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

Re: [Boost-users] [Serialization] good practice for serialization with private default constructors
by David Rajaratnam 04 Apr '14

04 Apr '14

On 05/04/14 03:46, Robert Ramey wrote: > > Note that subject is treated in the manual. I forget where. You'll > have to > look for it. boost/libs/serialization/doc/index.html > > And there are two tests which explicitly test this. see. > > https://github.com/boostorg/serialization/blob/develop/test/test_non_defaul… > Sorry, I couldn't find the reference in the manual addressing private default constructor good/bad practice. I am undoubtedly misunderstanding something, but I'm not sure the part on non-default constructors is relevant. In any case... > > never do ar & *x. This will evade certain code which the library > requires. Trust > the source luke! > this answers my question. Regards, Dave PS. Thanks for the great library!

1 0

[Serialization] Polymorphic portable binary archive error
by Szymon Gatner 04 Apr '14

04 Apr '14

Hi, I am trying to use polymorphic_portable_binary_archive in Visual Studio 2012 but adding relevant *.cpp(s) (from examples directory) to the project yields: 1>c:\users\bravo\documents\visual studio 2012\projects\polymorphic_serialization_test\polymorphic_portable_binary_oarchive.hpp(19): fatal error C1083: Cannot open include file: 'boost/archive/detail/polymorphic_oarchive_dispatch.hpp': No such file or directory 1>c:\users\bravo\documents\visual studio 2012\projects\polymorphic_serialization_test\polymorphic_portable_binary_oarchive.cpp(18): fatal error C1083: Cannot open include file: 'boost/archive/impl/archive_pointer_oserializer.ipp': No such file or directory Error 2 error C1083: Cannot open include file: 'boost/archive/detail/polymorphic_iarchive_dispatch.hpp': No such file or directory c:\users\bravo\documents\visual studio 2012\projects\polymorphic_serialization_test\polymorphic_portable_binary_iarchive.hpp 19 polymorphic_serialization_test Indeed, none of those files exists in my boost release, I am using boot 1.54. Also: what is the status of Portable Binary Archives? From forum posts It would seem that ony unsupported things is floating point numbers? Is that correct? Other that that, is everything else production ready? Regards, Szymon Gatner -- Szymon Gatner Bravasoft / The Lordz Games Studio Twitter: @sgatner

1 0

boost::regex_replace problem
by Илья 04 Apr '14

04 Apr '14

Greetings everyone! My name is Ilya and i have such problem with boost::regex_replace : I want to process some text messages to find and replace with * swears there. I wrote regular expressions, this is an example of one of them: "([[:punct:]]|[[:space:]]|[[:digit:]]|^)(?:a)(?:[[:punct:]]|[[:space:]]|[[:digit:]])*(?:b)(?:[[:punct:]]|[[:space:]]|[[:digit:]])*(?:c)([[:punct:]]|[[:space:]]|[[:digit:]]|$)". The format string i used is: "$1***$2" Then i run boost::regex_replace() and it works almoust correctly, except one case: when i have message with abc's standing next to each other with one separator beetween them, like this: "abc abc", "--abc-abc--" etc. So i need to run boost::regex_replace() twice to process corectly such messages. Are there any other ways to solve this problem? Thank you for answers. Ilya Bindiug

2 2

[Serialization] good practice for serialization with private default constructors
by David Rajaratnam 04 Apr '14

04 Apr '14

I am interested to know what is good practice when dealing with serializable classes with private default constructors. In particular it is not clear what is the cleanest way to deserializing these objects. Explaining with reference to the example from: http://stackoverflow.com/questions/7123613/boost-serialization-does-the-def… The answer to this stackoverflow question shows how to serialize/deserialize an object with a private default constructor. Summarizing: class Colour { friend class boost::serialization::access; // private default constructor // template serialize function public: boost::shared_ptr<Colour> test() { // returns new object; } }; int main(){ boost::shared_ptr<Colour> c = Colour::test(); std::stringstream str; boost::archive::text_oarchive oa(str); oa & c; // ... c.reset(); boost::archive::text_iarchive ia(str); ia & c; } However, it is important to observe that it is not just serializing/deserializing the object itself but also the shared pointer to the object! So for example: replacing "ao & c;" with "oa & *c;" will compile and properly serialize (only) the object, but will throw an exception when it tries to deserialize because it is expecting a shared pointer to the object. My solution to this is to provide a constructor that takes an archive object: class Colour { // other stuff public: template<typename Archive> Colour(Archive& ar) { ar >> *this; } }; // some explicit specializations where there are // other single argument constructors The example main then becomes: int main(){ boost::shared_ptr<Colour> c = Colour::test(); std::stringstream str; boost::archive::text_oarchive oa(str); oa & *c; // ... boost::archive::text_iarchive ia(str); Colour c2(ia); } The above works and is clean in that only the Colour object is being serialized/deserialized. However, I'm not sure if it is good practice. In particular: - I presume there will be an intermediate copy of the Colour object being created by the archive object. - Passing *this to a function that takes an object of type Object from within the constructor seems like a bad thing. - In general template based constructors seems like they should be avoided. So, my question is whether my solution is reasonable or is there a better option. Regards, Dave R.

