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[gsoc] Example of exceptional project proposal
by Mateusz Loskot 24 Mar '20

24 Mar '20

...as it is not Dear students, if you aim to submit proposals like this, then please don't bother polluting the GSoC space with such rubbish. Please, let's display some minimum of professionalism and respect to each other. Best regards, -- Mateusz Loskot, http://mateusz.loskot.net

1 0

Uploading a file to a Boost Beast Server
by Bill Moo 24 Mar '20

24 Mar '20

I am using Beast 277 and code from the advanced server example as the basis for my own one. As part of the functionality I need to allow users the ability to upload a file to the server via their browser. So I had a look at the 'Deferred Body Type' in the examples provided but I can't see how I can make use of it in my own server, although I have tried but fall foul of the SyncReadStream. Is there a working example anywhere of how I can capture and save a file uploaded to the server by a user please. -- Bill

2 2

asio, beast and concepts
by David P. Riedel 24 Mar '20

24 Mar '20

Hi I have been experimenting with some C++20 concepts code. Currently, I have a program which uses beast and asio to do some network file transfers. I was thinking of adding a small piece of code to my code which includes a concept. Prior to doing this, I tried building the beast tests from the 1.72 version with concepts enabled in the compiler. I got lots of errors such as the one below. beast/http/write.cpp:313:44: error: use of ‘auto boost::beast::http::async_write(AsyncWriteStream&, const boost::beast::http::message<isRequest, Body, Fields>&, WriteHandler&&, typename std::enable_if<(! boost::beast::http::is_mutable_body_writer<Body>::value)>::type*) [with AsyncWriteStream = boost::beast::test::stream; bool isRequest = false; Body = boost::beast::http::basic_string_body<char>; Fields = boost::beast::http::basic_fields<std::allocator<char> >; WriteHandler = boost::asio::basic_yield_context<boost::asio::executor_binder<void (*)(), boost::asio::executor> >; typename std::enable_if<(! boost::beast::http::is_mutable_body_writer<Body>::value)>::type = void]’ before deduction of ‘auto’ 313 | async_write(ts, m, do_yield[ec]); | ^ Are beast and asio not concepts ready? Or am I missing something? Is there some flag I need to set? My set up: boost: 1.72 gcc: 9.3 I added -std=c++2a -fconcepts to compile flags in my user-config.jam file to enable compiler concepts support. I have no problems using these compiler flags with other non-boost code. Thanks

4 7

[Newbie][Interprocess] Placing a boost interprocess vector in an existing (not managed) shared memory
by Gaier, Bjoern 17 Mar '20

17 Mar '20

Hello Boost-Mailing-List, I have a question about the boost interprocess library - and I hope I can explain it correctly. I looked at the "Quick guide for the impatient" about the interprocess library - but I'm not sure if I can use this for our purpose. The main goal is to insert a STL vector (or different container) in a predefined portion of an already existing shared memory. The main problem is, that we cannot use the managed_shared_memory code from boost, because we rely on a different API to allocate the shared memory between Windows and other devices. Also the container should be placed at a fixed offset inside the created shared memory. I'm a complete newbie with boost and the interprocess library, that is why I'm not sure which interface I have to provide for the interprocess vector to be setup correctly. I hoped I could do something like: new (srh_mem_base + offset) boost::interprocess::vector<allocator>; I tried looking into the headers of the library to get an idea of that, but I honestly got lost. I'm really sorry if this a stupid or obvious question - and I thank for any help in advance! Kind greetings Björn Als GmbH eingetragen im Handelsregister Bad Homburg v.d.H. HRB 9816, USt.ID-Nr. DE 114 165 789 Geschäftsführer: Dr. Hiroshi Nakamura, Dr. Robert Plank, Markus Bode, Heiko Lampert, Takashi Nagano, Takeshi Fukushima. Junichi Tajika

3 3

Is iterator_facade still relevant in C++11, C++17?
by Mateusz Loskot 14 Mar '20

14 Mar '20

Hi, This is a bit theoretical question, but I'd like to collect some opinions. Considering sequence of C++ versions, around where, if at all, boost::iterator_facade shines less and becomes less relevant? In other words: - If you had to implement iterators in C++11, would you use it? - If you had to implement iterators in C++17, would you use it? Has anyone observed performance issues when using iterator_facade? Best regards, -- Mateusz Loskot, http://mateusz.loskot.net

3 4

bimap: one to many
by MM 13 Mar '20

13 Mar '20

Hello I want a collection to store a relationship N to M like so: Item of type A Item of type B A1 B1,B2,B3 A2 B4 A3 B1 and I would like a convenient way to get from a A instance to the list of B instances, and vice versa, from a given B instance to the list of A instances. At runtime, the A objects are created first, then a list of B objects is created. Later, B objects get modified asynchronously and that modification need to update the relevant A instances what container to use? boost::bimap< unordered_set<A*> , unordered_set<B*> > ?

