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[ASIO] "perf" shows overhead of function calls is very high
by Junchang Wang 19 Nov '12

19 Nov '12

Hi list, I'm new to Boost.asio and am solving scaling problems of a Openflow (TCP based) server. We are using one single io_service for packets receiving and transmitting. A thread pool calling io_service::run() processes HTTP requests. A multi-core server is used. I found we can't get benefits from increasing the size of thread pool when it's size is larger than 6. In other words the system doesn't scale any more on more than 6 cores. I checked the program carefully and can make sure there's … [View More]no lock contention. I profile the program with Linux perf, and it turns out up to 36% of CPU time is wasted in function calls. 36.39% : 0000000000103300 <boost::detail::function::void_function_obj_invoker3<vigil::openflow::v1::construct_and_load<vigil::openflow::v1::ofp_packet_out, vigil:: : BOOST_FUNCTION_TEMPLATE_PARMS : > : struct BOOST_FUNCTION_VOID_FUNCTION_OBJ_INVOKER : { : static BOOST_FUNCTION_VOID_RETURN_TYPE : invoke(function_buffer& function_obj_ptr BOOST_FUNCTION_COMMA 0.02 : 103300: push %rbp 99.66 : 103301: mov %rsp,%rbp 0.00 : 103304: push %r12 0.04 : 103306: mov %rcx,%r12 I printed out the call stack (attached at the tail of this email). It seems for a single packet processing there are more than 30 function calls within Boost. Can that explain why the CPU time on function calls is so high? Are there some ways to avoid this kind of cost? Thanks a lot. --Junchang ================ #0 vigil::openflow::Openflow_datapath::send (this=<optimized out>, msg=0x7ffff567f920) at ../../../../src/coreapps/openflow/openflow-datapath.cc:199 #1 0x00007ffff4c50724 in vigil::openflow::Openflow_datapath::handle_handshake (this=0x7ffff007dd80, e=...) at ../../../../src/coreapps/openflow/openflow-datapath.cc:305 #2 0x00007ffff4c5086a in vigil::openflow::Openflow_datapath::handle_message (this=0x7ffff007dd80, msg=0x7ffff567f920) at ../../../../src/coreapps/openflow/openflow-datapath.cc:228 #3 0x00007ffff4c50a39 in vigil::openflow::Openflow_datapath::recv_cb (this=0x7ffff007dd80, bytes_transferred=<optimized out>) at ../../../../src/coreapps/openflow/openflow-datapath.cc:164 #4 0x00007ffff7bad130 in operator() (a0=<optimized out>, this=0x7ffff007d4b8) at /usr/include/boost/function/function_template.hpp:1013 #5 vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp, boost::asio::stream_socket_service<boost::asio::ip::tcp> > >::handle_recv ( this=0x7ffff007d480, ec=..., bytes_transferred=<optimized out>) at ../../../src/lib/connection.cc:185 #6 0x00007ffff7bb5fba in call<boost::shared_ptr<vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> > >, boost::system::error_code const, unsigned long const> (b2=@0x7ffff568fa10: 8, b1=..., u=..., this=0x7ffff568f9e0) at /usr/include/boost/bind/mem_fn_template.hpp:271 #7 operator()<boost::shared_ptr<vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> > > > (u=..., this=0x7ffff568f9e0, a2=@0x7ffff568fa10: 8, a1=...) at /usr/include/boost/bind/mem_fn_template.hpp:286 #8 operator()<boost::_mfi::mf2<void, vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> >, const boost::system::error_code&, const long unsigned int&>, boost::_bi::list2<const boost::system::error_code&, const long unsigned int&> > (a=<synthetic pointer>, f=..., this=0x7ffff568f9f0) at /usr/include/boost/bind/bind.hpp:392 #9 operator()<boost::system::error_code, long unsigned int> (a2=@0x7ffff568fa10: 8, a1=..., this=0x7ffff568f9e0) at /usr/include/boost/bind/bind_template.hpp:102 #10 operator() (this=0x7ffff568f9e0) at /usr/include/boost/asio/detail/bind_handler.hpp:97 #11 asio_handler_invoke<boost::asio::detail::binder2<boost::_bi::bind_t<void, boost::_mfi::mf2<void, vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> >, boost::system::error_code const&, unsigned long const&>, boost::_bi::list3<boost::_bi::value<boost::shared_ptr<vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> > > >, boost::arg<1> (*)(), boost::arg<2> (*)()> >, boost::system::error_code, unsigned