1 0

[wave] fail to parse variadics macro
by gag maker 03 Apr '14

03 Apr '14

Hi, I'm using wave library from boost 1.53.0. Library compiled with default settings, meaning BOOST_WAVE_SUPPORT_VARIADICS_PLACEMARKERS is set to 1 in wave_config.cpp Wave driver is also compiled to support variadics. However, when I try to feed translation unit to wave driver it reports following error: .../compiler.h:32:1: error: ill formed preprocessor directive: #define __builtin_warning(x, y...) (1) And btw, wave driver was called with --variadics option What went wrong here? Thank you, --Alex

6 9

[preprocessor] Undeclared identifier BOOST_PP_IIF_0 under Clang only
by Pierre Talbot 03 Apr '14

03 Apr '14

Hi, I defined a macro using Boost.Preprocessor that compiles and works fine under gcc but fails to compile under Clang. The macro is defined here: https://github.com/ptal/Boost.Expected/blob/master/include/boost/functional… And the error message follows this message, the file using the macro is https://github.com/ptal/Boost.Expected/blob/master/example/monadic_calculat… Thanks for any helps, Pierre Talbot Boost.Expected/example/monadic_calculator$ b2 ...patience... ...found 1246 targets... ...updating 2 targets... clang-linux.compile.c++.without-pth bin/clang-linux-3.5.0/debug/monadic_calculator.o monadic_calculator.cpp:141:15: error: use of undeclared identifier 'BOOST_PP_IIF_0' etokens = DO( ^ ../../include/boost/functional/do_yield.hpp:100:17: note: expanded from macro 'DO' #define DO(...) DO_SEQ(BOOST_PP_VARIADIC_TO_SEQ(__VA_ARGS__)) ^ ../../include/boost/functional/do_yield.hpp:97:3: note: expanded from macro 'DO_SEQ' BOOST_PP_SEQ_FOR_EACH_I(DO_ELEM, seq, seq) \ ^ /usr/local/boost_1_55_0/boost/preprocessor/seq/for_each_i.hpp:27:55: note: expanded from macro 'BOOST_PP_SEQ_FOR_EACH_I' # define BOOST_PP_SEQ_FOR_EACH_I(macro, data, seq) BOOST_PP_FOR((macro, data, seq (nil), 0), BOOST_PP_SEQ_FOR_EACH_I_P, BOOST_PP_SEQ_FOR_EACH_I_O, BOOST_PP_SEQ_FOR_EACH_I_M) ^ /usr/local/boost_1_55_0/boost/preprocessor/repetition/for.hpp:27:23: note: expanded from macro 'BOOST_PP_FOR' # define BOOST_PP_FOR BOOST_PP_CAT(BOOST_PP_FOR_, BOOST_PP_AUTO_REC(BOOST_PP_FOR_P, 256)) ^ /usr/local/boost_1_55_0/boost/preprocessor/cat.hpp:22:32: note: expanded from macro 'BOOST_PP_CAT' # define BOOST_PP_CAT(a, b) BOOST_PP_CAT_I(a, b) ^ /usr/local/boost_1_55_0/boost/preprocessor/cat.hpp:29:34: note: expanded from macro 'BOOST_PP_CAT_I' # define BOOST_PP_CAT_I(a, b) a ## b ^ <scratch space>:130:1: note: expanded from here BOOST_PP_FOR_1 ^ /usr/local/boost_1_55_0/boost/preprocessor/repetition/detail/for.hpp:22:37: note: expanded from macro 'BOOST_PP_FOR_1' # define BOOST_PP_FOR_1(s, p, o, m) BOOST_PP_FOR_1_C(BOOST_PP_BOOL(p(2, s)), s, p, o, m) ^ /usr/local/boost_1_55_0/boost/preprocessor/repetition/detail/for.hpp:279:42: note: expanded from macro 'BOOST_PP_FOR_1_C' # define BOOST_PP_FOR_1_C(c, s, p, o, m) BOOST_PP_IIF(c, m, BOOST_PP_TUPLE_EAT_2)(2, s) BOOST_PP_IIF(c, BOOST_PP_FOR_2, BOOST_PP_TUPLE_EAT_4)(BOOST_PP_EXPR_IIF(c, o)(2, s), p, o, m) ^ /usr/local/boost_1_55_0/boost/preprocessor/control/iif.hpp:18:37: note: expanded from macro 'BOOST_PP_IIF' # define BOOST_PP_IIF(bit, t, f) BOOST_PP_IIF_I(bit, t, f) ^ /usr/local/boost_1_55_0/boost/preprocessor/control/iif.hpp:25:39: note: expanded from macro 'BOOST_PP_IIF_I' # define BOOST_PP_IIF_I(bit, t, f) BOOST_PP_IIF_ ## bit(t, f) ^ <scratch space>:136:1: note: expanded from here BOOST_PP_IIF_0 ^