3 2

Failing to build Boost
by MANAV KUMAR 13 Mar '20

13 Mar '20

Hi , I am Manav Kumar. I was trying to install boost version 1.72 on my system Mac OSX. But after installing the package from it’s website and running the ./bootstrap.sh command while being in it’s directory I am getting the following error :- ' Building Boost.Build engine with toolset clang… Failed to build Boost.Build build engine Consult ‘bootstrap.log’ for more details. ‘ And I am hardly able to understand the bootstrap.log file to figure out the problem. Somebody please help me with it. Regards Manav

2 1

shared memory objects limitation in Windows 10
by Shen, Chang (MSFC-EV43) 11 Mar '20

11 Mar '20

Hi All I am testing my class using boost. The class has a shared_memory_object member : class X { char* m_buffer; boost::interprocess::shared_memory_object *m_sram; public X(char *name) { m_buffer = (char*)malloc(128); m_sram = new(std::nothrow) boost::interprocess::shared_memory_object(boost::interprocess::open_or_create_t, name, boost::interprocess::mode_t::read_write); } } int main() { std::vector<X*> xlist; for(int i=0;i<1500;i++) { std::string name = std::to_string(i); X *x = new(std::nothrow) (name.c_str()); xlist.push_back(x); } return 0; } I test the class in Window 10 using MinGW 32bit compiler. g++ (MinGW.org GCC-8.2.0-3) 8.2.0 Copyright (C) 2018 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. I find that I only can create 1463 X objects. 1464th object will throw exception: Dynamic exception type: boost::interprocess::interprocess_exception std::exception::what: WinApi FormatMessage returned error. Why this limitation?

2 1

[Process] Hardcoding the command for shell
by Frederick Gotham 11 Mar '20

11 Mar '20

At the command line on most operating system, you can pipe a file into another program and then pipe out into a third program. For example: Take a file from the hard disk, decrypt it, and then unzip it: openssl rc4-40 -salt -d -pass pass:MyPassword < /home/frederick/monkey.tar.gz.encrypted > tar -zxf - I realise, when using Boost::Process, that we can tie the input and output streams of child processes together using 'ipstream', but I want to be able to take the above command and give it directly to the operating system (or to the 'shell'). On Linux x64 and armhf(32-Bit), the following works: child c(search_path("sh"), "-c", "openssl rc4-40 -salt -d -pass pass:MyPassword < /home/frederick/monkey.tar.gz.encrypted > tar -zxf -" ); But should I have to hardcode "sh" and "-c" into my program like that? I have tried using "shell" like this: child c( "openssl rc4-40 -salt -d -pass pass:MyPassword < /home/frederick/monkey.tar.gz.encrypted > tar -zxf -", shell ); but this doesn't work on either Linux x64 or armhf(32-Bit). I thought the whole point of "shell" was that you didn't have to hardcode "sh -c" in Linux or "cmd /c" in MS-Windows. Also if you do some web-searching for how to run a batch file in MS-Windows using boost::process, you'll see that everyone is doing this: context ctx; ctx.environment = self::get_environment(); child c = launch("cmd", "/c batch.bat", ctx); Should it be necessary to hardcode "cmd /c" like that? Shouldn't this all be taken care of by "boost::process::shell"? Frederick

2 2

[SPAM] Boost Library on Samsung A71(SM-A715F/DS) TLS handshake connection problem
by sean chang 10 Mar '20

