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BoostCon 2007 Call for Proposals
by Beman Dawes 30 Sep '06

30 Sep '06

The first annual Boost conference will take place in Aspen, Colorado, May 14-18, 2007. BoostCon 2007 is looking for session presenters. We invite you to propose a session. For details on how to become a presenter, see www.boost.org/more/BoostCon07_session_call.html This inaugural Boost conference promises to be the main face-to-face venue for all things Boost, from using libraries to writing them, from evangelizing Boost to deployment within your organization, from infrastructure and process to vision and mission, and from TR1 to TR2. Given the range and interests of the participants, the event is going to be intense and in-depth. For more information about the conference, see www.boost.org/more/BoostCon07.html --The Organizing Committee David Abrahams Beman Dawes Jeff Garland Joel de Guzman Kevlin Henney Howard Hinnant Scott Meyers Eric Niebler Sean Parent Rene Rivera Jeremy Siek Matthias Troyer

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Fwd: boost regex library problem with release build
by Maggie Nguyen 30 Sep '06

30 Sep '06

I fixed the problem. For debug: my project setting as: C/C++ > Code Generation > Runtime LIbrary as "Multi-threaded DLL (/MD)" But in my release setting: C/C++ > Code Generation > Runtime LIbrary as "Multi-threaded (/MT)" When I changed it to "Multi-threaded DLL (/MD)", then it works! As indicated in the boost/boost/config/user.hpp, which needs _DLL flag. Thanks, Maggie ---------- Forwarded message ---------- From: maggie.nguyen(a)gmail.com <maggie.nguyen(a)gmail.com> Date: Sep 29, 2006 9:45 AM Subject: boost regex library problem with release build To: Hi, I use Visual Studios 2005. In my project file, I include the library in linker: "Additional Library Directories: ..\..\boost\lib" I have these libs in the boost\lib directory: libboost_date_time-vc80-mt-1_33_1.lib libboost_date_time-vc80-mt-gd-1_33_1.lib libboost_regex-vc80-mt-1_33_1.lib libboost_regex-vc80-mt-gd-1_33_1.lib libboost_thread-vc80-mt-1_33_1.lib libboost_thread-vc80-mt-gd-1_33_1.lib When I build my project as a debug build. it compiles fine. However, if I change to release build, it gives me this error: Error 1 fatal error LNK1104: cannot open file 'libboost_regex-vc80-mt-s-1_33_1.lib' Please let me know what I need to do to have it point to "libboost_regex-vc80-mt-1_33_1.lib" instead of "libboost_regex-vc80-mt-s-1_33_1.lib". Thanks very much, Maggie

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boost regex library problem with release build
by Maggie Nguyen 29 Sep '06

29 Sep '06

Hi, I use Visual Studios 2005. In my project file, I include the library in linker: "Additional Library Directories: ..\..\boost\lib" I have these libs in the boost\lib directory: libboost_date_time-vc80-mt-1_33_1.lib libboost_date_time-vc80-mt-gd-1_33_1.lib libboost_regex-vc80-mt-1_33_1.lib libboost_regex-vc80-mt-gd-1_33_1.lib libboost_thread-vc80-mt-1_33_1.lib libboost_thread-vc80-mt-gd-1_33_1.lib When I build my project as a debug build. it compiles fine. However, if I change to release build, it gives me this error: Error 1 fatal error LNK1104: cannot open file 'libboost_regex-vc80-mt-s-1_33_1.lib' Please let me know what I need to do to have it point to "libboost_regex-vc80-mt-1_33_1.lib" instead of "libboost_regex-vc80-mt-s-1_33_1.lib". Thanks very much, Maggie

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How to build boost on aix with vacpp ?
by Parmentier Jean-Luc (DBB) 29 Sep '06

29 Sep '06

Hi, I want to use boost on ibm-aix with VisualAge C++ Professional / C for AIX Compiler, Version 6 To do this: - I downloaded the version 1.33.1 of boost on sourceforge - I used the following configure statement to build the makefile configure --with-toolset=vacpp - I launched the make statement to build the libraries. But I encountered the following message during make process xlc-C++-action bin/boost/libs/regex/build/libboost_regex.so/vacpp/debug/cregex.o "/TST/FIED/murex/flex/boost_1_33_1/boost/regex/v4/regex_traits.hpp", line 80.1: 1540-1269 (S) The template argument for the non-type template parameter of type "bool" must be an integral constant expr ession. "/TST/FIED/murex/flex/boost_1_33_1/boost/regex/v4/regex_traits.hpp", line 159.36: 1540-0700 (I) The previous message was produced while processing "struct boost::re_detail::has_boost_extensions_tag<bo ost::regex_traits<char,boost::cpp_regex_traits<char> >,mpl_::bool_<0> >". xlc -c -I/TST/FIED/murex/flex/boost_1_33_1 -DBOOST_REGEX_CONFIG_INFO=1 -DBOOST_REGEX_DYN_LINK=1 -qNOOPTimize -qnoinline -g -qfullpath -qnotempinc -qfuncsect -qeh -qrtti -I"bin/boost/libs/reg ex/build" -I"/TST/FIED/murex/flex/boost_1_33_1" -o "bin/boost/libs/regex/build/libboost_regex.so/vacpp/debug/cregex.o" "/TST/FIED/murex/flex/boost_1_33_1/libs/regex/build/../src/cregex.cpp" ...failed xlc-C++-action bin/boost/libs/regex/build/libboost_regex.so/vacpp/debug/cregex.o... Any hints for resolving this would be appreciated. Thanks in advance. -------------------------------------- Dexia Bank disclaimer : http://www.dexia.be/maildisclaimer.htm --------------------------------------

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Including boost headers with MPL OSS project?
by Moritz Moeller 29 Sep '06

29 Sep '06

Hey, we like to use some of the smart pointer stuff in Liquid (liquidmaya.sf.net) However, we like to avoid a boost dependency as that stuff is just headers. We were thus wondering if there were any problems if we included the resp. headers with the Liquid source. Liquid is released under the MPL. Rather surprisingly, none of us liquid developers has a background in law. :> Hence we are unsure if the boost license permits distributing the headers. I guess if we added the boost license and stated that those headers lived under that license that might be ok? Or does the license not permit to distribute any part of boost but only the whole shebang? Thanks in advance for any feedback on this! Cheers Moritz -- moritz moeller bloody german td -- moritz.moeller(a)rsp.com.au ---------------------------------------------------------------- rising sun pictures -- www.rsp.com.au ---------------------------------------------------------------- direct line +61 2 9338 6458 mobile ph +61 405 372 249 ---------------------------------------------------------------- adl ph +61 8 8400 6400 -- fx +61 8 8400 6401 level 1, 133 gouger street, adelaide, 5000 ---------------------------------------------------------------- syd ph +61 2 9338 6400 -- fx +61 2 9338 6401 15/16 charles street, redfern, sydney, 2016 ---------------------------------------------------------------- rising sun research -- www.risingsunresearch.com ----------------------------------------------------------------

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BOOST_AUTO_UNIT_TEST and command-line options
by Rob Caldecott 29 Sep '06

29 Sep '06

I have a test program that uses the BOOST_AUTO_UNIT_TEST macro (in conjunction with BOOST_AUTO_TEST_MAIN), which has been working well. However, I now need to pass some options to my test program on the command-line and the only way I can see to do this is to drop BOOST_AUTO_TEST_MAIN, add the init_unit_test_suite function and register all my tests "by hand". Is there any way to process my command-line options without losing the AUTO functionality? Thanks in advance.

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Cannot connect to boost repository via TortoiseSVN client
by alexmark 29 Sep '06

29 Sep '06

Hi! What is the actual URL of main boost repository? I need read-only access. Thanks.

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boost message passing
by Levent Yilmaz 29 Sep '06

29 Sep '06

Hi Boosters! In this post I just wanted to throw in my two cents about the newly accepted MPI library, from a luser's point of view. (doc: http://tinyurl.com/fjc9x) It was a great excitement to see the news on boost.org "Message Passing Review Begins"! The C bindings of MPI are a great pain to use -- a fact which is mostly denied by programmers who are unaware of C++'s beauty and content with even good old F77 most of the time. And, as it has been pointed out by Boost.MPI developers, the C++ bindings of standard MPI, though an improvement, are nothing more than simple wrappers on top of the C bindings. Moreover, certain supercomputing centers do not even have these C++ bindings of MPI installed on their otherwise state-of-the-art clusters. So, anyway, it was great to hear that finally MPI will be *boost*ed. There is a lot to what is good about this new boost library. For one, quoting Jeremy: "One particularly nice aspect of Boost.MPI is the way it leverages the Boost serialization library". This indeed appears to be a greatly elegant way to message-pass user types around. There are other features to applaud, such as reduce() via arbitrary functors. Yet, in this post, with the intent of providing constructive criticism, I'd like to point out several design issues related to the user interface; mostly in comparison with other MPI implementations. (hereafter the discussion will assume specific knowledge about MPI) Here is a brief outline of what I'll be talking about, somewhat in the order of importance: 1. Port object 2. Message object 3. Skeleton and content questions 4. MPI-2 bindings *Port Object* Those of you who have actively programmed with MPI certainly have used or at least heard of the OOMPI library (I believe Doug Gregor, one of the two developers of Boost.MPI, is affiliated with the institution OOMPI was born). Its web page, http://www.osl.iu.edu/research/oompi/ , greets you with random (mostly funny) messages, such as "OOMPI- Isn't it time you did something for YOU?" :) Anyway, it was thanks to OOMPI library that I realized that in fact MPI programming could be fun! Especially, there is this *OOMPI_Port* abstraction that literally _enlighten_s the way point-to-point (PTP) and rooted-collective (RC) operations are made. Let's contrast the way PTP is carried out for the three interfaces (Standard MPI, Boost.MPI and OOMPI): //================================================\\ // Standard way int rank; MPI_Comm_rank(MPI_COMM_WORLD, &rank); int msg; int msg_tag = 10; if (rank == 0) { msg = 17; MPI_Send(&msg, 1, MPI_INT, 1, msg_tag, MPI_COMM_WORLD); // (synopsis: http://tinyurl.com/ejmgg ) } elseif (rank==1) { MPI_Recv(&msg, 1, MPI_INT, 0, msg_tag, MPI_COMM_WORLD, MPI_STATUS_IGNORE); // (synopsis: http://tinyurl.com/elkez ) } // Boost.MPI way mpi::communicator world; int msg; int msg_tag = 10; if (world.rank() == 0) { msg = 17; world.send(1, msg_tag, msg); } elseif (world.rank() == 1) { world.recv(0, msg_tag, msg); } // OOMPI way OOMPI_Comm_world& world = OOMPI_COMM_WORLD; world.Init(argc,argv); int msg; int msg_tag = 10; OOMPI_Port to (world[1]); OOMPI_Port from (world[0]); if (world.Rank() == from.Rank()) { msg = 17; to.Send(msg,msg_tag); } else if (world.Rank() == to.Rank()) { from.Recv(msg,msg_tag); } //============================================= The standard C provides global functions for this simplest and most commonly employed Send/Recv commands. These functions require a long list of arguments, which are usually a pain to keep track of (here is another P2P command which is really harsh http://tinyurl.com/mk6dq) Also, such an interface does not provide any conceptual description of what is going on. The design of MPI is indeed mostly object oriented (http://tinyurl.com/qm9hd) however the implementation doesn't realize this fact. Boost.MPI improves two aspects of this: For one the P2P commands are member functions of the communicator (same as the standard C++ bindings); and two, the message's type is templated and the user does not have to repeatedly specify what she is sending. But, as in C-version, one still has to realize the points (P's in P2P) of communication as a bunch of integer values rather than, well, the points of communication, which are an entities by themselves. OOMPI takes this one step further and things kind of fit in place with the whole framework of MPI's design: The points of communication are objects themselves, abstracted as OOMPI_Port class. P2P functions are member functions of OOMPI_Port and OOMPI_Port is in turn a certain piece of a given communicator. Here is how an RC communication looks like: //============================================= // Root-collective communication with OOMPI. // The message will be created at the 4th process and //+ will be broadcasted to everyone in the world communicator. OOMPI_Port root = world[4]; root.Bcast(msg); // or if the Port will not be used for anything else, it is //+ possible to create a temporary: world[4].Bcast(msg); // Here is how this is with Boost.MPI broadcast(world, msg, 4); //============================================= Clearly the OOMPI version is more instructive of the communication process. A more elaborate illustration can be given in the context of communication topologies (a feature that is not yet available in Boost.MPI, unless I am mistaken). For instance: //============================================= // Create a cartesian virtual topology enum {X,Y,NDIM}; int shape[NDIM] = {3,2}; // requires world.size() >= 6; bool is_periodic[] = {true,true}; OOMPI_Cart_comm grid(world,NDIM,shape,is_periodic); // Get nodes of subsequent P2P communication OOMPI_Port left = grid[grid.Shift(X,-1)]; // left neighbor OOMPI_Port right = grid[grid.Shift(X, 1)]; // right neighbor // get cartesian coordinates int mycoords[NDIM]; grid.Coords(mycoords); // create a message int msg = grid.Rank(); // P2P communicate left.Send(msg); // send to left right.Recv(msg); // recv from right //================================================ I wonder why this Port abstraction (or a similar idea) couldn't make its way to Boost.MPI? Is there an underlying design decision to this? Also, why the P2P commands are members of the communicator class but RC commands such as broadcast and gather are global? *Message object* A message in MPI is created by specifiying a data type, data count, data address and finally a message tag. Note the C interface of passing a message in a P2P communication (see first example above). The 4 out of 6 arguments in MPI_Send() is just to specify the message. And for every communication statement of the same kind, this list should be repeated. Boost.MPI (ignoring the skeleton/content idea for a second) reduces this to three arguments (http://tinyurl.com/k2w7q) Reference to the data (from which the type is deduced), data count and the message tag. However, this message is still not a separate entity; and all this information is repeatedly specified as arguments to communication functions. OOMPI provides the convenience of OOMPI_Message object, which is then used in communications. For instance, to pass an array of integers: //============================================= int size = 5; int arr[size]; OOMPI_Tag msg_tag = 10; OOMPI_Message msg(arr1,size,msg_tag); if (world.Rank() == root.Rank()) /* fill up the arr */; root.Bcast(msg); //============================================= *Skeleton and Content - Separating structure from content* Boost.MPI provides this promising functionality which not only simplifies message specifications during communication calls but also helps to easily create more complex data types. But as admittedly a naive user, I am not so sure if this won't actually degrade the performance, or why is this even necessary at all. For instance, let's examine the example given here (http://tinyurl.com/mgwkt) A plain C implementation of the same thing would be something like this: //=================================================== int root = 0; // Create the message type (this section of the //+ code is run by ALL processes in the communicator). int list_len = 10; // size of the message std::list<int> mylist(list_len); std::vector<int*> data_locations(list_len); std::vector<int > block_lengths(list_len,1); using boost::lambda::_1; std::transform( mylist.begin(), mylist.end(), data_locations.begin(), &_1); MPI_Datatype msg_type; MPI_Type_hindexed(list_len, &block_lengths[0], reinterpret_cast<MPI_Aint*>(&data_locations[0]), MPI_INT, &msg_type); MPI_Type_commit(&msg_type); // fill with useful data in the master node if (world.Rank() == root ) std::generate(mylist.begin(),mylist.end(),&std::rand); // distribute the data MPI_Bcast(MPI_BOTTOM,1,msg_type,0,MPI_COMM_WORLD); //==================================================== What is happening here is that, initially each process creates in its own address space, a list of some pre-specified size that is equal in every process. Then a local _definition_ of the container is created as a collection of addresses of every element in the list. A type is then associated with this list to be used in subsequent message passing calls. The root node fills up the list in its own memory space with useful data, and via a broadcast call (a rooted-collective call) message-passes the values to other slave processes. The slave processes gathers the received data into their own list, which is specified by the local type that has just been created. As a matter of fact, the slaves might have gathered the whole data into a vector of ints if they so pleased (and this is usually more efficient since underlying MPI implementation already receives the data as a consequtive chunk of values before processing it with the specified MPI_Datatype). Now, Boost.MPI conveniently reduces the data type definition down to a single statement: mpi::skeleton(mylist); But, then the example has this extra broadcasting statement (indeed, the example is such that the skeleton (MPI_Datatype) is created as a temporary): broadcast(world, mpi::skeleton(mylist), 0); Here, I am not so sure why this is useful. The only thing that is common with the master and slave processes' lists is the list_len, which is already assumed to be known by all. The containers live in totally distinct memory spaces and the elements are located at different addresses. So everybody has to call mpi::skeleton(mylist) separately, but not _receive_ it from the master. The actual data is passed by subsequent possibly multiple broadcast calls: mpi::content c = mpi::get_content(l); broadcast(world, c, root); Now, here is the content anything more than MPI_BOTTOM? What extra information does it carry? Is it possible to apply the same skeleton to a different list<int> of same size? Another point, as I indicated before with the C example, is it possible to create skeletons of different containers of the same value_type (say list<int> on master and vector<int>'s on slaves) and pass the contents around without performance penalty? *MPI-2 Bindings* Somewhere in the documentation a reference to MPI-2 bindings has been made (http://tinyurl.com/jhjo8) Including modern MPI-2 bindings are of course an important provision; however as I indicated previously, there are certain supercomputing centers which do not support MPI-2 yet. Does this resctrict the usage of Boost.MPI in anyway? In other words, would my code still compile and link if I avoid the MPI-2 subset of Boost.MPI? To conclude my rather huge post, I was expecting perhaps Boost.MPI to be a *boost*ed OOMPI implementation (for instance OOMPI does have a lot of disturbing issues especially related to user data types), that amplifies the elegant abstractions while incurring minimum performance penalty. A lot of work has been put into the user type manipulations and it is exciting to see the serialization library in such good use. However, with the essentials such as the communication statements, Boost.MPI does not seem to add much on top of the standard MPI C++ bindings. Also, as indicated by the developers themselves, the current implementation supports only a limited subset of MPI 1.1. Yet, IMHO, given this subset doesn't even include the virtual topology creation, it is perhaps a bit too early to have it in boost. Well, thanks for bearing with me this far. I hope I was able to provide useful feedback for this fresh library. - Levent

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[BGL] binary heap
by moritz Hilger 29 Sep '06

29 Sep '06

hi, what happend to the binary-heap implementation in the bgl? as i can tell from older posts on the mailinglist there used to be one which was replaced by the relaxed-heap-implementation for performance reasons. nevertheless afaik the theoretical advantage of fibonacci heaps (and, probably, the relaxed heap) does not hold for some real-world problems. any chance of re-integrating alternative heap-structures for comparison reasons? cheers moritz

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Failed building Boost using MinGW
by Andre Tampubolon 29 Sep '06

29 Sep '06

So here's the scenario : - My MinGW directory is C:\mingw (don't put it at the PATH, because of Cygwin) - My Boost directory is C:\mingw\msys\1.0\home\Administrator\boost_1_33_1 So I put the bjam.exe in the Boost directory then invoke : bjam -sMINGW_ROOT_DIRECTORY=c:\mingw\ stage And an error message box "bjam.exe has encountered a problem and needs to close..." appers. Any solution ? --------------------------------- All-new Yahoo! Mail - Fire up a more powerful email and get things done faster.