long> > ( function=<error reading variable: access outside bounds of object referenced via synthetic pointer>) at /usr/include/boost/asio/handler_invoke_hook.hpp:64 #12 boost_asio_handler_invoke_helpers::invoke<boost::asio::detail::binder2<boost::_bi::bind_t<void, boost::_mfi::mf2<void, vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> >, boost::system::error_code const&, unsigned long const&>, boost::_bi::list3<boost::_bi::value<boost::shared_ptr<vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> > > >, boost::arg<1> (*)(), boost::arg<2> (*)()> >, boost::system::error_code, unsigned long>, boost::_bi::bind_t<void, boost::_mfi::mf2<void, vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> >, boost::system::error_code const&, unsigned long const&>, boost::_bi::list3<boost::_bi::value<boost::shared_ptr<vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> > > >, boost::arg<1> (*)(), boost::arg<2> (*)()> > > (function=..., context=...) at /usr/include/boost/asio/detail/handler_invoke_helpers.hpp:39 #13 0x00007ffff7bb637b in asio_handler_invoke<boost::asio::detail::binder2<boost::_bi::bind_t<void, boost::_mfi::mf2<void, vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> >, boost::system::error_code const&, unsigned long const&>, boost::_bi::list3<boost::_bi::value<boost::shared_ptr<vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> > > >, boost::arg<1> (*)(), boost::arg<2> (*)()> >, boost::system::error_code, unsigned long>, boost::_bi::bind_t<void, boost::_mfi::mf2<void, vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> >, boost::system::error_code const&, unsigned long const&>, boost::_bi::list3<boost::_bi::value<boost::shared_ptr<vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> > > >, boost::arg<1> (*)(), boost::arg<2> (*)()> >, boost::system::error_code, unsigned long> (this_handler=0x7ffff568fbf0, function=...) at /usr/include/boost/asio/detail/bind_handler.hpp:132 #14 invoke<boost::asio::detail::binder2<boost::_bi::bind_t<void, boost::_mfi::mf2<void, vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> >, boost::system::error_code const&, unsigned long const&>, boost::_bi::list3<boost::_bi::value<boost::shared_ptr<vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> > > >, boost::arg<1> (*)(), boost::arg<2> (*)()> >, boost::system::error_code, unsigned long>, boost::asio::detail::binder2<boost::_bi::bind_t<void, boost::_mfi::mf2<void, vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> >, boost::system::error_code const&, unsigned long const&>, boost::_bi::list3<boost::_bi::value<boost::shared_ptr<vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> > > >, boost::arg<1> (*)(), boost::arg<2> (*)()> >, boost::system::error_code, unsigned long> > (context=..., function=...) at /usr/include/boost/asio/detail/handler_invoke_helpers.hpp:39 #15 boost::asio::detail::strand_service::dispatch<boost::asio::detail::binder2<boost::_bi::bind_t<void, boost::_mfi::mf2<void, vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp, boost::asio::stream_socket_service<boost::asio::ip::tcp> > >, boost::system::error_code const&, unsigned long const&>, boost::_bi::list3<boost::_bi::value<boost::shared_ptr<vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp, boost::asio::stream_socket_service<boost::asio::ip::tcp> > > > >, boost::arg<1> (*)(), boost::arg<2> (*)()> >, boost::system::error_code, unsigned long> > (this=0x7ffff0001560, impl=@0x7ffff568fbb0: 0x7ffff0047d80, handler=...) at /usr/include/boost/asio/detail/impl/strand_service.hpp:97 #16 0x00007ffff7bb66fa in dispatch<boost::asio::detail::binder2<boost::_bi::bind_t<void, boost::_mfi::mf2<void, vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> >, boost::system::error_code const&, unsigned long const&>, boost::_bi::list3<boost::_bi::value<boost::shared_ptr<vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> > > >, boost::arg<1> (*)(), boost::arg<2> (*)()> >, boost::system::error_code, unsigned