10 Mar '20

Hi , Here comes look like a boost library connection problem on a mobile device. The SSL handshake connection problem failures happen on a new smart phone device: Samsung A71 with Android 10. Compare Devices: Pixel 3a (Android 10), Samsung A51(Android 10) or lower than Android 10 devices—> working great without problem We are design an SDK integrated Boost C++ Library with openssl for API calls, but not sure what happen on this mobile phone about boost library connection problem and reason, we are looking for solution or work around to fix this problem. Thanks a lot. below is the information what we get from boost debug. Tested Boost version: 1.67.0~1.71.0 Tested openssl: 1.0.2h and 1.1.1 Situation(1): The SSL connection is possible make connection wait for 30 sec, then we will receive system: 125 error code. attached Log file: 2020-03-10 21:02:10.794 32722-390/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][handshake][146]: Arthur: SSL 2020-03-10 21:02:10.794 32722-390/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][perform][249]: Arthur: SSL 2020-03-10 21:02:10.794 32722-390/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][do_connect][339]: Arthur: SSL 2020-03-10 21:02:10.794 32722-390/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][perform][258]: Arthur: SSL, error(2) 2020-03-10 21:02:10.794 32722-390/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][perform][298]: Arthur: SSL 2020-03-10 21:02:10.795 32722-390/com.keypasco.vaktensample D/vakten: Canceled 1 number of waiters 2020-03-10 21:02:10.795 32722-390/com.keypasco.vaktensample V/vakten: / 2020-03-10 21:02:10.795 32722-390/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][handshake][146]: Arthur: SSL 2020-03-10 21:02:10.795 32722-390/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][perform][249]: Arthur: SSL 2020-03-10 21:02:10.795 32722-390/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][do_connect][339]: Arthur: SSL 2020-03-10 21:02:10.795 32722-390/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][perform][258]: Arthur: SSL, error(2) 2020-03-10 21:02:10.795 32722-390/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][perform][304]: Arthur: SSL 2020-03-10 21:02:10.795 32722-390/com.keypasco.vaktensample V/vakten: + void kp::web::ClientConnection::handle_connect_timeout(const boost::system::error_code&) 2020-03-10 21:02:10.795 32722-390/com.keypasco.vaktensample D/vakten: Connect timeout aborted 2020-03-10 21:02:10.795 32722-390/com.keypasco.vaktensample V/vakten: / 2020-03-10 21:02:12.722 32722-32730/com.keypasco.vaktensample I/co.vaktensampl: Compiler allocated 4266KB to compile void android.view.ViewRootImpl.performTraversals() 2020-03-10 21:02:13.811 32722-390/com.keypasco.vaktensample V/vakten: + void kp::web::ClientConnection::handle_handshake_timeout(const boost::system::error_code&) 2020-03-10 21:02:13.811 32722-390/com.keypasco.vaktensample D/vakten: Handshake timed out 2020-03-10 21:02:13.813 32722-390/com.keypasco.vaktensample V/vakten: / 2020-03-10 21:02:13.814 32722-390/com.keypasco.vaktensample V/vakten: + void kp::web::ClientConnection::close() 2020-03-10 21:02:13.814 32722-390/com.keypasco.vaktensample V/vakten: + void kp::web::Socket::shutdown(boost::system::error_code&) 2020-03-10 21:02:13.814 32722-390/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][shutdown][153]: Arthur: SSL 2020-03-10 21:02:13.814 32722-390/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][perform][249]: Arthur: SSL 2020-03-10 21:02:13.814 32722-390/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][do_shutdown][345]: Arthur: SSL 2020-03-10 21:02:13.814 32722-390/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][perform][258]: Arthur: SSL, error(1) 2020-03-10 21:02:13.814 32722-390/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][perform][262]: Arthur: SSL 2020-03-10 21:02:13.814 32722-390/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][map_error_code][209]: Arthur: SSL 2020-03-10 21:02:13.814 32722-390/com.keypasco.vaktensample V/vakten: / 2020-03-10 21:02:13.814 32722-390/com.keypasco.vaktensample D/vakten: error:140E0197:lib(20):func(224):reason(407) 2020-03-10 21:02:13.815 32722-390/com.keypasco.vaktensample D/vakten: Socket.shutdown error asio.ssl error 2020-03-10 21:02:13.815 32722-390/com.keypasco.vaktensample V/vakten: + boost::asio::basic_socket<boost::asio::ip::tcp, boost::asio::executor>::lowest_layer_type& kp::web::Socket::lowest_layer() 2020-03-10 21:02:13.815 32722-390/com.keypasco.vaktensample V/vakten: / 2020-03-10 21:02:13.815 32722-390/com.keypasco.vaktensample V/vakten: + kp::web::Socket::~Socket() 2020-03-10 21:02:13.815 32722-390/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][~engine][66]: Arthur: SSL 2020-03-10 21:02:13.815 32722-390/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][~engine][74]: Arthur: SSL_free 2020-03-10 21:02:13.816 32722-390/com.keypasco.vaktensample V/vakten: / 2020-03-10 21:02:13.816 32722-390/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/impl/context.ipp][~context][394]: Arthur: SSL 2020-03-10 21:02:13.816 32722-390/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/impl/context.ipp][~context][428]: Arthur: SSL_CTX_free 2020-03-10 21:02:13.816 32722-390/com.keypasco.vaktensample V/vakten: / 2020-03-10 21:02:13.818 32722-390/com.keypasco.vaktensample V/vakten: + void kp::web::ClientConnection::invoke_handler(boost::exception_ptr) 2020-03-10 21:02:13.818 32722-390/com.keypasco.vaktensample V/vakten: + void kp::web::WebClientImpl::handle_connect(boost::exception_ptr) 2020-03-10 21:02:13.819 32722-390/com.keypasco.vaktensample V/vakten: | + void kp::web::WebClientImpl::invoke_handler(boost::exception_ptr) 2020-03-10 21:02:13.819 32722-390/com.keypasco.vaktensample V/vakten: | | + void kp::web::ClientConnection::close() 2020-03-10 21:02:13.819 32722-390/com.keypasco.vaktensample V/vakten: | | / 2020-03-10 21:02:13.819 32722-390/com.keypasco.vaktensample V/vakten: | / 2020-03-10 21:02:13.819 32722-390/com.keypasco.vaktensample V/vakten: / 2020-03-10 21:02:13.819 32722-390/com.keypasco.vaktensample V/vakten: / 2020-03-10 21:02:13.820 32722-390/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][map_error_code][209]: Arthur: SSL 2020-03-10 21:02:13.820 32722-390/com.keypasco.vaktensample V/vakten: + void kp::web::ClientConnection::handle_handshake(const boost::system::error_code&) 2020-03-10 21:02:13.820 32722-390/com.keypasco.vaktensample D/vakten: Canceled 0 number of waiters 2020-03-10 21:02:13.820 32722-390/com.keypasco.vaktensample E/vakten: system:125 2020-03-10 21:02:13.820 32722-390/com.keypasco.vaktensample V/vakten: + void kp::web::ClientConnection::close() 2020-03-10 21:02:13.821 32722-390/com.keypasco.vaktensample V/vakten: / 2020-03-10 21:02:13.822 32722-390/com.keypasco.vaktensample V/vakten: / 2020-03-10 21:02:13.823 32722-390/com.keypasco.vaktensample V/vakten: + void kp::web::ClientConnection::close() 2020-03-10 21:02:13.823 32722-390/com.keypasco.vaktensample V/vakten: / 2020-03-10 21:02:13.824 32722-390/com.keypasco.vaktensample V/vakten: + void kp::web::ClientConnection::invoke_handler(boost::exception_ptr) 2020-03-10 21:02:13.824 32722-390/com.keypasco.vaktensample V/vakten: / 2020-03-10 21:02:13.825 32722-390/com.keypasco.vaktensample V/vakten: + boost::asio::io_service& kp::web::WebClientImpl::get_io_service() 2020-03-10 21:02:13.825 32722-390/com.keypasco.vaktensample V/vakten: + boost::asio::io_service& kp::web::ClientConnection::get_io_service() 2020-03-10 21:02:13.825 32722-390/com.keypasco.vaktensample V/vakten: / 2020-03-10 21:02:13.825 32722-390/com.keypasco.vaktensample V/vakten: / 2020-03-10 21:02:13.827 32722-390/com.keypasco.vaktensample I/vakten: KspNetworkException: SSL Connect_timeout(30). 