > company - FREE Guide from industry leader VeriSign gives you > all the facts. > http://us.click.yahoo.com/lWSNbC/WdiDAA/yigFAA> /EbFolB/TM > > > -------------------------------------------------------------- > -------~-> > > Info: <http://www.boost.org> > Wiki: <http://www.crystalclearsoftware.com/cgi-bin/boost_wiki/wiki.pl> > Unsubscribe: <mailto:boost-users-unsubscribe@yahoogroups.com> > > > Your use of Yahoo! Groups is subject to > http://docs.yahoo.com/info/terms/ > >

2 1

Cannot find regular expression symbols in Solaris debug
by phlasnicek 31 Jan '02

31 Jan '02

Hi, I am using Solaris Workshop 5.0 and I am using boost libraries for regular expressions. Everything builds fine and runs ok except when I try to attach to the process and run the debugger. I get the following error: warning: cannot demangle '__1c9uX__unnamed_6ofsRKVdR8zYNQre_get_error_str6FI_pkc_' Anyone have any suggestions, I would appreciate it very much. Thanks Paul

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RE: [Boost-Users] Digest Number 81
by Anthony Kolarik 31 Jan '02

31 Jan '02

> Date: Tue, 29 Jan 2002 20:22:32 -0500 (EST) > From: Jeremy Siek <jsiek(a)cs.indiana.edu> > Subject: RE: RE: Dependencies for tokenizer? > > On Tue, 29 Jan 2002, Jeff Garland wrote: > jeff> > jeff> I'm sure there is. It is a matter of getting the "25 lines of > jeff> actual code" (my guess) in those 47 headers that tokenizer > jeff> really needs into a small header. I'm sure with a small > jeff> effort you could do it. Perhaps you could even find a way to > jeff> improve the overall design in the process. > > Well, it could get a little messy. The iterator adaptors use > some stuff > from the type_traits headers, which have lots of workarounds > for different > compilers, etc., etc. > > For a super simple C++ stringtok see the header > > boost/pending/stringtok.hpp > > It's not an official boost library, but you might find it fits > your needs. > > Cheers, > Jeremy Thank you for pointing out the pitfalls of reworking tokenizer and for pointing out boost/pending/stringtok.hpp, it serves fine for my purposes. -- Tony K.

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1_26_0: regex/thread on W32 build via jam?
by John Maddock 31 Jan '02

31 Jan '02

>that's what I'm doing now. >I just want to fully understand the new jam way of building/using boost, >and eg to see what is neccessary to use the 'new way'. >Will the 'old way' be deprecated someday? Probably not any time soon. >Does/will the new way support static libs? It does for regex, can't comment on anything else though. - John Maddock http://ourworld.compuserve.com/homepages/john_maddock/

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RE: [Boost-Users] Re: boost::pool + shared memory
by Tom Matelich 30 Jan '02

30 Jan '02

I've been using the ACE_Malloc framework from ACE (http://cs.wustl.edu/~schmidt/ACE.html) to solve a similar problem (sharing statics between DLL's). It takes a little while to figure out because the documentation is a little slim, but once you do it pays off pretty quickly. Doxygen documentation for ACE_Malloc is at: http://doc.ece.uci.edu/Doxygen/Current/html/ace/classACE__Malloc__T.html and the shared_mem memory pool is at: http://doc.ece.uci.edu/Doxygen/Current/html/ace/classACE__Shared__Memory__Po ol.html I ended up not having to write an STL allocator using ACE_Malloc, but I don't think it would be too difficult. If you get it right, a lot of ACE users would be your friend :) Tom Matelich > -----Original Message----- > From: xpav_2000 [mailto:alex@pavloff.net] > Sent: Tuesday, January 29, 2002 6:01 PM > To: Boost-Users(a)yahoogroups.com > Subject: [Boost-Users] Re: boost::pool + shared memory > > > --- In Boost-Users@y..., Tom Matelich <tmatelich@z...> wrote: > > Looks like pool may not be what I need, darn. I like > > to weasel as many boost classes into my project as possible. > > I've got a similar question -- I've got a whole pile of strings that > I want to share between processes, and I was thinking a reference- > counted string implementation with the actual data in shared memory > would be a good way to do that. > > Do you think a memory pool placed in shared memory, with the string > class modified to allocate/deallocate there would work? > > > > ------------------------ Yahoo! Groups Sponsor > ---------------------~--> > Tiny Wireless Camera under $80! > Order Now! FREE VCR Commander! > Click Here - Only 1 Day Left! > http://us.click.yahoo.com/nuyOHD/7.PDAA/yigFAA/EbFolB/TM > -------------------------------------------------------------- > -------~-> > > Info: <http://www.boost.org> > Wiki: <http://www.crystalclearsoftware.com/cgi-bin/boost_wiki/wiki.pl> > Unsubscribe: <mailto:boost-users-unsubscribe@yahoogroups.com> > > > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/

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1_26_0: regex/thread on W32 build via jam?
by Bruno.Voigt＠ic3s.de 30 Jan '02