long> > ( handler=<error reading variable: access outside bounds of object referenced via synthetic pointer>, this=0x7ffff568fba8) at /usr/include/boost/asio/strand.hpp:159 #17 operator()<boost::system::error_code, long unsigned int> (arg2=<synthetic pointer>, arg1=..., this=0x7ffff568fba8) at /usr/include/boost/asio/detail/wrapped_handler.hpp:65 #18 operator()<boost::system::error_code, long unsigned int> (arg2=<optimized out>, arg1=..., this=0x7ffff568fba0) at ../../../src/lib/connection.cc:64 #19 operator() (this=0x7ffff568fba0) at /usr/include/boost/asio/detail/bind_handler.hpp:97 #20 asio_handler_invoke<boost::asio::detail::binder2<vigil::custom_alloc_handler<boost::asio::detail::wrapped_handler<boost::asio::io_service::strand, boost::_bi::bind_t<void, boost::_mfi::mf2<void, vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> >, boost::system::error_code const&, unsigned long const&>, boost::_bi::list3<boost::_bi::value<boost::shared_ptr<vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> > > >, boost::arg<1> (*)(), boost::arg<2> (*)()> > > >, boost::system::error_code, unsigned long> > (function=<error reading variable: access outside bounds of object referenced via synthetic pointer>) at /usr/include/boost/asio/handler_invoke_hook.hpp:64 #21 invoke<boost::asio::detail::binder2<vigil::custom_alloc_handler<boost::asio::detail::wrapped_handler<boost::asio::io_service::strand, boost::_bi::bind_t<void, boost::_mfi::mf2<void, vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> >, boost::system::error_code const&, unsigned long const&>, boost::_bi::list3<boost::_bi::value<boost::shared_ptr<vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> > > >, boost::arg<1> (*)(), boost::arg<2> (*)()> > > >, boost::system::error_code, unsigned long>, vigil::custom_alloc_handler<boost::asio::detail::wrapped_handler<boost::asio::io_service::strand, boost::_bi::bind_t<void, boost::_mfi::mf2<void, vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> >, boost::system::error_code const&, unsigned long const&>, boost::_bi::list3<boost::_bi::value<boost::shared_ptr<vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp> > > >, boost::arg<1> (*)(), boost::arg<2> (*)()> > > > > (function=..., context=...) at /usr/include/boost/asio/detail/handler_invoke_helpers.hpp:39 #22 boost::asio::detail::reactive_socket_recv_op<boost::asio::mutable_buffers_1, vigil::custom_alloc_handler<boost::asio::detail::wrapped_handler<boost::asio::io_service::strand, boost::_bi::bind_t<void, boost::_mfi::mf2<void, vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp, boost::asio::stream_socket_service<boost::asio::ip::tcp> > >, boost::system::error_code const&, unsigned long const&>, boost::_bi::list3<boost::_bi::value<boost::shared_ptr<vigil::Stream_connection<boost::asio::basic_stream_socket<boost::asio::ip::tcp, boost::asio::stream_socket_service<boost::asio::ip::tcp> > > > >, boost::arg<1> (*)(), boost::arg<2> (*)()> > > > >::do_complete (owner=0x6d6b30, base=<optimized out>) at /usr/include/boost/asio/detail/reactive_socket_recv_op.hpp:106 #23 0x0000000000487343 in complete (owner=..., this=0x7ffff007d510) at /usr/include/boost/asio/detail/task_io_service_operation.hpp:35 #24 boost::asio::detail::task_io_service::do_one (this=0x6d6b30, lock=..., this_idle_thread=0x7ffff568fdd0) at /usr/include/boost/asio/detail/impl/task_io_service.ipp:278 #25 0x00000000004874b0 in boost::asio::detail::task_io_service::run (this=0x6d6b30, ec=...) at /usr/include/boost/asio/detail/impl/task_io_service.ipp:130 #26 0x00000000004875c9 in boost::asio::io_service::run (this=0x6d68f8) at /usr/include/boost/asio/impl/io_service.ipp:57 #27 0x00007ffff7971ce9 in thread_proxy () from /usr/lib/libboost_thread.so.1.46.1 #28 0x00007ffff5f2ee9a in start_thread () from /lib/x86_64-linux-gnu/libpthread.so.0 #29 0x00007ffff6237cbd in clone () from /lib/x86_64-linux-gnu/libc.so.6 #30 0x0000000000000000 in ?? () [View Less]