2020-03-10 21:02:13.830 32722-390/com.keypasco.vaktensample V/vakten: + kp::client_api::v5::AppClient::~AppClient() 2020-03-10 21:02:13.830 32722-390/com.keypasco.vaktensample V/vakten: / 2020-03-10 21:02:13.830 32722-390/com.keypasco.vaktensample V/vakten: + kp::client_api::ApiClient::~ApiClient() 2020-03-10 21:02:13.830 32722-390/com.keypasco.vaktensample V/vakten: / 2020-03-10 21:02:13.831 32722-390/com.keypasco.vaktensample V/vakten: + kp::web::WebClient::~WebClient() 2020-03-10 21:02:13.831 32722-390/com.keypasco.vaktensample V/vakten: / 2020-03-10 21:02:13.831 32722-390/com.keypasco.vaktensample V/vakten: + kp::web::WebClientImpl::~WebClientImpl() 2020-03-10 21:02:13.831 32722-390/com.keypasco.vaktensample V/vakten: / 2020-03-10 21:02:13.831 32722-390/com.keypasco.vaktensample V/vakten: + kp::web::ClientConnection::~ClientConnection() 2020-03-10 21:02:13.831 32722-390/com.keypasco.vaktensample V/vakten: + void kp::web::ClientConnection::close() 2020-03-10 21:02:13.832 32722-390/com.keypasco.vaktensample V/vakten: / 2020-03-10 21:02:13.832 32722-390/com.keypasco.vaktensample V/vakten: / 2020-03-10 21:02:13.842 32722-32722/com.keypasco.vaktensample D/GetTasksFragment: Task list: [] Situation(2) When a launched app been SSL connection success. Press power button and turn on again. then the boost library will happen connection problem with system 2 error code, it can be happen many times until boost re-initial. attached Log: 2020-03-09 18:09:53.309 11748-11800/com.keypasco.vaktensample V/vakten: + void kp::web::ClientConnection::handle_connect(const boost::system::error_code&) 2020-03-09 18:09:53.309 11748-11800/com.keypasco.vaktensample V/vakten: + kp::web::ProxySetting::Type kp::web::ProxySetting::get_type() const 2020-03-09 18:09:53.310 11748-11800/com.keypasco.vaktensample V/vakten: / 2020-03-09 18:09:53.310 11748-11800/com.keypasco.vaktensample V/vakten: + static boost::shared_ptr<kp::web::WebProxy> kp::web::WebProxy::create(kp::web::ProxySetting::Type) 2020-03-09 18:09:53.310 11748-11800/com.keypasco.vaktensample V/vakten: | + kp::web::NullProxy::NullProxy() 2020-03-09 18:09:53.310 11748-11800/com.keypasco.vaktensample V/vakten: | / 2020-03-09 18:09:53.310 11748-11800/com.keypasco.vaktensample V/vakten: / 2020-03-09 18:09:53.310 11748-11800/com.keypasco.vaktensample V/vakten: + boost::asio::ip::tcp::socket& kp::web::Socket::get_socket() 2020-03-09 18:09:53.310 11748-11800/com.keypasco.vaktensample V/vakten: / 2020-03-09 18:09:53.310 11748-11800/com.keypasco.vaktensample V/vakten: + virtual void kp::web::NullProxy::connect(boost::asio::ip::tcp::socket&, const kp::web::ProxySetting&, const kp::web::Uri&) 2020-03-09 18:09:53.310 11748-11800/com.keypasco.vaktensample V/vakten: / 2020-03-09 18:09:53.310 11748-11800/com.keypasco.vaktensample V/vakten: + bool kp::web::Socket::is_ssl_socket() const 2020-03-09 18:09:53.310 11748-11800/com.keypasco.vaktensample V/vakten: / 2020-03-09 18:09:53.310 11748-11800/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][handshake][146] 2020-03-09 18:09:53.310 11748-11800/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][perform][249] 2020-03-09 18:09:53.310 11748-11800/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][do_connect][339] 2020-03-09 18:09:53.311 11748-11800/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][perform][258]: Arthur: SSL, error(2) 2020-03-09 18:09:53.311 11748-11800/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][perform][298] 2020-03-09 18:09:53.311 11748-11800/com.keypasco.vaktensample D/vakten: Canceled 1 number of waiters 2020-03-09 18:09:53.311 11748-11800/com.keypasco.vaktensample V/vakten: / 2020-03-09 18:09:53.311 11748-11800/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][map_error_code][209] 2020-03-09 18:09:53.311 11748-11800/com.keypasco.vaktensample V/vakten: + void kp::web::ClientConnection::handle_handshake(const boost::system::error_code&) 2020-03-09 18:09:53.311 11748-11800/com.keypasco.vaktensample D/vakten: Canceled 1 number of waiters 2020-03-09 18:09:53.311 11748-11800/com.keypasco.vaktensample E/vakten: system:2 2020-03-09 18:09:53.311 11748-11800/com.keypasco.vaktensample V/vakten: + void kp::web::ClientConnection::close() 2020-03-09 18:09:53.311 11748-11800/com.keypasco.vaktensample V/vakten: | + void kp::web::Socket::shutdown(boost::system::error_code&) 2020-03-09 18:09:53.311 11748-11800/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][shutdown][153] 2020-03-09 18:09:53.311 11748-11800/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][perform][249] 2020-03-09 18:09:53.311 11748-11800/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][do_shutdown][345] 2020-03-09 18:09:53.311 11748-11800/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][perform][258]: Arthur: SSL, error(1) 2020-03-09 18:09:53.311 11748-11800/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][perform][262] 2020-03-09 18:09:53.311 11748-11800/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][map_error_code][209] 2020-03-09 18:09:53.312 11748-11800/com.keypasco.vaktensample V/vakten: | / 2020-03-09 18:09:53.312 11748-11800/com.keypasco.vaktensample D/vakten: | error:140E0197:lib(20):func(224):reason(407) 2020-03-09 18:09:53.312 11748-11800/com.keypasco.vaktensample D/vakten: | Socket.shutdown error asio.ssl error 2020-03-09 18:09:53.312 11748-11800/com.keypasco.vaktensample V/vakten: | + boost::asio::basic_socket<boost::asio::ip::tcp, boost::asio::executor>::lowest_layer_type& kp::web::Socket::lowest_layer() 2020-03-09 18:09:53.312 11748-11800/com.keypasco.vaktensample V/vakten: | / 2020-03-09 18:09:53.312 11748-11800/com.keypasco.vaktensample V/vakten: | + kp::web::Socket::~Socket() 2020-03-09 18:09:53.312 11748-11800/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][~engine][66]: Arthur: SSL 2020-03-09 18:09:53.312 11748-11800/com.keypasco.vaktensample D/Boost: [/home/arthur/project/boost_for_android/svn/vakten-lib/trunk/target/dependency/include/boost/asio/ssl/detail/impl/engine.ipp][~engine][74]: Arthur: SSL_free 2020-03-09 18:09:53.312 11748-11800/com.keypasco.vaktensample V/vakten: | /