2 4

problems with nested boost::bind and boost::asio
by Marco 03 Apr '14

03 Apr '14

Hi, I use async_read of boost::asio to receive network data. After a complete 'packet' was read (which needs 2 async read calls) I want to call a user defined handler. Therefore, I introduced a new templater parameter in my callback methods. Unfortunately, my code ends in a compile error. If I outcomment the handler call, than it compiles fine. But with the call of the handler object, I got a conversion error. At first I want to describe my code on some excerpts: ---------------------------------------------------------------------------------------- In 'startProcessing' I use perfect forwarding for the callback object. template<typename T> void startProcessing(T&& handler,bool activateNoDelay = true) { // m_socket.set_option(asio::ip::tcp::no_delay(activateNoDelay )); // startAsyncRead(std::forward<T>(handler)); } ---------------------------------------------------------------------------------------- 'startAsynRead' has two overloads. One for boost::bind objects and one for all other. The boost bind objects are encased with boost::protect to prevent an evaluation of boost::bind in the later binds. // template<typename T> void startAsyncRead(T handler) { startAsyncReadImpl(handler); } //overload for boost bind objects necessary template<typename R, typename F, typename L> void startAsyncRead(boost::_bi::bind_t<R, F, L> handler) { startAsyncReadImpl(boost::protect(handler)); } ---------------------------------------------------------------------------------------- 'startAsyncReadImpl' calls asio::async_read and uses boost::bind to commit the handler object as a third parameter. // template<typename T> void startAsyncReadImpl(T&& handler) { //at first we need to read the header information auto& buf = m_headerInBuffer.getBuffer(); boost::asio::async_read( m_socket, boost::asio::buffer(buf.begin(), buf.size()), boost::asio::transfer_exactly(buf.size()), boost::bind(&CMessageChannel::handleAsyncReadHeader<T>, this,_1, _2, std::forward<T>(handler)) ); } ---------------------------------------------------------------------------------------- 'handleAsyncReadHeader' does some stuff and than calls asio::async_read with another method. // template<typename T> void handleAsyncReadHeader(const boost::system::error_code& error, std::size_t bytes_transferred, T handler) { . . . boost::asio::async_read( m_socket, boost::asio::buffer(buf.begin(), buf.size()), boost::asio::transfer_exactly(size), boost::bind(&CMessageChannel::handleAsyncReadBody<T>, this, _1, _2,handler) ); } ---------------------------------------------------------------------------------------- Finally, 'handleAsyncReadBody' has to do the wished call of the handler. // template<typename T> inline void CMessageChannel::handleAsyncReadBody(const boost::system::error_code& error, std::size_t bytes_transferred, T handler) { ... handler(Packet(m_headerInBuffer.getShort(4), bytes_transferred, m_currReadBuffer)); } ---------------------------------------------------------------------------------------- And here a call of start process: void testPacket(Packet& packet) {} . . . conn->startProcessing(boost::bind(&CMessageServer::testPacket, this, _1)); ---------------------------------------------------------------------------------------- I