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A question on switch_statement. Can any one with kindness help me?
by fmingu 05 Jul '09

05 Jul '09

I am using Dev-C++ with boost lambda expression, and I wrote the following lines: ................ int result,switchvalue; .............. (switch_statement(_1, case_statement<1> (var(result)=0), case_statement<2> (var(result)=1), case_statement<3> (var(result)=constant(value)), default_statement (var(std::cout)<<"wrong") ))(switchvalue); but the complier told me that: instantiated from `Arg::sig<boost::tuples::tuple<A&, B&, C&, Env&, boost::tuples::null_type, boost::tuples::null_type,.......... instantiated from `RET boost::lambda::lambda_functor_base<boost::lambda::switch_action<5, boost::lambda::detail::case_label<Case0>, .................... instantiated from `T::sig<boost::tuples::tuple<A&, boost::tuples::null_type, boost::tuples::null_type, ......... instantiated from here And I do not know where is wrong and how to correct it. By the way, can I use make_const(switchvalue) or constant(switchvalue) instead of switchvalue? Can any one with kindness help me?

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[Boost.Test] Error: Non-aligned pointer being freed
by Sebastian Hauer 05 Jul '09

05 Jul '09

Hello Boost Users, when running my unit tests on Mac OS X compiled with darwin gcc 4.2.1 for x86_64 I am getting the following error messages printed out even though no testing error were detected. As a side note running the same unit test on Windows MSVC 8 or Solaris gcc 3.2 succeeds without issues, so this seems to be either gcc 4.2 or Mac OS X specific. --------------- hauer@gandalf:~/dev/shark4/utils$ bin/darwin-4.2.1/debug/address-model-64/architecture-x86/shark-utilstest_d Running 51 test cases... *** No errors detected shark-utilstest_d(45498) malloc: *** error for object 0x3000100301fb0: Non-aligned pointer being freed (2) *** set a breakpoint in malloc_error_break to debug shark-utilstest_d(45498) malloc: *** error for object 0x30001003020c0: Non-aligned pointer being freed (2) *** set a breakpoint in malloc_error_break to debug shark-utilstest_d(45498) malloc: *** error for object 0x3000100302200: non-page-aligned, non-allocated pointer being freed *** set a breakpoint in malloc_error_break to debug --------------- I then ran the test through gdb and set a breakpoint at malloc_error_break and took a backtrace as shown below: ---------------- Starting program: /Users/hauer/dev/shark/utils/bin/darwin-4.2.1/debug/address-model-64/architecture-x86/shark-utilstest_d warning: posix_spawn failed, trying execvp, error: 86 Reading symbols for shared libraries ++++++.. done Breakpoint 1 at 0x7fff83745a51 Running 51 test cases... *** No errors detected pirate-utilstest_d(45520) malloc: *** error for object 0x3000100300630: Non-aligned pointer being freed (2) *** set a breakpoint in malloc_error_break to debug Breakpoint 1, 0x00007fff83745a51 in malloc_error_break () (gdb) bt #0 0x00007fff83745a51 in malloc_error_break () #1 0x00007fff83740ad0 in szone_error () #2 0x00000001001655f8 in boost::unit_test::framework_impl::clear (this=0x1001c7600) at impl/framework.ipp:133 #3 0x0000000100165728 in boost::unit_test::framework_impl::~framework_impl (this=0x1001c7600) at impl/framework.ipp:122 #4 0x0000000100160d82 in __tcf_1 () at impl/framework.ipp:222 #5 0x00007fff8369d3dc in __cxa_finalize () #6 0x00007fff8369d2f2 in exit () #7 0x0000000100000ceb in start () ------------------ This point to framework_impl's clean() method: ------------------ void clear() { while( !m_test_units.empty() ) { test_unit_store::value_type const& tu = *m_test_units.begin(); // the delete will erase this element from map if( test_id_2_unit_type( tu.second->p_id ) == tut_suite ) delete (test_suite const*)tu.second; else delete (test_case const*)tu.second; // <-- Line 133 } } ----------------- I think test_case's dtor was made public in 1.39 but I guess this did not fix the problem at hand. Regards, Sebastian

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Re: [Boost-users] A question on overloaded function? Can anyone with kindness help me?
by fmingu 05 Jul '09

05 Jul '09

I do not understand the sentence: Ignore the "conversion to unsigned int" part. As you know, I am a new comer and quite puzzled about that. Does that mean to change the complier enviroment? Can you give me an example? Thank you for your kindness. 在2009-07-02，"Steven Watanabe" <watanabesj(a)gmail.com> 写道： >AMDG > >fmingu wrote: >> But how can I change the expression to be legal and usable? >> bind(&std::pow,constant(-1),bind(&IIPrimemap::size,var(primemapvec))); >> I tried : >> bind(&std::pow,constant(-1.0),bind<int>(&IIPrimemap::size,var(primemapvec))); >> and >> bind(&std::pow,constant(-1.0),ret<int>(bind(&IIPrimemap::size,var(primemapvec)))); >> even >> bind(&std::pow,constant(-1.0),ll_dynamic_cast<int>(bind(&IIPrimemap::size,var(primemapvec)))); >> But the complier told me that: >> cannot resolve overloaded function `pow' based on conversion to >> type `unsigned int' >> > >Ignore the "conversion to unsigned int" part. The compiler >doesn't know how to handle std::pow and gets itself confused. >The problem is &std::pow, not the inner bind expression. > >> I do not know how to solve now. >> Can anyone with kindness help me? >> >> >>> You can't pass the address of an overloaded function to >>> a function template like bind without casting it to the >>> correct function pointer type. >>> > >In Christ, >Steven Watanabe > 200万种商品,最低价格,疯狂诱惑你

