December 2007 - Boost-users - lists.preview.boost.org

[asio] how to specify a timeout?
by Arkadiy Vertleyb 03 Dec '07

03 Dec '07

Hi all, Is it possible in asio to supply a timeout for a read/write operation? Thanks, Arkadiy _________________________________________________________________ You keep typing, we keep giving. Download Messenger and join the i’m Initiative now. http://im.live.com/messenger/im/home/?source=TAGLM

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The Memory leak occurs with intrusive_ptr<T> and a class which containing wstring member variable.
by Youhei Murakami 03 Dec '07

03 Dec '07

Hello everyone. I had met a memory leak error runnnin program generated from a source which is attached to this mail. [flow] --The "sampleclass"-class has a wstring object as a member variable and a setter and a getter for this variable. --A sampleclass instance generated by the default new. --A pointer to sampleclass instance attached to intrusive_ptr<sampleclass>. --Make wstring instance with string L"0123456789abcdef". --The wstring instance set to a sampleclass instance using the sampleclass's setter. --Finish this program and a memory leak occurs. [emvironment] WindowsXP 64bit VisualStudio2005 sp1 boost-1_34_1 Unicode Charset #include "stdafx.h" #include <iostream> #include <boost/intrusive_ptr.hpp> #include <boost/detail/atomic_count.hpp> #include <boost/config.hpp> using namespace std; using namespace boost; #ifdef _DEBUG #define _CRTDBG_MAP_ALLOC #include <stdlib.h> #include <crtdbg.h> #define new ::new(_NORMAL_BLOCK, __FILE__, __LINE__) #endif namespace test { class countable { public: countable() : refcount(0) { } void add_ref( void ) { ++refcount; } void release( void ) { if( 0 == --refcount ) { delete this; } } int getcount() { return static_cast<long>(refcount); } private: boost::detail::atomic_count refcount; }; class sampleclass : public countable { wstring message; public: sampleclass(){} sampleclass( const wstring &mes ) : message(mes) {} void setmessage( const wstring &mes ) { message = mes; } wstring getmessage() { return message; } }; }; namespace boost { using namespace test; inline void intrusive_ptr_add_ref(countable *p) { p->add_ref(); } inline void intrusive_ptr_release(countable *p) { p->release(); } } int _tmain(int argc, _TCHAR* argv[]) { _CrtSetDbgFlag(_CRTDBG_ALLOC_MEM_DF|_CRTDBG_LEAK_CHECK_DF); using namespace test; { intrusive_ptr<sampleclass> intrusive_( new sampleclass(wstring(L"initial")) ); //---------- memory leak prone ------------------------// wstring mes( L"0123456789abcdef" ); intrusive_->setmessage( mes ); //---------- memory leak prone ------------------------// wcout << intrusive_->getmessage().c_str() << endl; } getchar(); return EXIT_SUCCESS; }

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[unordered] Remainder: Unordered review will start December 7
by Ion Gaztañaga 03 Dec '07

03 Dec '07

Hi to all, We have several reviews on December and just between two fast-track reviews, Unordered library will be reviewed December 7-16. For those interested in the library: *Description*: An implementation of the unordered containers specified in TR1, with most of the changes from the recent draft standards. *Author*: Daniel James *Download*: http://www.boost-consulting.com/vault/index.php?action=downloadfile&filenam… The documentation is in the zip file. Regards, Ion

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[boost-users][boost foreach, iterating]
by chun ping wang 03 Dec '07

03 Dec '07

hi, is their anyway where i can use boost foreach to iterate through two different containers at once. Like I have two vector of float and i want to iterate through them parallell.. (not using indexing.. since it doesn't work with all types). Thanks. Something that is equalivent to python, for x,y in xArray, yArray: # do some awesome stuff. print x, y

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Re: [Boost-users] [type_traits] checking if some type is copyconstructible or assignable
by Ovanes Markarian 03 Dec '07

03 Dec '07

I don't believe it as well, since I tried to implement it over the weekend, but I got always stuck, so I thought may be the boost gurus know how to do it ;) Thanks for your answer! Best Regards, Ovanes On 12/3/07, John Maddock <john(a)johnmaddock.co.uk> wrote: > > > > Ovanes Markarian wrote: > > >> Hello all! > > >> > > >> I am wondering, why the type_traits do not have a construct to check > > >> if some type is copy constructible (I mean if the copy constructor > > >> is available (public) or not). > > >> > > >> > > >> May be it can be implemented via calculating at compile time if some > > >> type can be copied or not... May be it is not possible at all. > > > > We don't believe that it's possible in the current language, sorry. Of > > course if you can prove us wrong..... > > > > Regards, John. <http://lists.boost.org/mailman/listinfo.cgi/boost-users> > >

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[type_traits] checking if some type is copy constructible or assignable
by Ovanes Markarian 03 Dec '07