1 0

Question about Boost::Interprocess::Allocators.
by Da Xu 09 Mar '20

09 Mar '20

Hi folks, I got a question about the boost::interprocess::allocators. I am a little confused as to when to use the standard shared memory allocator, and when to use node_allocator, or any of the other ones. What's the advantage and disadvantage of each? I read through the documentation, but it's not making a whole lot of sense. I am mainly using the allocators with the spsc_queue to transfer objects around, which may contain vectors floats or strings. One thing also confused me a little is that the non-standard shared memory allocators are all marked as not thread safe? I am not sure what does this mean. I assume these allocators will be interprocess safe? As in, I don't need to lock the shared memory to allocate memory, right? Maybe it means I can't share these allocators between threads in the same process? Any thoughts/tips would be greatly appreciated. Thank you. Da.

2 1

Boost.Test failing to compare std::basic_string<char8_t> strings
by Leo Carreon 09 Mar '20

09 Mar '20

Hi Boost.Users, I’m using Boost.Test from Boost 1.72.0 and I’m getting a failure when I perform the following test: auto string_1 = u8”value”s; auto string_2 = u8”value”s; BOOST_TEST(string_1 == string_2); However, the problem goes away when I change the test line to: BOOST_TEST((string_1 == string_2)); What is the reason why Boost.Test is failing without the double parentheses? Kind regards, Leo

2 3

[date-time] USE_DATE_TIME_PRE_1_33_FACET_IO to be removed in next release
by Jeff Garland 06 Mar '20

06 Mar '20

In case you've not checked the calendar (see below) it's 2020 and a the c++ world has moved on from the issue this macro solved. boost date-time also needs to move forward into the decade with a modernized all header code base . If you're dependent on this macro for any reason I'd like to hear about it. Thanks, Jeff using namespace boost::gregorian; date today = day_clock::local_day(); cout << today.year() << endl; //2020 ;)

1 0

uBlas and Google Summer of Code 2020
by David Bellot 06 Mar '20

06 Mar '20

Hi Boost community, I've added new projects for the Google Summer of Code 2020 for the Boost uBlas library (matrix computations, tensors and linear algebra). If you're a student and wish to candidate, please contact me as soon as possible. The list of projects is here: https://github.com/boostorg/wiki/wiki/Google-Summer-of-Code%3A-2020 Cheers, David

2 2

[mp11][mpl] Recurse over type list using mp11's mp_rest
by deb 06 Mar '20

06 Mar '20

Hello, I am currently learning about mp11 from the docs . While mpl had an iterator functionality to get an alias over a type in mp_list it seemed mp11's mp_rest could be used for a similar task. So I coded up a simple example of recursing over a type list based on some type check , but am quite lost trying to make it work . So a possible pseudo code for the above might be template<typename list> struct recurse{ using rest_of_list=mp_rest<list>; using type = typename std::conditional< mp_empty<rest_of_list>::value, base type here on empty list, typename std::conditional< some "loop" break condition, type on true condition, typename recurse< rest_of_list >::type >::type >::type; } Is this even possible or there exists some other method to do the same in mp11. Thanks. -- Sent from: http://boost.2283326.n4.nabble.com/Boost-Users-f2553780.html

3 5

yabs: Yet Another Build System, seeking input/micro-team member
by degski 03 Mar '20