use Visual Studio 2013 and got the following error message: 1>D:\libraries\cpp\boost\boost_1_55_0\boost/bind/bind.hpp(313): error C2664: 'void boost::_mfi::mf1<void,tuc::nw::CMessageServer,tuc::nw::Packet &>::operator ()(T *,A1) const' : Konvertierung von Argument 2 von 'const tuc::nw::Packet' in 'tuc::nw::Packet &' nicht möglich -> can't convert argument 2 'const tuc::nw::Packet' to tuc::nw::Packet & I never use const in my call chain. It seems that boost::protect introduces the const for the parameter. And I have no idea how to fix it :( ---------------------------------------------------------------------------------------- Here is the complete error message: 1>------ Erstellen gestartet: Projekt: network, Konfiguration: Release Win32 ------ 1> MessageChannel.cpp 1> MessageServer.cpp 1>D:\libraries\cpp\boost\boost_1_55_0\boost/bind/bind.hpp(313): error C2664: 'void boost::_mfi::mf1<void,tuc::nw::CMessageServer,tuc::nw::Packet &>::operator ()(T *,A1) const' : Konvertierung von Argument 2 von 'const tuc::nw::Packet' in 'tuc::nw::Packet &' nicht möglich 1> with 1> [ 1> T=tuc::nw::CMessageServer 1> , A1=tuc::nw::Packet & 1> ] 1> Durch die Konvertierung gehen Qualifizierer verloren 1> D:\libraries\cpp\boost\boost_1_55_0\boost/bind/bind_template.hpp(47): Siehe Verweis auf die Instanziierung der gerade kompilierten Funktions-template "void boost::_bi::list2<boost::_bi::value<T>,boost::arg<1>>::operator ()<F,boost::_bi::list1<const A1 &>>(boost::_bi::type<void>,F &,A &,int)". 1> with 1> [ 1> T=tuc::nw::CMessageServer * 1> , F=boost::_mfi::mf1<void,tuc::nw::CMessageServer,tuc::nw::Packet &> 1> , A1=tuc::nw::Packet 1> , A=boost::_bi::list1<const tuc::nw::Packet &> 1> ] 1> D:\libraries\cpp\boost\boost_1_55_0\boost/bind/bind_template.hpp(47): Siehe Verweis auf die Instanziierung der gerade kompilierten Funktions-template "void boost::_bi::list2<boost::_bi::value<T>,boost::arg<1>>::operator ()<F,boost::_bi::list1<const A1 &>>(boost::_bi::type<void>,F &,A &,int)". 1> with 1> [ 1> T=tuc::nw::CMessageServer * 1> , F=boost::_mfi::mf1<void,tuc::nw::CMessageServer,tuc::nw::Packet &> 1> , A1=tuc::nw::Packet 1> , A=boost::_bi::list1<const tuc::nw::Packet &> 1> ] 1> D:\libraries\cpp\boost\boost_1_55_0\boost/bind/protect.hpp(60): Siehe Verweis auf die Instanziierung der gerade kompilierten Funktions-template "void boost::_bi::bind_t<void,boost::_mfi::mf1<void,tuc::nw::CMessageServer,tuc::nw::Packet &>,boost::_bi::list2<boost::_bi::value<T>,boost::arg<1>>>::operator ()<A1>(const A1 &)". 1> with 1> [ 1> T=tuc::nw::CMessageServer * 1> , A1=tuc::nw::Packet 1> ] 1> D:\libraries\cpp\boost\boost_1_55_0\boost/bind/protect.hpp(60): Siehe Verweis auf die Instanziierung der gerade kompilierten Funktions-template "void boost::_bi::bind_t<void,boost::_mfi::mf1<void,tuc::nw::CMessageServer,tuc::nw::Packet &>,boost::_bi::list2<boost::_bi::value<T>,boost::arg<1>>>::operator ()<A1>(const A1 &)". 1> with 1> [ 1> T=tuc::nw::CMessageServer * 1> , A1=tuc::nw::Packet 1> ] 1> G:\Quellcode\nc-programming\nc-libs\nc-libs/network/MessageChannel.h(196): Siehe Verweis auf die Instanziierung der gerade kompilierten Funktions-template "void boost::_bi::protected_bind_t<boost::_bi::bind_t<void,boost::_mfi::mf1<void,tuc::nw::CMessageServer,tuc::nw::Packet &>,boost::_bi::list2<boost::_bi::value<T>,boost::arg<1>>>>::operator ()<tuc::nw::Packet>(const A1 &)". 