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CRC: Set checksum value
by Chris Spencer 04 Jul '09

04 Jul '09

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi all, I am using the CRC library in my program and need some way to set the value of the checksum. I.e., crc_32_type crc; crc.set_value(somevalue); crc.checksum() == somevalue; Is this possible short of modifying the source? I can't see any way to do it from the documentation. Cheers, Chris. -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.11 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iEYEARECAAYFAkpPuCsACgkQ6iqRtkAADZh4ZQCdGz9UWj9+9W/1SPw/jqPKCuyi /QAAniLRlVhIqhsAwAHYMFLlyOSuzdbY =ZLwZ -----END PGP SIGNATURE-----

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[test] gcc 4.2.1 unused warnings reappear in 1.39
by Sebastian Hauer 04 Jul '09

04 Jul '09

Hello Boost Users, I just upgraded from boost 1.38 to 1.39 on Mac OS X with darwin gcc 4.2.1 and noticed the following warnings: "g++" -ftemplate-depth-128 -O0 -fno-inline -Wall -g -dynamic -no-cpp-precomp -gdwarf-2 -arch x86_64 -fPIC -DBOOST_ALL_NO_LIB=1 -DBOOST_TEST_DYN_LINK -DSHARK_DEBUG -DSHARK_DYN_LINK -I"/Users/hauer/sys/boost_1_39-darwin-x86_64-xgcc42/include" -I"common/src" -I"utils/src" -c -o "utils/bin/darwin-4.2.1/debug/address-model-64/architecture-x86/test/shark/dtm/DateParserTest.o" "utils/test/shark/dtm/DateParserTest.cpp" /Users/hauer/sys/boost_1_39-darwin-x86_64-xgcc42/include/boost/test/floating_point_comparison.hpp:224: warning: ‘boost::test_tools::<unnamed>::check_is_close’ defined but not used /Users/hauer/sys/boost_1_39-darwin-x86_64-xgcc42/include/boost/test/floating_point_comparison.hpp:246: warning: ‘boost::test_tools::<unnamed>::check_is_small’ defined but not used Following the thread here: http://lists.boost.org/boost-users/2008/10/41326.php it seems that this was already something that got addressed a while ago and if I diff the header against 1.38 I notice this change for instance: namespace { -check_is_close_t const& check_is_close = unit_test::ut_detail::static_constant<check_is_close_t>::value; +check_is_close_t check_is_close; } Is there a reason why the static_constant template was removed and you reverted back to the original version? Regards, Sebastian PS: Below the original message from Gennadiy were he mentioned he applied the static_constant patch. On Fri, Nov 21, 2008 at 6:42 PM, Gennadiy Rozental<rogeeff(a)gmail.com> wrote: > Juergen Hunold <juergen.hunold <at> ivembh.de> writes: > >> On Wednesday 05 November 2008 19:20:37 Mat Marcus wrote: >> > On Mon, Oct 13, 2008 at 12:42 PM, Steven Watanabe <watanabesj <at> >> > gmail.com> >> > This trick seemed to work at first, but then when I ran the 1.37.0 >> > test tests I got: >> > >> > ..\..\libs\test\example\unit_test_example_10.cpp(75) : error C2039: >> > 'check_is_close' : is not a member of 'boost::test_tools' >> > ..\..\libs\test\example\unit_test_example_10.cpp(75) : error C2065: >> > 'check_is_close' : undeclared identifier >> >> Did you try my patch as described in #2390 ? > > I've checked in patch along the line of what you proposed. Let's see if > anything > breaks. > > Gennadiy > > _______________________________________________ > Boost-users mailing list > Boost-users(a)lists.boost.org > http://lists.boost.org/mailman/listinfo.cgi/boost-users >

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[utility] Anyone here using Intel 9.0 compiler + value_initialized?
by Niels Dekker - address until 2010-10-10 04 Jul '09

04 Jul '09

boost::value_initialized<T>, as included with the release version of Boost (current version: 1.39.0), has a conversion operator that breaks the principle of "logical constness": The member function itself is "const", but it returns a non-const reference to the data, T&. Four months ago, I fixed this issue on the development trunk [51355], replacing the conversion operator by a const and a non-const overload. The const overload returns a const reference to the data. (Ticket #2548.) After this fix, one specific version of a compiler yielded some compiler errors at the regression page: Intel 9.0 In fact it only yielded two compiler errors: only for implicitly conversions from value_initialized<NonPOD*>, and const value_initialized<NonPOD*>. Other conversions went well, for example, from const value_initialized<int> to const int&. Now I wonder, because Intel 9.0 is an old compiler version, and the regression failure occurs only in a very specific case, would it be acceptable to leave the fix in there, and have it shipped with an upcoming release version of Boost? Is anyone here likely to use the next version of Boost, including value_initialized<T>, on Intel 9.0? If so, would you find it acceptable to retrieve a reference to the data from value_initialized<T> by using the value_initialized::data() member function, or boost::get, instead of depending on implicit conversion? Note: Five days ago I committed a workaround for Intel 9.0 to the trunk [54502], removing the const-version of the overload. But it yielded many more Intel 9.0 errors (33!), as expected, on any attempt to convert a const value_initialized<T>. So does anyone here think this workaround is still useful? References: Ticket #2548, "Let's fix the logical constness of value_initialized!" https://svn.boost.org/trac/boost/ticket/2548 Utility/trunk regression page: www.boost.org/development/tests/trunk/developer/utility_.html [51355] Fix at the development trunk (4 months ago): https://svn.boost.org/trac/boost/changeset/51355 [54502] Intel 9.0 specific workaround (5 days ago): https://svn.boost.org/trac/boost/changeset/54502 Kind regards, -- Niels Dekker http://www.xs4all.nl/~nd/dekkerware Scientific programmer at LKEB, Leiden University Medical Center