03 Mar '20

Hi All, Recently, I have started to get more and more dis-enchanted with Windows. The OS is being dumbed down every step of the way, while the internal complexity keeps going up. The latest and the most fun break-down to date of Windows was last week, the story is long, but in the end in came down to not being able to open the system-settings in the W10-style settings. The W7-style settings are also available, but the API's are overlapping but neither is a super-set of the other, so no way to fix the settings, because the settings themselves are broken (had something to do with display-drivers), way to go MS. In the meanwhile W10 is sorted again, but the whole lot is just getting increasingly fragile, while Fedora is getting increasingly solid (no bt-headphone stuttering, while connected to wifi and look at that brightness/crispness of that Full HD screen I have never seen before under W10!), the latter not upping complexity (2'001 packages to download and install to get from F30 to F31, but that's not complexity). I want to move to Fedora, and for now I'm dual-booting. This involves dumping VS in favor of VSCode (which is flat-packed for Fedora and compadres and is also available on OSX, so there is potentially a large audience), no acceptable other options (other than the one(s) VSCode is based on) are available AFAIKS, gnome-builder seems to have different goals from VS and it appears to be early days. VSCode seems (to me) to be like the best thing since sliced-bread, iff you are writing Python or Rust (Prolog works nicely as well), but C++ is only partially great, the language server works very nicely, code completion, good, but the build-system, proposed, is cumbersome. I would like VSCode to work more like VS, but without the complexity, the endless clicking, drop-down boxes etc etc. It comes down to writing json-files, which is good, but on a per project basis. Having to do this on a per project basis is a problem (that's going backwards from using project-templates in VS, I now in VS can create a new project in 3 seconds flat, and every detailed setting (clang and vc) is set correctly and how **I** want it, and I am running "Hello World!" (the default main in the template) in total 10 secs, this very handy to try things out). I don't want to go backwards. Therefore, I would like to do this on a repo-basis (the only one I have), with, iff required, another json in the project-folder (in the parent repo-folder), i.e.: /repos/ /repos/repo.json /repos/project-one/ /repos/project-one/project.json /repos/project-two/ /repos/project-two/project.json /repos/ ... I (want to) use vcpkg. I structure my projects always the same, all build systems (to my purpose) are basically an over-shoot on the one hand and overly fiddly on the other hand. The task at hand, build the .cpp files in the root of the project folder into one binary. The include files are either in the vcpkg/installed/.../include folder or in a sub-include-folder in the project. Libraries to link are either in vcpkg/installed/.../lib, or vcpkg/installed/.../debug/lib. We are not talking rocket-science here, I presume that many people have simple needs like this/me, or that if building (adopting this structure) becomes easy enough people would adopt such a structure. I would like to have one json to rule them all, and one json to either over-ride the defaults, or to add to the defaults, depending on whether the setting is defined in the repo.json. The repo.json might well be layered itself, to accommodate the various compilers, and/or configuration. For the moment nlohman's json seems perfectly adequate for the job, and it's certainly easy to use (and seems to just use std::maps in a clever way, so it's easy to follow what's going on). It's all about merging, fusing, overlaying those json's as needed (gonna be entertaining, making it smart), and pass that on to some generic API for building. So a new compiler would mean to just add a json-section, or a json-file, fill that with appropriate data (possibly nothing, iff the default-defaults are good), and it should work. The current way VSCode is setup, means that this imaginary build-system can be easily and readily included/used in VSCode (with more json). Yes, just like the working name indicates YABS, it must be as simple as possible, but no simpler. Any input is appreciated, but please refrain from arguing that BS-X does this better (and exists) or BS-Y has a large crowd of followers (and is used for a long period of time), that's water under the bridge, I will pursue this, just to see how far one can get pushing these initial ideas further. As usual my write-ups are a bit messy, I am learning I'm slightly dyslexic, sorry for the endless comma's. Thanks in advance for any ideas submitted. I would not mind partnering with somebody else, ya'll have a nice day, degski -- @systemdeg "We value your privacy, click here!" Sod off! - degski "Anyone who believes that exponential growth can go on forever in a finite world is either a madman or an economist" - Kenneth E. Boulding "Growth for the sake of growth is the ideology of the cancer cell" - Edward P. Abbey

2 1

How to trim headers into a strict header-only subset
by state_of_the_art 03 Mar '20

03 Mar '20

Hello, I have used Boost Library a few years but recently I hava a new need. I know that some modules need to be built separately before use.But for my personal need,I need a strict header-only subset so that I can place the trimed boost headers folder in any project and simply build that project. Therefore I tried to use bcp,but the bcp copies some modules which need separately build. For example,run "./bcp --report coroutine2 fiber dependencies.html" and I see this html,there are some lines: …………………… boost/context/continuation_ucontext.hpp -> libs/context/src/continuation.cpp -> libs/context/src -> boost/context/segmented_stack.hpp -> boost/coroutine2/segmented_stack.hpp -> boost/coroutine2boost/context/continuation_winfib.hpp -> libs/context/src/continuation.cpp -> libs/context/src -> boost/context/segmented_stack.hpp -> boost/coroutine2/segmented_stack.hpp -> boost/coroutine2boost/context/detail/apply.hpp -> boost/fiber/type.hpp -> boost/fiberboost/context/detail/config.hpp -> boost/fiber/condition_variable.hpp -> boost/fiberboost/context/detail/disable_overload.hpp -> boost/coroutine2/detail/disable_overload.hpp -> boost/coroutine2/detail -> boost/coroutine2 …………………… Coroutine2 can be header-only used.But I know that Boost.Context need to be built separately via webpage getting_started/unix-variants …… I don't mind the size after triming but I want to make sure that trimed subset of modules can be used strictly header-only.Is there a better way or if my need can hardly be met? Thank you for your kindly help! Logan Smith 2020-03-03