1> with 1> [ 1> T=tuc::nw::CMessageServer * 1> , A1=tuc::nw::Packet 1> ] 1> G:\Quellcode\nc-programming\nc-libs\nc-libs/network/MessageChannel.h(196): Siehe Verweis auf die Instanziierung der gerade kompilierten Funktions-template "void boost::_bi::protected_bind_t<boost::_bi::bind_t<void,boost::_mfi::mf1<void,tuc::nw::CMessageServer,tuc::nw::Packet &>,boost::_bi::list2<boost::_bi::value<T>,boost::arg<1>>>>::operator ()<tuc::nw::Packet>(const A1 &)". 1> with 1> [ 1> T=tuc::nw::CMessageServer * 1> , A1=tuc::nw::Packet 1> ] 1> G:\Quellcode\nc-programming\nc-libs\nc-libs/network/MessageChannel.h(179): Siehe Verweis auf die Instanziierung der gerade kompilierten Funktions-template "void tuc::nw::CMessageChannel::handleAsyncReadBody<T>(const boost::system::error_code &,size_t,T)". 1> with 1> [ 1> T=boost::_bi::protected_bind_t<boost::_bi::bind_t<void,boost::_mfi::mf1<void,tuc::nw::CMessageServer,tuc::nw::Packet &>,boost::_bi::list2<boost::_bi::value<tuc::nw::CMessageServer *>,boost::arg<1>>>> 1> ] 1> G:\Quellcode\nc-programming\nc-libs\nc-libs/network/MessageChannel.h(127): Siehe Verweis auf die Instanziierung der gerade kompilierten Funktions-template "void tuc::nw::CMessageChannel::handleAsyncReadHeader<T>(const boost::system::error_code &,size_t,T)". 1> with 1> [ 1> T=boost::_bi::protected_bind_t<boost::_bi::bind_t<void,boost::_mfi::mf1<void,tuc::nw::CMessageServer,tuc::nw::Packet &>,boost::_bi::list2<boost::_bi::value<tuc::nw::CMessageServer *>,boost::arg<1>>>> 1> ] 1> G:\Quellcode\nc-programming\nc-libs\nc-libs/network/MessageChannel.h(117): Siehe Verweis auf die Instanziierung der gerade kompilierten Funktions-template "void tuc::nw::CMessageChannel::startAsyncReadImpl<boost::_bi::protected_bind_t<boost::_bi::bind_t<void,boost::_mfi::mf1<void,tuc::nw::CMessageServer,tuc::nw::Packet &>,boost::_bi::list2<boost::_bi::value<T>,boost::arg<1>>>>>(boost::_bi::protected_bind_t<boost::_bi::bind_t<void,boost::_mfi::mf1<void,tuc::nw::CMessageServer,tuc::nw::Packet &>,boost::_bi::list2<boost::_bi::value<T>,boost::arg<1>>>> &&)". 1> with 1> [ 1> T=tuc::nw::CMessageServer * 1> ] 1> G:\Quellcode\nc-programming\nc-libs\nc-libs/network/MessageChannel.h(76): Siehe Verweis auf die Instanziierung der gerade kompilierten Funktions-template "void tuc::nw::CMessageChannel::startAsyncRead<void,boost::_mfi::mf1<void,tuc::nw::CMessageServer,tuc::nw::Packet &>,boost::_bi::list2<boost::_bi::value<T>,boost::arg<1>>>(boost::_bi::bind_t<void,boost::_mfi::mf1<void,tuc::nw::CMessageServer,tuc::nw::Packet &>,boost::_bi::list2<boost::_bi::value<T>,boost::arg<1>>>)". 1> with 1> [ 1> T=tuc::nw::CMessageServer * 1> ] 1> MessageServer.cpp(43): Siehe Verweis auf die Instanziierung der gerade kompilierten Funktions-template "void tuc::nw::CMessageChannel::startProcessing<boost::_bi::bind_t<void,boost::_mfi::mf1<void,tuc::nw::CMessageServer,tuc::nw::Packet &>,boost::_bi::list2<boost::_bi::value<T>,boost::arg<1>>>>(boost::_bi::bind_t<void,boost::_mfi::mf1<void,tuc::nw::CMessageServer,tuc::nw::Packet &>,boost::_bi::list2<boost::_bi::value<T>,boost::arg<1>>> &&,bool)". 1> with 1> [ 1> T=tuc::nw::CMessageServer * 1> ] ========== Erstellen: 0 erfolgreich, 1 fehlerhaft, 0 aktuell, 0 übersprungen ==========