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create threads from within a class
by Monica Gretzer 29 Sep '06

29 Sep '06

Hi, I want to use boost::thread to create threads that are member functions within a class. In all the examples I have seen, the thread function is defined globally. I explain it with code. The following test code works: // code 1: example program that works ----------------------------------------------- #include <boost/thread/thread.hpp> #include <iostream> using namespace std; void testing() { cout << "I'm a thread." << endl; } int main(int argc, char* argv[]) { // start a new thread that calls the "testing" function boost::thread my_thread(&testing); // wait for the thread to finish my_thread.join(); return 0; } // ------------------------------------------------------------------------------------------- Now, I want to create something like: // code 2: thread created from member class (code yields compiler errors) #include <boost/thread/thread.hpp> #include <iostream> using namespace std; class TestThread { public: void testing(void); void CreateThread(void); }; void TestThread::CreateThread() { // start a new thread that calls the "testing" function boost::thread my_thread(&testing); // wait for the thread to finish my_thread.join(); } int main(int argc, char* argv[]) { TestThread t; t.CreateThread(); return 0; } When compiling the code above (code 2), I get the following compilation error: ISO C++ forbids taking the address of an unqualified or paranthesized non-static member function to form a pointer to member function. Say &TestThread::testing. My question is: How do I create threads from within a C++ class member function? Thanks a lot for your help. / Mogr

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Re: [Boost-users] [serialization] How to serialize an object usingareference to its base class ?
by x y 29 Sep '06

29 Sep '06

#include <string> #include <sstream> #include <iostream> #include <boost/archive/xml_oarchive.hpp> #include <boost/archive/xml_iarchive.hpp> #include <boost/archive/binary_oarchive.hpp> #include <boost/archive/binary_iarchive.hpp> #include <boost/archive/text_oarchive.hpp> #include <boost/archive/text_iarchive.hpp> #include <boost/serialization/string.hpp> #include <boost/serialization/access.hpp> #include <boost/serialization/is_abstract.hpp> #include <boost/serialization/export.hpp> using namespace std; class base_class { friend class boost::serialization::access; public: base_class() : my_string("") { }; base_class(string s) : my_string(s) { }; virtual ~base_class() {}; virtual void foo(void) = 0; template<class Archive> void serialize(Archive & ar, const unsigned int version) { ar & BOOST_SERIALIZATION_NVP(my_string); } public: string my_string; }; BOOST_IS_ABSTRACT(base_class); BOOST_CLASS_EXPORT(base_class); class derived_class : public base_class { friend class boost::serialization::access; public: derived_class() : base_class(), my_int(0) {}; derived_class(string s, int i) : base_class(s), my_int(i) {}; virtual ~derived_class() {}; void foo(void) {}; template<class Archive> void serialize(Archive & ar, const unsigned int version) { ar & BOOST_SERIALIZATION_BASE_OBJECT_NVP(base_class) & BOOST_SERIALIZATION_NVP(my_int); } int my_int; }; BOOST_CLASS_EXPORT(derived_class); void serialize(const base_class* src, std::ostream& dest) { // boost::archive::xml_oarchive oa(dest); boost::archive::binary_oarchive oa(dest); oa << BOOST_SERIALIZATION_NVP(src); } int main(int argc, char** argv) { try { stringstream ss; derived_class d("aaa", 5); cout << "before: " << d.my_string << " " << d.my_int << endl; serialize(&d, ss); derived_class d2; // boost::archive::xml_iarchive ia(ss); boost::archive::binary_iarchive ia(ss); ia >> BOOST_SERIALIZATION_NVP(d2); cout << "after: " << d2.my_string << " " << d2.my_int << endl; } catch (const std::exception& ex) { cout << "std exception: " << ex.what() << endl; } catch (...) { cout << "unknown exception" << endl; } return 0; } ----- Original Message ---- From: Robert Ramey <ramey(a)rrsd.com> To: boost-users(a)lists.boost.org Sent: Thursday, September 28, 2006 3:12:45 PM Subject: Re: [Boost-users] [serialization] How to serialize an object usingareference to its base class ? Without seeing your program I couldn't suggest much. Robert Ramey "x y" <nosferatu_1_1(a)yahoo.com> wrote in message news:20060928094242.89373.qmail@web31010.mail.mud.yahoo.com... It works now, but only with XML archives. When I serialize into a binary archive I get a std::exception "bad alloc exception thrown". I forgot to mention that I'm working with Borland C++ Builder 6, boost 1_33_0 I also tried with gcc 3.2.3 on linux with boost 1_33_1 and it also works only with xml archives. With binary archive I get a "basic_string::resize" exception. Robert Ramey <ramey(a)rrsd.com> wrote: This works for pointers - not references. - the following - along with compatible changes - should work. Robert Ramey void serialize(const base_class * src, std::ostream& dest) { boost::archive::binary_oarchive oa(dest); oa << BOOST_SERIALIZATION_NVP(src); } "x y" <nosferatu_1_1(a)yahoo.com> wrote in message news:20060927081505.10666.qmail@web31012.mail.mud.yahoo.com... Hi, I'm new to boost and I'm having some trouble serializing an object using a reference to its base class. Although there are a lot of messages related to this topic in the newsgroups and the doc, I did not find a workable answer to my proplem. In the following code, the function serialize takes a reference to base_class as parameter. But the serialize method of derived_class is never called. Did I miss something ? Thanks for your help Marc #include <string> #include <sstream> #include <iostream> #include <boost/archive/binary_oarchive.hpp> #include <boost/archive/binary_iarchive.hpp> #include <boost/serialization/string.hpp> #include <boost/serialization/access.hpp> #include <boost/serialization/is_abstract.hpp> #include <boost/serialization/export.hpp> using namespace std; class base_class { friend class boost::serialization::access; public: base_class() : my_string("") { }; base_class(string s) : my_string(s) { }; virtual ~base_class() {}; virtual void foo(void) = 0; template<class Archive> void serialize(Archive & ar, const unsigned int version) { ar & BOOST_SERIALIZATION_NVP(my_string); } public: string my_string; }; BOOST_IS_ABSTRACT(base_class); BOOST_CLASS_EXPORT(base_class); class derived_class : public base_class { friend class boost::serialization::access; public: derived_class() : base_class(), my_int(0) {}; derived_class(string s, int i) : base_class(s), my_int(i) {}; virtual ~derived_class() {}; void foo(void) {}; template<class Archive> void serialize(Archive & ar, const unsigned int version) { ar & BOOST_SERIALIZATION_BASE_OBJECT_NVP(base_class) & BOOST_SERIALIZATION_NVP(my_int); } int my_int; }; BOOST_CLASS_EXPORT(derived_class); void serialize(const base_class& src, std::ostream& dest) { boost::archive::binary_oarchive oa(dest); oa << BOOST_SERIALIZATION_NVP(src); } int main(int argc, char** argv) { try { std::stringstream ss; derived_class d("aaa", 5); cout << "before: " << d.my_string << " " << d.my_int << endl; serialize(d, ss); // deserialize derived_class d2; boost::archive::binary_iarchive ia(ss); ia >> d2; cout << "after: " << d2.my_string << " " << d2.my_int << endl; } catch (const std::exception& ex) { cout << "std exception: " << ex.what() << endl; } catch (...) { cout << "unknown exception" << endl; } } Talk is cheap. Use Yahoo! Messenger to make PC-to-Phone calls. Great rates starting at 1¢/min. _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users Talk is cheap. Use Yahoo! Messenger to make PC-to-Phone calls. Great rates starting at 1¢/min. _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users _______________________________________________ Boost-users mailing list Boost-users(a)lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users

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[Filesystem] File Rename issue
by Andrei Danaila 28 Sep '06

28 Sep '06

Hi, I have some trouble with a file renaming program i wrote. The program is supposed to recursively traverse a folders in search for a file, and rename the file to the name of the folder. The program, traverses all the folders successfully, but when i try the rename command i get the following compile error "error C2039: current_path is not a member of 'path', see declaration of path. c:\boost\include\boost-1_33_1\boost\filesystem\path.hpp I am aware that the current_path() function is not included in path.hpp however the object that i am trying to use it on is a directory _iterator and as such should work. I am new to all of this stuff, any advice would be appreciated, Below is the very non elegant source code with the problem highlighted close to the end of the code. int i=0; namespace fs = boost::filesystem; bool recursiveList(fs::path); int main() { fs::path fullPath("test2"); recursiveList(fullPath); std::cout<<"Number of files = "<<i<<"\n"; return 0; } bool recursiveList(fs::path givenPath) { char iteration=0; std::string directoryName="failed"; fs::directory_iterator end_iter; fs::directory_iterator start_iter(givenPath); fs::directory_iterator restart_Path(givenPath); int numberOfFiles=0; givenPath=fs::system_complete(givenPath); std::cout<<"The full path is: "<<givenPath.native_directory_string()<<"\n\n"; for (; start_iter!=end_iter; ++start_iter) { if ( fs::is_directory(*start_iter)) { std::cout<<start_iter->leaf()<<"[directory]\n\n"; directoryName=start_iter->leaf(); recursiveList(*start_iter); ; } else { std::cout<<start_iter->leaf()<<"[file]\n\n"; i++; numberOfFiles++; } } for (int j=0;j<numberOfFiles;j++,restart_Path++) { if(!fs::is_directory(*restart_Path)) { if (numberOfFiles==1) { std::cout<<"Multiple Files detected, attempting rename with iterations\n"; std::cout<<"Attempting Name Change...\n"; std::cout<<"Present Name: "<<restart_Path->leaf()<<"\n"; std::cout<<directoryName; //PROBLEM HERE!!!!! //***************************************************** fs::rename(restart_Path->current_path(),directoryName); //***************************************************** } } } return true; }

1 0

[serialization] How to serialize an object using a reference to its base class ?
by x y 28 Sep '06

28 Sep '06

Hi, I'm new to boost and I'm having some trouble serializing an object using a reference to its base class. Although there are a lot of messages related to this topic in the newsgroups and the doc, I did not find a workable answer to my proplem. In the following code, the function serialize takes a reference to base_class as parameter. But the serialize method of derived_class is never called. Did I miss something ? Thanks for your help Marc #include <string> #include <sstream> #include <iostream> #include <boost/archive/binary_oarchive.hpp> #include <boost/archive/binary_iarchive.hpp> #include <boost/serialization/string.hpp> #include <boost/serialization/access.hpp> #include <boost/serialization/is_abstract.hpp> #include <boost/serialization/export.hpp> using namespace std; class base_class { friend class boost::serialization::access; public: base_class() : my_string("") { }; base_class(string s) : my_string(s) { }; virtual ~base_class() {}; virtual void foo(void) = 0; template<class Archive> void serialize(Archive & ar, const unsigned int version) { ar & BOOST_SERIALIZATION_NVP(my_string); } public: string my_string; }; BOOST_IS_ABSTRACT(base_class); BOOST_CLASS_EXPORT(base_class); class derived_class : public base_class { friend class boost::serialization::access; public: derived_class() : base_class(), my_int(0) {}; derived_class(string s, int i) : base_class(s), my_int(i) {}; virtual ~derived_class() {}; void foo(void) {}; template<class Archive> void serialize(Archive & ar, const unsigned int version) { ar & BOOST_SERIALIZATION_BASE_OBJECT_NVP(base_class) & BOOST_SERIALIZATION_NVP(my_int); } int my_int; }; BOOST_CLASS_EXPORT(derived_class); void serialize(const base_class& src, std::ostream& dest) { boost::archive::binary_oarchive oa(dest); oa << BOOST_SERIALIZATION_NVP(src); } int main(int argc, char** argv) { try { std::stringstream ss; derived_class d("aaa", 5); cout << "before: " << d.my_string << " " << d.my_int << endl; serialize(d, ss); // deserialize derived_class d2; boost::archive::binary_iarchive ia(ss); ia >> d2; cout << "after: " << d2.my_string << " " << d2.my_int << endl; } catch (const std::exception& ex) { cout << "std exception: " << ex.what() << endl; } catch (...) { cout << "unknown exception" << endl; } } --------------------------------- Talk is cheap. Use Yahoo! Messenger to make PC-to-Phone calls. Great rates starting at 1¢/min.

2 3

[Serialization]: SIGSEGV on Mingw32, during global static data initialization (runs ok on Linux)
by Jeffrey Chang 28 Sep '06

28 Sep '06

Hi, I've been using boost Serialization library (release v1_33_1) on Linux without problems, with g++ compiler of both v3.3.6 & v4.1.1. My program serialzes boost::shared_ptr of polymorphic types, and BOOST_CLASS_EXPORT() and BOOST_SERIALIZATION_SHARED_PTR() are used. However, when the same program is ported & run on mingw32 (w/ g++ v3.4.5 on WinXP), it generates SIGSEGV before my main() is called. and here's the stack trace: Program received signal SIGSEGV, Segmentation fault. 0x6e3759a3 in boost::archive::detail::basic_serializer::basic_serializer ( this=0x4, eti=@0x813484) at /opt/boost/boost_1_33_1/boost/archive/detail/basic_serializer.hpp:37 37 {} (gdb) bt #0 0x6e3759a3 in boost::archive::detail::basic_serializer::basic_serializer ( this=0x4, eti=@0x813484) at /opt/boost/boost_1_33_1/boost/archive/detail/basic_serializer.hpp:37 #1 0x6e34220b in boost::archive::detail::basic_oserializer::basic_oserializer (this=0x0, eti=@0x813484) at /opt/boost/boost_1_33_1/libs/serialization/build/../src/basic_oserializer.cpp:24 #2 0x005fb394 in boost::archive::detail::pointer_oserializer<HmcBase, boost::archive::text_oarchive>::pointer_oserializer (this=0x813164) at /opt/boost/boost_1_33_1/boost/serialization/extended_type_info_typeid.hpp:95 #3 0x00477c12 in __static_initialization_and_destruction_1 ( __initialize_p=8467588, __priority=65535) at /opt/boost/boost_1_33_1/boost/archive/detail/oserializer.hpp:198 #4 0x004c5a57 in __main () at /opt/boost/boost_1_33_1/boost/archive/detail/oserializer.hpp:198 #5 0x00404568 in main (argc=1, argv=0x3d45f8) at ../../src/HmcMain.cpp:231 (gdb) I cannot connect the logic between stack frame #3 and #2; it seems trying to instantiate some global static data when SIGSEGV happens. Is there some dependency on order of global static data initialization to be satisfied for using BOOST_CLASS_EXPORT/BOOST_SERIALIZATION_SHARED_PTR? HmcBase is the base class for my polymorphic types, and all my code are statically linked, while "boost_serialization-mgw-d-1_33_1.dll" is used here. I saw some discussion in this mailing list on "Serializing classes defined in DLLs"<http://news.gmane.org/find-root.php?message_id=%3c432FF0C3.5010002%40intopi…>a year ago, but don't know what's the current status on it and whether this case is related to it. Thanks for any hit, --- Jeffrey

2 7

boost-sandbox releases on sf.net
by Markus Werle 28 Sep '06

28 Sep '06

Hi! This is me sitting behind a virtual fence that hinders cvs access to the boost-sandbox. Fetching all the files by hand via web-interface is a no-go. Could someone be so nice and provide weekly snapshots of the sandbox from the download page at sf.net? regards, Markus

1 0

Re: [Boost-users] [Graph] find cycles
by Sohail Somani 27 Sep '06

27 Sep '06

> -----Original Message----- > From: boost-users-bounces(a)lists.boost.org > [mailto:boost-users-bounces@lists.boost.org] On Behalf Of > Michele Russo > Sent: Wednesday, September 27, 2006 12:52 AM > To: boost-users(a)lists.boost.org > Subject: [Boost-users] [Graph] find cycles > > Hi all, > > Please, couold you suggest me a simple way to find a cycle > into a graph (just a sentence, no code)? What about the > computational complexity? In a sentence: DFS.

1 0

[Graph] find cycles
by Michele Russo 27 Sep '06

27 Sep '06

Hi all, Please, couold you suggest me a simple way to find a cycle into a graph (just a sentence, no code)? What about the computational complexity? Best regards, Michele __________________________________________________ Do You Yahoo!? Poco spazio e tanto spam? Yahoo! Mail ti protegge dallo spam e ti da tanto spazio gratuito per i tuoi file e i messaggi http://mail.yahoo.it

2 1

Using boost::lambda on AIX with xlC version 6
by Jerry Jeremiah 26 Sep '06

26 Sep '06

> Hello, I would appreciate any help with this. I am trying to compile this test program on AIX with xlC (VisualAge C++ Professional / C for AIX Compiler, Version 6): #include <iostream> // cout #include <vector> // vector #include <algorithm> // for_each #include "boost/lambda/lambda.hpp" using namespace boost::lambda; main() { std::vector<int> a; a.push_back(1); std::for_each(a.begin(), a.end(), std::cout << _1 << ' '); } And I get: "./boost/lambda/detail/operator_lambda_func_base.hpp", line 212.1: 1540-0219 (S) The call to "detail::select" has no best match. "./boost/lambda/detail/operator_lambda_func_base.hpp", line 212.1: 1540-1228 (I) Argument number 1 is an lvalue of type "const boost::lambda::lambda_functor<boost::lambda::lambda_functor_base<boost::lambda: :bitwise_action<boost::lambda::leftshift_action>,boost::tuples::tuple<std::basi c_ostream<char,std::char_traits<char> > &,boost::lambda::lambda_functor<boost::lambda::placeholder<1> >,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,bo ost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost: :tuples::null_type,boos...". "./boost/lambda/detail/operator_lambda_func_base.hpp", line 212.1: 1540-1228 (I) Argument number 2 is an lvalue of type "int". "./boost/lambda/detail/operator_lambda_func_base.hpp", line 212.1: 1540-1228 (I) Argument number 3 is an lvalue of type "const boost::tuples::null_type". "./boost/lambda/detail/operator_lambda_func_base.hpp", line 212.1: 1540-1228 (I) Argument number 4 is an lvalue of type "const boost::tuples::null_type". "./boost/lambda/detail/operator_lambda_func_base.hpp", line 212.1: 1540-1228 (I) Argument number 5 is an lvalue of type "const boost::tuples::null_type". "./boost/lambda/detail/select_functions.hpp", line 27.1: 1540-1202 (I) No candidate is better than "boost::lambda::detail::select<boost::lambda::lambda_functor_base<boost::l ambda::bitwise_action<boost::lambda::leftshift_action>,boost::tuples::tuple<std ::basic_ostream<char,std::char_traits<char> > &,boost::lambda::lambda_functor<boost::lambda::placeholder<1> >,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,bo ost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost: :tuples::null_type,boost::tuples::null_type>...". "./boost/lambda/detail/operator_lambda_func_base.hpp", line 212.1: 1540-1231 (I) The conversion from argument number 1 to "const boost::lambda::lambda_functor<boost::lambda::lambda_functor_base<boost::lambda: :bitwise_action<boost::lambda::leftshift_action>,boost::tuples::tuple<std::basi c_ostream<char,std::char_traits<char> > &,boost::lambda::lambda_functor<boost::lambda::placeholder<1> >,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,bo ost::tuples::null_type,boost::tuples::null_type,boost::tuples::nu..." uses "the identity conversion". "./boost/lambda/detail/operator_lambda_func_base.hpp", line 212.1: 1540-1231 (I) The conversion from argument number 2 to "int &" uses "the identity conversion". "./boost/lambda/detail/operator_lambda_func_base.hpp", line 212.1: 1540-1231 (I) The conversion from argument number 3 to "const boost::tuples::null_type &" uses "the identity conversion". "./boost/lambda/detail/operator_lambda_func_base.hpp", line 212.1: 1540-1231 (I) The conversion from argument number 4 to "const boost::tuples::null_type &" uses "the identity conversion". "./boost/lambda/detail/operator_lambda_func_base.hpp", line 212.1: 1540-1231 (I) The conversion from argument number 5 to "const boost::tuples::null_type &" uses "the identity conversion". "./boost/lambda/detail/select_functions.hpp", line 22.13: 1540-1202 (I) No candidate is better than "boost::lambda::detail::select<const boost::lambda::lambda_functor<boost::lambda::lambda_functor_base<boost::lambda: :bitwise_action<boost::lambda::leftshift_action>,boost::tuples::tuple<std::basi c_ostream<char,std::char_traits<char> > &,boost::lambda::lambda_functor<boost::lambda::placeholder<1> >,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,bo ost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,boost: :tuples:...". "./boost/lambda/detail/operator_lambda_func_base.hpp", line 212.1: 1540-1231 (I) The conversion from argument number 1 to "const boost::lambda::lambda_functor<boost::lambda::lambda_functor_base<boost::lambda: :bitwise_action<boost::lambda::leftshift_action>,boost::tuples::tuple<std::basi c_ostream<char,std::char_traits<char> > &,boost::lambda::lambda_functor<boost::lambda::placeholder<1> >,boost::tuples::null_type,boost::tuples::null_type,boost::tuples::null_type,bo ost::tuples::null_type,boost::tuples::null_type,boost::tuples::nu..." uses "the identity conversion". "./boost/lambda/detail/operator_lambda_func_base.hpp", line 212.1: 1540-1231 (I) The conversion from argument number 2 to "int &" uses "the identity conversion". "./boost/lambda/detail/operator_lambda_func_base.hpp", line 212.1: 1540-1231 (I) The conversion from argument number 3 to "const boost::tuples::null_type &" uses "the identity conversion". "./boost/lambda/detail/operator_lambda_func_base.hpp", line 212.1: 1540-1231 (I) The conversion from argument number 4 to "const boost::tuples::null_type &" uses "the identity conversion". "./boost/lambda/detail/operator_lambda_func_base.hpp", line 212.1: 1540-1231 (I) The conversion from argument number 5 to "const boost::tuples::null_type &" uses "the identity conversion". "./boost/lambda/detail/operator_lambda_func_base.hpp", line 212.1: 1540-0700 (I) The previous message was produced while processing "boost::lambda::lambda_functor_base<class boost::lambda::bitwise_action<boost::lambda::leftshift_action>,class boost::tuples::tuple<boost::lambda::lambda_functor<boost::lambda::lambda_functo r_base<boost::lambda::bitwise_action<boost::lambda::leftshift_action>,boost::tu ples::tuple<std::basic_ostream<char,std::char_traits<char> > &,boost::lambda::lambda_functor<boost::lambda::placeholder<1> >,boost::tuples::null_type,boost::tuples::null_t...". "./boost/lambda/detail/lambda_functors.hpp", line 145.3: 1540-0700 (I) The previous message was produced while processing "boost::lambda::lambda_functor<class boost::lambda::lambda_functor_base<boost::lambda::bitwise_action<boost::lambda: :leftshift_action>,boost::tuples::tuple<boost::lambda::lambda_functor<boost::la mbda::lambda_functor_base<boost::lambda::bitwise_action<boost::lambda::leftshif t_action>,boost::tuples::tuple<std::basic_ostream<char,std::char_traits<char> > &,boost::lambda::lambda_functor<boost::lambda::placeholder<1> >,boost::tuples::null_ty...". "/usr/vacpp/include/algorithm", line 77.13: 1540-0700 (I) The previous message was produced while processing "std::for_each<std::_Ptrit<int,long,int *,int &,int *,int &>,boost::lambda::lambda_functor<boost::lambda::lambda_functor_base<boost::lamb da::bitwise_action<boost::lambda::leftshift_action>,boost::tuples::tuple<boost: :lambda::lambda_functor<boost::lambda::lambda_functor_base<boost::lambda::bitwi se_action<boost::lambda::leftshift_action>,boost::tuples::tuple<std::basic_ostr eam<char,std::char_traits<char> > &,boost::lambda::lambda_functor<...". "test.cpp", line 13.3: 1540-0700 (I) The previous message was produced while processing "main()".