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[Boost.Test] [1.38] Handling unexpected exceptions and system errors
by Greg Christopher 04 Jul '09

04 Jul '09

Hi, One of the things that sets boost apart from other frameworks is its ability to handle exceptions and report them. While I've used the BOOST_CHECK_THROW and BOOST_CHECK_EXCEPTION macros, I'd like a way to pass if an exception is thrown that we don't necessarily understand how to mention in the BOOST_CHECK_THROW or BOOST_CHECK_EXCEPTION macros. BOOST_CHECK_NO_THROW just makes sure no exception is thrown. In some ways it's an odd request to say "I expect some exception to be thrown that I do not care to specify", but that would work for us. In addition, it would be nice (and I bet it's already available) to be able to say "allow next test case to run in event of exception" or "allow next test suite to run In event of exception". Right now, all testing does seem to abort (none of the above macros are either present or coded in a way to match the system issue. Any tips on how to discover those values, or to go forward when some kind of exceptional condition is expected is appreciated. -Greg

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Query on implementing a lock manager
by dhruva 04 Jul '09

04 Jul '09

Hello, I am looking for a centralized or distributed lock manager. My needs are simple. I have names for each shared resource, I want to have advisory reader and writer locks on those named resources. I can implement it by having a server which serves all the lock requests. Each named lock will be a boost reader writer lock (which are implemented using atomic operations). Since lock requests come over TCPIP, the client (lock requester) will block till the server sends a response. Using non blocking sockets, the client can have a lock with time outs or async locks. If there is something similar available, I rather reuse than implement it from scratch. This requirement is to have some locking on files that intend to share using NFS and CIFS. Since NFS and CIFS servers are different, I will not get a common lock manager. I do not need sophisticated byte rane locking (fcntl), just a reader/writer lock on the file would do. Also, I ensure that the part of file path is unique and common across shares. This can be used as the resource name across the network. Any suggestions, ideas or links would be of real help. -dhruva Love Cricket? Check out live scores, photos, video highlights and more. Click here http://cricket.yahoo.com

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[Proto] Recreating an expression
by christophe henry 03 Jul '09

03 Jul '09

Thanks Eric for your fast answer! Unfortunately, this doesn't solve my problem. To make a very very long discussion long, here a small example showing the problem from another side: I have an expression wrapper called mp_terminal and I define terminals, but not in the documented way (which I suspect is the problem) but instead deriving from them (for convenience purposes), for example: struct True : mp_terminal<typename proto::terminal<guard_tag>::type> {...} These terminals are used with a simple grammar: struct BuildGuards : proto::or_< proto::when< proto::logical_or<BuildGuards,BuildGuards >, GuardOR<BuildGuards(proto::_left),BuildGuards(proto::_right)>() >, proto::when< proto::logical_and<BuildGuards,BuildGuards >, GuardAND<BuildGuards(proto::_left),BuildGuards(proto::_right)>() >, proto::when< proto::logical_not<BuildGuards >, GuardNOT<BuildGuards(proto::_value)>() >, proto::when < proto::terminal<guard_tag>, proto::_() > > {}; Then, expressions like: True()|| False() give the expected result (struct GuardOR<struct True,struct False>). Even True()&& (Dummy1() || !(False() || True())) give the expected result: struct GuardAND<struct True,struct GuardOR<struct Dummy1,struct GuardNOT<struct GuardOR<struct False,struct True> > > > But a "!" alone (meaning followed by just a terminal, not the other parts of the BuildGuards grammar) breaks all (as do all unary operators I tried), like !False() or True()|| !False(). !False() => struct GuardNOT<struct mp_terminal<struct boost::proto::exprns_::expr<struct boost::proto::tag::terminal,struct boost::proto::argsns_::term<struct guard_tag>,0> > > Notice that !(False() || True()) works! Now, if I do not derive from mp_terminal but instead proceed as documented, all works as expected: proto::terminal<True>::type True_; ... !False_ => correct result. Sadly, this documented usage is unpractical in my use case. So, supposing that I managed this easy grammar, I imagine that the usage I do of terminals (deriving from them) is not allowed. Then, why do most use cases work like a charm? Only unary operators seem to fail. Attached are 2 test files. V1 doesn't work in all cases while V2 does. I use 1.38. Thanks a lot! Christophe _________________________________________________________________ Windows Live™: Keep your life in sync. Check it out! http://windowslive.com/explore?ocid=TXT_TAGLM_WL_t1_allup_explore_012009

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detect if a type has a size_t member
by Hicham Mouline 03 Jul '09

03 Jul '09

Hello template <typename T> struct S { // how to detect T has a member static const size_t value ? // if T has value, define member of S, m1 of type T1, otherwise m2 of type T2 }; Regards,

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[Units][Interval] Using both together
by Anubis 03 Jul '09