30 Jan '02

> Date: Tue, 29 Jan 2002 07:55:46 -0500 > From: John Maddock <john_maddock(a)compuserve.com> > Subject: 1_26_0: regex/thread on W32 build via jam? > > >But how do I have to change my project settings for a static executable? > >I just changed the the lib search path to this new monster path and it > >does not work > >The linker is missing the vc7-re300dm.lib then. > > why not carry on using the libs you built from the makefiles? Hi John, that's what I'm doing now. I just want to fully understand the new jam way of building/using boost, and eg to see what is neccessary to use the 'new way'. Will the 'old way' be deprecated someday? Does/will the new way support static libs? > >And how to link the boost thread stuff? > >Is it supported for statically linked apps at all? > Build threadmon.cpp into a dll, and the rest of the source into a static > lib with the options you want. Okay, thanks, I will try this combination. bye, Bruno

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RE: [Boost-Users] boost::pool + shared memory
by Tom Matelich 30 Jan '02

30 Jan '02

Looks like pool may not be what I need, darn. I like to weasel as many boost classes into my project as possible. > -----Original Message----- > From: Tom Matelich [mailto:tmatelich@zetec.com] > Sent: Monday, January 07, 2002 2:49 PM > To: 'boost-users(a)yahoogroups.com' > Cc: 'shammah(a)voyager.net' > Subject: [Boost-Users] boost::pool + shared memory > > > I need to build a system for having miscellaneous objects in > a shared memory > segment. Essentially, we need a few inter-process singletons. These > classes have STL containers, so I was looking at using > pool_allocator and > writing a UserAllocator to use ACE_Mem_Map ( > http://doc.ece.uci.edu/Doxygen/Current/html/ace/classACE__Mem_ > _Map.html#_det > ails ) or something. I just wanted to see if anyone had done anything > resembling this and could give me any pointers or tips. > > Thanks, > > Tom Matelich > > PS Why can't I see who is a member of this group? I wanted > to check to see > if Steve Cleary was a member. Sorry if you are Steve. > > ------------------------ Yahoo! Groups Sponsor > ---------------------~--> > Tiny Wireless Camera under $80! > Order Now! FREE VCR Commander! > Click Here - Only 1 Day Left! > http://us.click.yahoo.com/WoOlbB/7.PDAA/ySSFAA/EbFolB/TM > -------------------------------------------------------------- > -------~-> > > Info: <http://www.boost.org> > Wiki: <http://www.crystalclearsoftware.com/cgi-bin/boost_wiki/wiki.pl> > Unsubscribe: <mailto:boost-users-unsubscribe@yahoogroups.com> > > > Your use of Yahoo! Groups is subject to > http://docs.yahoo.com/info/terms/ > >

2 1

RE: Dependencies for tokenizer?
by Anthony Kolarik 30 Jan '02

30 Jan '02

> > > Any ideas about how to get this functionality w/o all the headers? Thanks, > > > -- Tony K. > > > In order to use the tokenizer classes I end up requiring 47 files, which > > What's wrong with 47 files? How much longer does it take to compile? It actually does slow things down noticeably, since it's a small project. > He might be sub setting boost and only wants to include the needed files. Exactly. I have 47 more files checked into source control that everybody else has to download (and have the tool check every time they refresh) so that I can parse a command line. I suppose I could check in the whole boost library, (~2000 files in the download I got,) but I'd rather just take what I need for now. > Anyway, this was brought up during the review, but at the time only 20 files > were needed (the very first tokenizer only need 2 boost headers). It was the > switch to iterator_adaptors that caused the include explosion at the time... Evidently reviewers thought 20 was reasonable, and I assume that some major problems are solved by the 47 headers that weren't by 20. I just wondered if there was a lighter weight way in boost to do my little tokenizing task. Is there? -- Tony K.

4 3

1_26_0: regex/thread on W32 build via jam?
by John Maddock 29 Jan '02

29 Jan '02

>But how do I have to change my project settings for a static executable? >I just changed the the lib search path to this new monster path and it >does not work >The linker is missing the vc7-re300dm.lib then. why not carry on using the libs you built from the makefiles? >And how to link the boost thread stuff? >Is it supported for statically linked apps at all? Build threadmon.cpp into a dll, and the rest of the source into a static lib with the options you want. - John Maddock http://ourworld.compuserve.com/homepages/john_maddock/

1 0

object_pool, O(N) destroy?
by kevin_godden＠agilent.com 29 Jan '02

29 Jan '02

Hi, I am considering using boost::object_pool for fast allocation and deallocation of likkle container/token objects. I need to make this as fast as possible, to this end I wonder why object_pool seems to use boost::pool::ordered_free() (O(N)) rather than the faster free() (O(1))? There must be a reason, but I can't seem to find it in the Lib's documentation. I would be interested in hearing if peoples experiences/comments on using object_pool. Thanks for reading! Kevin\

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RE: [Boost-Users] RE: object_pool, O(N) destroy?
by kevin_godden＠agilent.com 29 Jan '02