2 2

[asio] error code 11001
by Christian Henning 26 Sep '06

26 Sep '06

Hi there, I'm having problems to figure out what error code 11001 means. I have an boost::asio::error exception that is thrown inside tcp::resolver::resolve( query ) . So how can I translate this error code into something descriptive. Thanks ahead, Christian

1 1

[asio] demultiplexing non-socket file descriptors
by Bill Somerville 26 Sep '06

26 Sep '06

Hi Having a look at asio as a possible solution for a cleanup of an existing app. It would be nice to extend asio to include non-socket file descriptors. I realise that this would not be portable to Windows, but does asio provide extension points to add this functionality, also adding PF_LOCAL sockets would be handy as well although these could be switched to a PF_INET implementation with an acceptable performance penalty. Has anyone experimented with extensions like these? TIA -- Bill Somerville This message has been scanned by MailController - www.MailController.altohiway.com

1 0

[Boost Test] 1.35 - setting up VC 7 IDE to link with Boost.Test
by Robert Ramey 26 Sep '06

26 Sep '06

Using VC 7.1 I have a VC Solution with all my test programs. These use the serialization library and boost test - test_exec_monitor. I've recently wanted to make some changes in 1.35 and now none of my projects link anymore. They build with bjam but I can't get them linked with VC 7 IDE. I don't have autolink suppressed. There is no message indicating that it can't find file test.....lib. What I get is undefined symbols. This i od to me as I don't use any symbosl unit_test .... I've also tried including the library unit_test_framework. That doesn't seem to help either. Any suggestions would be appreciated. Robert Ramey test_simple_class.obj : error LNK2019: unresolved external symbol "void __cdecl boost::test_tools::tt_detail::check_impl(class boost::test_tools::predicate_result const &,class boost::basic_wrap_stringstream<char> &,class boost::unit_test::basic_cstring<char const >,unsigned int,enum boost::test_tools::tt_detail::tool_level,enum boost::test_tools::tt_detail::check_type,unsigned int,...)" (?check_impl@tt_detail@test_tools@boost@@YAXABVpredicate_result@23@AAV?$basic_wrap_stringstream@D@3@V?$basic_cstring@$$CBD@unit_test@3@IW4tool_level@123@W4check_type@123@IZZ) referenced in function "int __cdecl test_main(int,char * * const)" (?test_main@@YAHHQAPAD@Z) test_simple_class.obj : error LNK2019: unresolved external symbol "public: void __thiscall boost::unit_test::unit_test_log_t::set_checkpoint(class boost::unit_test::basic_cstring<char const >,unsigned int,class boost::unit_test::basic_cstring<char const >)" (?set_checkpoint@unit_test_log_t@unit_test@boost@@QAEXV?$basic_cstring@$$CBD@23@I0@Z) referenced in function "int __cdecl test_main(int,char * * const)" (?test_main@@YAHHQAPAD@Z) test_simple_class.obj : error LNK2001: unresolved external symbol "public: virtual void __thiscall boost::unit_test::unit_test_log_t::exception_caught(class boost::execution_exception const &)" (?exception_caught@unit_test_log_t@unit_test@boost@@UAEXABVexecution_exception@3@@Z) test_simple_class.obj : error LNK2001: unresolved external symbol "public: virtual void __thiscall boost::unit_test::unit_test_log_t::assertion_result(bool)" (?assertion_result@unit_test_log_t@unit_test@boost@@UAEX_N@Z) test_simple_class.obj : error LNK2001: unresolved external symbol "public: virtual void __thiscall boost::unit_test::unit_test_log_t::test_unit_aborted(class boost::unit_test::test_unit const &)" (?test_unit_aborted@unit_test_log_t@unit_test@boost@@UAEXABVtest_unit@23@@Z) test_simple_class.obj : error LNK2001: unresolved external symbol "public: virtual void __thiscall boost::unit_test::unit_test_log_t::test_unit_skipped(class boost::unit_test::test_unit const &)" (?test_unit_skipped@unit_test_log_t@unit_test@boost@@UAEXABVtest_unit@23@@Z) test_simple_class.obj : error LNK2001: unresolved external symbol "public: virtual void __thiscall boost::unit_test::unit_test_log_t::test_unit_finish(class boost::unit_test::test_unit const &,unsigned long)" (?test_unit_finish@unit_test_log_t@unit_test@boost@@UAEXABVtest_unit@23@K@Z) test_simple_class.obj : error LNK2001: unresolved external symbol "public: virtual void __thiscall boost::unit_test::unit_test_log_t::test_unit_start(class boost::unit_test::test_unit const &)" (?test_unit_start@unit_test_log_t@unit_test@boost@@UAEXABVtest_unit@23@@Z) test_simple_class.obj : error LNK2001: unresolved external symbol "public: virtual void __thiscall boost::unit_test::unit_test_log_t::test_aborted(void)" (?test_aborted@unit_test_log_t@unit_test@boost@@UAEXXZ) test_simple_class.obj : error LNK2001: unresolved external symbol "public: virtual void __thiscall boost::unit_test::unit_test_log_t::test_finish(void)" (?test_finish@unit_test_log_t@unit_test@boost@@UAEXXZ) test_simple_class.obj : error LNK2001: unresolved external symbol "public: virtual void __thiscall boost::unit_test::unit_test_log_t::test_start(unsigned long)" (?test_start@unit_test_log_t@unit_test@boost@@UAEXK@Z) MSVCRTD.lib(crtexe.obj) : error LNK2019: unresolved external symbol _main referenced in function _mainCRTStartup

3 3

autolink include guard ?
by Robert Ramey 26 Sep '06

26 Sep '06

I notice that when my tests build I get Linking to lib file: libboost_serialization-vc71-mt-gd-1_35.lib Linking to lib file: libboost_serialization-vc71-mt-gd-1_35.lib I was curious as to why I go two such messages. Looking at auto_link.hpp I see that there is no include guard no a #pragma once. Is there a reason for this? Robert Ramey

2 1

Re: [Boost-users] [iostreams] Implementing a block cipher as a filter
by Pfligersdorffer, Christian 26 Sep '06

26 Sep '06

Hello all! Seems I am the first one to reply to my own post :-) I am not so much surprised however, since this stuff is kinda weird and complicated. Nevertheless I got some news for you: after replacing the gzip- with bzip2-compression filters everything worked fine!! This means there is some (very subtle) bug or incompatibility in the gzip filters, which I of course did not expect (but rather was looking in my code of course). For the protocoll: gzip_decompressor raises a gzip_error exception with internal error_ = -3 when reaching the end of the stream. Unfortunately this behaviour could not be reproduced without actual encrypting/decrypting. Simply doing a null-transformation by replacing encrypt() and decrypt() with memcpy() does not yield the error. I did some tests: reading a file, writing it to a filtering_ostream using filter X into some file, again reading through filtering_istream using Y and comparing with the original file. X = block_crypter, Y = block_crypter ok, identity X = gzip_compressor, Y = gzip_decompressor ok, identity X = block_crypter|bzip2_compressor, Y = block_crypter|bzip2_decompressor ok, identity X = block_crypter|gzip_compressor, Y = block_crypter|gzip_decompressor error, see above and now get yourself a good seat: X = gzip_compressor|block_crypter, Y = gzip_decompressor|block_crypter ok, identity Of course compressing an encrypted file is not the same as encrypting the compressed file, which is much faster and results in smaller files. So I tried this just to see what happens the other way round. Throughout the test I used file_sink and file_source in binary-mode as devices. Have fun fixing this ;-) -- Christian Pfligersdorffer Dipl.-Ing. Bakk.rer.nat. Software Engineering EOS GmbH - Electro Optical Systems Robert-Stirling-Ring 1 D-82152 Krailling / Munich Phone +49 89 893 36-229 Fax +49 89 893 36-287 christian.pfligersdorffer(a)eos.info http://www.eos.info

1 0

[smart_ptr] comparison operators: shared_ptr == weak_ptr?
by Matt.Sullivan＠leica-geosystems.com 26 Sep '06

26 Sep '06

Hi, Probably a newbie question, but what's the best way to test if a shared_ptr and weak_ptr point to the same thing? My current code uses: if (shared_ptr != weak_ptr.lock()) but it feels wrong to create a temporary with some small locking overhead - even though I realise it will make absolutely no difference to performance. So, my question is really why is there no operator==(shared_ptr, weak_ptr)? Google provided little explanation other than this: http://std.dkuug.dk/jtc1/sc22/wg21/docs/papers/2004/n1590.html which approaches the subject but isn't exactly authoritative. thanks, Matt

3 4

boost serialization
by Anna Kloper 25 Sep '06

25 Sep '06

Hi all, I'm new to BOOST and need help with this kind of problem of pointers serialization: class A{ public: A(int *anInt):m_pi(anInt){} ~A(){} private: int *m_pi; }; class B{ public: B(int *anInt):m_a1(anInt),m_a2(anInt){} ~B(){} private: A m_a1; A m_a2; }; int main() { int i=1; B b(&i); //serialize b i=2; //serialize b //de-serialize b expected i = 1 and b.m_a1=b.m_a2=1 //de-serialize b expected i = 2 and b.m_a1=b.m_a2=2 } Now, assuming that there are serialization functions for class A and B I'd like to serialize object b swice with track never so that when de-serializing b I'd like b to contain a pointer to the location of i. The problem is that when I de-serializing b I notice that b doesn't pointer to the location of i anymore but to another location. I need this for serializing of communication, so I need to save all the data trough a pointer and read the data back step by step for preprocessing to the same location in the memory. Is there anything I can do to overcome this problem with pointers? Thank you in advance, Anna. --------------------------------- Do you Yahoo!? Everyone is raving about the all-new Yahoo! Mail.

2 1

newbie [boost::test] linking in MSVC6
by Brian Hall 25 Sep '06

25 Sep '06

I have been using boost and STLPort for sometime and I have built up unit tests for my projects that have worked fine up until now. However, I've been lazy and used the #include unit_test_framework.hpp route instead linking to libraries. Now I'm stuck. My tests won't compile with STLPort 5.0.x, apparently because the complier needs more memory (I'm using MS VC++6(SP5) and I've set the complier option /Zm to extend to its maximum). So I decided to build the boost libraries (boost 1_33_1). Unfortunately, now I can't get my testing code to link with these libraries! Could anyone tell me which of the following I should be linking to (I am building in 'release' mode with multithreading)? libboost_unit_test_framework-vc6-mt-gdp-1_33_1.lib libboost_unit_test_framework-vc6-mt-gdp.lib libboost_unit_test_framework-vc6-mt-p-1_33_1.lib libboost_unit_test_framework-vc6-mt-p.lib libboost_unit_test_framework-vc6-mt-sgdp-1_33_1.lib libboost_unit_test_framework-vc6-mt-sgdp.lib libboost_unit_test_framework-vc6-mt-sp-1_33_1.lib libboost_unit_test_framework-vc6-mt-sp.lib In fact, I've tried them all without success. Here is an example error message: libboost_unit_test_framework-vc6-mt-sp-1_33_1.lib(framework.obj) : error LNK2001: unresolved external symbol "class boost::unit_test::test_suite * __cdecl init_unit_test_suite(int,char * * const)" (?init_unit_test_suite@@YAPAVtest_suite@unit_test@boost@@HQAPAD@Z) Release/mst_gum_tree_real_dev.exe : fatal error LNK1120: 1 unresolved externals Error executing link.exe. Also, I simply removed the #include of unit_test_framework.hpp in my original source code. Is that correct? The remaining includes are: unit_test.hpp and floating_point_comparison.hpp. As an alternative to linking to the libraries, I have tried to include the source files in my project, as suggested in the unit test documentation, but that doesn't work either! The documentation does not appear to be up to date. What is a poor boy to do?!! Please give me some ideas

3 3

reference in new- and old-style iterators
by Jens Theisen 25 Sep '06

25 Sep '06

Hello, I'm wondering what the reference member in the iterator_traits of an iterator is required to be. I couldn't find any requirement at all in the C++98 standard, and more surprisingly, I can't see any requirement in the new iterator proposal either. In particular, operator* does not seem to be required to return the iterator_traits< Iterator >::reference for lvalue iterators. At one point, however, the proposal suggests that this was the intention: "...would have a return type of reference; the same as operator*." where reference has a font style indicating that it's the iterator_traits's notion of reference. I'm looking at the proposal version currently published along in the documentation of the boost iterator library. So my questions: - Am I right in my suspicion that in the STL, the reference iterator_trait is entirely useless if taken strictly? - Should the proposal not better require the reference to match with operator*'s return type for lvalue iterators? If not, what's its use? - Is this off-topic here? :) Regards, Jens

2 1

bug in boost::random?
by boost＠larroy.com 24 Sep '06

24 Sep '06

Hi, First of all boost::random is very clever and complete, thanks! Using boost::random I found uniform_int distribution not working in my box. I have version 1.33 on a Debian system. This is an example of a program that triggers a non-uniform integer distribution. I'm I doing something wrong? Regards. #include <iostream> #include <string> #include <cstdlib> #include <cassert> #include<vector> #include<stdexcept> #include <boost/random.hpp> #include <limits> using namespace std; int main(int argc, char *argv[]) { boost::mt19937 rng; boost::uniform_int<int64_t> ui(numeric_limits<int64_t>::min(),numeric_limits<int64_t>::max()); boost::variate_generator<boost::mt19937&, boost::uniform_int<int64_t> > rgen(rng, ui); while(true) { cout << rgen() << endl; } } -- Pedro Larroy Tovar, pedro at larroy dot com | http://pedro.larroy.com/ * Las patentes de programación son nocivas para la innovación * http://proinnova.hispalinux.es/

1 0

VS2003 Linking issuse
by Anthony Mason 22 Sep '06

22 Sep '06

Hi guys, I know this is probably a common problem, but I haven't found any help on any google searches so far... I've got my app compiling in debug mode fine using the boost_date_time and boost_filesystem libraries, compiling using Multithreaded Debug, but when I set up my Release mode compile using just plain Multithreaded I get a ton of LNK2005 messages similar to : error LNK2005: "public: static unsigned int const std::ctype<char>::table_size"(?table_size@$ctype@D@std@@2IB)already defined in libboost_date)time-vc71-mt-s-1_33_1.lib(greg_month.obj) I get about 70 of these errors between date_time and filesystem libraries. I'm linking against the same libraries (mt-s) both debug and release mode. I was hoping that someone could give me some advice. Thanks, Anthony

1 0

[iostreams] Implementing a block cipher as a filter
by Pfligersdorffer, Christian 22 Sep '06

22 Sep '06

Dear community, I'm on my way to learn writing filters for the iostreams library and find it very hard. I want to compress and encrypt data, so I use the gzip-filters (that are already provided) and some self-tailored crypto-filter. Using a symmetric block cipher should be just fine with the framework, since data from a stream is usually fed in portions to the filter (128 Bytes by default). Of course not when you use an aggregate_filter, which was my first attempt because it is so simple. Implementing a multichar_dual_use_filter seemed simple too but I am experiencing weird behaviour. Such as having runtime errors when reading an encrypted compressed file but not when reading compressed encrypted files. Also I am not entirely sure that I understood the documentation... Here is what I do, perhaps you gurus instantly see what I'm doing wrong: _________________________________________________________________________ class block_crypter : public boost::iostreams::multichar_dual_use_filter { const std::string pw; char* buffer; int length; void reallocate_buffer(std::size_t n) { if (length < n) { if (buffer) free(buffer); buffer = (char*) malloc(n); length = n; } } public: block_crypter(const char* password) : pw(password), buffer(NULL), length(0) {} ~block_crypter() { if (buffer) free(buffer); } template<typename Source> std::streamsize read(Source& src, char* s, std::streamsize n) { // Read up to n filtered characters into the buffer s, // returning the number of characters read or -1 for EOF. // Use src to access the unfiltered character sequence reallocate_buffer(n); std::streamsize count = boost::iostreams::read(src, buffer, n); assert(count <= n); if (count <= 0) return -1; decrypt(pw, buffer, count, s); return count; } template<typename Sink> std::streamsize write(Sink& dest, const char* s, std::streamsize n) { // Consume up to n filtered characters from the buffer s, // writing filtered characters to dest. Return the number // of characters consumed. reallocate_buffer(n); encrypt(pw, s, n, buffer); std::streamsize count = boost::iostreams::write(dest, buffer, n); assert(count <= n); return count; } }; BOOST_IOSTREAMS_PIPABLE(block_crypter, 0) _________________________________________________________________________ The encrypt() and decrypt() functions produce a character sequence of the exact same length as the input sequence. All char values can occur which might be a problem but I don't know. Runtime errors always occur at the end of the stream, i.e. on the last run of the filter. Perhaps I did not understand the EOF mechanics or am mixing up something. But then, it compiles and seems to behave properly if used alone. Only in read-mode preceding gzip-deflation there is an error. I hope someone can help me there. BTW: I did not even try to implement my filter as symmetric_filter. I cannot see how anyone would be able to do this given the present documentation or existing "examples". Another thing that clearly arises is the block size issue n which has to be the same for writing and reading in order to produce the correct plain text again. Maybe the optimally_buffered_tag should be used instead of trusting in always the same default filter buffer size? Thanks for your suggestions, -- Christian Pfligersdorffer Dipl.-Ing. Bakk.rer.nat. Software Engineering EOS GmbH - Electro Optical Systems Robert-Stirling-Ring 1 D-82152 Krailling / Munich Phone +49 89 893 36-229 Fax +49 89 893 36-287 christian.pfligersdorffer(a)eos.info http://www.eos.info

1 0

boost::interprocess::managed_external_buffer class restrictions
by alexmark 22 Sep '06

22 Sep '06

The problem is the class managed_external_buffer currently does not provide public default c-tor and interface functions create(), open(), close(). I'm writing DLL, where I need a global object of type managed_external_buffer. This object is "connected" to mapped view of paging file within processing of DLL_PROCESS_ATTACH and disconnected at DLL_PROCESS_DETACH like that: HANDLE g_hfm; LPVOID g_buf_base_addr; managed_external_buffer g_buf; BOOL APIENTRY DllMain(,,,. ULONG reason, ...) { switch (reason) { case DLL_PROCESS_ATTACH: if (!Attach()) return FALSE; break; case DLL_PROCESS_DETACH: Detach(); break; } return TRUE; } bool Attach () { ... g_hfm = CreateFileMapping(0xFFFFFFFF, ...); // use paging file g_buf_base_addr = MapViewOfFile(g_hfm, ...); g_buf.create(g_buf_base_addr, ...); ... MyObj* p = g_buf.construct(...); ... } void Detach () { ... g_buf.destroy_ptr(p); ... g_buf.close(); UnmapViewOfFile(g_buf_base_addr); CloseHandle(g_hfm); ... } As a workaround, I wrote my own class "managed_user_buffer" derived from boost::interprocess::detail::basic_managed_memory_impl and providing public default c-tor and create()/open()/close() methods. I just made a copy of managed_external_buffer.hpp and slightly modified the code. But it's not so clear, why managed_external_buffer class itself exposes the restricted interface? I suppose the class would be more usable w/o the restrictions like that. Or not? Moreover, in boost::shmem::named_shared_object class this functionality was available. Thanks, Alex.