03 Jul '09

Hello all! First let me congratule Matthias and Steven for the great units library. Just recently I have kicked out my own attempt at something like it and switched to boost::units. However I ran into trouble using both boost::units and boost::interval because a single int cannot be static casted to a quantity. So one could either provide a function like: static boost::units::quantity<Unit,Y> quantity(int aValue) { boost::units::quantity<Unit,Y>::from_value(aValue); } Probably not the best idea as any value would get casted to a quantity without notice, therefore totally ruining the concept of from_value. Or as I have implemented a specific checking policy for boost::interval: #include <boost/numeric/interval.hpp> //! The checking policy for boost::interval, if it uses boost::unit /*! Look into boost/numeric/interval/checking.hpp to see other possible base checking policies for template parameter Checking */ namespace boost { namespace units { namespace interval_support { template<class T, class Checking = boost::numeric::interval_lib::checking_base<T> > struct checking_base : Checking { static T empty_lower() { return (std::numeric_limits<T>::has_quiet_NaN ? std::numeric_limits<T>::quiet_NaN() : T::from_value(1)); } static T empty_upper() { return (std::numeric_limits<T>::has_quiet_NaN ? std::numeric_limits<T>::quiet_NaN() : T::from_value(0)); } }; }}} And actually use it like this: #include <boost/units/interval_support.hpp> // or whichever name typedef boost::numeric::interval_lib::change_checking< boost::numeric::interval<MY_QUANTITY_TYPE>, boost::units::interval_support::checking_base<MY_QUANTITY_TYPE> >::type my_unit_interval_type; HTH to easily use boost::units and boost::interval in the future, Thomas Taylor

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Re: [Boost-users] [smart_ptr] weak_ptr / shared_ptr interaction
by Alexander Heinrich 03 Jul '09

03 Jul '09

> Both s1 and s2 should now have use_count of 2 at this point, since there > are 2 shared_ptrs sharing ownership of the same pointee. > > The post-condition expression is correct; the value of r.use_count() > was changed by the construction of the new shared_ptr. Thanks for your reply. So you're saying that the behavior of shared_ptr is correct (perfectly fine with me). But then I have to say, that the documentation of shared_ptr located under http://www.boost.org/doc/libs/1_39_0/libs/smart_ptr/shared_ptr.htm#construc… is wrong, because it says that if you construct a shared_ptr from a weak_ptr (!) the use_count will *not* change.

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Problems with De/Serializing data structures with dll
by Grimm 03 Jul '09