03 Dec '07

Hello all! I am wondering, why the type_traits do not have a construct to check if some type is copy constructible (I mean if the copy constructor is available (public) or not). May be it can be implemented via calculating at compile time if some type can be copied or not... May be it is not possible at all. With Kind Regards, Ovanes

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build boost.python tutorial "hello world" without bjam
by damny＠web.de 03 Dec '07

03 Dec '07

hi there, for some days i try to build the boost.python tutorial "hello world" without bjam on winxp by using mingw. so i wrote a *.bat-file: // --- snip ----------------------------------------------------------------------------- @echo off SETLOCAL SET DIR_MINGW=c:\development_compiler\mingw\ SET DIR_BOOST=c:\development_compiler\_boost\ SET DIR_PYTHN=c:\development_compiler\python25\ SET DIR_PRJCT=%~dp0 SET NME_PRJCT=hello SET CC=c:\development_compiler\mingw\bin\g++.exe SET INCL=-I%DIR_BOOST%include\boost-1_34_1 -I%DIR_PYTHN%include -I%DIR_MINGW%include SET LIBS=-L%DIR_BOOST%lib -L%DIR_PYTHN%libs -L%DIR_MINGW%lib %CC% -O0 -shared %INCL% %LIBS% -lboost_python-mgw34-s-1_34_1 -lpython25 %DIR_PRJCT%%NME_PRJCT%.cpp -o %NME_PRJCT%.pyd ENDLOCAL // --- snip ----------------------------------------------------------------------------- this works fine. but nevertheless it produces errors. // --- snip ----------------------------------------------------------------------------- D:\Temp\boost_test>c:\development_compiler\mingw\bin\g++.exe -O0 - shared -Ic:\development_compiler\_boost\include\boost-1_34_1 -Ic:\development_compiler\python25\include -Ic:\development_compiler\mingw\include -Lc:\development_compiler\_boost\lib -Lc:\development_compiler\python25\libs -Lc:\development_compiler\mingw\lib -lboost_python-mgw34-mt-s-1_34_1 -lpython25 D:\Temp\boost_test\hello.cpp -o hello.pyd C:\DOKUME~1\DBlock\LOKALE~1\Temp/cciAbaaa.o:hello.cpp:(.text+0x11e): undefined reference to `_imp___ZN5boost6python6detail11init_moduleEPKcPFvvE' C:\DOKUME~1\DBlock\LOKALE~1\Temp/cciAbaaa.o:hello.cpp:(.text$_ZN5boost6python3de fIPFPKcvEEEvS3_T_[void boost::python::def<char const* (*)()>(char const*, char const* (*)())]+0x6e): undefined reference to `_imp___ZN5boost6python6detail17scope_setattr_docEPKcRKNS0_3api6objectES3_' C:\DOKUME~1\DBlock\LOKALE~1\Temp/cciAbaaa.o:hello.cpp:(.text$_ZN5boost6python6detail17make_function_auxIPFPKcvENS0_21default_call_policiesENS_3mpl7vector1IS4_EE EENS0_3api6objectET_RKT0_RKT1_[boost::python::api::objectboost::python::detail: :make_function_aux<char const* (*)(), boost::python::default_call_policies, boost::mpl::vector1<char const*> >(char const* (*)(), boost::python::default_call_policies const&, boost::mpl::vector1<char const*> const&)]+0x73): undefined refere nce to `_imp___ZN5boost6python7objects15function_objectERKNS1_11py_functionE' C:\DOKUME~1\DBlock\LOKALE~1\Temp/cciAbaaa.o:hello.cpp:(.text$_ZN5boost6python7objects21py_function_impl_baseC2Ev[boost::python::objects::py_function_impl_base:: py_function_impl_base()]+0x7): undefined reference to `_imp___ZTVN5boost6python7objects21py_function_impl_baseE' C:\DOKUME~1\DBlock\LOKALE~1\Temp/cciAbaaa.o:hello.cpp:(.rdata$_ZTVN5boost6python7objects23caller_py_function_implINS0_6detail6callerIPFPKcvENS0_21default_call_p oliciesENS_3mpl7vector1IS6_EEEEEE[vtable for boost::python::objects::caller_py_function_impl<boost::python::detail::caller<char const* (*)(), boost::python::def ault_call_policies, boost::mpl::vector1<char const*> > >]+0x18): undefined reference to 'boost::python::objects::py_function_impl_base::max_arity() const' C:\DOKUME~1\DBlock\LOKALE~1\Temp/cciAbaaa.o:hello.cpp:(.text$_ZN5boost6python3api6objectC2Ev[boost::python::api::object::object()]+0x7): undefined reference to `_imp___Py_NoneStruct' C:\DOKUME~1\DBlock\LOKALE~1\Temp/cciAbaaa.o:hello.cpp:(.text$_ZN5boost6python7objects23caller_py_function_implINS0_6detail6callerIPFPKcvENS0_21default_call_poli ciesENS_3mpl7vector1IS6_EEEEED1Ev[boost::python::objects::caller_py_function_impl<boost::python::detail::caller<char const* (*)(), boost::python::default_call_policies, boost::mpl::vector1<char const*> > >::~caller_py_function_impl()]+0x16) : undefined reference to `_imp___ZN5boost6python7objects21py_function_impl_baseD2Ev' C:\DOKUME~1\DBlock\LOKALE~1\Temp/cciAbaaa.o:hello.cpp:(.text$_ZN5boost6python7objects23caller_py_function_implINS0_6detail6callerIPFPKcvENS0_21default_call_poli ciesENS_3mpl7vector1IS6_EEEEED0Ev[boost::python::objects::caller_py_function_impl<boost::python::detail::caller<char const* (*)(), boost::python::default_call_policies, boost::mpl::vector1<char const*> > >::~caller_py_function_impl()]+0x16) : undefined reference to `_imp___ZN5boost6python7objects21py_function_impl_baseD2Ev' C:\DOKUME~1\DBlock\LOKALE~1\Temp/cciAbaaa.o:hello.cpp:(.text$_ZNK5boost6python15to_python_valueIRKPKcEclES5_[boost::python::to_python_value<char const* const&>::operator()(char const* const&) const]+0xf): undefined reference to `_imp___ZN5boost6python9converter19do_return_to_pythonEPKc' C:\DOKUME~1\DBlock\LOKALE~1\Temp/cciAbaaa.o:hello.cpp:(.text$_ZNK5boost6python9type_info4nameEv[boost::python::type_info::name() const]+0x15): undefined reference to `_imp___ZN5boost6python6detail12gcc_demangleEPKc' collect2: ld returned 1 exit status // --- snip ----------------------------------------------------------------------------- any ideas what's wrong? any ideas how to fix that? many, many thnx daniel PS: i build boost.python by doing this ... // --- snip ----------------------------------------------------------------------------- @echo off SETLOCAL SET path=%path%;C:\Development_Compiler\MinGW\Bin bjam.exe -a "-sTOOLS=mingw" "-sGCC_ROOT_DIRECTORY=C:\Development_Compiler\MinGW" "-sPYTHON_VERSION=2.5" "-sPYTHON_ROOT=C:\Development_Compiler\Python25" --build-dir=C:\Temp --toolset=gcc --with-python install ENDLOCAL // --- snip ----------------------------------------------------------------------------- _____________________________________________________________________ Der WEB.DE SmartSurfer hilft bis zu 70% Ihrer Onlinekosten zu sparen! http://smartsurfer.web.de/?mc=100071&distributionid=000000000066