2 1

BGL and maximum spanning trees
by aitor 22 Sep '06

22 Sep '06

Hello, in my project i need to compute the maximum spanning tree of an undirected weighted graph. One possible solution is to could iteratively convert each weight wij to 1/wij and apply prim_minimum_spanning_tree algorithm over it. However, i wonder if i could slightly change the prim_minimum_spanning_tree algorithm to a prim_maximum_spanning_tree function by changing only the compare predicate (in line 39 of prim_minimum_spanning_tree.hpp) from std::less<W> compare; to std::greater<W> compare; Wold then the function compute a maximum spanning tree ? Or am i missing something important ?

2 1

boost+stlport+Xcode
by Don Agro 22 Sep '06

22 Sep '06

Has anyone had any luck linking boost into an XCode application that is also using STLport ? I am using STLport 5.0.0 and boost 1.33.1 Boost links in fine unless I also link in STLport then I have one undefined symbol... boost::signals::detail::signal_base::signal_base (boost::function2<bool, boost::signals::detail::stored_group, boost::signals::detail::stored_group, stlp_std::allocator<boost::function_base> > const&, boost::any const&) bjam build (with STLport at "/STLport-5.0.0" bjam -sSTLPORT_PATH="/" -sSTLPORT_VERSION="5.0.0" -sTOOLS="darwin" Any ideas ? Thanks in advance.

2 2

[boost::filesystem] path namecheck : want to use "native" on Windows ?
by Washburn 22 Sep '06

22 Sep '06

I'm using Boost on Windows and the filesystem::path behaviour seems incorrect with the default name check, so I want to use the "native" namecheck instead. First of all, is this normal ? (since Boost is compiled for windows platformn should'nt the right name check be set by default ?) I initialize it manually using : filesystem::path::default_name_check( filesystem::native ) But since it can only be done once, this throws exceptions occasionnaly (not very important, but "ugly") Is there a better way to set the name check at the start of the application ? Washburn

3 2

boost/pool/detail/mutex.hpp and threads on HP-UX
by mojmir.svoboda＠logicacmg.com 22 Sep '06

22 Sep '06

hello, i'm trying to build opendiameter (uses boost) with gcc 3.4.3 on a hp box: HP-UX bruno B.11.23 U 9000/800 1532750548 unlimited-user license and i've encountered following error when compiling libdiamparser: boost_1_33_1/boost/pool/detail/mutex.hpp:41:4: #error Unable to determine platform mutex type; define BOOST_NO_MT to assume single-threaded well, according to <sys/unistd.h> _POSIX_THREADS is still undefined on HP-UX: /************************************************************************ * The following defines are specified in the standard, but are not yet * implemented: * _POSIX_THREADS can't be defined until all features are implemented ... i've found similar problem in python and the solution uses check for _SC_THREADS instead of _POSIX_THREADS. yet better solution may use BOOST_HAS_PTHREADS: boost_1_33_1/boost/pool/detail $ diff -Naur mutex.hpp.orig mutex.hpp --- mutex.hpp.orig 2006-09-19 14:20:53.000000000 +0200 +++ mutex.hpp 2006-09-19 16:11:50.000000000 +0200 @@ -31,7 +31,7 @@ #define BOOST_MUTEX_HELPER BOOST_MUTEX_HELPER_WIN32 #else #include <unistd.h> - #ifdef _POSIX_THREADS + #ifdef BOOST_HAS_PTHREADS #define BOOST_MUTEX_HELPER BOOST_MUTEX_HELPER_PTHREAD #endif #endif @@ -45,7 +45,7 @@ # ifdef BOOST_WINDOWS # include <windows.h> # endif -# ifdef _POSIX_THREADS +# ifdef BOOST_HAS_PTHREADS # include <pthread.h> # endif #endif @@ -83,7 +83,7 @@ #endif // defined(BOOST_WINDOWS) -#ifdef _POSIX_THREADS +#ifdef BOOST_HAS_PTHREADS class pthread_mutex { @@ -107,7 +107,7 @@ { pthread_mutex_unlock(&mtx); } }; -#endif // defined(_POSIX_THREADS) +#endif // defined(BOOST_HAS_PTHREADS) #endif // !defined(BOOST_NO_MT) because the file <boost/config/platform/hpux.hpp> defines BOOST_HAS_PTHREADS for us on the hpux+gcc. is it allright? thanks fya, mojmir This e-mail and any attachment is for authorised use by the intended recipient(s) only. It may contain proprietary material, confidential information and/or be subject to legal privilege. It should not be copied, disclosed to, retained or used by, any other party. If you are not an intended recipient then please promptly delete this e-mail and any attachment and all copies and inform the sender. Thank you.

2 1

boost::interprocess::managed_external_buffer - link errors
by alexmark 22 Sep '06

22 Sep '06

When I include boost/interprocess/managed_external_buffer.hpp in more than one file within a solution (MSVC 7.1) I get linker errors LNK2005 and LNK4006 because of boost::interprocess::fill_system_message(...) function redefinition. The same is applicable to the case when this header file is included in stdafx.h only. fill_system_message(...) is a standalone function, not a member of a class. And the body of it is included in header file. May it be the point the problem originates from? Maybe the better way is to move "fill_system_message(...)" to .cpp source file? Have anybody faced this problem? Thanks, Alex.

2 1

How to do code factoring when using Boost.Program_options?
by Peng Yu 21 Sep '06

21 Sep '06

Hi, Suppose that I have program option set U. I have many programs which uses a subset of U as their options. Some of them share the same subset. For now, I code all the options in the main function like the one in the tutorial http://www.boost.org/doc/html/program_options/tutorial.html However, there is a problem when I have a lot programs with similar options. I would like to factor out the common code. But I don't have an idea how to do it in a good way. If you happen to have some experience, please let me know and share your experience with me. Thanks, Peng

2 2

[boost::signal][boost::bind] signal::disconnect problem with MSVC 2005
by david callu 21 Sep '06

21 Sep '06

Hi, See this code ... #include<iostream> #include<boost/bind.hpp> #include<boost/signal.hpp> struct CSignal { typedef boost::signal< void (void) > UpdateSignal; UpdateSignal sig; }; struct CSlot {: void update(int i) { std::cout << "Call void update( " << i << " )" << std::endl; } void connect(CSignal& cs) { cs.sig.connect(boost::bind(&CSlot::update, this, 5)); } void disconnect(CSignal& cs) { cs.sig.disconnect(boost::bind(&CSlot::update, this, 5)); } }; int main() { CSignal csignal; CSlot cslot; cslot.connect(csignal); csignal.sig(); cslot.disconnect(csignal); csignal.sig(); return (0); } When i compile with GCC 4.1.1, this compile fine. But when i compile with MSVC 2005 it report an error: .\main.cpp(30) : error C2664: 'boost::signal1<R,T1,Combiner,Group,GroupCompare,SlotFunction>::disconnect' : cannot convert parameter 1 from 'boost::_bi::bind_t<R,F,L>' to 'const int &' with [ R=void, T1=int, Combiner=boost::last_value<void>, Group=int, GroupCompare=std::less<int>, SlotFunction=boost::function<void (int)> ] and [ R=void, F=boost::_mfi::mf1<void,CSlot,int>, L=boost::_bi::list2<boost::_bi::value<CSlot *>,boost::arg<1>> ] Reason: cannot convert from 'boost::_bi::bind_t<R,F,L>' to 'const int' with [ R=void, F=boost::_mfi::mf1<void,CSlot,int>, L=boost::_bi::list2<boost::_bi::value<CSlot *>,boost::arg<1>> ] No user-defined-conversion operator available that can perform this conversion, or the operator cannot be called have you any idee to solve this problem? thank david callu

3 4

Boost.signals with -pthread
by Pavel Syomin 21 Sep '06

21 Sep '06

Hi, all! I am novice in this list, so don't beat freely :) I confronted with a strange thing using boost.signals on SLES 9 SP3. I don't shure Boost.signals bug, becase on FC4 and RHEL AS 3 all fine. Test case: --------------------- CUT HERE ------------------ #include <boost/signal.hpp> #include <iostream> struct MySlot { void operator() () { std::cout << "YES!" << std::endl; } }; MySlot myslot; boost::signal<void ()> mysig; int main() { mysig.connect(myslot); return 0; } --------------------- CUT HERE ------------------ Compile and run: c++ test.cc -o test -lboost_signals ./test Programm will succesfully exit. Compile and run: c++ test.cc -o test -lboost_signals -pthread ./test Programm will not exit never. Boost version: 1.31.0 (from SuSE rpm) GCC version: c++ (GCC) 3.3.3 (SuSE Linux) I run this test on other SuSE boxes with same results. Any ideas? P.S. I can't use GCC without '-pthread' because my program use threads...

2 5

[Boost Conference] Save the Date
by David Abrahams 21 Sep '06

21 Sep '06

================================ Save the Date: May 14-18, 2007 ================================ We're pleased to issue this pre-announcement of the first annual Boost Conference, BoostCon 2007. The conference will take place in Aspen, Colorado, May 14-18. This promises to be the main face-to-face event for all things Boost, from from using Boost libraries to writing them, from evangelizing Boost to deployment within your organization, from infrastructure and process to vision and mission, and from TR1 to TR2. Given the range and interests of the participants, this event promises to be intense and in-depth. Due to the breadth of our community, the conference will be organized into two primary tracks: one directed mostly at hard-core Boost developers, and the other focused on the practical interests of Boost end-users. In the spirit of Boost, however, the conference will be planned to foster collaboration and interaction both within *and* across these tracks, with an emphasis on hands-on, participatory sessions. More details, including a call for session proposals, will be forthcoming in the next few weeks. Enrollment for this event will be limited, so we're issuing this notice to the Boost community well in advance. In the meantime, we have set up a page on the Boost Wiki where we're doing an informal, preliminary survey of interest (http://www.crystalclearsoftware.com/cgi-bin/boost_wiki/wiki.pl?BoostCon) If you want to be a part of the inaugural BoostCon and are likely to attend, we'd appreciate it if you'd add yourself (or an alias) to the list there, to help us with event planning. Thanks, The BoostCon 2007 Organizers ------------------------------------------------------------------ David Abrahams Beman Dawes Jeff Garland Kevlin Henney Scott Meyers Eric Niebler Sean Parent Rene Rivera Jeremy Siek Matthias Troyer ------------------------------------------------------------------

2 2

Boost/ptr_vector and BCB6
by Ivo Trowitzsch 21 Sep '06

21 Sep '06

Hello everyone, I am new to Boost. I am using Borland C++ Builder 6 (bcc32 v5.6). Now I wanted to use the ptr_container/ptr_vector: So I included <boost/ptr_container/ptr_vector.hpp>. that's where the trouble starts, without actually using a ptr_vector. Compiling leaves me with errors in reversible_ptr_container.hpp: "reversible_ptr_container.hpp(487): E2404 Dependant type qualifier 'reversible_ptr_container<Config,CloneAllocator>' has no member type named 'allow_null'." To be honest: I have no clue, what to do to to get rid of that error. I guess ptr_vector should work on the bcc32, at least I was not able to find anything related to this error searching this mailing-list's archive and elsewhere with google. I imagine I might have set some compiler's settings wrong or something, but I don't know. If anyone could help me out on this, I'd be very thankful! Ivo.

2 1

Probably bug in condition::timed_wait()
by Pavel Syomin 21 Sep '06

21 Sep '06

Hi, I'm porting custom library from UNIX to Windows and found that some piece of code work correctly on UNIX and some time segfaulting on Windows. I think, that problem is on boost::condition::timed_wait() function. To be sure I write small test: #include <stdexcept> #include <iostream> #include <boost/thread.hpp> #include <windows.h> using namespace boost; using namespace std; class AsyncQueue { public: AsyncQueue() : m_counter(0) {} void push() { mutex::scoped_lock lock(m_mutex); m_counter++; m_condition.notify_one(); } void timed_pop(const xtime &time) { mutex::scoped_lock lock(m_mutex); if(m_counter) { m_counter--; return; } if(!m_condition.timed_wait(lock, time)) return; if(!m_counter) throw out_of_range("oops..."); m_counter--; } private: mutex m_mutex; condition m_condition; int m_counter; }; static AsyncQueue queue; static void start() { for(;;) { queue.push(); Sleep(100); } } int main(int argc, char **argv) { thread thread(start); xtime time; for(;;) { xtime_get(&time, TIME_UTC); time.nsec += 10000; queue.timed_pop(time); } return 0; } AsyncQueue is a simple asynchronous queue container with two operations - push() and timed_pop(). Because this is test, AsyncQueue don't really collect something, but it's has variable (m_counter field) that count current number on elements in container. When push() called m_counter incremented and when timed_pop() "virtually" remove item from queue m_counter decremented. In main() I create additional thread, which push data to queue. Data popped from queue in main thread by calling timed_pop(). But sometimes timed_pop throw out_of_range exception. If you look in code you can see that it's mean that condition::timed_wait() return true, but queue is empty! I look to boost-users list and found e-mail's about similar problems from Eric Colleu, but decision wasn't found. Two words about my environment. I use Visual Studio 2005, Windows XP SP2 on VMWare 5.5.1. Boost version is 1.33.1. Thanks for constructive answers.

3 5

[asio]how can I wait the last handler return in destructor
by Wang Yun 21 Sep '06

21 Sep '06

Hi all, I have a class class Connection { ... ~Connection() { _socket.close(); } void receiveHandler() { // will crash } tcp::socket _socket; } io_service.run() is called in a working thread, and there are many other sockets runing on the io_service. I call async_read on the _socket, and bind Connection::receiveHandler() as the handler function. Then I delete the Connection object in main thread, the receive operation will be cancelled and the receiveHandler() will be called with errcode boost::asio::error::operation_aborted, but at that time, the Connection object has been deleted, calling receiveHandler() will crash if it access the object's data member. Because there are still other sockets running on the io_service, I can't just join the working thread in Connection's destructor. I want to ensure the socket is closed completely and no more handler will be called in the destructor. One method is create an event before calling _socket.close(), then wait for the event, in receiveHandler(), set the event. Are there any easier method to do this? Thanks, Wang Yun

2 2

program_options ??
by Konstantin 20 Sep '06

20 Sep '06

Hi! Try to umderstand boost and... have got a trable. What are wrong? // no boost: void CommandLineParser::Parse(void) { wostringstream wostr; m_szArglist = CommandLineToArgvW(GetCommandLineW(), &m_nArgs); if( NULL == m_szArglist ) { wostr << L"CommandLineToArgvW failed" << ends; m_objErrFileWriter->PutLineIntoLogFile(wostr.str()); return ; } else wostr << endl ; for( int i=0; i < m_nArgs; ++i) { wostr << L"Command line parameter " << i << " is " << m_szArglist[i] << endl ; } wostr << ends ; m_objLogFileWriter->PutLineIntoLogFile( wostr.str()); // OK. //in file //Command line parameter 0 is C:\UPL\projects\vc\game\ufo_pl.exe //Command line parameter 1 is --help } // with boost: BOOL CommandLineParser::Parse(BOOL boost) { //vector<string> args = po::split_winmain(GetCommandLineW()); // not for wstring //vector<string> args = po::split_winmain(lpCmdLine); // not get file name and path vector<wstring> args = po::split_winmain(GetCommandLineW()); try { // po::options_description desc(L"Allowed options"); // not work whith wstring po::options_description desc("Allowed options"); desc.add_options() // (L"help", L"produce help message") // not work ("help", "produce help message"); po::variables_map vm; po::store(po::wcommand_line_parser(args).options(desc).run(), vm); po::notify(vm); if (vm.count("help")) // do not catch a "help" ???????????? { // not work //wostringstream wosstr; //wosstr << desc << endl; //MessageBoxW(NULL, wosstr.str().c_str(), L"Allowed options", MB_OK); ostringstream ostrem; ostrem << desc << endl; MessageBoxA(NULL, ostrem.str().c_str(), "Allowed options", MB_OK); return FALSE; } } catch(exception& e) { wcerr << "error: " << e.what() << "\n"; return TRUE; } catch(...) { wcerr << "Exception of unknown type!\n"; } return TRUE; }

1 0

Re: [Boost-users] Boost serialization : concurrency
by Robert Ramey 20 Sep '06

20 Sep '06

Daniel F. Savarese wrote: > In message > <1DDB0D3CC4E7F14FAE946361C0A606550143CA11(a)isr-jlm-mail.Kayote.com>, > "Moshe Matitya" writes: I want to thank you guys for spending time on this. I know it's time consuming and you have other things to do. I'm watching the discussion in the hope that a consensus will be achieved and I can just update i/oserializer with the conclusion. If you made a simple - reliable test case, I would consider adding it to the test suite as this aspect of the library is important to me. However, I realize that that might not be possible. And compromises - like presuming that no de-serialization occurs before main is called are very acceptable to me - given the alternatives. Note that the order of creation is related to the fact that we use this idiom - instantiation via the usage of static variables - in several places. On is to instantiate serializers for derived classes (later) and one for maintaining the global table of types that the system knows about (sooner) Maybe that is helpful. Robert Ramey