29 Jan '02

I agree, it does sound like a job for a Policy whatsit. If I get a chance I could try a few things and see if anything works out and let you know. Although, if time constraints work out the way I think they will, I might have to stick with a cut&paste solution! Kevin\ -----Original Message----- From: scleary(a)jerviswebb.com [mailto:scleary@jerviswebb.com] Sent: Tuesday, January 29, 2002 5:13 AM To: Boost-Users(a)yahoogroups.com Cc: shammah(a)voyager.net Subject: [Boost-Users] RE: object_pool, O(N) destroy? > -----Original Message----- > From: hicks [mailto:hicks@kgk.co.jp] > > It sounds like a case where a type trait, identifying the need for the > pool to responsible for deletion, > would be appropriate. Then objects which did not need to be destroyed > (e.g. ptrs, "plain" structs) > could be handled by optimized code. But that's more work than cut and > paste. Actually, the difference is in how the pool is used, not on the type of object being allocated. So it sounds more like a case for a policy-based design. Too bad, I just don't have time to do that right now... :( -Steve Info: <http://www.boost.org> Wiki: <http://www.crystalclearsoftware.com/cgi-bin/boost_wiki/wiki.pl> Unsubscribe: <mailto:boost-users-unsubscribe@yahoogroups.com> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/

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RE: object_pool, O(N) destroy?
by scleary＠jerviswebb.com 29 Jan '02

29 Jan '02

> -----Original Message----- > From: hicks [mailto:hicks@kgk.co.jp] > > It sounds like a case where a type trait, identifying the need for the > pool to responsible for deletion, > would be appropriate. Then objects which did not need to be destroyed > (e.g. ptrs, "plain" structs) > could be handled by optimized code. But that's more work than cut and > paste. Actually, the difference is in how the pool is used, not on the type of object being allocated. So it sounds more like a case for a policy-based design. Too bad, I just don't have time to do that right now... :( -Steve

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Dependencies for tokenizer?
by Anthony Kolarik 29 Jan '02

29 Jan '02

In order to use the tokenizer classes I end up requiring 47 files, which seems a little steep for my purposes. All I really need is to tokenize strings based on a couple of single char delimiters. Kind of a C++ step above strtok() was what I had in mind. Any ideas about how to get this functionality w/o all the headers? Thanks, -- Tony K.

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RE: [Boost-Users] object_pool, O(N) destroy?
by kevin_godden＠agilent.com 29 Jan '02

29 Jan '02

Thanks for the Info Steve, In this case, I am less interested in the pool's destructor as I _should_ have a 1 to 1 on malloc()ing and destroying the individual objects (if all goes well...). The pool will only be destroyed once during the lifetime of the application so I could probably suffer a O(N^2) pool destructor. I will try what you recommend in your postscript. Thanks again.. Kevin\ -----Original Message----- From: scleary(a)jerviswebb.com [mailto:scleary@jerviswebb.com] Sent: Monday, January 28, 2002 2:10 PM To: Boost-Users(a)yahoogroups.com Cc: shammah(a)voyager.net Subject: RE: [Boost-Users] object_pool, O(N) destroy? > From: kevin_godden(a)agilent.com [mailto:kevin_godden@agilent.com] > > I am considering using boost::object_pool for fast allocation and > deallocation of likkle container/token objects. I need to make this as fast > as possible, to this end I wonder why object_pool seems to use > boost::pool::ordered_free() (O(N)) rather than the faster > free() (O(1))? > > There must be a reason, but I can't seem to find it in the Lib's > documentation. The object_pool keeps its free list ordered because of the requirements of its destructor. Its destructor steps through the free list, calling the destructor for any objects that weren't freed. The current algorithm is O(N) because the free list is ordered; if it wasn't ordered, it would be O(N^2). I'll document this in the code. -Steve P.S. An object_pool without the destructor behaviour may be what you want. Boost.Pool doesn't provide one, but you could just cut & paste the object_pool, remove the destructor, and change ordered_malloc/ordered_free to the regular malloc/free (you also won't need nextof). Just note that if you ever construct something from that pool and don't destruct it, you enter the fun realm of undefined behaviour... :) Info: <http://www.boost.org> Wiki: <http://www.crystalclearsoftware.com/cgi-bin/boost_wiki/wiki.pl> Unsubscribe: <mailto:boost-users-unsubscribe@yahoogroups.com> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/

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1_26_0: regex/thread on W32 build via jam?
by Bruno.Voigt＠ic3s.de 28 Jan '02

28 Jan '02

Hi! For my statically linked application (w32/sol8/linux) I was up to now using only the boost regex library. I build the regex lib the oldstyle way going to the build path and calling nmake -f vc7.mak, etc. In the project settings I included the regex/build/vc7 path as an additional lib search path. The buld step works as expected this way. boost::thread does provide only the newstyle jam build way. So I downloaded the boost::winbuild stuff and tried to build the whole boost via jam -sBOOST_ROOT=. -sTOOLS=msvc. It shows some errors for some pytho stuff but builds the regex and thread lib part. So I get for example a path boost_1_26_0\libs\regex\build\bin\libboost_regex.lib\msvc\release\runtime-link-dynamic with a libboost_regex.lib But how do I have to change my project settings for a static executable? I just changed the the lib search path to this new monster path and it does not work The linker is missing the vc7-re300dm.lib then. And how to link the boost thread stuff? Is it supported for statically linked apps at all? Any suggestions on how to make use of the jam build stuff in the right way ae really appreciated. TIA, Bruno PS: will there be a working suncc-tools.jam file in the next release? -- Bruno.Voigt(a)ic3s.de # IC3S AG # Tel. +49.4106.655.105 # Fax. +49.4106.655.55 http://www.ic3s.de # Mobile +49.700.686.00.686 [Non-text portions of this message have been removed]

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RE: [Boost-Users] object_pool, O(N) destroy?
by scleary＠jerviswebb.com 28 Jan '02