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code review please? [boost::asio]
by Littlefield, Tyler 18 Nov '12

18 Nov '12

hello all: I was curious if some boost::asio guru would mind checking this out. I just posted my code in, I'd like to know if there's anything that could be done better. Thanks, //client.h #pragma once #include <queue> #include <boost/asio.hpp> #include <boost/bind.hpp> #include "ClientBuffer.h" class Client { protected: boost::asio::ip::tcp::socket _socket; boost::asio::io_service &_service; std::queue<ClientBuffer*> _buffers; bool _writing; … [View More] void StartWrite(); void HandleWrite(const boost::system::error_code& error); public: Client(boost::asio::io_service &service); ~Client(); virtual boost::asio::ip::tcp::socket& GetSocket(); virtual void Start() = 0; void Write(const char* data); void Write(void* data, unsigned int size); void Write(const std::string &data); }; //client.cpp #include <boost/asio.hpp> #include <boost/bind.hpp> #include "client.h" #include "ClientBuffer.h" Client::Client(boost::asio::io_service &service): _service(service), _socket(service), _writing(false) { } Client::~Client() { } void Client::StartWrite() { //we don't write if we're already writing. We just content ourselves with having pushed the message to the queue. if (_writing) { return; } //we're writing now. _writing = true; ClientBuffer* buffer = NULL; buffer = _buffers.front(); boost::asio::async_write(_socket, boost::asio::buffer(buffer->GetBuffer(), buffer->GetSize()), boost::bind(&Client::HandleWrite, this, boost::asio::placeholders::error)); } void Client::HandleWrite(const boost::system::error_code& error) { if (_buffers.empty()) { _writing = false; return; } ClientBuffer* buffer = _buffers.front(); _buffers.pop(); if (buffer) delete buffer; if (_buffers.empty()) _writing = false; else StartWrite(); } boost::asio::ip::tcp::socket& Client::GetSocket() { return _socket; } void Client::Write(const char* data) { ClientBuffer* buffer = new ClientBuffer(data); _buffers.push(buffer); StartWrite(); } void Client::Write(void* data, unsigned int size) { ClientBuffer* buffer = new ClientBuffer(data, size); _buffers.push(buffer); StartWrite(); } void Client::Write(const std::string &data) { ClientBuffer* buffer = new ClientBuffer(data); _buffers.push(buffer); StartWrite(); } //TelnetClient.h /* *this client is responsible for handling the telnet protocol. */ #pragma once #include <boost/asio.hpp> #include <boost/bind.hpp> #include "client.h" #include "ClientBuffer.h" class TelnetClient:public Client { int _state; boost::asio::streambuf _buffer; public: virtual void Start(); void Read(); void HandleRead(const boost::system::error_code& error); void HandleCommand(const std::string &line); }; //TelnetClient.cpp #include <string> #include <istream> #include <boost/asio.hpp> #include <boost/bind.hpp> #include "client.h" #include "TelnetClient.h" void TelnetClient::Start() { Write("Welcome to SapphireMud.\n"); Write("Use load <player> <password> to load a character.\n"); Write("Use create <player> <password> to create a new player.\n"); _state = 1; Read(); } void TelnetClient::Read() { boost::asio::async_read_until(_socket, _buffer, '\n', boost::bind(&TelnetClient::HandleRead, this, boost::asio::placeholders::error)); } void TelnetClient::HandleRead(const boost::system::error_code& error) { char buffer[2048]; if (error) { //do something here return; } std::istream input(&_buffer); input.getline(buffer, 2048); HandleCommand(buffer); Read(); } void TelnetClient::HandleCommand(const std::string &line) { Write("I don't understand that!\n"); } -- Take care, Ty http://tds-solutions.net The aspen project: a barebones light-weight mud engine: http://code.google.com/p/aspenmud He that will not reason is a bigot; he that cannot reason is a fool; he that dares not reason is a slave. [View Less]

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Re: [Boost-users] What is the best idiom for using call_once ?
by John M. Dlugosz 18 Nov '12

18 Nov '12

Date: Sat, 17 Nov 2012 13:51:48 +0100 From: "Vicente J. Botet Escriba" <vicente.botet(a)wanadoo.fr> > Hi, your code suffers from the problem you try to avoid "But we all know this is not > thread safe, at least for the first call" at least in c++98 as you are using static > variables. Actually, my post described the circumstances under which it does in fact work: when VarType has a built-in type that is initialized before program execution, or on C++11 with a constexpr … [View More]

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What is the best idiom for using call_once ?
by John M. Dlugosz 17 Nov '12

17 Nov '12

Consider the issue of a static variable inside a function: the idea is to initialize on first use (if any). But we all know this is not thread safe, at least for the first call. Since the C++11 standard library includes a feature just like boost::call_once, that would seem to be the proper way to address this moving forward. And, I don't see anything in the standard that would be more powerful and direct for this purpose, which leaves me to wonder if there is still more that should have … [View More]

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Re: [Boost-users] Boost 1.52 .zip bootstrap file -- missing?
by Adam J. Cooper 17 Nov '12

17 Nov '12

I downloaded "boost_1_52_0.zip" from here on 11/16 http://www.boost.org/users/history/version_1_52_0.html I used the native unzip built into Windows 8. There were two folders in the root directory, docs and source files. There was no bootstrap file or any other tools files. - Adam ------------------------------ Message: 2 Date: Sat, 17 Nov 2012 10:13:55 +0000 From: Daniel James <dnljms(a)gmail.com> To: boost-users(a)lists.boost.org Subject: Re: [Boost-users] Boost 1.52 .zip … [View More]

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Boost 1.52 .zip bootstrap file -- missing?
by Adam J. Cooper 17 Nov '12