03 Jul '09

Hi, I'm quite noob with boost and I wrote a little test program to test how boost handles serialization of data structures and deserializing the data in dll-plug-in. ( In this case only linked list of BaseImplementation objects, but if I got everything OK more complex structures is need to be serialized). It seems that I have(surprisingly) some problems with de/serializing list properly maybe cause of m_next pointers. I've read the documentation, but not have found help for this issue. Here's some relevant parts of my code ( I know It's a bit ugly, but hey! It's only for test purposes :) : Base.h: /* Abstract base class declaration of objects in linked list*/ #ifndef BASE_H #define BASE_H #include <string> #include <iostream> #include <boost/serialization/assume_abstract.hpp> class Base { public: Base(){} virtual ~Base(){} virtual void setID(const int a_id) =0; virtual const int getID() const =0; virtual void setValue( const double a_value ) =0; virtual const double getValue() const =0; virtual void setDescription( const std::string a_desc ) =0; virtual const std::string getDescription() const =0; virtual void setNext( Base* a_next ) =0; virtual Base* getNext() =0; //Operation - prints some information regarding the object virtual void print()const =0; private: friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, const unsigned int version) { } }; BOOST_SERIALIZATION_ASSUME_ABSTRACT(Base) #endif ###################################### BaseImplementation.h: //Implementation of Base-class (cells of linked list) #ifndef BASEIMPLEMENTATION_H #define BASEIMPLEMENTATION_H #include <boost/archive/text_oarchive.hpp> #include <boost/archive/text_iarchive.hpp> //#include <boost/serialization/export.hpp> #include <boost/serialization/base_object.hpp> #include <boost/serialization/utility.hpp> #include "Base.h" class BaseImplementation : public Base { public: //Constructor & Destructor BaseImplementation(); BaseImplementation( int a_id ); ~BaseImplementation(); //setter & getter virtual void setID( const int a_id ); virtual const int getID() const; virtual void setValue( const double a_value ); virtual const double getValue() const; virtual void setDescription( const std::string a_desc ); virtual const std::string getDescription() const; virtual void setNext( Base* a_next ); virtual Base* getNext(); //Operation - print virtual void print() const; private: friend class boost::serialization::access; template<class Archive> void serialize(Archive & ar, const unsigned int version) { ar & boost::serialization::base_object<Base>(*this); ar & m_id; ar & m_value; ar & m_desc; //THIS SEEMS TO BE THE PROBLEM!!! ar & m_next; } int m_id; double m_value; std::string m_desc; Base* m_next; }; //BOOST_CLASS_EXPORT_GUID(BaseImplementation, "base_impl") #endif ############################################### main program: // PluginTest.cpp : Defines the entry point for the console application. #include "stdafx.h" #include "PluginInterface.h" #include "BaseImplementation.h" #include <iostream> #include <fstream> #include <ctime> #include <cstdio> int _tmain(int argc, _TCHAR* argv[]) { std::remove("serialized.plop"); ...foo... ...foo.. ...foo.. //--Serialization-------------------------------------------------- std::ofstream ofs("serialized.plop"); boost::archive::text_oarchive oa(ofs); BaseImplementation* myObject = NULL; Base* first = NULL; BaseImplementation* prev = NULL; Base* tmp = NULL; //starting point of time consumption calc. start = clock(); //Let's create linked list of 114 instances of //BaseImplementation for dll to deserialize for(int i=0; i < 114; i++) { myObject = new BaseImplementation(); //sets the next cell of the list if(prev) { prev->setNext(myObject); } //first cell of linked list else { first = myObject; tmp =myObject; } //sets the data for object myObject->setID( i ); myObject->setValue( 0.5 +(double)i ); myObject->setDescription("This is object"); prev = myObject; } //The serialization itself oa.register_type(static_cast<BaseImplementation *>(tmp)); for(int i=0; i < 114; i++) { oa << tmp; tmp = tmp->getNext(); //oa << *tmp; } //oa << first; ofs.close(); //Deallocates created & serialized objects for(int i=0; i < 114; i++) { tmp = first->getNext(); delete first; first =tmp; } //stop time consumption calc. stop = clock(); //time consumption of serialization long serializationTime = ( stop - start ); //---Serializatio ends here----------------------------------------- //---Deserialization------------------------------------------------ //start the clock start = clock(); //Deserializes the linked list created above for dll-plugin thePlugin->load("serialized.plop"); //stop the clock stop = clock(); //time consumption of deserialization long deserializationTime = ( stop - start ); //Prinst some deserialized data thePlugin->print(50); std::cout <<"Serializations takes: " <<serializationTime <<" ms" <<std::endl; std::cout <<"Deserialization takes: " <<deserializationTime <<" ms" <<std::endl; ########################################################## Definition of thePlugin class: #include ".\cmyplugin.h" cMyPlugin::cMyPlugin() : cIHAPlugin() { m_name = "My plugin!"; m_description = "A plugin which is located in DLL!"; BaseImplementation* m_baseImpl = NULL; } cMyPlugin::~cMyPlugin() { } bool cMyPlugin::install(cIHAPluginCoreInterface* a_pluginCore) { std::cout << "installing plugin.. "; if( !a_pluginCore ) { std::cout << "failed!\n"; return false; } std::cout << "success.\n"; return true; } /*! \brief Gets the plugin name. \return The plugin name. */ const char* cMyPlugin::getName() { return m_name.c_str(); } /*! \brief Gets the plugin description. \return The plugin description. */ const char* cMyPlugin::getDescription() { return m_description.c_str(); } const int cMyPlugin::getNumber() { return m_baseImpl->getID(); } void cMyPlugin::load(std::string file) { //opens archive std::ifstream ifs(file.c_str()); boost::archive::text_iarchive ia(ifs); ia.register_type<BaseImplementation>(); //this doesn't handle pointers to next cell in list ia >> m_baseImpl; ifs.close(); } void cMyPlugin::print(int a_index) { m_first =m_baseImpl; Base* tmp =m_first; if( !m_first ) { std::cout << "ULTIMATE ERROR!!" << std::endl; return; } else { std::cout <<"--- This is value(double) of first cell: "; std::cout << m_first->getValue() <<" ---" <<std::endl; std::cout <<"--- This is value(double) of second cell: "; std::cout <<m_first->getNext()->getValue() <<" ---" <<std::endl; } for(int i=0; i < 114; i++ ) { if(i == a_index ) { tmp->print(); break; } tmp =tmp->getNext(); } } ################################################## Ok, this works still fine with 114 or less instances on the list, but when I try to do this with more than 114 instances it fails on line: oa << tmp; when it's called for first time. Error Message: "Unhandled exception at 0x1029dfdc (msvcr90d.dll) in SerializationTest.exe: 0xC00000FD: Stack overflow." I had to implement the deserialization in dll's load()-method cause it worked even worse with Serialize(...) used in documentation/examples I use Visual Studio 2008 and boost1.38 by the way. I "solved" this problem by not de/serializing the next pointer(for linked list) and constructed(set the next pointers) the list with own hands while deserializing. But thats possible only cause of simple structure of linked list and it will not work with more complex structures. Any ideas what I'm doing wrong in code I pasted above and how I get it work? And is serialization of tree-like data structures even possible with dlls involved? Thank you! ps: BOOST_CLASS_EXPORT_GUID() macro which is now commented away caused some weird linking errors. -- View this message in context: http://www.nabble.com/Problems-with-De-Serializing-data-structures-with-dll… Sent from the Boost - Users mailing list archive at Nabble.com.

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[smart_ptr] weak_ptr / shared_ptr interaction
by Alexander Heinrich 03 Jul '09

03 Jul '09

Hi @ boost-users. The documentation of shared_ptr states the following: <quote> template<class Y> explicit shared_ptr(weak_ptr<Y> const & r); Effects: Constructs a shared_ptr that shares ownership with r and stores a copy of the pointer stored in r. Postconditions: use_count() == r.use_count(). </quote> Now I experienced some odd behavior with the following piece of code: <code> boost::shared_ptr<int> s1(new int(42)); // use_count == 1 boost::weak_ptr<int> w(s1); // use_count == 1 boost::shared_ptr<int> s2(w); // use_count == 2 (expected use_count == 1) boost::shared_ptr<int> s3 = s2; // use_count == 3 (not sure what to expect here...) </code> 1) According to the documentation use_count should still be 1 after instantiating s2, but it is 2. Or did I misinterpret the docs? 2) Independent of whether instantiating s2 increments the use_count or not, I am unsure if assigning (or copying) a shared_ptr that was constructed from a weak_ptr should increment the use_count (see s3). I'd appreciate any comments on this. Best regards, Alexander

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[Spirit] chset_p
by Commander Pirx 03 Jul '09

03 Jul '09

Hi all, I've detected a strange behavior of Spirit using (VC9SP1). I assume that chset_p( "-_!#$%&*+|~" ) and chset_p( "!#$%&*+-_|~" ) are identical. I've only changed the order of the characters a little bit. But when i'm trying to parse a string like "abcd-edfg: " the parser eats the ':' sign but shouldn't. Examples here: token_ = alnum_p | chset_p( "-_!#$%&*+|~" ); // the line above works fine token_ = alnum_p | chset_p( "!#$%&*+-_|~" ); // here the ':' sign will be consumed! Thanx.