28 Jan '02

> From: kevin_godden(a)agilent.com [mailto:kevin_godden@agilent.com] > > I am considering using boost::object_pool for fast allocation and > deallocation of likkle container/token objects. I need to make this as fast > as possible, to this end I wonder why object_pool seems to use > boost::pool::ordered_free() (O(N)) rather than the faster > free() (O(1))? > > There must be a reason, but I can't seem to find it in the Lib's > documentation. The object_pool keeps its free list ordered because of the requirements of its destructor. Its destructor steps through the free list, calling the destructor for any objects that weren't freed. The current algorithm is O(N) because the free list is ordered; if it wasn't ordered, it would be O(N^2). I'll document this in the code. -Steve P.S. An object_pool without the destructor behaviour may be what you want. Boost.Pool doesn't provide one, but you could just cut & paste the object_pool, remove the destructor, and change ordered_malloc/ordered_free to the regular malloc/free (you also won't need nextof). Just note that if you ever construct something from that pool and don't destruct it, you enter the fun realm of undefined behaviour... :)

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MacCVS Pro hints
by voidampersand 27 Jan '02

27 Jan '02

I'm trying to get with the program here, so I just got the boost sources from CVS, using MacCVS Pro. The main thing that tripped me up was the instructions on the SourceForge page have command lines that are word wrapped. Anyway, here are some MacCVS session settings that work for me: Remote Host Information Server Hostname: cvs.boost.sourceforge.net CVS Root: /cvsroot/boost CVS User Name: anonymous CVS Password: [+] Save Password Also, in "File Translation and Encoding" you will want to add these mappings before you check out: .hpp TEXT CWIE .cxx TEXT CWIE .jam TEXT CWIE .pdf TEXT CARO MacCVS Pro is available at <http://sourceforge.net/projects/maccvspro/>. Regards, Tom

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Re: [Boost-Users] memcmp, strlen, strcmp not found in string.h?
by Steven Woolgar 27 Jan '02

27 Jan '02

> My question: Why aren't they in STLPort's string.h? > Is it a voluntary omission, and if so, why? > Should I talk to the guys who created Boost instead? > Should I be asking this on the developer's mailing list?? =) If I am not mistaken, the standard C functions would be in the the standard C include files, not the C++ files. So: strlen would be in <cstring> the string class would be in <string> Note that the new include style does not have the .h at the end. HTH Woolie

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Suggestion -- Boost Building
by Duane Murphy 26 Jan '02

26 Jan '02

It seems a lot of questions come up on the list about "building" the boost libraries. I wonder how many of these people realize that most of the functionality of the Boost "libraries" is completely encapsulated in the header files? There are significant portions like regex and the graph library (?) that do require compiling, but much of it does not. Is there anything that can be done to make it more clear that compiling is often not necessary? I'm just trying to relieve some stress from people who may very well not require compiling. And I have compassion for those that do and are having trouble. I'm not sure exactly what can be done, but it might be worth some thought. ...Duane

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Compiling with VC7
by Wismar, John 25 Jan '02

25 Jan '02

I wonder if someone can help me get up and running with Boost using VC7. I've tried to follow the Boost Build documentation, and am running into problems. A description of different things I've tried is below. Thanks in advance for any help anyone can provide! So far I've downloaded the Windows version of Boost.Build, and have run boost-build.exe (I couldn't tell if it did anything.) I added the boost-build directory to my PATH by hand, along with the VC7/bin directory. I also remember some discussion about how jam couldn't handle VC's default install dir (which is, for the purposes of this discussion, where mine is) because it has spaces in it, so I've used SUBST to define Z: as my VS.NET path. When I run jam from the boost_1_26_0 dir, using: jam -sBOOST_ROOT=. -sTOOLS="msvc" I get errors that look like: msvc-C++-action libs\regex\build\bin\libboost_regex.lib\msvc\debug\runtime-link- dynamic\c_regex_traits.obj c_regex_traits.cpp c1xx : fatal error C1108: unable to find DLL: 'mspdb70.dll' Z:\vc7\bin\cl /Zm400 -nologo -GX -c -I"libs\regex\build" -Fo"libs\reg ex\build\bin\libboost_regex.lib\MSVC\debug\c_regex_traits.obj" -Tp"libs\regex\b uild\../src\c_regex_traits.cpp" ...failed msvc-C++-action libs\regex\build\bin\libboost_regex.lib\MSVC\debug\c_regex_traits.obj ... msvc-C++-action libs\regex\build\bin\libboost_regex.lib\MSVC\debug\c_regex_traits_common.obj c_regex_traits_common.cpp c1xx : fatal error C1108: unable to find DLL: 'mspdb70.dll' So I added VC7's common7/IDE/ directory to my path, because that's where mspdb70.dll lives, but it didn't resolve the issue. Delving deeper into the docs, I found the suggestion that I do: set TOOLS=msvc jam instead of what the top level docs say, but then I get a message that I didn't set the toolset, and I should use: set VISUALC=<path> set JAM_TOOLSET=VISUALC jam When I do that, I get: Compiler is Microsoft Visual C++ warning: unknown rule project-root warning: unknown rule subinclude warning: unknown rule subinclude warning: unknown rule subinclude warning: unknown rule subinclude ...found 7 targets... Etc. -------------------------- John Wismar mailto:jwismar@alldata.com

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mem_fn and references?
by Duane Murphy 25 Jan '02