2 3

date_time question
by Arkadiy Vertleyb 20 Sep '06

20 Sep '06

Hi, I am looking at the possibility of replacing our custom-made datetime classes with the ones from boost::date_time. The library looks very attractive to me, and I would certainly go ahead and use it... however there is (at least) one catch, and this is the snap-to-end-of-month behavior of the months duration, according to which: {2000-Feb-29} + {1 month} = {2000-Mar-31} The problem is that it contradicts to the XSD spec we are using, http://www.w3.org/TR/2001/REC-xmlschema-2-20010502/#adding-durations-to-dat…, that says that months must be just "pinned to be within range". Maybe there is (could be added) some sort of policy, that could be used to achieve this behavior? Thanks, Arkadiy

2 2

Library Interface Design
by Scott Meyers 20 Sep '06

20 Sep '06

I have a question about library interface design in general with a strong interest in its application to C++, so I hope the moderators will view this at on-topic for a list devoted to the users' view of a set of widely used C++ libraries. In its most naked form, the question is this: how important is it that class constructors ensure that their objects are in a "truly" initialized state? I've always been a big fan of the "don't let users create objects they can't really use" philosophy. So, in general, I don't like the idea of "empty" objects or two-phase construction. It's too easy for people to make mistakes. So, for example, if I were to design an interface for an event log that required a user-specified ostream on which to log events, I'd declare the constructor taking an ostream parameter (possibly with a default, but that's a separate question, so don't worry about it): EventLog::EventLog(std::ostream& logstream); // an ostream must be // specified I've slept soundly with this philosophy for many years, but lately I've noticed that this idea runs headlong into one of the ideas of testability: that classes should be easy to test in isolation. The above constructor requires that an ostream be set up before an EventLog can be tested, and this might (1) be a pain and (2) be irrelevant for whatever test I want to perform. In such cases, offering a default constructor in addition to the above would make the class potentially easier to test. (In the general case, there might be many parameters, and they might themselves be hard to instantiate for a test due to required parameters that their constructors require....) Another thing I've noticed is that some users prefer a more exploratory style of development: they want to get something to compile ASAP and then play around with it. In particular, they don't want to be bothered with having to look up a bunch of constructor parameters in some documentation and then find ways to instantiate the parameters, they just want to create the objects they want and then play around with them. My gut instinct is not to have much sympathy for this argument, but then I read in "Framework Design Guidelines" that it's typically better to let people create "uninitialized" objects and throw exceptions if the objects are then used. In fact, I took the EventLog example from page 27 of that book, where they make clear that this code will compile and then throw at runtime (I've translated from C# to C++, because the fact that the example is in C# is not relevant): EvengLog log; log.WriteEntry("Hello World"); // throws: no log stream was set This book is by the designers of the .NET library, so regardless of your feelings about .NET, you have to admit that they have through about this kind of stuff a lot and also have a lot of experience with library users. But then on the third hand I get mail like this: > The .NET libraries have many objects with many constructors that leave the constructed object in a not ready-to-use state. > > An example: > System.Data.SqlClient.SqlParameter is a class that describes a bound parameter used in a database statement. Bound parameters are essential to prevent SQL injection attacks. They should be exceedingly easy to use since the "competition" (string concatenation of parameters into the SQL statement) is easy, well understood, and dangerous. > > However, the SqlParameter class has six constructors. Only two constructors create a sqlParameter object that can be immediately used. The others all require that you set additional properties (of course, which additional properties is unclear). Failure to prepare the SqlParameter object correctly typically generates an un-helpful database error when the SQL statement is executed. To add to the confusion, the first ctor shown by intellisense has 10 parameters (which, if set correctly, will instantiate a usable object). The last ctor shown by intellisense has only 2 parameters and is the most intuitive choice. The four in between are all half-baked. It's confusing, and even though I use it all the time, I still have to look at code snippets to remember how. So I'm confused. Constructors that "really" initialize objects detect some kind of errors during compilation, but they make testing harder, are arguably contrary to exploratory programming, and seem to contradict the advice of the designers of the .NET API. Constructors that "sort of" initialize objects are more test-friendly (also more loosely coupled, BTW) and facilitate an exploratory programming style, but defer some kinds of error detection to runtime (as well as incur the runtime time/space costs of such detection and ensuing actions). So, library users, what do you prefer, and why? Thanks, Scott

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Re: [Boost-users] converting value before inserting into a list
by Flex Ferrum 20 Sep '06

20 Sep '06

Hello. David Walthall wrote: > Flex Ferrum wrote: > > map<int,int> m; > > vector<int> a,b; > > std::transform(a.begin(), a.end(), std::back_inserter(b), var(m)[_1]); > Is this a case where transform is not appropriate? My understanding is > that the operation supplied to transform must not have any side effects, > and here m may be modified by operator[]. Does this count as a side effect? Yes, of course, map::operator[] _can_ have side effects. But if author of such code absolutely sure what each value from source vector has corresponded map entry then map::operator[] will not have side effects and will suitable for transormation operation. ____________ Best Regards Flex

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Boost.Python, MinGW, & ImportError
by Corey Wright 20 Sep '06

20 Sep '06

this is in reference to the following postings to c++-sig and boost-users: 1. http://lists.boost.org/boost-users/2006/02/17367.php 2. http://mail.python.org/pipermail/c++-sig/2006-September/011202.html the summary: individuals, including myself, are seeing "ImportError: dynamic module does not define init function (inithello)" whenever trying to import a module compiled with mingw against boost.python, specifically the python examples and tutorial distributed with boost. the symptom: g++ fails to properly link whenever a null library search path (ie -L"") is specified (because maybe it stops parsing arguments there?). the cause: MINGW_BIN_DIRECTORY is null the short answer (for those newbies just trying to get through the tutorial/example and don't care to dive into the details of boost.build): bjam -sMINGW_BIN_DIRECTORY=C:\MinGW\bin (or where ever your mingw installation is) the longer answer: see attached patch the explanation: A. in gcc-tools.jam: 1. the gcc-Link-action contains -L"$(STDLIBPATH:T)" 2. STDLIBPATH is set based on following commands: a. flags gcc GCC_STDLIB_DIRECTORY : $(GCC_STDLIB_DIRECTORY) ; b. GCC_STDLIB_DIRECTORY ?= $(GCC_ROOT_DIRECTORY)$(SLASH)lib ; c. flags gcc STDLIBPATH : $(GCC_STDLIB_DIRECTORY) ; but when using mingw, the values in gcc-tools.jam are set... B. in mingw-tools.jam 1. local GCC_BIN_DIRECTORY = $(MINGW_BIN_DIRECTORY) ; 2. local GCC_STDLIB_DIRECTORY = $(MINGW_STDLIB_DIRECTORY) ; 3. flags mingw STDLIBPATH : $(GCC_BIN_DIRECTORY) ; so for mingw, STDLIBPATH is always composed of GCC_BIN_DIRECTORY (which is really MINGW_BIN_DIRECTORY). if you set MINGW_STDLIB_DIRECTORY, but not MINGW_BIN_DIRECTORY, you end up with -L"mingw_stdlib_directory" -L"". you must set MINGW_BIN_DIRECTORY to get rid of the null string or insure the null string in MINGW_BIN_DIRECTORY never gets added to STDLIBPATH. i successfully compiled boost.python without needing to set MINGW_BIN_DIRECTORY because the mingw tools are in my path and everything "just works". but if you try to compile python extensions (or at least the tutorial and examples), then things start mysteriously failing. i haven't had time to fully test my patch by building all of boost with it applied, but i'm currently in the process and last i looked bjam had compiled date and filesystem libraries, and was working on iostreams. thanks for boost.python and the mingw support (it feels liberating to compile free software, gratis & libre, with free software; and we'll overlook the operating system ;-). -- undefined(a)pobox.com

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boost shmem
by Clarke, Trevor 20 Sep '06

20 Sep '06

I need to use shared memory in an application on Windows and Solaris so I've grabbed boost::shmem 0.93. It works fine on Windows but fails to compile on Solaris 10/SunPro 11. Has anybody had success on Solaris? I get the following errors when I try to compile. "boost/shmem/detail/segment_manager.hpp", line 253: Error: Redefining boost::shmem::detail::segment_manager<boost::shmem::detail::CharType, boost::shmem::detail::MemoryAlgorithm, boost::shmem::detail::IndexType<boost::shmem::detail::IndexConfig>> after use in boost::shmem::detail::segment_manager<char, boost::shmem::simple_seq_fit<boost::shmem::shared_mutex_family, boost::shmem::offset_ptr<void, boost::shmem::offset_1_null_ptr>>, boost::shmem::flat_map_index<boost::shmem::IndexConfig>>::index_config<c har>. "boost/shmem/indexes/flat_map_index.hpp", line 29: Where: While specializing "boost::shmem::detail::segment_manager<char, boost::shmem::simple_seq_fit<boost::shmem::shared_mutex_family, boost::shmem::offset_ptr<void, boost::shmem::offset_1_null_ptr>>, boost::shmem::flat_map_index<boost::shmem::IndexConfig>>::index_config<c har>". "boost/shmem/indexes/flat_map_index.hpp", line 29: Where: Specialized in boost::shmem::flat_map_index_aux<boost::shmem::detail::segment_manager<c har, boost::shmem::simple_seq_fit<boost::shmem::shared_mutex_family, boost::shmem::offset_ptr<void, boost::shmem::offset_1_null_ptr>>, boost::shmem::flat_map_index<boost::shmem::IndexConfig>>::index_config<c har>>. "boost/shmem/indexes/flat_map_index.hpp", line 45: Where: Specialized in boost::shmem::flat_map_index<boost::shmem::detail::segment_manager<char, boost::shmem::simple_seq_fit<boost::shmem::shared_mutex_family, boost::shmem::offset_ptr<void, boost::shmem::offset_1_null_ptr>>, boost::shmem::flat_map_index<boost::shmem::IndexConfig>>::index_config<c har>>. "boost/shmem/detail/segment_manager.hpp", line 1046: Where: Specialized in boost::shmem::detail::segment_manager<char, boost::shmem::simple_seq_fit<boost::shmem::shared_mutex_family, boost::shmem::offset_ptr<void, boost::shmem::offset_1_null_ptr>>, boost::shmem::flat_map_index<boost::shmem::IndexConfig>>::header_t. "boost/shmem/detail/segment_manager.hpp", line 1053: Where: Specialized in boost::shmem::detail::segment_manager<char, boost::shmem::simple_seq_fit<boost::shmem::shared_mutex_family, boost::shmem::offset_ptr<void, boost::shmem::offset_1_null_ptr>>, boost::shmem::flat_map_index<boost::shmem::IndexConfig>>. "boost/shmem/detail/named_object_impl.hpp", line 73: Where: Specialized in boost::shmem::detail::basic_named_object_impl<char, boost::shmem::simple_seq_fit<boost::shmem::shared_mutex_family, boost::shmem::offset_ptr<void, boost::shmem::offset_1_null_ptr>>, boost::shmem::flat_map_index<boost::shmem::IndexConfig>>. "boost/shmem/named_shared_object.hpp", line 42: Where: Specialized in boost::shmem::basic_named_shared_object<char, boost::shmem::simple_seq_fit<boost::shmem::shared_mutex_family, boost::shmem::offset_ptr<void, boost::shmem::offset_1_null_ptr>>, boost::shmem::flat_map_index<boost::shmem::IndexConfig>>. "Signaling.h", line 52: Where: Specialized in non-template code. 1 Error(s) and 1 Warning(s) detected. The offending bit of code is: void sendPathAndName(std::string &path, std::string &name, boost::shmem::named_shared_object *pSegment) { if(mpPath != NULL) { pSegment->deallocate(mpPath.get()); // <-- error } Where mpPath is a boost::shmem::offset_ptr<char> that was created with pSegment->allocate() -------------------- Trevor R.H. Clarke tclarke at ball.com <mailto:tclarke@ball.com> Ball Aerospace & Technologies Corp

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Re: [Boost-users] converting value before inserting into a list
by Flex Ferrum 20 Sep '06

20 Sep '06

Hello, Alexander Shyrokov, You wrote: > I want to convert values according to a map before inserting it into the > list. What is a proper way to do that? > I have this: > map<int,int> m; > vector<int> a,b; > for(vector<int>const_iterator i=a.begin();i!=a.end();++i) > b.push_back(m[*i]); > I could use std::copy with std::back_inserter to add elements to b, but > how do I convert it first? Should I write my own version of > back_inserter for that? > copy(a.begin(),a.end(),my_back_inserter(b,m)); > Thanks. Try this: #include <boost/lambda/lambda.hpp> using namespace boost; using namespace boost::lambda; //... //... map<int,int> m; vector<int> a,b; std::transform(a.begin(), a.end(), std::back_inserter(b), var(m)[_1]); Flex

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[MultiIndex] comparison operator
by Lukasz Dobrek 20 Sep '06

20 Sep '06

Hi, I know that there are for sure important design decisions explaining why all std containers as well as multiindex take a comparison operator, as template parameter. This behavior is satisfactory as long, as comparison is sort of context independent. The best example say ints, but there exist cases when comparison of two object requires some priory knowledge about context this objects exist in. My favorite example is tenor ( time period ). It is impossible to say whether 1 month is less then 30 days unless you know when you start counting. So in order to compare such objects I need to specify some anchor date. Unfortunately I cannot have a std::set of such objects, nor a multiindex indexed with this objects. Note: I am able to sort a vector of such objects using std::sort. First question: Is there a way to use such objects with multiindex, if not why? Second question: I cannot be the only bloke disturbed by this issue, how are you dealing with it? Regards, Lukasz Dobrek

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[Boost][Graph] Reversing a directed edge
by Young, Michael 20 Sep '06

20 Sep '06

I am a newbie to BGL - actually, I'm just beginning to build examples with it. However, I have read the first 4 chapters of "the book", and I've searched the documentation, and I haven't seen a way to reverse a specific edge within a directed (bidirectional) graph. Is there anyway to do this without removing the original edge and then adding the "reversed" edge? I have an application that requires such a "flip" of particular edges at times, but remove/add seems to be a bit "heavyweight" in terms of computation, especially when I already have identified the edge and have it accessible via an iterator. Thanks, Mike

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Re: [Boost-users] [graph] breadth_first_search with a structure
by boost＠daniel-gohlke.de 20 Sep '06

20 Sep '06

Hello Stephan, with your example I get the same errors like before. The compiler is Visual C++ 6.0 and the version number ob boost is (probably) 1.33.1. The first errors I get are: H:\daten\Programme\boost/pending/property.hpp(40) : error C2039: 'kind' : is not a member of '`global namespace'' H:\daten\Programme\boost/graph/properties.hpp(198) : see reference to class template instantiation 'boost::property_kind<long dreiDmatrix::Vertex::*>' being compiled H:\daten\Programme\Matrizen\dreiDmatrix.h(78) : see reference to class template instantiation 'boost::property_map<class boost::adjacency_list<struct boost::vecS,struct boost::vecS,struct boost::undirectedS,struct dreiDmatrix::Vertex,struct boost::no_property,struct boost::no_property,struct boost::listS>,long dreiDmatrix::Vertex::*>' being compiled This error is several times repeated. CU Daniel Am 12.09.2006 um 17:36 Uhr haben Sie geschrieben: > Please try this one (it's the altered bfs-example): > > #include <boost/graph/adjacency_list.hpp> > #include <boost/graph/breadth_first_search.hpp> > #include <boost/pending/integer_range.hpp> > #include <iostream> > > using namespace boost; > > //tag for throwing inside bfs_distance_visitor > struct max_distance_reached{}; > template < typename DistanceMap > > class bfs_distance_visitor:public default_bfs_visitor { > typedef typename property_traits < DistanceMap >::value_type T; > > public: > bfs_distance_visitor(DistanceMap dmap, T > max_distance):m_distance_map(dmap),m_max_distance(max_distance){ } > template < typename Edge, typename Graph > > void tree_edge(Edge e, const Graph & g) const > { > typename graph_traits < Graph >::vertex_descriptor > s = source(e, g), t = target(e, g); > m_distance_map[t] = m_distance_map[s] + 1; > if (m_distance_map[t] >= m_max_distance) > throw max_distance_reached(); > } > DistanceMap m_distance_map; > T m_max_distance; > }; > > //own vertex, bundles properties style > struct Vertex{ > long distance; > double probability; > }; > > int > main() > { > // Select the graph type we wish to use > typedef adjacency_list < vecS, vecS, undirectedS, Vertex> graph_t; > // Set up the vertex IDs and names > enum { r, s, t, u, v, w, x, y, N }; > // Specify the edges in the graph > typedef std::pair < int, int >E; > E edge_array[] = { E(r, s), E(r, v), E(s, w), E(w, r), E(w, t), > E(w, x), E(x, t), E(t, u), E(x, y), E(u, y) > }; > > // Create the graph object > const int n_edges = sizeof(edge_array) / sizeof(E); > typedef graph_traits<graph_t>::vertices_size_type v_size_t; > graph_t g(edge_array, edge_array + n_edges, v_size_t(N)); > > // Typedefs > typedef graph_traits < graph_t >::vertex_descriptor vertex_descriptor ; > typedef graph_traits < graph_t >::vertices_size_type vertices_size_type; > > // get the distance property map from the graph > typedef property_map<graph_t, long Vertex::*>::type tDistanceMap; > tDistanceMap distance_map = get(&Vertex::distance, g); > > //create a bfs visitor which calculates all distances smaller than 3 > bfs_distance_visitor<tDistanceMap> vis(distance_map, 3); > try{ > breadth_first_search(g, vertex(s, g), visitor(vis)); > } catch(max_distance_reached& ){} > return EXIT_SUCCESS; > } > > If this won't compile, please specify also which version of boost and > VC++ you are using. > > HTH, > Stephan > _______________________________________________ > Boost-users mailing list > <a href='email_neu.php?writeTo=Boost-users(a)lists.boost.org'>Boost-users(a)lists.boost.org</a> > <a href='http://lists.boost.org/mailman/listinfo.cgi/boost-users<br' target='_blank'>http://lists.boost.org/mailman/listinfo.cgi/boost-users<br</a> /> > > >

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program_options, description string formatting question
by Ed Johnson 20 Sep '06

20 Sep '06

Hi, Is it possible to generate a description in the following format using program_options? It is a more compact format than the program_options default. It helps keep the left hand column's max length smaller, thus preventing some excess wrapping in the description column. Compact format: [-h/--help] display usage [-p/--purpose arg] model-selection or prediction [model-selection] -d/--drug arg HIV drug to be tested [-t/--thresholds arg] low and high thresholds for drug resistance Please use only one or two values. [10] Program Options Default: -h [ --help ] display usage -p [ --purpose ] arg (=model-selection) model-selection or prediction -d [ --drug ] arg HIV drug to be tested -t [ --thresholds ] arg Thresholds for high and low resistance . Please use only 1 thresholds. In the compact case, drug is a required option, but the others are optional. So, drug does not get brackets. Also, default arguments are placed brackets at the end of the descriptor. Such as, [10] for thresholds Thanks, Ed

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Boost.Wave compiling issue
by Edmond Gheury 20 Sep '06

20 Sep '06

Hi, when trying to compile Boost.Wave (1.33.1) on AIX with VACPP 6. I got an error located in the file \boost\wave\cpplexer\re2clex\cpp_re2c_lexer.hpp, line 307, i.e. lexer<IteratorT, PositionT> lexer; First, it seems strange that a variable name matches a type name (and that's what's teeling the error message). When I replace that variable name by "lexer_" and its three remaining occurences in the "lex_functor" class, there's no more errors. So, I wonder if it is a bug popping up only on some compilers and, btw, can someone give me an explanation of how it manages to compile on msvc and g++. Thank you very much. Regards, Edmond