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[TypeTraits] is_base_of behavior
by Ioannis Papadopoulos 03 Jul '09

03 Jul '09

Hi, I'm getting different behaviours using is_base_of on different compilers (tested with gcc, icc, xlc). #include <boost/type_traits.hpp> #include <boost/static_assert.hpp> struct A { }; struct B : public A { }; int main() { // Compile fine under all compilers BOOST_STATIC_ASSERT( (boost::is_base_of<A,A>::value) ); // all fail in xlC 10.1, work fine in gcc 4.3-4.4 and icc 11 BOOST_STATIC_ASSERT( (boost::is_base_of<A,const A>::value) ); BOOST_STATIC_ASSERT( (boost::is_base_of<A,volatile A>::value) ); BOOST_STATIC_ASSERT( (boost::is_base_of<A,const volatile A>::value) ); // Compile fine under all compilers BOOST_STATIC_ASSERT( (boost::is_base_of<A,B>::value) ); BOOST_STATIC_ASSERT( (boost::is_base_of<A,const B>::value) ); BOOST_STATIC_ASSERT( (boost::is_base_of<A,volatile B>::value) ); BOOST_STATIC_ASSERT( (boost::is_base_of<A,const volatile B>::value) ); return 0; } Thanks

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One common mutex and lock to rule them all
by Ryan McConnehey 03 Jul '09

03 Jul '09

Are there plans to provide a command mutex and lock? I know there are versions in both the thread and interprocess library. I'm sure each library developed their own as the library was being created. I've seen users ask about different mutexes and lock before and usually they are directed to either of these libraries. It would seem, from a user perspective, that a more central location for mutexes and lock would be helpful. Possibly in it's own header library. Is there a plan to do this in the future? Ryan

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[Filesystem] API questions
by Alan M. Carroll 02 Jul '09

02 Jul '09

I am trying to use Boost.Filesystem and have run in to some issues with the API which may be actual problems or a lack of understanding on my part. 1) What is the generic way to create current directory and parent directory relative paths, e.g. "." and ".."? Currently for current directory I use boost::filesystem::path(boost::filesystem::path::string_type(1,boost::filesystem::slash<boost::filesystem::path>::value)) which is a bit verbose. Parent directory relative path is the same with '2' instead of '1'. Further, it presumes that string_type has a constructor taking a repeat count and a character which may not be true in all cases. I would define these functionally as path instances which, if passed to current_path, would stay in the same directory or move to the parent directory respectively. Is this usage too file system specific to be included in the library? Is there a superior way to create such paths? 2) Why isn't there a path constructor / generator which takes a pair of path element iterators? E.g. like path make_path(path::iterator x, path::iterator y) { path zret; for ( ; x != y ; ++x ) zret /= *x; return zret; } 3) I tried to write my own templated make_path but I don't see how to either use the path class as the template parameter or compute the path class from its iterator. That is, I want to use path::iterator x,y; // set somehow path p = make_path(x,y); Implemetation 1: template < typename Path > Path make_path(Path::iterator x, Path::iterator y) { ... } This fails because Path can not be deduced from the use of Path::iterator instances. Implementation 2: template < typename PathIter> ??? make_path(PathIter x, PathIter y) {...} I don't see how to specify the return type given the type of an iterator. I think it would be reasonable to put this in the iterator class typedef boost::BOOST_FILE_SYSTEM_NAMESPACE::basic_path<String, Traits> path_type; which would solve my problem. I was able to make it work with VC9 by adding this to the iterator definition in path.hpp typedef path_type path_type; // import from enclosing scope for clients but I don't know how portable that is. 4) My actual goal is to write the function path between(path here, path there) which returns a path such that after current_path(here); current_path(between(here,there)); this returns true equivalent(current_path(), there); and where the returned path is as relative as possible. This is very handy for file generation to generate # include "../inc/thing.h" instead of # include "C:/Documents and Settings/amc/view/main/inc/thing.h" If there is already an easy way to do that, I would be happy to be so informed. Thanks.

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Support of Pretty print
by Mario Chacon 02 Jul '09

02 Jul '09

Hello: Is is possible that boost have gdb pretty prints??.. It's works great with std objects, it will be awesome if boost have it too!! Salu2... masch...