25 Jan '02

I am trying to make a member function call to all objects returned by an iterator. mem_fn is giving me an error when trying to call get_pointer() for a reference object. There is no overload for get_pointer of a reference object. Is there some reason or should I be doing this differently. The long description is that I am iterating over a container of objects. I would like to make a member function call on each of these objects. Then I get an error that there is no matching function for get_pointer( obj ). I have solved this by providing my own get_pointer() overload specifically for obj to prevent any bad things from happening until I can found out what the real problem is. Here is some pseudo code to get things in the right orientation. class obj { public: void method(); }; class obj_iterator { public: obj& iterator::operator*() const { return obj_; } }; class obj_container { public: obj_iterator begin(); obj_iterator end(); } { ... obj_container c; foreach( c.begin(), c.end(), mem_fn( method ) ); } Thanks, ...Duane

3 5

Solaris/sparcWorks 5.0
by sebmarc 24 Jan '02

24 Jan '02

Does anybody know how to compile boost with Solaris 7 and sparcWorks 5.0. Looking at http://www.boost.org/tools/build/index.html, there is no place for this compiler. Any help appreciated. Thanks, Seb.

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RE: [Boost-Users] Subject: Poll results for Boost-Users
by Tom Matelich 24 Jan '02

24 Jan '02

I asked the original question that sparked this, and its because (at the root) I want to know whether feature requests need to be mirrored on the main boost list. So if I can be sure that the author of the library is at least listening to my boost-users message, I don't have to CC him/her or spam both lists. That is why I wanted access to the members, and as a support mechanism, why I thought it was important for boost-users. I realize membership != reading the messages, so perhaps my point is moot. > -----Original Message----- > From: Jim.Hyslop [mailto:jim.hyslop@leitch.com] > Sent: Wednesday, January 23, 2002 7:20 AM > To: 'Boost-Users(a)yahoogroups.com' > Subject: RE: [Boost-Users] Subject: Poll results for Boost-Users > > > Chris Little [SMTP:clittle@renlearn.ca] wrote: > > When the question first came up of allowing members to view > the membership > > list, one of the moderators started a poll (around the beginning of > > January). > That'd be me. > > > Unfortunately polling in this group is limited to moderators. > > The moderators then decided to discuss the issue amongst > themselves and > they > > haven't reported back. > > Hoo, boy, I seem to have dropped the ball on several counts here. > > First, my apologies for not cancelling the poll after > discovering polling > was limited to moderators. > > Second, my apologies for not reporting back to the group on > the results of > our discussion (I'm taking responsibility for this, since I'm > the one who > opened the can of worms in the first place). > > We identified a potential problem with spam email harvesting. > Granted, in > the public pages emails are hidden, so that only the first > letter of the > domain appears (my address, for example, would appear as > "jim.hyslop@l..." > One of the moderators pointed out: > > > About half of the email addresses on > > the first page start with either an a, h, or y. > > ... the problem is that when harvesting email addresses you > > don't need 100% accuracy. Just assume that a's are aol, all b's are > > bigfoot, all e's are earthlink, all h's are hotmail.com, > and all y's > > are yahoo.com. These letters are going to be [greater than] > half the list > and you > > will be correct [greater than] half the time. > > We could not come up with any compelling arguments in favour > of opening the > list. I believe the best summary was: > > > I'm not sure what the benefits of public membership would be. > > Arguments such as "I need to know if X is a member of > > the group" seem empty - this is a *mailing list* after all. > > To access individuals, you should get hold of them in > > other ways. If they are active members of the list, you'll > > still know they're members. > > No moderators actually spoke out in favour of opening the > list up, so the > status quo remains. > > We moderators are, of course, open to suggestions, and if a reasonably > strong argument comes up, then we will re-examine the issue. > If anyone feels > strongly about it, you can either post your rationale here or > email the > moderators at boost-users-owner(a)yahoogroups.com (the > 'boost-users-owner' > name is a bit misleading - email goes to all moderators, not > just to the > owner). > > Similarly, on the topic of polls themselves, the general > consensus was that > if or when we identify a good reason to run a poll, then we > will open up the > feature. Until then, there's no reason to change the status quo. > > -- > Jim > > > ------------------------ Yahoo! Groups Sponsor > ---------------------~--> > Tiny Wireless Camera under $80! > Order Now! FREE VCR Commander! > Click Here - Only 1 Day Left! > http://us.click.yahoo.com/nuyOHD/7.PDAA/yigFAA/EbFolB/TM > -------------------------------------------------------------- > -------~-> > > Info: <http://www.boost.org> > Wiki: <http://www.crystalclearsoftware.com/cgi-bin/boost_wiki/wiki.pl> > Unsubscribe: <mailto:boost-users-unsubscribe@yahoogroups.com> > > > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/

3 2

Re: [BGL] BFS and copy problem (was Re: [boost] Compilation)
by Jeremy Siek 24 Jan '02