2 1

installing boost getting error "ld: symbol(s) not found for architecture x86_64" on OSX 10.9.2
by Corentin Hamel 02 Apr '14

02 Apr '14

Hi everyone, I hope this is the right place to ask my question. I'm trying to build boost 1.55.0 for python on OSX 10.9.2 but i'm encountering the following error "ld: symbol(s) not found for architecture x86_64" and I'm really blocked. I read it might be related to the standard c++ library which changed with maverick to be libc++ by default. But even adding cxxflags="-stdlib=libstdc++" when executing ./b2 didn't help. Here is what I did following the boost tutorial: download boost_1_55_0.tar ./bootstrap.sh --with-libraries=python toolset=darwin ./b2 include="/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7/" And I get the following error: link.jam: No such file or directory Building the Boost C++ Libraries. error: No best alternative for /python_for_extensions next alternative: required properties: <python>2.7 <target-os>darwin matched next alternative: required properties: <python>2.7 <target-os>darwin matched error: No best alternative for /python_for_extensions next alternative: required properties: <python>2.7 <target-os>darwin matched next alternative: required properties: <python>2.7 <target-os>darwin matched Component configuration: - python : building darwin.link.dll bin.v2/libs/python/build/darwin-4.2.1/release/threading- multi/libboost_python.dylib Undefined symbols for architecture x86_64: "_PyFile_FromString", referenced from: boost::python::exec_file(boost::python::str, boost::python::api::object, boost::python::api::object) in exec.o "_PyFile_AsFile", referenced from: boost::python::exec_file(boost::python::str, boost::python::api::object, boost::python::api::object) in exec.o "_PyEval_GetGlobals", referenced from: boost::python::eval(boost::python::str, boost::python::api::object, boost::python::api::object) in exec.o boost::python::exec(boost::python::str, boost::python::api::object, boost::python::api::object) in exec.o boost::python::exec_statement(boost::python::str, boost::python::api::object, boost::python::api::object) in exec.o boost::python::exec_file(boost::python::str, boost::python::api::object, boost::python::api::object) in exec.o "_PyRun_StringFlags", referenced from: ........ "_PyExc_StopIteration", referenced from: boost::python::objects::stop_iteration_error() in iterator.o "_PyNumber_InPlaceAdd", referenced from: boost::python::api::operator+=(boost::python::api::object&, boost::python::api::object const&) in object_operators.o "_PyUnicodeUCS2_FromEncodedObject", referenced from: _encode_string_unaryfunc in builtin_converters.o "_PyErr_NoMemory", referenced from: boost::python::handle_exception_impl(boost::function0<void>) in errors.o "_PyDict_New", referenced from: boost::python::detail::dict_base::dict_base() in dict.o boost::python::detail::dict_base::dict_base() in dict.o _instance_get_dict in class.o ld: symbol(s) not found for architecture x86_64 clang: error: linker command failed with exit code 1 (use -v to see invocation) "g++" -dynamiclib -Wl,-single_module -install_name "libboost_python.dylib" -o "bin.v2/libs/python/build/darwin-4.2.1/release/threading-multi/libboost_python.dylib" "bin.v2/libs/python/build/darwin-4.2.1/release/threading-multi/numeric.o" "bin.v2/libs/python/build/darwin-4.2.1/release/threading-multi/list.o" "bin.v2/libs/python/build/darwin-4.2.1/release/threading-multi/long.o" "bin.v2/libs/python/build/darwin-4.2.1/release/threading-multi/dict.o" "bin.v2/libs/python/build/darwin-4.2.1/release/threading-multi/tuple.o" "bin.v2/libs/python/build/darwin-4.2.1/release/threading-multi/str.o" "bin.v2/libs/python/build/darwin-4.2.1/release/threading-multi/slice.o" "bin.v2/libs/python/build/darwin-4.2.1/release/threading-multi/converter/from_python.o" "bin.v2/libs/python/build/darwin-4.2.1/release/threading-multi/converter/registry.o" "bin.v2/libs/python/build/darwin-4.2.1/release/threading-multi/converter/type_id.o" "bin.v2/libs/python/build/darwin-4.2.1/release/threading-multi/object/enum.o" "bin.v2/libs/python/build/darwin-4.2.1/release/threading-multi/object/class.o" "bin.v2/libs/python/build/darwin-4.2.1/release/threading-multi/object/function.o" "bin.v2/libs/python/build/darwin-4.2.1/release/threading-multi/object/inheritance.o" "bin.v2/libs/python/build/darwin-4.2.1/release/threading-multi/object/life_support.o" "bin.v2/libs/python/build/darwin-4.2.1/release/threading-multi/object/pickle_support.o" "bin.v2/libs/python/build/darwin-4.2.1/release/threading-multi/errors.o" "bin.v2/libs/python/build/darwin-4.2.1/release/threading-multi/module.o" "bin.v2/libs/python/build/darwin-4.2.1/release/threading-multi/converter/builtin_converters.o" "bin.v2/libs/python/build/darwin-4.2.1/release/threading-multi/converter/arg_to_python_base.o" "bin.v2/libs/python/build/darwin-4.2.1/release/threading-multi/object/iterator.o" "bin.v2/libs/python/build/darwin-4.2.1/release/threading-multi/object/stl_iterator.o" "bin.v2/libs/python/build/darwin-4.2.1/release/threading-multi/object_protocol.o" "bin.v2/libs/python/build/darwin-4.2.1/release/threading-multi/object_operators.o" "bin.v2/libs/python/build/darwin-4.2.1/release/threading-multi/wrapper.o" "bin.v2/libs/python/build/darwin-4.2.1/release/threading-multi/import.o" "bin.v2/libs/python/build/darwin-4.2.1/release/threading-multi/exec.o" "bin.v2/libs/python/build/darwin-4.2.1/release/threading-multi/object/function_doc_signature.o" -headerpad_max_install_names -Wl,-dead_strip -no_dead_strip_inits_and_terms ...failed darwin.link.dll bin.v2/libs/python/build/darwin-4.2.1/release/threading- multi/libboost_python.dylib... ...skipped <pstage/lib>libboost_python.dylib for lack of <pbin.v2/libs/python/build/darwin- 4.2.1/release/threading-multi>libboost_python.dylib... ...failed updating 1 target... ...skipped 1 target... Thanks for your help! Corentin Hamel Software Engineer Rocketboots Level 11, 189 Kent Street Sydney NSW 2000