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problems using serialization/export.hpp
by Andrew Michael Levin 02 Jul '09

02 Jul '09

I am having problems compiling the following file called save_a.cc. #include "save_a.hh" #include <string> #include <fstream> #include <boost/archive/text_oarchive.hpp> #include <boost/archive/text_iarchive.hpp> #include <boost/serialization/export.hpp> BOOST_IS_ABSTRACT(space::A) BOOST_CLASS_EXPORT(space::A) BOOST_CLASS_EXPORT(space::B) using namespace std; namespace space { void save(const A* _a, const string& _filename) { std::ofstream ofs(_filename.c_str()); OARCHIVE oa(ofs); oa & _a; ofs.close(); } } The errors that I get are as follows (I cut them off because they are a lot of them): [ 87%] Building CXX object src/shared/CMakeFiles/cryssmexlib.dir/test/save_a.o cd "/home/My Name/cryssmex/src/shared" && /usr/bin/c++.exe -Dcryssmexlib_EXPORTS -I/usr/include/boost-1_33_1 -I"/home/My Name/cryssmex/cryssmex/src/shared" -Wall -o CMakeFiles/cryssmexlib.dir/test/save_a.o -c "/home/My Name/cryssmex/cryssmex/src/shared/test/save_a.cc" /usr/include/boost-1_33_1/boost/serialization/export.hpp: In static member function `static void boost::archive::detail::guid_initializer<T>::export_register(const char*) [with T = space::A]': /usr/include/boost-1_33_1/boost/serialization/export.hpp:155: instantiated from `boost::archive::detail::guid_initializer<T>::guid_initializer(const char*) [with T = space::A]' /home/My Name/cryssmex/cryssmex/src/shared/test/save_a.cc:9: instantiated from here /usr/include/boost-1_33_1/boost/serialization/export.hpp:146: error: incomplete type `boost::serialization::extended_type_info_null<space::A>' used in nested name specifier /usr/include/boost-1_33_1/boost/serialization/export.hpp: In static member function `static void boost::archive::detail::guid_initializer<T>::export_register(const char*) [with T = space::B]': /usr/include/boost-1_33_1/boost/serialization/export.hpp:155: instantiated from `boost::archive::detail::guid_initializer<T>::guid_initializer(const char*) [with T = space::B]' /home/My Name/cryssmex/cryssmex/src/shared/test/save_a.cc:10: instantiated from here /usr/include/boost-1_33_1/boost/serialization/export.hpp:146: error: incomplete type `boost::serialization::extended_type_info_null<space::B>' used in nested name specifier /usr/include/boost-1_33_1/boost/archive/detail/oserializer.hpp: In static member function `static void boost::archive::detail::save_pointer_type<Archive, TPtr>::save(Archive&, const T&, const boost::archive::detail::basic_pointer_oserializer*) [with T = space::A, Archive = boost::archive::text_oarchive, TPtr = const space::A*]': /usr/include/boost-1_33_1/boost/archive/detail/oserializer.hpp:467: instantiated from `static void boost::archive::detail::save_pointer_type<Archive, TPtr>::invoke(Archive&, TPtr) [with Archive = boost::archive::text_oarchive, TPtr = const space::A*]' /usr/include/boost-1_33_1/boost/archive/detail/oserializer.hpp:536: instantiated from `void boost::archive::save(Archive&, const T&) [with Archive = boost::archive::text_oarchive, T = const space::A*]' /usr/include/boost-1_33_1/boost/archive/basic_text_oarchive.hpp:78: instantiated from `void boost::archive::basic_text_oarchive<Archive>::save_override(T&, int) [with T = const space::A* const, Archive = boost::archive::text_oarchive]' /usr/include/boost-1_33_1/boost/archive/detail/interface_oarchive.hpp:78: instantiated from `Archive& boost::archive::detail::interface_oarchive<Archive>::operator<<(T&) [with T = const space::A* const, Archive = boost::archive::text_oarchive]' /usr/include/boost-1_33_1/boost/archive/detail/interface_oarchive.hpp:86: instantiated from `Archive& boost::archive::detail::interface_oarchive<Archive>::operator&(T&) [with T = const space::A*, Archive = boost::archive::text_oarchive]' /home/My Name/cryssmex/cryssmex/src/shared/test/save_a.cc:18: instantiated from here /usr/include/boost-1_33_1/boost/archive/detail/oserializer.hpp:438: error: invalid use of undefined type `struct boost::serialization::extended_type_info_null<space::A>' /usr/include/boost-1_33_1/boost/serialization/type_info_implementation.hpp:26: error: declaration of `struct boost::serialization::extended_type_info_null<space::A>' /usr/include/boost-1_33_1/boost/archive/detail/oserializer.hpp:439: error: invalid use of undefined type `struct boost::serialization::extended_type_info_null<space::A>' /usr/include/boost-1_33_1/boost/serialization/type_info_implementation.hpp:26: error: declaration of `struct boost::serialization::extended_type_info_null<space::A>' /usr/include/boost-1_33_1/boost/archive/detail/oserializer.hpp:439: error: `save' is not a member of `<declaration error>' /usr/include/boost-1_33_1/boost/archive/detail/oserializer.hpp: In static member function `static const boost::archive::detail::basic_pointer_oserializer* boost::archive::detail::save_pointer_type<Archive, TPtr>::abstract<T>::register_type(Archive&) [with T = const space::A, Archive = boost::archive::text_oarchive, TPtr = const space::A*]': /usr/include/boost-1_33_1/boost/archive/detail/oserializer.hpp:360: instantiated from `static const boost::archive::detail::basic_pointer_oserializer* boost::archive::detail::save_pointer_type<Archive, TPtr>::register_type(Archive&, T&) [with T = const space::A, Archive = boost::archive::text_oarchive, TPtr = const space::A*]' /usr/include/boost-1_33_1/boost/archive/detail/oserializer.hpp:460: instantiated from `static void boost::archive::detail::save_pointer_type<Archive, TPtr>::invoke(Archive&, TPtr) [with Archive = boost::archive::text_oarchive, TPtr = const space::A*]' /usr/include/boost-1_33_1/boost/archive/detail/oserializer.hpp:536: instantiated from `void boost::archive::save(Archive&, const T&) [with Archive = boost::archive::text_oarchive, T = const space::A*]' /usr/include/boost-1_33_1/boost/archive/basic_text_oarchive.hpp:78: instantiated from `void boost::archive::basic_text_oarchive<Archive>::save_override(T&, int) [with T = const space::A* const, Archive = boost::archive::text_oarchive]' /usr/include/boost-1_33_1/boost/archive/detail/interface_oarchive.hpp:78: instantiated from `Archive& boost::archive::detail::interface_oarchive<Archive>::operator<<(T&) [with T = const space::A* const, Archive = boost::archive::text_oarchive]' /usr/include/boost-1_33_1/boost/archive/detail/interface_oarchive.hpp:86: instantiated from `Archive& boost::archive::detail::interface_oarchive<Archive>::operator&(T&) [with T = const space::A*, Archive = boost::archive::text_oarchive]' /home/My Name/cryssmex/cryssmex/src/shared/test/save_a.cc:18: instantiated from here ... ... Any idea what the problem is? Thanks.