17 Nov '12

I download the .zip version of Boost 1.52 However, I do not see the bootstrap file when I unzip the contents. Please advise. Thank you, Adam

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(no subject)
by mega deth 16 Nov '12

16 Nov '12

http://mcrtaky.org/wp-content/themes/twentyeleven/hotnews.php?youth293.gif

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Updated serialization performance tests
by Brian Wood 16 Nov '12

16 Nov '12

Shalom I've updated this page -- http://webEbenezer.net/comparison.html with results from Boost 1.52. A few notes about the testing: I decided to use -O2 on the Linux/g++ tests. In previous tests I used -O3. I hadn't updated the Windows test results since the Boost 1.48 time-frame. Around Boost 1.51 I had to start building the serialization library in Boost with runtime-link=static in order to get the Windows tests to build. I haven't understood why that became necessary, but the … [View More]

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how to build a release version of my application from source control using boost libs?
by Anil 16 Nov '12

16 Nov '12

Trying to build a release version from source code put into Clearcase source control. Boost is installed on my computer hard disk. what libraries should I copy to the repository? I tried copying libboost_regex-vc90-mt-gd-1_51.lib but it still gave an error. 1>------ Build started: Project: MyApplication, Configuration: Release Win32 ------ 1>Compiling... 1>MyApplication.cpp 1>.\MyApplication.cpp(40) : warning C4627: '#include <boost/property_tree/ptree.hpp>': skipped when … [View More]looking for precompiled header use 1> Add directive to 'stdafx.h' or rebuild precompiled header 1>.\MyApplication.cpp(41) : warning C4627: '#include <boost/property_tree/xml_parser.hpp>': skipped when looking for precompiled header use 1> Add directive to 'stdafx.h' or rebuild precompiled header 1>.\MyApplication.cpp(42) : warning C4627: '#include <boost/foreach.hpp>': skipped when looking for precompiled header use 1> Add directive to 'stdafx.h' or rebuild precompiled header 1>.\MyApplication.cpp(43) : warning C4627: '#include <boost/lexical_cast.hpp>': skipped when looking for precompiled header use 1> Add directive to 'stdafx.h' or rebuild precompiled header 1>.\MyApplication.cpp(44) : warning C4627: '#include <string>': skipped when looking for precompiled header use 1> Add directive to 'stdafx.h' or rebuild precompiled header 1>.\MyApplication.cpp(45) : warning C4627: '#include <set>': skipped when looking for precompiled header use 1> Add directive to 'stdafx.h' or rebuild precompiled header 1>.\MyApplication.cpp(46) : warning C4627: '#include <exception>': skipped when looking for precompiled header use 1> Add directive to 'stdafx.h' or rebuild precompiled header 1>.\MyApplication.cpp(47) : warning C4627: '#include <iostream>': skipped when looking for precompiled header use 1> Add directive to 'stdafx.h' or rebuild precompiled header 1>.\MyApplication.cpp(48) : warning C4627: '#include <fstream>': skipped when looking for precompiled header use 1> Add directive to 'stdafx.h' or rebuild precompiled header 1>.\MyApplication.cpp(49) : warning C4627: '#include "MyApplication.h"': skipped when looking for precompiled header use 1> Add directive to 'stdafx.h' or rebuild precompiled header 1>.\MyApplication.cpp(50) : warning C4627: '#include <boost/filesystem.hpp>': skipped when looking for precompiled header use 1> Add directive to 'stdafx.h' or rebuild precompiled header 1>.\MyApplication.cpp(51) : warning C4627: '#include <boost/regex.hpp>': skipped when looking for precompiled header use 1> Add directive to 'stdafx.h' or rebuild precompiled header 1>.\MyApplication.cpp(875) : fatal error C1010: unexpected end of file while looking for precompiled header. Did you forget to add '#include "stdafx.h"' to your source? 1>Build log was saved at "file://a:\MyApplication\Release\BuildLog.htm" 1>MyApplication - 1 error(s), 12 warning(s) ========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ========== how to build a release version of my application from source control using boost libs? [View Less]

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Newbie-Question: recursive_directory_iterator and Unicode
by Andy 16 Nov '12

16 Nov '12

Hi all, i'm using the following code-part to show a file-listing of the current directory: boost::locale::generator gen; std::locale l = gen(""); std::locale::global(l); boost::filesystem::recursive_directory_iterator it(L"."); boost::filesystem::recursive_directory_iterator itEnd; while (it != itEnd) { if (boost::filesystem::status_known(it->status()) && boost::filesystem::is_regular(it->status())) { cout << it->path() << … [View More]

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