24 Jan '02

Again, Luca, we can't help you unless you post the code (the complete C++ file). I can't just guess what is going wrong. You're probably forgetting to do something, and there's no way I can tell what that is based on what you've written below. On Thu, 24 Jan 2002, lucatoldo wrote: luca.t> I think there is something I do not know, rather important, about the luca.t> process of adding edges to the graph object. Infact, even in the luca.t> simple example/bfs.cpp if I swap the start with the ends, I get luca.t> different results. Namely: luca.t> luca.t> If I change the code from this luca.t> luca.t> boost::add_edge(0,2,G); luca.t> boost::add_edge(1,1,G); luca.t> boost::add_edge(3,1,G); luca.t> ... luca.t> boost::add_edge(4,1,G); luca.t> luca.t> to luca.t> luca.t> boost::add_edge(2,0,G); luca.t> boost::add_edge(1,1,G); luca.t> boost::add_edge(1,3,G); luca.t> ... luca.t> boost::add_edge(1,4,G); luca.t> luca.t> then I get luca.t> luca.t> the graph OK but the distances and the parent vectors are screwed: luca.t> luca.t> I get luca.t> luca.t> distances: 0 2 2 2 1 luca.t> instead of luca.t> distances: 0 2 1 2 2 luca.t> luca.t> and luca.t> luca.t> parent[0] = 0 luca.t> parent[1] = 4 luca.t> parent[2] = 4 luca.t> parent[3] = 4 luca.t> parent[4] = 0 luca.t> luca.t> instead of luca.t> luca.t> parent[0] = 0 luca.t> parent[1] = 2 luca.t> parent[2] = 0 luca.t> parent[3] = 2 luca.t> parent[4] = 2 luca.t> luca.t> I feel I am missing some basic knowledge on how to appropriately use luca.t> this powerful and amazingly fast system. I would love to learn the luca.t> missing bit. luca.t> luca.t> Looking forward your advice and sorry again for the dumminess of this luca.t> question. luca.t> luca.t> luca.t> Info: http://www.boost.org Send unsubscribe requests to: <mailto:boost-unsubscribe@yahoogroups.com> luca.t> luca.t> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/ luca.t> luca.t> ---------------------------------------------------------------------- Jeremy Siek http://php.indiana.edu/~jsiek/ Ph.D. Student, Indiana Univ. B'ton email: jsiek(a)osl.iu.edu C++ Booster (http://www.boost.org) office phone: (812) 855-3608 ----------------------------------------------------------------------

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RE: [Boost-Users] Subject: Poll results for Boost-Users
by Jim.Hyslop 24 Jan '02

24 Jan '02

Tom Matelich [SMTP:tmatelich@zetec.com] wrote: > I asked the original question that sparked this, and its because (at the > root) I want to know whether feature requests need to be mirrored on the > main boost list. So if I can be sure that the author of the library is at > least listening to my boost-users message, I don't have to CC him/her or > spam both lists. The moderators have agreed that one of our duties will be to ensure appropriate cross-pollination of messages. In other words, if a discussion here in Boost-Users raises an issue that is appropriate to the main Boost list (such as a feature request or a bug report), we will ensure it gets forwarded to that forum. Similarly, if someone posts a message to Boost that is more appropriate to this list, we will encourage the original poster to switch to this forum. -- Jim

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Adding edges to a graph. Problems.
by lucatoldo 24 Jan '02

24 Jan '02

I think there is something I do not know, rather important, about the process of adding edges to the graph object. Infact, even in the simple libs/graph/example/bfs.cpp if I swap the start with the ends, I get different results. Namely: If I change the code from this boost::add_edge(0,2,G); boost::add_edge(1,1,G); boost::add_edge(3,1,G); ... boost::add_edge(4,1,G); to boost::add_edge(2,0,G); boost::add_edge(1,1,G); boost::add_edge(1,3,G); ... boost::add_edge(1,4,G); then I get the graph OK but the distances and the parent vectors are screwed: I get distances: 0 2 2 2 1 instead of distances: 0 2 1 2 2 and parent[0] = 0 parent[1] = 4 parent[2] = 4 parent[3] = 4 parent[4] = 0 instead of parent[0] = 0 parent[1] = 2 parent[2] = 0 parent[3] = 2 parent[4] = 2 I feel I am missing some basic knowledge on how to appropriately use this powerful and amazingly fast system. I would love to learn the missing bit. Looking forward your advice and sorry again for the dumminess of this question.

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A tip from the Dr.
by jackthompson99 23 Jan '02