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Confused about shared_mutex usage.
by Jason Cipriani 02 Jul '09

02 Jul '09

Hi all, I'm looking at the shared_mutex documentation here: http://www.boost.org/doc/libs/1_35_0/doc/html/thread/synchronization.html#t… But the documentation seems to be a little bit sparse and I'm having trouble figuring out how to use shared_mutex as a read/write lock. Just to make sure, lock_shared/unlock_shared is for the "readers", and lock/unlock is for the "writers"? If not, how do I lock/unlock it for reading, and how do I lock/unlock it for writing (exclusive lock)? Also I'm having trouble understanding what a "lock" is as opposed to a mutex. What is boost::shared_lock? Thanks! Jason

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Using mpl to instantiate template function
by Richard Hazlewood 02 Jul '09

02 Jul '09

Is there a type-only based way (e.g. with fold) of getting mpl to stamp out template functions for a collection of types? For example, this appears to work using mpl::for_each template <typename T> void Foo(); typedef mpl::vector<t1, t2, t3> Types; struct StampOut { template <typename T void operator()(const T *) const { Foo<T>(); } }; void dummy_() { mpl::for_each<Types>(Types, add_pointer<mpl::_1> >(StampOut()); } However, it requires the "dummy_" function to force instantiation. Is there an alternative trick?

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[interprocess] named_upgradable_mutex
by Moritz 02 Jul '09

02 Jul '09

Hi everybody, I have a question concerning the interprocess::updgradable::mutex. My scenario: I have a writer, which is manipulating an object in a interprocess::managed_shared_memory. And I have 'n' readers which are reading the object in the shared mem. If the writer is ready to write, it should get the possibility as fast as possible. So this is a variety of the classical readers/writers problem and I already found a good solution that fits my requirements. But this solution uses 3 mutexes and 1 counter so I am looking for a more efficient solution. The idea is that the writer locks the upgradable_mutex normally (calling lock()) and the readers lock it sharable (calling lock_sharable()). If the mutex is locked sharable and the writer tries to lock it normally, another attempt to lock it sharable has to wait until the writer succeeded in locking and unlocking the mutex. Is this correct proceeding? Thank you Moritz

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python context scope question
by Christopher Harvey 02 Jul '09

02 Jul '09

I'm running a bunch of python scripts from a directory, one after the other. I want to make sure that those scripts don't interfere with each other. My code looks like this: for(directory_iterator itr(filterDir);itr!=directory_iterator();++itr) { if(itr->path().extension()==".py") { try { object global = import("__main__").attr("__dict__"); object sys = import("sys"); sys.attr("path").attr("append")(str(filterDir)); exec_file(str(itr->path().string()), global, global); } catch(error_already_set const &) { cout<<"Python syntax/runtime error."<<endl; PyErr_Print(); } catch(...) { cout<<"Uknown error from script file: "<<itr->path()<<endl; } } } Basically what I want to know is this: For every iteration of the exterior for loop will any of the scripts that are executed be able to impact in any way another script that is executed? For example, I was thinking a script could remove that path that I want to add from the import search paths and break the next script that is run, since it wouldn't have that path. thanks.

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[Interprocess] [AIX 6.0] Abort and Segfault when calling destroy
by Thomas d'Erceville 01 Jul '09

01 Jul '09

Hello, Is there any support for boost on AIX 6.0? Because I got some trouble using boost::interprocess in this system. Actually, the rbtree_best_fit aborts (or Segfaults) when I try to destroy an object previsouly created by a construct. Here below a sample that aborts on AIX 6.0, compiled with boost 1.37: * managed_mapped_file mapfile(bi::create_only, address, size); Message * message = (mapfile.construct<Message>(bi::anonymous_instance))(); mapfile.destroy_ptr<Message>(message);* This abort message is : *Assertion failed :priv_is_allocated_block(block), file /..../boost/interprocess/mem_algo/rbtree_best_fit.hpp, line 1280* The full example is given by the linked file to this mail. I tried to replace the *rbtree_best_fit* by a *simple_seq_fit* but it doesn't change anything (except the abort message). Currently I can't use boost 1.38 or 1.39 because it can't compile it with xlc_r on AIX 6.0. So if someone has any option to solve this problem I take it! Best regards. Thomas d'Erceville

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