1 0

Shared memory between Visual Studio build and MinGW build
by Da Xu 03 Mar '20

03 Mar '20

Hi folks, got a strange one here. I am trying to get two programs to communicate with each other on Windows 10 via shared memory. Both of them are using Boost 1.72, compiled from the same set of headers. I am only using the shared memory portion of boost. However, one is compiled with Visual studio 2019 community, and the other one is compiled with MinGW 64, g++ version 9.2.0. I have to use MinGW, because I am writing a plugin for another program, which only takes dlls compiled with MinGW. The program compiled with MinGW creates the shared memory and allocates several objects. Then I started the second program that was compiled with Visual Studio 2019. It was able to find and connect to the managed segment. When I am viewing the segment info from Visual Studio's debugger, everything looks ok. However, when I call get_free_memory(). It spits back 18446744073709551104, which is just bizarre. Then, when I tried to find_or_construct on the managed segment. It just hangs, apparently stuck in winapi::sleep_tick() with the following tracedll!boost::interprocess::winapi::sleep_tick() Line 1288 C++dll!boost::interprocess::ipcdetail::thread_sleep_tick() Line 187 C++dll!boost::interprocess::spin_wait::yield() Line 128 C++dll!boost::interprocess::ipcdetail::try_based_lock<boost::interprocess::ipcdetail::spin_mutex>(boost::interprocess::ipcdetail::spin_mutex & m) Line 71 C++dll!boost::interprocess::ipcdetail::spin_mutex::lock() Line 81 C++dll!boost::interprocess::ipcdetail::spin_recursive_mutex::lock() Line 95 C++dll!boost::interprocess::interprocess_recursive_mutex::lock() Line 165 C++dll!boost::interprocess::scoped_lock<boost::interprocess::interprocess_recursive_mutex>::scoped_lock<boost::interprocess::interprocess_recursive_mutex>(boost::interprocess::interprocess_recursive_mutex & m) Line 81 C++dll!boost::interprocess::segment_manager<char,boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family,boost::interprocess::offset_ptr<void,__int64,unsigned __int64,0>,0>,boost::interprocess::iset_index>::priv_generic_named_construct<char>(unsigned char type, const char * name, unsigned __int64 num, bool try2find, bool dothrow, boost::interprocess::ipcdetail::in_place_interface & table, boost::interprocess::iset_index<boost::interprocess::ipcdetail::index_config<char,boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family,boost::interprocess::offset_ptr<void,__int64,unsigned __int64,0>,0>>> & index, boost::interprocess::ipcdetail::bool_<1> is_intrusive) Line 1076 C++dll!boost::interprocess::segment_manager<char,boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family,boost::interprocess::offset_ptr<void,__int64,unsigned __int64,0>,0>,boost::interprocess::iset_index>::priv_generic_construct(const char * name, unsigned __int64 num, bool try2find, bool dothrow, boost::interprocess::ipcdetail::in_place_interface & table) Line 760 C++dll!boost::interprocess::segment_manager<char,boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family,boost::interprocess::offset_ptr<void,__int64,unsigned __int64,0>,0>,boost::interprocess::iset_index>::generic_construct<SharedMem_Info>(const char * name, unsigned __int64 num, bool try2find, bool dothrow, boost::interprocess::ipcdetail::in_place_interface & table) Line 705 C++dll!boost::interprocess::ipcdetail::named_proxy<boost::interprocess::segment_manager<char,boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family,boost::interprocess::offset_ptr<void,__int64,unsigned __int64,0>,0>,boost::interprocess::iset_index>,SharedMem_Info,0>::operator()<char const (&)[17],int,int,int,int,bool,boost::interprocess::allocator<void,boost::interprocess::segment_manager<char,boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family,boost::interprocess::offset_ptr<void,__int64,unsigned __int64,0>,0>,boost::interprocess::iset_index>> &>(const char[17] & <args_0>, int && <args_1>, int && <args_2>, int && <args_3>, int && <args_4>, bool && <args_5>, boost::interprocess::allocator<void,boost::interprocess::segment_manager<char,boost::interprocess::rbtree_best_fit<boost::interprocess::mutex_family,boost::interprocess::offset_ptr<void,__int64,unsigned __int64,0>,0>,boost::interprocess::iset_index>> & <args_6>) Line 131 C++ It looks like it the segment manager was unable to get a mutex lock on the memory? But I don't believe I put a mutex lock on the segment manager from the other end. Everything works just fine if I am doing shared memory between two programs compiled with visual studio. So, it feels like somewhere some how memory alignment is off? Anybody ran into a similar issue before? Any help would be greatly appreciated! Thank you!!