23 Jan '02

Hey guys, I sent an e-mail to Dr. Stroustrup a couple nights ago, and he replied, "Have a look at boost.org. They exist specifically to provide better libraries in the context of the C++ standard library and to act as a test bed for new library ideas". So, here I am. I've installed and built my boost libraries, and I'm trying to figure out how to dig in. Anyway, here's what I was telling the Dr. I've been using C for about a decade, and C++ for about 7 yrs. I'm a huge fan of your invention, and I honestly feel like your name should eventually be as well known as Tesla and Edison. And the Standard Template Library is an incredibly well engineered system. I have a way to use it that is generic enough that it may be a candidate to be another standard. I know that's a lot to say. I'd like to explain it briefly, but first I should explain why I find it useful. Since I started working with assembler, I've always felt like the language I was using was missing something. I've used an assortment of languages, and it seems like they are all missing the same thing. The main part isn't really missing from C++, it's just not commonly understood. The concept of virtual construction is the core of the issue. Now I know that this problem is solved, but it really could stand for just one more thing to wrap it up into something usable for any ordinary C++ developer. Using a virtual constructor by way of a template, a developer can easily create any kind of object based on any type of identifier, but what good is that when the developer has exhausted all of his efforts on just building a simple system to dynamically create objects. The developer needs a way to organize these objects, without building another data warehouse. And I have never heard of a complicated database that shouldn't be fully hierarchical. So, the system should be one hundred percent re-entrant. Well, I have such a beast. I'm not done with it yet. I'm just now finishing up a project for Textron, where some of this concept was cultivated into my skill set. I am having a rough time explaining the system to my boss, and I'm in a real bind, but that's another story. The main thing that I've learned from this job is that the world needs to come together on one simple international standard for dealing with data and persistent C++ objects. I've used my ClassFactory / DataStore system as a foundation for another library that I call the WinFactory. This system simply uses the ClassFactory / DataStore as a database manager. The objects held in the database are simply graphical user interface components. This worked out really well, `till by boss took it apart. But I have a version of it that I'm re-writing at home that is much better. The database can be held either in a simple text format, resembling hypertext, or a binary file. The system relies heavily on the memory manager, so fast memory allocation is required. I have also populated an MFC user interface with data held in these objects. The system seems to be able to flex with just about anything, and I feel like it could at least contribute to discussions about new standards that are based on your standards. By the way, I need to find a team that I can work with who has good work ethics and integrity. Suggestions would be much appreciated. ..... So, I've looked at the library list in Boost, and haven't recognized anything like what I've built. I would love to explain this system. But, again, this one belongs to Textron, and all of the documentation too. I need to find some time to build this system for Boost.org. The main concept behind the system is a warehouse environment. The warehouse hase isles of goods. Each isle is any length, and each isle contains exactly one type of product. And every product contains a single pointer which is initally NULL. This makes it so that when you pull the product off the shelf and open it, you will see whatever the product is ( characters, integers, strings, etc. ), and you will find one more thing. It's called the nest. Now, until you try to use the nest, it's empty (NULL). But when you need it, it is created. What is this nest you ask? It's another warehouse. Just like the one that it is contained within. So, the entier concept is one hundred percent re-entrant. This makes it easy to build hierarchical infrastructures. The objects can be virtually any C++ thing. They persist with the greatest of ease to simple IO objects. User interfaces are easy to build with this system. Content editors view it as a script. C++ programmers view the script as C++ objects. Again, I need to finish re-writing the system, and I need to document it. But I feel like it is a candidate to become another Boost library. What do you think?????

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RE: [Boost-Users] Subject: Poll results for Boost-Users
by Jim.Hyslop 23 Jan '02

23 Jan '02

Chris Little [SMTP:clittle@renlearn.ca] wrote: > When the question first came up of allowing members to view the membership > list, one of the moderators started a poll (around the beginning of > January). That'd be me. > Unfortunately polling in this group is limited to moderators. > The moderators then decided to discuss the issue amongst themselves and they > haven't reported back. Hoo, boy, I seem to have dropped the ball on several counts here. First, my apologies for not cancelling the poll after discovering polling was limited to moderators. Second, my apologies for not reporting back to the group on the results of our discussion (I'm taking responsibility for this, since I'm the one who opened the can of worms in the first place). We identified a potential problem with spam email harvesting. Granted, in the public pages emails are hidden, so that only the first letter of the domain appears (my address, for example, would appear as "jim.hyslop@l..." One of the moderators pointed out: > About half of the email addresses on > the first page start with either an a, h, or y. > ... the problem is that when harvesting email addresses you > don't need 100% accuracy. Just assume that a's are aol, all b's are > bigfoot, all e's are earthlink, all h's are hotmail.com, and all y's > are yahoo.com. These letters are going to be [greater than] half the list and you > will be correct [greater than] half the time. We could not come up with any compelling arguments in favour of opening the list. I believe the best summary was: > I'm not sure what the benefits of public membership would be. > Arguments such as "I need to know if X is a member of > the group" seem empty - this is a *mailing list* after all. > To access individuals, you should get hold of them in > other ways. If they are active members of the list, you'll > still know they're members. No moderators actually spoke out in favour of opening the list up, so the status quo remains. We moderators are, of course, open to suggestions, and if a reasonably strong argument comes up, then we will re-examine the issue. If anyone feels strongly about it, you can either post your rationale here or email the moderators at boost-users-owner(a)yahoogroups.com (the 'boost-users-owner' name is a bit misleading - email goes to all moderators, not just to the owner). Similarly, on the topic of polls themselves, the general consensus was that if or when we identify a good reason to run a poll, then we will open up the feature. Until then, there's no reason to change the status quo. -- Jim

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RE: [Boost-Users] Subject: Poll results for Boost-Users
by Chris Little 23 Jan '02

23 Jan '02

When the question first came up of allowing members to view the membership list, one of the moderators started a poll (around the beginning of January). Unfortunately polling in this group is limited to moderators. The moderators then decided to discuss the issue amongst themselves and they haven't reported back. Chris > -----Original Message----- > From: James Curran/MVP [mailto:jamescurran@mvps.org] > Sent: Wednesday, January 23, 2002 8:29 AM > To: Boost-Users(a)yahoogroups.com > Subject: RE: [Boost-Users] Subject: Poll results for Boost-Users > > > How long was that poll open for? > > Truth, > James Curran > > > -----Original Message----- > From: Boost-Users(a)yahoogroups.com > [mailto:Boost-Users@yahoogroups.com] > Subject: Poll results > for Boost-Users > > > The following Boost-Users poll is now closed. Here are the > final results: > > > CHOICES AND RESULTS > - I want only the moderators to be able to view the > membership list, 0 votes, 0.00% > - I want anyone to be able to view the membership list, 0 > votes, 0.00% > [Non-text portions of this message have been removed]