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Simple Linking Error
by Daniel 03 Dec '07

03 Dec '07

I wrote a simple "Hello, world!" program to test if boost/asio was working correctly: #include <iostream> #include <boost/date_time/posix_time/posix_time.hpp> int main() { std::cout << "Hello, world!\n"; return 0; } But, I get this: (GCC C++ 4.1.2/Linux version 2.6.22-gentoo-r8) test.cpp:(.text+0x10b): undefined reference to `boost::system::get_system_category()' test.cpp:(.text+0x115): undefined reference to `boost::system::get_posix_category()' test.cpp:(.text+0x11f): undefined reference to `boost::system::get_posix_category()' test.cpp:(.text+0x129): undefined reference to `boost::system::get_system_category()' This happens when I used '#include <boost/date_time/posix_time/posix_time.hpp>' I can't figure out what I'm missing

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serialization of vector of pointers
by Stathis 03 Dec '07

03 Dec '07

Hi, What is the right way to serialize/deserialize a container of pointers, e.g. std::vector< int* > ? I want to store the values, not the addresses in this case. Should I just flatten my data and store it in a different fashion, then read the flat data and build my objects with a builder? I ended up storing the size of the container in a separate variable before the data, when serializing. Then when deserializing, I use this size value to scale the container, create new ints, read their individual values via the deserialized data values and finally store them back to the new object. Can you give an example of how to do this better? cheers, --stathis

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[serialization] Can binary-objects be trackable ?
by Youhei Murakami 03 Dec '07

03 Dec '07

Hello everyone. I found a description pasted below in boost/serialization/binary_object.hpp. Does this description means that binary-objects can't track ? [ in binary_object.hpp ] // don't track binary objects - usually they will be created on the stack // and tracking algorithm (which uses the object address) might get // confused. note that these address will likely be members of some // other structure which itself is tracked, so as a practical matter // suppressing tracking shouldn't cause any redundancy. BOOST_CLASS_TRACKING(binary_object, boost::serialization::track_never) #endif // BOOST_SERIALIZATION_BINARY_OBJECT_HPP

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