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[bind] Problem when bind a templated member function
by Christian Henning 19 Sep '06

19 Sep '06

Hi there, I know it must be very easy but I cannot figure it out myself. Can somehow please take a look at: class task { public: template < class T > void do_it( const T t ) { thread_ptr.reset( new boost::thread( boost::bind( (void (thread::*)(const T)) &thread::_run , this ))); } private: template < class T > void _run( const T t ) {} private: typedef boost::shared_ptr< boost::thread > thread_ptr_t; thread_ptr_t thread_ptr; }; There must be something wrong. I'm using VC2003. The comiler tells me: c:\boost\boost\bind\bind_template.hpp(18) : error C2091: function returns function Thanks ahead, Christian

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Global mutex and boost.thread
by Daher 19 Sep '06

19 Sep '06

I need to perform disk activity to a shared file across multiple instances of my program... my program was originally written using windows API and I'm porting it to other systems. and I'm using boost.thread for my threads.. Any way to create a global mutex? on windows all you need to do is provide "Global\" Prefix to the mutex name. Any ideas will be appreciated. Thanks in advanced. Dee

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converting value before inserting into a list
by Alexander Shyrokov 19 Sep '06

19 Sep '06

I want to convert values according to a map before inserting it into the list. What is a proper way to do that? I have this: map<int,int> m; vector<int> a,b; for(vector<int>const_iterator i=a.begin();i!=a.end();++i) b.push_back(m[*i]); I could use std::copy with std::back_inserter to add elements to b, but how do I convert it first? Should I write my own version of back_inserter for that? copy(a.begin(),a.end(),my_back_inserter(b,m)); Thanks. -- Regards, Alexander. http://sjcomp.com

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Re: [Boost-users] converting value before inserting into a list
by Hughes, James 19 Sep '06

19 Sep '06

> -----Original Message----- > From: boost-users-bounces(a)lists.boost.org > [mailto:boost-users-bounces@lists.boost.org] On Behalf Of > Alexander Shyrokov > Sent: 19 September 2006 14:19 > To: boost-users(a)lists.boost.org > Subject: [Boost-users] converting value before inserting into a list > > I want to convert values according to a map before inserting > it into the list. What is a proper way to do that? > I have this: > > map<int,int> m; > vector<int> a,b; > > for(vector<int>const_iterator i=a.begin();i!=a.end();++i) > b.push_back(m[*i]); > > I could use std::copy with std::back_inserter to add elements > to b, but how do I convert it first? Should I write my own > version of back_inserter for that? > > copy(a.begin(),a.end(),my_back_inserter(b,m)); > > Thanks. > -- > Regards, > Alexander. http://sjcomp.com > _______________________________________________ I probably being very anti-modern C++ here, but I think that the for loop takes a lot of beating for readability......its probably the most efficient too (with a bit of cacheing of invarients)...... I do find that some of these so called 'helpers' do make the code more obscure, but that's perhaps because I have spent 15 years doing C then C++, rather than solely starting with C++. James > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users > This message (including any attachments) contains confidential and/or proprietary information intended only for the addressee. Any unauthorized disclosure, copying, distribution or reliance on the contents of this information is strictly prohibited and may constitute a violation of law. If you are not the intended recipient, please notify the sender immediately by responding to this e-mail, and delete the message from your system. If you have any questions about this e-mail please notify the sender immediately.

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Re: [Boost-users] [serialization] Purpose of load_construct_data (was: Re: Library Interface Design)
by JOAQUIN LOPEZ MU?Z 19 Sep '06

19 Sep '06

Hello Robert, ----- Mensaje original ----- De: Robert Ramey <ramey(a)rrsd.com> Fecha: Sábado, Septiembre 16, 2006 9:00 am Asunto: Re: [Boost-users] [serialization] Purpose of load_construct_data (was: Re: Library Interface Design) > > I am not sure. I'm a little puzzled about the intended purpose of > > load_construct_data, as the docs and the code of Boost.Serialization > > seem to suggest that it is used for two incompatible tasks: > > > > a) to construct a dummy object prior to deserialization itself, thus > > providing a user-overridable hook in case default construction > is not > > appropriate. > > b) to deserialize in place as explained on the bit you quote. > > > > The intended purpose was to address de-serialization of objects > that have no default constructor. See test_non_default_ctor. > > > My hunch is that Robert started this with b) in mind but finally the > > facility was kept playing a more humble role as a). Consider for > > instance, serialization of pointers: currently, if an object > instance> is saved exclusively through pointers, > Boost.Serialization does the > > following when the first such > > pointer is met > > > > save_construct_data(ar,p); // S(0) > > ar<<*p; // S(1) > > > > and correspondingly at loading time > > > > p=get unitialized storage; > > load_construct_data(ar,p); // L(0) > > ar>>*p; // L(1) > > > > By default save_construct_data does nothing and load_construct_data > > creates a default cted object, effectively leading to a two-phase > > construction scenario. Now, if the user decides to override > > (save|load)_construct_data > > for some class, say foo, so as to perform one-phase construction, > > we've got the following: > > > > S(0) saves foo contents > > S(1) saves foo contents again > > Nope. save_construct_data saves ONLY that data needed for > constructionwhile ar << *p save that data NOT used in construction. > > > L(0) loads foo contents and creates a foo object with these. > > L(1) loads foo contents again > > Nope - see above. > > I believe this is well illustrated by the > test_non_default_ctor.cpp example > previously cited. > > Note that in generally, the data required to construct an instance > might not > be part of the instance itself. This is also addressed by this api. > > I'm not sure, but I suspect this could be also useful in de- > serializationof objects which contain references to other objects > as references can > only be set at object construction time. Tracking would still work. > Thanks for pointing me to test_non_default_ctor.cpp. I think this example nicely illustrates the purposes which (load|save)_construct_data is meant to serve, and that you've summarized in your comments above: * handle types without a default ctor. * serialize data used at construction time which are *not* serialized by T::serialize. and this is all good, but if I'm understanding you right then you're stating (in agreement with my analysis) that (load|save)_construct_data can't be used for one-phase serialization, and that two phases (construction and serialization) are still needed. The original post by Dave said otherwise, though, and I think the misunderstanding comes from the example at http://boost.org/libs/serialization/doc/serialization.html#constructors where my_class serializes my_class::m *both* at my_class::serialize *and* my_class::(load|save)_construct_data. If the analysis I develop in my previous post is correct (is it?) this leads to my_class::m being serialized *twice* when a pointer to my_class is saved. Maybe it would sufice to rewrite this part of the documentation with a more sensible example like the one at test_non_default_ctor.cpp. What do you think? > Robert Ramey Thank you, Joaquín M López Muñoz Telefónica, Investigación y Desarrollo

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In reply to: " edge function"
by Tom Lenaerts 19 Sep '06

19 Sep '06

Hi stephan, sorry about the lack of detail in my question. Below you can find the code for a network factory class. The code reads a file (like this) 300 0 37 0 1 2 3 4 5 6 8 9 15 17 21 42 44 51 56 63 66 77 84 86 93 123 126 128 129 151 153 163 164 170 219 225 240 247 261 288 290 1 12 0 0 2 11 18 33 47 66 95 127 192 209 211 2 51 0 1 0 3 5 6 7 8 10 12 13 14 15 16 17 19 25 27 31 35 36 38 49 78 79 81 84 88 91 93 104 111 139 156 169 175 178 188 203 208 223 227 243 247 249 253 255 266 267 268 282 286 3 8 0 2 0 4 29 42 55 62 257 4 11 0 3 0 18 34 52 59 108 139 216 235 296 5 14 0 2 0 26 50 56 58 71 74 80 186 191 193 194 283 6 14 0 0 2 7 16 30 34 46 57 101 141 174 198 215 291 7 6 0 2 6 67 82 97 181 ... and when the member function 'create' is called, the network should be returned. The error was a runtime error. I got the following answer from Xcode: [Session started at 2006-09-19 09:57:00 +0200.] #seed.in not found. Creating a new seed... seed = 583597 gamenetwork has exited due to signal 10 (SIGBUS). I examined your code and adapted mine to yours and noticed that the error disappears when I change g=new Graph(); to g=new Graph(1); in the member function parseFile. It seems that this is the error that I made (as I expected it is a silly one). Could you tell me why the '1' is required here? Thanks for the help Tom ==networkfact.h #ifndef __NETWORKFACTORY_H #define __NETWORKFACTORY_H #include "factory.h" #include <boost/graph/adjacency_list.hpp> #include <boost/graph/graph_traits.hpp> using namespace std; typedef boost::adjacency_list<boost::vecS, boost::vecS, boost::undirectedS> Graph; typedef Graph* Graphptr; typedef boost::graph_traits<Graph>::edge_descriptor Edge; typedef boost::graph_traits<Graph>::vertex_descriptor Vertex; typedef boost::graph_traits<Graph>::vertex_iterator Vertex_iterator; typedef boost::graph_traits<Graph>::edge_iterator Edge_iterator; typedef boost::graph_traits<Graph>::vertices_size_type Vertex_type; typedef boost::property_map<Graph, boost::vertex_index_t>::type IndexMap; typedef Factory<Graph> GraphFactory; // the factory creates new graph instances class NetworkFactory: public GraphFactory { public: NetworkFactory(string fname): _fname(fname){}; //the file contains a grpah specification. ~NetworkFactory(){}; Graphptr create(); private: Graphptr parseFile(istream&); void tokenize(const string&, vector<string>&, const string& delimiters = " "); void processTokens(vector<string>&, Graphptr); string _fname; }; typedef NetworkFactory* NetworkFactoryptr; #endif ==networkfact.cpp #include "networkfact.h" #include <boost/lexical_cast.hpp> #include <sstream> #include <fstream> Graphptr NetworkFactory::parseFile(istream& is){ char c; int numnodes=0; Graphptr g=NULL; while(!is.eof()){ c=is.get(); if(c=='#' || c == '\n'|| c == ' '){ string line; getline(is,line,'\n'); //ignore line content } else{ //it is not a comment line but useful information. is.putback(c); string line; getline(is,line,'\n'); //start parsing the line vector<string> tokens; tokenize(line,tokens); if(tokens.size() == 1){ numnodes= boost::lexical_cast<int>(tokens[0]); g=new Graph(1); } else { if(g!=NULL) processTokens(tokens,g); } } } return g; } void NetworkFactory::tokenize(const string& str, vector<string>& tokens, const string& delimiters){ // Skip delimiters at beginning. string::size_type lastPos = str.find_first_not_of(delimiters, 0); // Find first "non-delimiter". string::size_type pos = str.find_first_of(delimiters, lastPos); while (string::npos != pos || string::npos != lastPos) { // Found a token, add it to the vector. tokens.push_back(str.substr(lastPos, pos - lastPos)); // Skip delimiters. Note the "not_of" lastPos = str.find_first_not_of(delimiters, pos); // Find next "non-delimiter" pos = str.find_first_of(delimiters, lastPos); } } void NetworkFactory::processTokens(vector<string>& tokens, Graphptr g){ if(tokens.size()>=3){ int current = boost::lexical_cast<int>(tokens[0]); int numedges = boost::lexical_cast<int>(tokens[1]); Vertex first=boost::vertex(current,*g); for(int i=0;i<numedges;i++){ int other= boost::lexical_cast<int>(tokens[3+i]); //this has to be 3 because some other data is in position 2 Vertex second=boost::vertex(other,*g); pair<Edge, bool> result=boost::edge(first,second,*g); if(!result.second){ boost::add_edge(first,second,*g); } } } } Graphptr NetworkFactory::create(){ ifstream netwfile(_fname.c_str()); if(netwfile.is_open()){ Graphptr res= parseFile(netwfile); netwfile.close(); return res; } return NULL; }

2 1

BOOST_FOREACH and maps
by Rob Caldecott 18 Sep '06

18 Sep '06

OK, I know BOOST_FOREACH isn't part of the official (1.33.1) build yet, but hopefully some people here are using this excellent algorithm and can help me out... (note that I am using MS Visual Studio 2005): How can I use BOOST_FOREACH to iterate through a map? For example, the following won't build: std::map<int, int> m; BOOST_FOREACH(std::pair<int, int> p, m) { } I get the following error: warning C4002: too many actual parameters for macro 'BOOST_FOREACH' However, the following will work OK: std::map<int, int> m; std::pair<int, int> p; BOOST_FOREACH(p, m) { } But is there a way to declare the pair within the FOREACH loop? Note that I also tried the following, with no success: std::map<int, int> m; BOOST_FOREACH(std::map<int, int>::value_type p, m) { } A typedef also seems to work, e.g.: std::map<int, int> m; typedef std::pair<int, int> mpair; BOOST_FOREACH(mpair p, m) { } Can the pair be declared without a typedef? Is this a limitation of the MS compiler? Thanks in advance.

5 4

edge function
by Tom Lenaerts 18 Sep '06

18 Sep '06

This is again a newbie question. I want to create a graph based on some input file. I parse this file and in the code I want to check whether the link already exists int current=strToInt(tokens[0]); int numedges=strToInt(tokens[1]); for(int i=0;i<numedges;i++){ Vertex first=vertex(current,*g); int other=strToInt(tokens[3+i]); Vertex second=vertex(other,*g); pair<Edge, bool> result=boost::edge(first,second,*g); if(!result.second){ boost::add_edge(first,second,*g); } } tokens[0] is the id of the node, tokens[1] contains the number of edges this node is pointing to. From tokens[3] until the end, one gets the nodes to which the current node is connected (stored in other) As you can see I call the function boost::edge() to check whether there is already a link between first and second. As soon as I do this I get an error in Xcode. Does anyone know what I'm doing wrong here. It probably something very simple but I don't see it. Thanks in advance Tom

2 1

Boost.python iterator , range
by CT 18 Sep '06

18 Sep '06

Hi , Can someone can give me some help on how to expose correctly an array of object pointers using boost.python ? here is a small example of what i need i have a class class A { public: A(std::string &oName); ~A(){} const std::string &GetName() const; } class B { std::vector<*A> *poNames public: std::vector<*A> GetNames() { return *poNames } } assume that there is two instances of A in the container of the object B now for the boost::python code. I would like to be able to expose class a and class b and the vector of A* typedef std::vector<A*> array_proj; array_proj::iterator begin_array_proj(array_proj &x) {return x.begin();} array_proj::iterator end_array_proj(array_proj &x) {return x.end();} BOOST_PYTHON_MODULE(pysession) { class_<A>("object a",init<std::string &) .def("GetName",&A::GetName,return_value_policy <copy_const_reference>() ) ; class_<B>("object B") .def("GetNames", &B::GetNames, return_value_policy<manage_new_object>() ) ; class_<std::vector<*A> >("array of pointer to objects A") .def("__iter__", range( begin_array_proj, end_array_proj) ) ; } Now in python for example I call #create a new object B #and iterate over all of the object A #assume that there are two object of type A in the vector oNewSession = pysession.B() oVector = oNewSession.GetNames() for oA in oVector.__iter__(): print (oA.GetName()) i have this error when i start the python script for oA in oVector.__iter__(): TypeError: No to_python (by-value) converter found for C++ type: class ::A * Does someone can give me some help on how to expose correctly an array of pointers using boost.python ?

1 0

Dereferencing value for algorithm
by Alexander Shyrokov 18 Sep '06

18 Sep '06

An iterator is pointing to a pointer, how do I add another dereferencing operator in the algorithm, so it works on values? void f(int& i); vector<int*> a; // this would work if f would be void f(int* i) for_each(a.begin(),a.end(),boost::bind(f,_1)); I could define a dereferencing predicate: template<class T> struct deref{ typedef T result_type; T operator()(T* p){assert(p);return *p;} }; for_each(a.begin(),a.end(),boost::bind(f,boost::bind(deref<int>,_1))); but this requires supplying a template parameter. Is there an easier way? Thanks. -- Regards, Alexander. http://sjcomp.com

3 2

[multi_index].[example].[composite_keys]. Fails to compile with Solaris 10
by Prashant Thakre 18 Sep '06

18 Sep '06

Hi, OS: SunOS 5.10 >>CC -V CC: Sun C++ 5.8 Patch 121017-04 2006/08/02 I am trying to compile composite_keys.cpp with Sun Studio 11. After applying all the patches listed at http://developers.sun.com/prodtech/cc/downloads/ patches/ss11_patches.html, http://blogs.sun.com/roller/resources/sga/ boost_1_33_1.patch and following instructions listed at http://blogs.sun.com/ sga/entry/boost_1_33_1, am still unable to do so. However, I can compile other examples provided with multi_index. >>CC -library=stlport4 -features=tmplife -featurestmplrefstatic -fast -I$BOOST_INCLUDE composite_keys.cpp ----------------------------------------------------------------------------- boost/include/boost-1_33_1/boost/multi_index/ordered_index.hpp", line 784: Error: boost::multi_index::composite_key_compare<std::less<const file_entry*>, std::less<std::string>, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type>::operator()<boost::multi_index:: composite_key<file_entry, boost::multi_index::member<file_entry, const file_entry*, 21>, boost::multi_index::member<file_entry, std::string, 1>, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type,boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type>, boost::multi_index::composite_key<file_entry, boost::multi_index:: member<file_entry, const file_entry*, 21>, boost::multi_index::member<file_entry, std::string, 1>, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type>>(const boost::multi_index::composite_ key_result<boost::multi_index::composite_key<file_entry, boost::multi_index::member<file_entry, const file_entry*, 21>, boost::multi_index::member<file_entry, std::string,1>, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type>>&, const boost::multi_index::composite_key_result< boost::multi_index::composite_key<file_entry, boost::multi_index::member<file_entry, const file_entry*, 21>, boost::multi_index::member<file_entry, std::string, 1>, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type>>&) const is not accessible from boost::multi_index::detail::ordered_index<name_key, std::less<boost::multi_index::composite_key_result< boost::multi_index::composite_key<file_entry, boost::multi_index::member<file_entry, const file_entry*, 21>, boost::multi_index::member<file_entry, std::string, 1>, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::nulles::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type, boost::tuples::null_type>>>, boost::multi_index::detail::nth_layer<1,file_entry, boost::multi_index::indexed_by<boost::multi_index::ordered_unique<name_key, mpl_::na, mpl_::na>, boost::multi_index::ordered_non_unique< size_key, mpl_::na, mpl_::na>, mpl_::na,mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na, mpl_::na>, std::allocator<file_entry>> , boost::mpl::vector0<mpl_::na>, boost::multi_index::detail::ordered_unique_tag>::invariant_() const. ----------------------------------------------------------------------------- similar error is reported for line 785 ("boost/include/boost-1_33_1/boost/ multi_index/ordered_index.hpp" ) regards, Prashant Thakre

2 4

[program options] Using similar option strings
by Jason House 18 Sep '06

18 Sep '06

I recent attempted the equivalent of allowing the follwoing two options: --help --help-command [arg] --help-component [arg] When I ran the program with --help, I got an error that it was ambiguous. I didn't realize it, but program options allows the user to not specify the full string with "--". This then makes all the options above match --help. How can I get this type of functionality without getting runtime errors about ambiguity? If I were to reduce it to just --help and --help-command, it may be possible to just do --help with an optional argument, but I don't know how to do that. Currently, I'd like to avoid a shared namespace for commands and components.