2 5

boost asio synchronous vs asynchronous operations performance
by Donald Alan 31 Mar '14

31 Mar '14

Hi, I'm trying to compare the performance of boost::asio asynchronous vs synchronous IO operations for a single client. Below, I've sample synchronous and asynchronous server applications, which send 25 byte message to the client in a loop continuously. On the client side, I'm checking at what rate it is able to receive the messages. The sample setup is pretty simple. In synchronous server case, it spawns a new thread per client connection and the thread keeps sending the 25-byte message in a loop. In asynchronous server case as well it spawns a new thread per client connection and the thread keeps sending the 25-byte message in a loop, using asynchronous write (main thread is the one which calls ioservice.run()). For the performance testing I'm using only one client. *Synchronous server code* #include <iostream> #include <boost/bind.hpp> #include <boost/shared_ptr.hpp> #include <boost/enable_shared_from_this.hpp> #include <boost/asio.hpp> #include <boost/thread.hpp> using boost::asio::ip::tcp; class tcp_connection : public boost::enable_shared_from_this<tcp_connection> { public: typedef boost::shared_ptr<tcp_connection> pointer; static pointer create(boost::asio::io_service& io_service) { return pointer(new tcp_connection(io_service)); } tcp::socket& socket() { return socket_; } void start() { for (;;) { try { ssize_t len = boost::asio::write(socket_, boost::asio::buffer(message_)); if (len != message_.length()) { std::cerr<<"Unable to write all the bytes"<<std::endl; break; } if (len == -1) { std::cerr<<"Remote end closed the connection"<<std::endl; break; } } catch (std::exception& e) { std::cerr<<"Error while sending data"<<std::endl; break; } } } private: tcp_connection(boost::asio::io_service& io_service) : socket_(io_service), message_(25, 'A') { } tcp::socket socket_; std::string message_; }; class tcp_server { public: tcp_server(boost::asio::io_service& io_service) : acceptor_(io_service, tcp::endpoint(tcp::v4(), 1234)) { start_accept(); } private: void start_accept() { for (;;) { tcp_connection::pointer new_connection = tcp_connection::create(acceptor_.get_io_service()); acceptor_.accept(new_connection->socket()); boost::thread(boost::bind(&tcp_connection::start, new_connection)); } } tcp::acceptor acceptor_; }; int main() { try { boost::asio::io_service io_service; tcp_server server(io_service); } catch (std::exception& e) { std::cerr << e.what() << std::endl; } return 0; } *ASynchronous server code:* #include <iostream> #include <string> #include <boost/bind.hpp> #include <boost/shared_ptr.hpp> #include <boost/enable_shared_from_this.hpp> #include <boost/asio.hpp> #include <boost/thread.hpp> using boost::asio::ip::tcp; class tcp_connection : public boost::enable_shared_from_this<tcp_connection> { public: typedef boost::shared_ptr<tcp_connection> pointer; static pointer create(boost::asio::io_service& io_service) { return pointer(new tcp_connection(io_service)); } tcp::socket& socket() { return socket_; } void start() { while (socket_.is_open()) { boost::asio::async_write(socket_, boost::asio::buffer(message_), boost::bind(&tcp_connection::handle_write, shared_from_this(), boost::asio::placeholders::error, boost::asio::placeholders::bytes_transferred)); } } private: tcp_connection(boost::asio::io_service& io_service) : socket_(io_service), message_(25, 