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RE: [Boost-Users] Subject: Poll results for Boost-Users
by James Curran/MVP 23 Jan '02

23 Jan '02

How long was that poll open for? Truth, James Curran -----Original Message----- From: Boost-Users(a)yahoogroups.com [mailto:Boost-Users@yahoogroups.com] Subject: Poll results for Boost-Users The following Boost-Users poll is now closed. Here are the final results: CHOICES AND RESULTS - I want only the moderators to be able to view the membership list, 0 votes, 0.00% - I want anyone to be able to view the membership list, 0 votes, 0.00%

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Ann: Forward lookahead asserts now supported by regex lib
by John Maddock 23 Jan '02

23 Jan '02

The regex lib, now has experimental support for perl style forward lookahead assertions, using the syntax extensions: (?=exp) positive zero width forward assertion on exp. (?!exp) negative zero width forward assertion on exp. I'm currently looking for anyone willing to test these, and for real world test cases to add to the regression tests, before documenting the extensions and making them "official". Many thanks. - John Maddock http://ourworld.compuserve.com/homepages/john_maddock/

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error with thread.hpp
by thrashmodule 19 Jan '02

19 Jan '02

I got this message: c:\boost_1_26_0\boost\thread\thread.hpp(17) : fatal error C1189: #error : Thread support is unavailable! I use VC++ on Win98 so now what??????????

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Class destructor invocation - possible by hand?
by Jonathan Brownell 19 Jan '02

19 Jan '02

I have a question for all you C++ gurus. I'm writing a class that I would like to use the following technique in, and I'm not sure if it's portable or even legal, although VC++6 and VC++.NET, which I'm compiling in, work beautifully with it. Consider the following class, a very simplified example that I wrote to demonstrate: class House { public: explicit House(const int rooms) : m_rooms(rooms) { } ~House() { } private: const int m_rooms; }; Pretty straightforward. I'd like m_rooms to remain const to protect it from accidental modification by member functions, since it will *never* be changed during operation. Now, the first problem that arises is that this is illegal: House housingComplex[100]; Because, obviously, the constructor requires that the number of rooms be passed to it. (Yes, we could create it as an array of House pointers and create them dynamically, but in my case that will require inconveniences by everybody using my class.) So, we make it a default parameter and add an assignment operator: class House { public: explicit House(const int rooms = -1) : m_rooms(rooms) { } ~House() { } House& operator =(const House& source); private: const int m_rooms; }; When rooms == -1, the House is considered to be uninitialized. Now, we can do the following: House housingComplex[100]; housingComplex[0] = House(5); housingComplex[1] = House(4); (etc) The question is, how to implement the assignment operator? This is my method: House& House::operator =(const House& source) { assert(m_rooms == -1); this->~House(); new(this) House(source); return *this; } Yikes! I know this looks weird. First, assert verifies in debug mode that the object is in its uninitialized state. Then, the destructor is called manually to destruct the class and its contents. (In the actual class I'm working on, there are numerous member variables that must be appropriately destructed, and all of them are - I've checked.) Simply calling ~House(); will not compile, because the compiler assumes I'm trying to use the ~ operator illegally, so I have to call it through the 'this' pointer. Then, the placement new operator is used to create a new House in exactly the same space in memory as the old one, using the default copy constructor so that all the const variables are (re)initialized. Finally, a technicality for all assignment operators, a reference to the object is returned. (This is so C-style expressions like "var1 = var2 = var3 = 5;" can be used.) Now, this works beautifully on my VC++. But... is it legal C++?? Am I entering the realm of "undefined behavior", or is this a perfectly legitimate technique? Is there an obviously better solution to my problem? Are there caveats that I should be looking out for? Please, someone with more knowledge of the C++ standards, give me a hand here. Thanks! -Jonathan

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RE: [Boost-Users] Class destructor invocation - possible by hand ?
by Tom Matelich 17 Jan '02

17 Jan '02

> > > > Also, I would recommend that you either reconsider > > > having the constant member variable, or use a > > > vector<>. > > > > Using a vector<T> won't work in this case, because the STL uses > > T::operator = in order to copy vector contents into new > locations during > > memory reallocation. And there's no logical way to > implement operator = > > when a const data member is present, which is the cause of this > > conversation. > > I could use std::list, since it doesn't do reallocation, but clients > > using this class in containers will most likely need random access > > iterators. > > > > Any other ideas? > > Easy option: Use a vector<shared_ptr<T> >. This will give you > basically > the behavior you want, with the ability to initialize the elements > directly. The drawback is that the data will be dynamically allocated. Another drawback is the interface is now pointers, not references. If you don't mind the dynamic allocation, the vector<shared_ptr<T> > can be contained by another class, overloading operator[], etc. The Boost Iterator Adapter library works very nicely for providing vector<T>::iterator behavior from a vector<shared_ptr<T> >::iterator. I can send you our vector-like class which uses adapted iterators if you would like. Re: the moderation. Yes, this is not a boost question, but it is a question boost can provide good solutions for, so where do you draw the line?

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