2 1

Re: [Boost-users] Library Interface Design
by Sohail Somani 18 Sep '06

18 Sep '06

> -----Original Message----- > From: boost-users-bounces(a)lists.boost.org > [mailto:boost-users-bounces@lists.boost.org] On Behalf Of > Robert Kindred > > Can you not create them all, have them wait on some > condition variable > > and signal when you're ready to go? > > Yes, I suppose that works, with some extra effort. So does > this mean that a > monolithic constructor is very important to you? Not necessarily a monolithic constructor. Just before it starts doing work, you wait on the condition. I wouldn't expect that to be a ton of work. However, it is important to me to not have to remember the order in which to create things. This is just asking for a bug at 2am. Sohail

1 0

boost::interprocess::node_allocator & VC8 run-time problem
by alexmark 18 Sep '06

18 Sep '06

I have the problem with VC8 release build (all release build options - by default, i.e., optimization is "Maximize speed /O2" and so on). A run of "repro" output executable finishes with the exception on attempt to read data from address 0. I noticed it for boost::interprocess (and boost::shmem too) allocators of type: - node_allocator - cached_node_allocator and not to: - allocator - private_node_allocator The way out I found (for "problematic" allocator types) is to set additional compiler option "/Og-" (already declared deprecated). With VC7.1 it all is ok for any allocator type w/o setting /Og- or any other additional options. Have anyone noticed this problem? Where the problem originates from? VC8 optimization specifics (NRVO is affected by /Og option)? Or smth. wrong in "repro" code? Thanks. ////////////// The "repro" code is the following: #include "stdafx.h" #include <boost/interprocess/managed_external_buffer.hpp> #include <boost/interprocess/allocators/node_allocator.hpp> #include <boost/interprocess/containers/list.hpp> using namespace boost::interprocess; enum { A_SHARED_MEMORY_SIZE = 65536, A_POOL_SIZE = 64 }; typedef node_allocator<int, A_POOL_SIZE, managed_external_buffer::segment_manager> user_allocator_t; typedef list<int, user_allocator_t> MyUserList; int _tmain(int argc, _TCHAR* argv[]) { static char static_buffer[A_SHARED_MEMORY_SIZE]; managed_external_buffer user_buffer(create_only, static_buffer, A_SHARED_MEMORY_SIZE); MyUserList *userlist = user_buffer.construct<MyUserList>("MyUserList")(user_buffer.get_segment_manager()); return 0; }

2 1

Memory leask in class thread.
by 蹬三轮的 18 Sep '06

18 Sep '06

I found a memory leak in boost's thread class. Here is the sample program: void func() { } int _tmain(int argc, _TCHAR* argv[]) { _CrtSetReportMode(_CRT_WARN, _CRTDBG_MODE_DEBUG); _CrtSetReportMode(_CRT_ERROR, _CRTDBG_MODE_DEBUG); _CrtSetReportMode(_CRT_ASSERT, _CRTDBG_MODE_DEBUG); { thread t(func); t.join(); } _CrtDumpMemoryLeaks(); return 0; } The output is: The thread 'Win32 Thread' (0xb24) has exited with code 0 (0x0). Detected memory leaks! Dumping objects -> {188} normal block at 0x003A9DA8, 24 bytes long. Data: < - > D0 2D 15 00 FF FF FF FF 00 00 00 00 00 00 00 00 {187} normal block at 0x003A9C78, 8 bytes long. Data: < : > A8 9D 3A 00 01 CD CD CD Object dump complete. So I think boost should resolve this problem in the next version.

5 5

Pb with Boost and VC++7.1 : inconsistent code ?
by Washburn 18 Sep '06

18 Sep '06

Hello everyone. I'm new to this mailing-list but I have a very annoying and urgent problem concerning Boost and the STL. I just upgraded to Boost 1.33.1 which is needed for the new version of libtorrent, linked statically in one of my DLLs. Build of Boost went quite well (using BJam) Build of lib went OK. Build of DLL : no problem either. But then at runtime I get this : Unhandled exception at 0x77e79282 in TestFileDl.exe: Microsoft C++ exception: boost::filesystem::filesystem_error @ 0x0012d654. Exception thrown in [path_posix_windows.cpp] line 339 : if ( !checker( name ) ) { boost::throw_exception( filesystem_error( "boost::filesystem::path", "invalid name \"" + name + "\" in path: \"" + src + "\"" ) ); } ... because this check does not behave properly : BOOST_FILESYSTEM_DECL bool windows_name( const std::string & name ) { return name.size() != 0 && name.find_first_of( windows_invalid_chars ) == std::string::npos <-------------- (here) && *(name.end()-1) != ' ' && (*(name.end()-1) != '.' || name.length() == 1 || name == ".."); } ... because find_first_of does not return what it should, in [xstring] : size_type find_first_of(const _Elem *_Ptr, size_type _Off, size_type _Count) const { // look for one of [_Ptr, _Ptr + _Count) at or after _Off if (0 < _Count && _Off < _Mysize) { // room for match, look for it const _Elem *const _Vptr = _Myptr() + _Mysize; for (const _Elem *_Uptr = _Myptr() + _Off; _Uptr < _Vptr; ++_Uptr) if (_Traits::find(_Ptr, _Count, *_Uptr) != 0) return (_Uptr - _Myptr()); // found a match } return (npos); // no match } Obviously the std::string is screwed up here, because I think _Mysize should not be 31, which makes the [for] searche outside the boudaries of the buffer, thus returning the wrong results... + this 0x0012d854 {"main_session.log"} const std::basic_string<char,std::char_traits<char>,std::allocator<char> > * const _Mysize 31 unsigned int I also believe that the symbol table is wrong here but I'm not sure. This piece of code belongs to the libtorrent project and is supposed to be stable. Then it gets even worse : after the acual throwing of the exception (the "throw" instruction), my call stack is screwed with a call to feeefeee()... I tried all compilation and link options, getting always the same result. Any idea people ? Please help :( Washburn

3 2

Re: [Boost-users] Library Interface Design
by Sohail Somani 18 Sep '06

18 Sep '06

> -----Original Message----- > From: boost-users-bounces(a)lists.boost.org > [mailto:boost-users-bounces@lists.boost.org] On Behalf Of > Robert Kindred > I can think of one example for not fully constructing objects: [snip] > The problem is in starting up. If each one of these threads > knows about > each other via some method (pointer, or reference), then when > a thread > starts up its own business, whatever that is, then most > likely it will start > generating data and sending messages. When it tries to send > a message to a > thread that does not yet exist, BOOM!!! (yes, I have > experienced this boom). Can you not create them all, have them wait on some condition variable and signal when you're ready to go?

2 1

Re: [Boost-users] Boost serialization : concurrency
by Moshe Matitya 18 Sep '06

18 Sep '06

Daniel F. Savarese wrote: > ... > However, I think I have a workaround that I just finished > testing (at least the unit tests no longer seg fault). > If you're willing to waste some memory and add the equivalent > of the following to oserializer > > private: > static oserializer & dummy; > > static oserializer & _instantiate(){ > static oserializer instance; > return instance; > } > public: > static oserializer & instantiate(){ > return dummy; > } > > and to iserializer: > > private: > static iserializer & dummy; > > static iserializer & _instantiate(){ > static iserializer instance; > return instance; > } > public: > static iserializer & instantiate(){ > return dummy; > } > > and initialize oserializer::dummy as: > template<class Archive, class T> oserializer<Archive,T> & > oserializer<Archive,T>::dummy = > oserializer<Archive,T>::_instantiate(); > > and iserializer::dummy as: > template<class Archive, class T> iserializer<Archive,T> & > iserializer<Archive,T>::dummy = > iserializer<Archive,T>::_instantiate(); > > then the local static will be initialized at program initialization > before any threads are running without incurring the global variable > initialization ordering problem. > ... > This is just a test hack, but I think the concept works. Sorry, I don't think your idea works: (1) What happens if the constructor or initializer of a global or static member variable calls oserializer::instantiate(), and that variable is initialized before oserializer::dummy is initialized? E.g.: struct foo { foo() { // oserializer::dummy might not be initialized yet, // so this can return a reference to an invalid object: oserializer<x,y> os = oserializer::instantiate(); os.do_something(); // boom } }; foo g_f; (2) There exists no guarantee that multiple threads will not be running at program initialization time. Threads can be started in the constructors and initializers of global or static member variables. E.g.: void thread_func() { // oserializer::dummy might not be initialized yet, // so this can return a reference to an invalid object: oserializer<x,y> os = oserializer::instantiate(); os.do_something(); // boom again } struct bar { bar() { boost::thread t(&thread_func); } } bar g_b; (Btw, if your idea really did work, then you would have just invented a thread-safe implementation of the Singleton pattern that does not require any thread synchronization. I don't believe that's possible.) Moshe

1 0

[Boost.Signal] Single-shot Connection?
by Wu Yinghui, Freddie 18 Sep '06

18 Sep '06

Dear all, I sent in this on 14 Sept, but have received no reply so far. As I'm not sure if it was lost in the void, I'm resend the mail again. Please bear with me if you have received the same question before. > I'm a happy user of Boost.Signal, as it brings great power to our > software design in terms of loosening all the coupling between > components. > > However, I recently come across a case where a single-shot slot is > desired (i.e., a signal-slot connection that is automatically > disconnected once the signal is invoked for once). In our current > implementation, we have to keep boost::signals::connection object around > with the slot implementation, so that it can disconnect it after the first invocation. > > However, we have this problem of boost::signals::connection management, > since one signal may be connected to different signals and we have > problem identifying the correct connection to be disconnected. So my > question is: Is there any easier way (i.e., ways that doesn't involve > the implementation of the slot function itself) that I can add a > single-shot signal-slot connection? > > Any suggestion is appreciated. Cheers, Freddie -- Wu Yinghui, Freddie Research & Development Senior Software Engineer Volume Interactions Pte Ltd 1 Kim Seng Promenade, #12-01 Great World City East Tower Singapore 237994 Tel: +65 62226962 (Ext 216) Fax: +65 62226215 Email: yhwu(a)volumeinteractions.com URL: http://www.volumeinteractions.com Important: This message is intended for the recipient(s) addressed above. It contains privileged and confidential information. If you are not the intended recipient, please notify the sender immediately by replying to this message and then delete it from your system. You must not read, copy, use, or disseminate this communication in any form. Thank you.

1 0

Re: [Boost-users] Boost serialization : concurrency (was Possibletoappend...)
by Robert Ramey 18 Sep '06

18 Sep '06

Hmmm - well that is interesting. I believe I used this idiom in order to address a problem where global static variables couldn't be guarenteed to be instantiated in a particular order and this was the fix recommended. So now what do we do? Robert Ramey Daniel F. Savarese wrote: > In message <eek3v5$hbk$1(a)sea.gmane.org>, "Robert Ramey" writes: >> So now you know my intention - and I believe that the code reflects >> that. > > Here's what's happening with > static oserializer & instantiate(){ > static oserializer instance; > return instance; > } > Thread 1 calls instantiate and is pre-empted in the middle of > constructing instance the first time control passes through its > declaration. Thread 2 then calls instantiate and returns a > reference to an incompletely constructed instance. Then thread 2 > bombs in basic_oarchive_impl::save_object the first time it tries to > dereference the object to invoke a virtual function > (in this case class_info()) of an incompletely constructed object > (i.e., no virtual function table). And now I'm reminded why whenever > I see a static local variable I have the knee-jerk reaction: > "not thread-safe." I had to reeducate myself by exercising the > debugger and revisiting what the C++ standard has to say about > the initialization of static storage. > > daniel > > -#-#-#-#-| Sleep and The Traveller |-#-#-#-#-#-#-#- > http://www.savarese.org/ In distant lands, I hear the call of my > home. # s a v a r e s e > Yet my work is not done. My journey's just begun.- software > research -- http://www.sleepandthetraveller.com/ # > http://www.savarese.com/

1 0

[boost::serialization]: Dies with access violation (segfaults) reading beyond the end of archive.
by Konstantin Andreev 18 Sep '06

18 Sep '06

When 1) trying to restore from archive the pointer to sample class, and 2) archive is over at this moment boost::serialization causes Access Violation Fault in file: basic_iarchive.cpp, line 470: bpis_ptr = co.bpis_ptr; The code to reproduce the fault follows. -- Konstantin Andreev. ------------------------( cut here )---------------------- #include <iostream> #include <sstream> #include <boost/archive/text_iarchive.hpp> #include <boost/archive/text_oarchive.hpp> class Sample { private: int pod_int; std::string pod_str; template<class Archive> void serialize(Archive & ar, const unsigned int ){ ar & pod_int & pod_str; }; friend class boost::serialization::access; friend std::ostream & operator<<(std::ostream & os, const Sample & sa ); public: Sample() {}; Sample( int _i, std::string _s ) : pod_int( _i), pod_str( _s ) {}; }; BOOST_CLASS_TRACKING(Sample, track_never) BOOST_CLASS_VERSION(Sample, 19) std::ostream & operator<<(std::ostream & os, const Sample & sa ) { return os << "-- int: " << sa.pod_int << ", str: >" << sa.pod_str << "< at 0x " << &sa << '\n'; } int main( void ) { Sample *obj_to = NULL; const Sample * const obj_fr = new Sample( 55, "**** test string *****" ); std::cout << *obj_fr; std::stringstream archbuf; boost::archive::text_oarchive *oa = new boost::archive::text_oarchive( archbuf, 3 ); *oa << obj_fr; std::cout << "-- archive content: >" << archbuf.str() << "<\n"; delete oa; boost::archive::text_iarchive *ia = new boost::archive::text_iarchive( archbuf, 3 ); *ia >> obj_to; std::cout << *obj_to; /////////////////////////////////// *ia >> obj_to; // ARCHIVE IS OVER. BOOM !!! /////////////////////////////////// std::cout << *obj_to; delete ia; return 0; }

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[serialization] serialization of pointers to primitive types?
by Joaquín Mª López Muñoz 17 Sep '06

17 Sep '06

The following test program: #include <boost/archive/text_oarchive.hpp> #include <sstream> int main() { int x=0; int* const px=&x; std::ostringstream oss; boost::archive::text_oarchive oa(oss); oa<<px; return 0; } produces this error in MSVC++ 6.0: ...boost/serialization/access.hpp(109) : error C2228: left of '.serialize' must have class/struct/union type ...boost/serialization/serialization.hpp(81) : see reference to function template instantiation 'void __cdecl boost::serialization::access::serialize( class boost::archive::text_oarchive &,int &,const unsigned int)' being compiled and the following error in GCC 3.2: ...boost/serialization/access.hpp: In static member function `static void boost::serialization::access::serialize(Archive&, T&, unsigned int) [with Archive = boost::archive::text_oarchive, T = int]': ... ...boost/serialization/access.hpp:109: request for member `serialize' in `t', which is of non-aggregate type `int' I've checked the same snippet against Boost 1.33.1, CVS HEAD and RC_1_34_0, using other primitive types like std::string, same problem always. Same problem also for the loading counterpart. When the pointed-to type is not primitive, though, everything works fine, regardless of whether the type has intrusive or non intrusive serialization support. I am sure I'm doing something really stupid here, but I've been banging my head against this several hours. Some clue greatly appreciated. Thank you, Joaquín Mª López Muñoz Telefónica, Investigación y Desarrollo

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[timer] Comments do not match the implementation?
by KSpam 17 Sep '06

17 Sep '06

I would like to use boost::timer to replace a timing object from another library. In looking into the header file, I noticed the following comments: // It is recommended that implementations measure wall clock rather than CPU // time since the intended use is performance measurement on systems where // total elapsed time is more important than just process or CPU time. All is well and good I thought to myself ... wall clock is exactly what I want! But alas, the implementation just wraps std::clock(). The man page for clock states the following: "The clock() function returns an approximation of processor time used by the program." In summary, the header states that the timer implementation should use wall clock time, but it ignores its own advice and uses processor time. I'm confused. Do I need to create my own timer implementation in order to use wall clock time? Thanks, Justin

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Re: [Boost-users] Boost serialization : concurrency (was Possibleto append...)
by Robert Ramey 17 Sep '06

17 Sep '06

So now you know my intention - and I believe that the code reflects that. I'm guessing that the key might be that the DLL gets unloaded "too soon" so that we get a seg fault by invoking code that is no longer in memory. But as you have discovered - this is very problematic to track down and could be a subtle error of my own, an error in the language support system (loading/unloading DLLS). Overzealous optimization on the compiler's part or something else entirely. Sorry I can't be of more help. Good Luck Robert Ramey

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[asio] Strange compilation error
by Christian Henning 17 Sep '06

17 Sep '06

Hi there I'm experiencing a strange compilation error that I cannot resolve myself. The following non-functionating triggers the error. I'm using VC2003 SP1. The error is due to the write() call. template <class T > void sent( const T& object ) { std::ostringstream archive_stream; boost::archive::binary_oarchive archive( archive_stream ); archive & object; std::string outbound_data = archive_stream.str(); // Format the header. std::ostringstream header_stream; header_stream << std::setw( 8 ) << std::hex << outbound_data.size(); std::string outbound_header = header_stream.str(); // Write the serialized data to the socket. We use "gather-write" to send // both the header and the data in a single write operation. std::vector<boost::asio::const_buffer> buffers; buffers.push_back(boost::asio::buffer(outbound_header)); buffers.push_back(boost::asio::buffer(outbound_data)); boost::asio::write( socket, buffers ); } This is the verbose error message: ..\..\..\External\Includes\Boost\asio\impl\write.ipp(40) : error C2825: 'Sync_Write_Stream::error_type': cannot form a qualified name ..\..\..\External\Includes\Boost\asio\impl\write.ipp(58) : see reference to function template instantiation 'size_t boost::asio::write<Sync_Write_Stream,Const_Buffers,boost::asio::detail::transfer_all_t,boost::asio::detail::throw_error_t>(Sync_Write_Stream (__stdcall &),const Const_Buffers &,Completion_Condition,Error_Handler)' being compiled with [ Sync_Write_Stream=SOCKET (int,int,int), Const_Buffers=std::vector<boost::asio::const_buffer>, Completion_Condition=boost::asio::detail::transfer_all_t, Error_Handler=boost::asio::detail::throw_error_t ] SendImages.cpp(75) : see reference to function template instantiation 'size_t boost::asio::write<SOCKET(int,int,int),std::vector<_Ty>>(Sync_Write_Stream (__stdcall &),const Const_Buffers &)' being compiled with [ _Ty=boost::asio::const_buffer, Sync_Write_Stream=SOCKET (int,int,int), Const_Buffers=std::vector<boost::asio::const_buffer> ] ..\..\..\External\Includes\Boost\asio\impl\write.ipp(40) : error C2039: 'error_type' : is not a member of 'operator``global namespace''' ..\..\..\External\Includes\Boost\asio\impl\write.ipp(40) : error C2146: syntax error : missing ';' before identifier 'e' ..\..\..\External\Includes\Boost\asio\impl\write.ipp(40) : error C2065: 'e' : undeclared identifier ..\..\..\External\Includes\Boost\asio\impl\write.ipp(41) : error C2228: left of '.write_some' must have class/struct/union type type is '__w64 unsigned int (__stdcall &)(int,int,int)' ..\..\..\External\Includes\Boost\asio\impl\write.ipp(41) : error C3861: 'e': identifier not found, even with argument-dependent lookup ..\..\..\External\Includes\Boost\asio\impl\write.ipp(44) : error C3861: 'e': identifier not found, even with argument-dependent lookup ..\..\..\External\Includes\Boost\asio\impl\write.ipp(46) : error C3861: 'e': identifier not found, even with argument-dependent lookup ..\..\..\External\Includes\Boost\asio\impl\write.ipp(50) : error C2825: 'Sync_Write_Stream::error_type': cannot form a qualified name ..\..\..\External\Includes\Boost\asio\impl\write.ipp(50) : error C2039: 'error_type' : is not a member of 'operator``global namespace''' ..\..\..\External\Includes\Boost\asio\impl\write.ipp(50) : error C2146: syntax error : missing ';' before identifier 'e' ..\..\..\External\Includes\Boost\asio\impl\write.ipp(50) : error C3861: 'e': identifier not found, even with argument-dependent lookup ..\..\..\External\Includes\Boost\asio\impl\write.ipp(51) : error C3861: 'e': identifier not found, even with argument-dependent lookup Thanks ahead, Christian

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Need help with boost and dev-c++
by Craig Ritzdorf 17 Sep '06

17 Sep '06

I'm having a problem using any part of boost in dev-c++. The compiler itself seems to handle the code fine but when it trys to link i get the error: [Linker error] undefined reference to 'boost::filesystem::path::path(char const*)' I looked through the archive and found someone else (Chun Ping Wang) with this same problem but it was never answered. Thanks Craig

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[function_types][review schedule] new version released
by Tobias Schwinger 17 Sep '06

17 Sep '06

Dear Boost community, a new version of the FunctionTypes candidate library has been uploaded to the vault: http://tinyurl.com/qaf5f What's new (compared to the last "official" version, not the preview)? ====================================================================== - The interface, - the documentation, - the test-suite, - carefully picked and inline-documented source code examples, - the code generator for preprocessed files is entirely written on top of Wave, - the preprocessed files and the configuration (up to a certain extent) are compiler-agnostic, - the preprocessed files do not have to be regenerated for custom configurations, unless for optimization (and changing the library code, of course), and - the library is default calling convention-agnostic, OIW the default calling convention can be changed and detected without changing the library's configuration (unless for MSVC<8 due to the lack of a 'thiscall' keyword) Unless there are any objections from the review manager regarding the fitness of the submission, we can put the library back on the review schedule -- my apologies for it took so long, BTW. Regards, Tobias

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Boost-Install on Mac OS X
by Chris M 17 Sep '06

17 Sep '06

Hi I'm trying to build boost on Mac OS X 10.4.7. I had some Python issues and jam complained about Boost.Python so I downloaded and installed Python 2.4. Still though, that didn't fix it. I tried a half-hearted attempt at creating some symbolic links but decided there must be a "right" way to install boost on the latest mac OS X and was wondering if anyone here can point me toward a writeup of the process. Thanks, Chris

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Properties (newbie)
by Olivier Tournaire 17 Sep '06

17 Sep '06

I have already post this email, but I cannot see it on the list. So, I post it again ... Sorry ... Hi all, I am a new boost user (2 days old ...). I just want to know a few things. 1. I use an adjacency_list with my own properties to store my graph. I just want to know if it is possible to manipulate directly the properties' values. At the moment, I use get(...) to obtain the property, make my change, and use put(...) to set the new value. 2. My graph cannot contain parallel edges, so I use a setS. However, the documentation says that listS or vecS is more efficient in time and space complexity. Is it possible to use std::vector or std::list and to disallow parallele edges ? Thanks in advance Olivier --------------------------------- Découvrez un nouveau moyen de poser toutes vos questions quelque soit le sujet ! Yahoo! Questions/Réponses pour partager vos connaissances, vos opinions et vos expériences. Cliquez ici.