'A') { } void handle_write(const boost::system::error_code& error, size_t bytes_transferred) { if (error) { if (socket_.is_open()) { std::cout<<"Error while sending data asynchronously"<<std::endl; socket_.close(); } } } tcp::socket socket_; std::string message_; }; class tcp_server { public: tcp_server(boost::asio::io_service& io_service) : acceptor_(io_service, tcp::endpoint(tcp::v4(), 1234)) { start_accept(); } private: void start_accept() { tcp_connection::pointer new_connection = tcp_connection::create(acceptor_.get_io_service()); acceptor_.async_accept(new_connection->socket(), boost::bind(&tcp_server::handle_accept, this, new_connection, boost::asio::placeholders::error)); } void handle_accept(tcp_connection::pointer new_connection, const boost::system::error_code& error) { if (!error) { boost::thread(boost::bind(&tcp_connection::start, new_connection)); } start_accept(); } tcp::acceptor acceptor_; }; int main() { try { boost::asio::io_service io_service; tcp_server server(io_service); io_service.run(); } catch (std::exception& e) { std::cerr << e.what() << std::endl; } return 0; } *Client code* #include <iostream> #include <boost/asio.hpp> #include <boost/array.hpp> int main(int argc, char* argv[]) { if (argc != 3) { std::cerr<<"Usage: client <server-host> <server-port>"<<std::endl; return 1; } boost::asio::io_service io_service; boost::asio::ip::tcp::resolver resolver(io_service); boost::asio::ip::tcp::resolver::query query(argv[1], argv[2]); boost::asio::ip::tcp::resolver::iterator it = resolver.resolve(query); boost::asio::ip::tcp::resolver::iterator end; boost::asio::ip::tcp::socket socket(io_service); boost::asio::connect(socket, it); // Statscollector to periodically print received messages stats // sample::myboost::StatsCollector stats_collector(5); // sample::myboost::StatsCollectorScheduler statsScheduler(stats_collector); // statsScheduler.start(); for (;;) { boost::array<char, 25> buf; boost::system::error_code error; size_t len = socket.read_some(boost::asio::buffer(buf), error); // size_t len = boost::asio::read(socket, boost::asio::buffer(buf)); if (len != buf.size()) { std::cerr<<"Length is not "<< buf.size() << " but "<<len<<std::endl; } // stats_collector.incr_msgs_received(); } } <b>Question:* When the client is running against synchronous server it is able to receive around 700K msgs/sec but when it is running against asynchronous server the performance is dropped to around 100K-120K msgs/sec. I know that one should use asynchronous IO for scalability when we have more number of clients and in the above case as I'm using only a single client, the obvious advantage of asynchronous IO is not evident. But the question is, is asynchronous IO expected to effect the performance so badly for a single client case or am I missing some obvious best practices to follow with asynchronous IO? Is the significant drop in the performance is because of the thread switch between ioservice thread (which is main thread in the above case) and connection thread? *Setup:* I'm using BOOST 1.47 on Linux machine. -- View this message in context: http://boost.2283326.n4.nabble.com/boost-asio-synchronous-vs-asynchronous-o… Sent from the Boost - Users mailing list archive at Nabble.com.

6 18

[fusion 1.55.0] fusion::map avoid copy construction for elements
by Frank Bergemann 30 Mar '14

30 Mar '14

3 2