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Re: [Boost-users] [serialization] Purpose of load_construct_data (was: Re: Library Interface Design)
by JOAQUIN LOPEZ MU?Z 16 Sep '06

16 Sep '06

Hello again, lots of talking to each other today :) ----- Mensaje original ----- De: Robert Ramey <ramey(a)rrsd.com> Fecha: Sábado, Septiembre 16, 2006 8:03 pm Asunto: Re: [Boost-users] [serialization] Purpose of load_construct_data (was: Re: Library Interface Design) > JOAQUIN LOPEZ MU?Z wrote: [...] > > http://boost.org/libs/serialization/doc/ > > serialization.html#constructors > > where my_class serializes my_class::m *both* at > > my_class::serialize *and* my_class::(load|save)_construct_data. > > If the analysis I develop in my previous post is correct > > (is it?) this leads to my_class::m being serialized *twice* > > when a pointer to my_class is saved. Maybe it would sufice > > to rewrite this part of the documentation with a more > > sensible example like the one at test_non_default_ctor.cpp. > > What do you think? > > I agree. The fact that the example uses a member variable confuses > the issue. I'll amend the documentation accordingly. Thank you! > However, the current example does illustrate a case where it > seems impossible to avoid serializing a member twice. One > could leave it in the load_construct_data, and eliminate it from > the serialization code - but then this would work only if the > object was serialized via a pointer. If it were my program I would > say hmmmm - I'm really confusing the role of the variable m - If > its to be initialzed at construction - it shouldn't be messed with > by serialization or operator= etc. If its realy part of the objects > dynamic state - then it shouldn't be required at construction time. Well, I think the apparent puzzle stems from the incorrect assumption (IMHO) that a given member must be either part of the construction info or dynamic state --in many cases, it can be *both*, which is precisely what happens with my_class. I'd appreciate if you can consider this extension proposal that would allow for one-phase serialization while keeping the statu quo --maybe we can have our cake and eat it too :) Augment the serialization interface with a pair of new user-overridable function like this: template<typename Archive, class T> inline void construct_from_archive( Archive & ar, T * t, const unsigned int file_version) { // default implementation load_construct_data(ar,t,file_version); ar>>*t; } template<typename Archive, class T> inline void construct_to_archive( // OK, the name is ugly Archive & ar, const T * t, const unsigned int file_version) { // default implementation save_construct_data(ar,t,file_version); ar<<*t; } and use it when serializating T through a pointer. Now, if we return to the case of my_class, where my_class::m is both used at construction them and serialized as part of my_class::serialize, we can handle all situations as follows: // as in your example template<class Archive> inline void save_construct_data( Archive & ar, const my_class * t, const unsigned int) { ar << t->member; } // as in your example template<class Archive> inline void load_construct_data ( Archive & ar, my_class * t, const unsigned int) { int m; ar >> m; ::new(t)my_class(m); } // this is new template<class Archive> inline void construct_to_archive( Archive & ar, const my_class * t, const unsigned int fv) { save_construct_data(ar,t,fv); // avoid m being saved twice } // this is new template<class Archive> inline void construct_from_archive( Archive & ar, my_class * t, const unsigned int fv) { load_construct_data(ar,t,fv); // avoid m being loaded twice } My proposal basically amounts to adding a new customization point to the existing protocol for serialization of pointers. It has the following advantages: * You don't break anything (it's a pure extension). * It addresses a concern (one-phase serialization) that is conceptually different to the concerned addressed by (load|save)_construct_data (serializing non default- constructible objects), and does it so in an orthogonal manner. * It lets you solve the problem of members being both part of construction info and dynamic state, as I've (hopefully) just shown . How do you like this? > Anyway, I'll alter my example to make the variable in question > "const" and remove it from serialization which is a better > of example of the real cases where this can come up. > > Robert Ramey Best, Joaquín M López Muñoz Telefónica, Investigación y Desarrollo

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Re: [Boost-users] [serialization] serialization of pointers toprimitive types?
by JOAQUIN LOPEZ MU?Z 16 Sep '06

16 Sep '06

----- Mensaje original ----- De: Robert Ramey <ramey(a)rrsd.com> Fecha: Sábado, Septiembre 16, 2006 7:50 pm Asunto: Re: [Boost-users] [serialization] serialization of pointers toprimitive types? > JOAQUIN LOPEZ MU?Z wrote: [...] > > Wouldn't it be an option that pointers to > > primitive types will be handled as non-tracked? What would be > > the overhead of that option? In case this is an option, please > > consider my vote for inclusion as a new feature in Boost 1.35. > > OK - that would work fine - but I also believe it would trip the > infamous "const trap" so that might have to be considered. Umm... Well, at first blush, seems like serializating a pointer to a primitive type is no different than serializing a pointer to a non-primitive type --the same const issues, controversial as they might be, are already present. Besides, this new feature would be a pure extension, in the sense that code that didn't compile before would do now, so, you're positively not breaking anything. [...] > So - although the problem never comes up for me I concede your > point. I have erroneously confused the identity of two concepts - > serialization and tracking. From that standpoint I'm inclined > to make the change you suggest. The only concern is that it would > breakone of the user traps that inhibits certain user behavior > because it will almost surely lead to intractible problems. Again, I don't see how ensuring that the const rule works also for primitive types is any harder than the current implementation, which only applies to non-primitive type --seems like all you've got to do is to extend the enforcement in a straightforward manner. But then again, you're the implementor and surely can see internal difficulties I'm not aware of. > Dealing with the trap is a pain - but its much less painful than > dealing with user's who have done something that is permitted and > seems natural to do end up having archives that cannot be read or > recovered. I believe that serializing someting like > std::set<int *> will eventually lead to such problems eventually > in most cases. > > To summarize, you're correct. But I'm concerned that just > "fixing" the code will create new set of problems. Thanks for addressing my concern! Well, if you're doing the change for Boost 1.35 we'll surely have plenty of time to detect any potential problems that might arise. > Robert Ramey Best regards, Joaquín M López Muñoz Telefónica, Investigación y Desarrollo

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Re: [Boost-users] Comments / Advice on using Boost Test Library
by Sohail Somani 16 Sep '06

16 Sep '06

> -----Original Message----- > From: boost-users-bounces(a)lists.boost.org > [mailto:boost-users-bounces@lists.boost.org] On Behalf Of > Matt Schuckmann > > What I'd like to ask the Boost community about is this: how to go > > about unit testing private class methods. Hi, Rather than change the interface of my classes to use friend classes (I feel this unnecessarily clutters the interface), I do something simple and evil: #define private public #define protected public # include "MyClass.hpp" #undef private #undef protected Or something along those lines. This is permissable in unit tests, I would think. Sohail

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Re: [Boost-users] [serialization] serialization of pointers to primitive types?
by JOAQUIN LOPEZ MU?Z 16 Sep '06

16 Sep '06

Hello Robert, ----- Mensaje original ----- De: Robert Ramey <ramey(a)rrsd.com> Fecha: Sábado, Septiembre 16, 2006 8:01 am Asunto: Re: [Boost-users] [serialization] serialization of pointers to primitive types? > Serialization of pointers to primitive data types is prohibited. > I'm pretty sure this is mentioned in the documentation. ( don't > have the exact reference handy) I've persued the docs and in every place where this is referred to, the statement is that primitive types are not tracked, which is IMHO different than serialization of pointers to primitive types being forbidden. Examples: - Serializable concept: "A type T is Serializable if and only if one of the following is true: * it is a primitive type. [...] * it is a pointer to a Serializable type.[...]" from which it can be deduced that a pointer to a primitive type is serializable. - Object tracking: "Default tracking traits are: * For primitive, track_never.[...]" At the risk of repeating myself, I understand what serializing a pointer to a non-tracked type involves. This is not the same as not being able to serialize the pointer in the first place, which is what happens with primitive types, to my dismay. > - and it has been noted a couple of times. The reason is that > doing this would result in ALL usages of that type being tracked > - which is probably a heck of a lot more than the user had in mind. I'm not talking about primitive types being tracked, which I agree with you implies an unacceptable burden, but about the mere possibility of serialization of a pointer to a primitive type. Wouldn't it be an option that pointers to primitive types will be handled as non-tracked? What would be the overhead of that option? In case this is an option, please consider my vote for inclusion as a new feature in Boost 1.35. > > The way to serialize pointer to primitives > (serialization_level::prmitive) is to use BOOST_STRONG_TYPEDEF to > define a new type and specify serialization function for it. This > won't work for std::string so you'll have to make a trivial > derivation of std::string if you want to serialize a pointer to a > std::string. The problem with that is that it is an intrusive solution that complicates things when dealing with generic code. Sometimes, it can be just impossible to do that intrusive change or require the user to do it. From this restriction, for instance, we have that std::set<int*> is not serializable as is. Telling the user to change her definition to something like std::set<BOOST_STRONG_TYPEDEF(...)*> just for the sake of serializability could be unacceptable in some (many?) situations. > Robert Ramey Thank you, Joaquín M López Muñoz Telefónica, Investigación y Desarrollo

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Writing a more readable code
by Alexander Shyrokov 16 Sep '06

16 Sep '06

How can make the following code inside of for_each more readable? void f(char*); typedef std::map<int,char> TMap; TMap a; std::for_each(a.begin(),a.end(),boost::bind(f,boost::bind(&TMap::value_type::second,_1))); Is it possible to convert boost::bind(&TMap::value_type::second,_1) to a function object or a typedef name? -- Regards, Alexander. http://sjcomp.com

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Re: [Boost-users] [boost::serialization] Convert enumeration tostringand back again
by Nat Goodspeed 16 Sep '06

16 Sep '06

> ________________________________________ > From: boost-users-bounces(a)lists.boost.org [mailto:boost-users-bounces@lists.boost.org] On Behalf Of Robert Ramey > Sent: Saturday, September 16, 2006 2:27 AM > To: boost-users(a)lists.boost.org > Subject: Re: [Boost-users] [boost::serialization] Convert enumeration tostringand back again > > class param_choice { > enum > { > PARAM_CHOICE_UINT8, > PARAM_CHOICE_UINT16, > PARAM_CHOICE_UINT32, > PARAM_CHOICE_INT8, > PARAM_CHOICE_BOOL > } m_current_value; > template<class Archive> > save(Archive &ar, unsigned int version) { > std::string svalue; > switch(m_current_value){ [Nat] If I were going to do this "by hand," I'd at least want to construct a map. From that I'd populate another for the reverse lookup. But that's probably because I haven't yet read up on Boost.MultiIndex. > case PARAM_CHOICE_UINT8: > svalue = "PARAM_CHOICE_UINT8"; > ... > } > ar << BOOST_SERIALIZATION_NVP(svalue); > } > template<class Archive> > load(Archive &ar, unsigned int version){ > std::string svalue; > ar >> BOOST_SERIALIZATION_NVP(svalue); > if(svalue == std::string("PARAM_CHOICE_UINT8") > m_current_value = PARAM_CHOICE_UINT8; > else > if(... > ... > } > };

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Re: [Boost-users] Library Interface Design
by Nat Goodspeed 16 Sep '06

16 Sep '06

> -----Original Message----- > From: boost-users-bounces(a)lists.boost.org [mailto:boost-users- > bounces(a)lists.boost.org] On Behalf Of Scott Meyers > Sent: Tuesday, September 12, 2006 1:09 AM > To: boost-users(a)lists.boost.org > Subject: [Boost-users] Library Interface Design > > I've always been a big fan of the "don't let users create objects they > can't really use" philosophy. So, in general, I don't like the idea of > "empty" objects or two-phase construction. It's too easy for people to > make mistakes. [Nat] I try to design for single-phase construction myself. The aberrant use case that I've bumped into is deserialization. Intrusive serialization can preserve single-phase construction -- but what if the class designer didn't anticipate the need to serialize? I haven't yet worked with a serialization framework smart enough to consider constructor arguments. (I haven't yet worked with the Boost Serialization library, either; forgive me if this is already a solved problem.)

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Re: [Boost-users] Boost serialization : Possible to append to file?
by Robert Ramey 16 Sep '06

16 Sep '06

Daniel F. Savarese wrote: > In message <20060911172413.74527.qmail(a)web57207.mail.re3.yahoo.com>, > smith smit hson writes: >> This is regarding the boost serialization library. Is >> it possible to append to a pre-existing archive file? > > I don't think anyone's answered this yet. The answer is yes. Hmmm - that would surprise me. > > While on the topic of boost serialization, I'll add an unrelated note > that you cannot safely serialize objects from different threads when > using separate archive instances in each thread. Boost serialization > uses local static variables in places like > boost:archive::detail::oserializer::instantiate(), so even though > you're > using separate archive instances, there's only a single serializer for > a given archive type/object type pair. True - but this should be no problem since the the static object never changes. That is all the functions on this static object ar "const" so they should be re-entrant. Therefore, if you concurrently > serialize the same type of object with separate instances of the same > archive type, you can segfault. I don't see this. > The solution of course is to use > critical sections or delegate all serialization to a single thread. > But you wouldn't expect to have to do so when using separate > instances because the global behavior is not obvious to the API user. I don't think this should be necessary. If it is, then it is contraty to my intentation. Robert Ramey

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[boost::serialization] Convert enumeration to string and back again
by Graham Hudspith 16 Sep '06

16 Sep '06

Another "basic" question for the list again, apologies in advance. I have a class with a data member which is an enumeration, e.g.: typedef enum param_choice { PARAM_CHOICE_UINT8, PARAM_CHOICE_UINT16, PARAM_CHOICE_UINT32, PARAM_CHOICE_INT8, PARAM_CHOICE_BOOL } param_choice_e; I can quite happily user the Boost Serialization library to save and restore a class with a data member of this type: class Stuff { friend std::ostream& operator<<(std::ostream& os, const Stuff& stuff friend class boost::serialization::access; template<class Archive> void serialize(Archive& ar, const unsigned int file_version) { ar & BOOST_SERIALIZATION_NVP(choice); } param_choice choice; public: Stuff () {} Stuff (param_choice theChoice); }; This is using XML as the file-format. The data member appears in the file as an integer. However, what I would LIKE to do is output the value of "choice" as a string (e.g. instead of outputing <choice>2</choice>, the file contains <choice>UINT32</choice>). And do a conversion when I read it all back in again, of course. Can someone please provide some pointers to where I can find out how to do this? Or an example? Is the solution going to end up along the lines of: * Split the serialize into separate load and save routines * In the save, convert the data member into a string and output this to the archive * In the load, input from the archive into a string and then store this into the data member Best regards in anticipation, Graham.

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Boost serialization : Possible to append to file?
by smith smithson 16 Sep '06

16 Sep '06

Hello, This is regarding the boost serialization library. Is it possible to append to a pre-existing archive file? i.e. Create an archive file, serialize objects to it, close file, and then re-open file and append more serialized objects to it. Is this allowed? -Thanks! __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com

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unordered map base on how items are inserted.
by chun ping wang 16 Sep '06

16 Sep '06

I have a question on unordered_map. Are there are any boost library containers that acts like an associative array but also have the items base on how the order their inserted in. I.E. first item inserted is first one, second one is second. Thanks.

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program_options : Executing methods required for options_description before methods for command line options.
by Booster Booster 15 Sep '06

15 Sep '06

Hi, I have a list of options that I want to store before parsing the command line option. For example, po::options_description desc; // This has a couple of options. boost::program_options::variable_map options; po::store(po::command_line_parser(command_args).options(desc).run(), options); The problem is I want to execute the methods that correspond to 'desc' before the methods required by 'command_args' . Is there a way to populate the variable_map in a way such that I get the required sequence ? I did some reading of the docs, but couldn't find a way to do it. Any help would be appreciated. Thanks in advance, Sandy.

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calling a member function of a map iterator
by Alexander Shyrokov 15 Sep '06

15 Sep '06

I have a map<int,c*> and I would like to call a member function of the c* and provide a parameter to it. struct c{void f(char*){}}; typedef std::map<int,c*> TMap; TMap a; std::for_each(a.begin(),a.end(),boost::bind(&c::f,boost::bind(&TMap::value_type::second,_1)),NULL); I get "error C2091: function returns function" This is what I would like to replace with the for_each algorithm: for(TMap::iterator i=a.begin();i!=a.end();++i)(*i)->f(NULL); Thanks. -- Regards, Alexander. http://sjcomp.com

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Re: [Boost-users] Comments / Advice on using Boost Test Library
by Sohail Somani 15 Sep '06

15 Sep '06

> -----Original Message----- > From: boost-users-bounces(a)lists.boost.org > [mailto:boost-users-bounces@lists.boost.org] On Behalf Of Dave Steffen > > I just wonder: whats the big deal with breaking all the > encapsulation > > rules to do unit tests? > > Do you mean: > "why are people breaking encapsulation rules for unit tests?" > or > "why do people worry about breaking encapsulation rules > for unit tests?" Second one. I was worried for a second there that there was something I hadn't thought about :) Thanks.

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