4 5

Download permissions off
by Forwarding 29 Feb '20

29 Feb '20

Cannot seem to download sources. A sampling of directories, e.g. https://dl.bintray.com/boostorg/release/1.72.0/source/, all yield the following when choosing one of the archives:Forbidden!This is a new development, download was OK yesterday morning.Thx.-Matthew

2 1

(SOLVED) Re: [Boost.Test] duplicate symbol '_main' (manual test registration)
by Andrew McFarlane 29 Feb '20

29 Feb '20

Hello all, I just wanted to let you know that I figured out my problem. It had nothing to do with Boost.Test and had everything to do with my Makefile. My Makefile was literally telling g++ to try and compile main.cpp twice and place the output in bin. - I had defined an implicit rule to compile all .cpp files to .o files, like so: $(ODIR_TEST)/%.o : $(SDIR_TEST)/%.cpp $(CC) $(CXXFLAGS) -c $< -o $@ - And silly me, I wrote the default rule as follows: $(OUTDIR)/$(PROG) : $(SDIR_TEST)/main.cpp $(TEST_OBJS) $(CC) $(CXXFLAGS) -o $@ $^ $(TEST_OBJS) is just a list of all .o files prefixed with ./bin/. As you can imagine, taking $(SDIR_TEST)/main.cpp out of the list of prerequisites completely fixed the issue. I was able to compile and run all 34 tests successfully from one executable. Hurray!! It feels good to have figured this out, especially because I was able to do so on my own, but also makes me feel quite silly. Oh well, now I know. My apologies for burdening your inboxes with my stupidity. - AJ

1 0

Re: [Boost-users] Boost-users Digest, Vol 5327, Issue 1
by Andrew McFarlane 29 Feb '20

29 Feb '20

Okay, I have almost completely fixed my problems. I just spent the past hour: - creating test case headers for each test translation unit (don't worry, I sped this up using a macro hehe) - inserting static test case method declarations privately in said headers - eliminating method redefinitions by toying with test translation unit #includes I am ALMOST there. Going to start a new issue, as my current problem is now vastly different from what is stated in the subject line. Consider the original problem for this issue SOLVED. Cheers! On Fri, Feb 28, 2020 at 9:04 PM <boost-users-request(a)lists.boost.org> wrote: > Send Boost-users mailing list submissions to > boost-users(a)lists.boost.org > > To subscribe or unsubscribe via the World Wide Web, visit > https://lists.boost.org/mailman/listinfo.cgi/boost-users > or, via email, send a message with subject or body 'help' to > boost-users-request(a)lists.boost.org > > You can reach the person managing the list at > boost-users-owner(a)lists.boost.org > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of Boost-users digest..." > > > Today's Topics: > > 1. [Boost.Test] linking with shared lib (cannot find main) > (Andrew McFarlane) > 2. Re: [Boost.Test] linking with shared lib (cannot find main) > (Andrew McFarlane) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Fri, 28 Feb 2020 18:50:38 -0800 > From: Andrew McFarlane <andrew.mcfarlane52(a)gmail.com> > To: Boost users list <boost-users(a)lists.boost.org> > Subject: [Boost-users] [Boost.Test] linking with shared lib (cannot > find main) > Message-ID: > < > CAG90r9S4rCVPXACn5o6zG9xZQe9oucr7zR6PYHKHqgdUGGJ1Bw(a)mail.gmail.com> > Content-Type: text/plain; charset="utf-8" > > Hi all, > > I have been using Boost.Test for about a month now. Big fan so far, except > for the atrocious compilation times, hence why I am moving toward using the > shared library. > > using b2 to build and install Boost.Test's libs was simple enough, though > after making the noted changes here: > > https://www.boost.org/doc/libs/1_72_0/libs/test/doc/html/boost_test/adv_sce… > > to customize the module's entry point, g++ cannot find the main executable: > > Undefined symbols for architecture x86_64: > > "_main", referenced from: > > implicit entry/start for main executable > > ld: symbol(s) not found for architecture x86_64 > > clang: error: linker command failed with exit code 1 (use -v to see > invocation) > > make: *** [Guest_T] Error 1 > > I tried digging through the docs for more information, but I came up short. > > For more context, I have written unit tests for each of my classes. For > example, if my classes were A, B, and C, I would have A_T.cpp, B_T.cpp, and > C_T.cpp for unit tests. > > - Should each of the unit tests have their own main() function? (I would > think not..) > > - If not, how do I instruct g++ to first compile main.cpp before attempting > to compile anything else? > > If you are curious, here are the contents of my Makefile: > > PROG := main > > CC := g++ > > SDIR := ../src > > PKG_DIRS := $(shell ls $(SDIR)) > > CXXFLAGS = -v -Wall -std=c++11 -I$(SDIR_TEST) \ > > $(addprefix -I$(SDIR)/,$(PKG_DIRS)) -I$(BOOST_ROOT) \ > > -L$(BOOST_LIBS) -Wl,-rpath,$(BOOST_LIBS) -lboost_unit_test_framework > > ODIR_TEST = ./bin > > SDIR_TEST = ./src > > OUTDIR = ./execs > > ODIR = ../sim/bin > > > TEST_EXEC_NAMES = $(notdir $(basename $(wildcard $(SDIR_TEST)/*.cpp))) > > > $(OUTDIR)/$(PROG) : $(SDIR_TEST)/main.cpp > > $(CC) $(CXXFLAGS) -o $@ $< > > > $(OUTDIR)/$(PROG) : $(TEST_EXEC_NAMES) > > $(CC) $(CXXFLAGS) -o $@ $^ > > > % : $(SDIR_TEST)/%.cpp > > $(CC) $(CXXFLAGS) -o $(OUTDIR)/$@ $^ > > >From what I can tell, g++ is failing to find the main the executable > because it is attempting to compile one of my unit test files first. This > may or may not be the case; either way, I would appreciate some help or > direction as to what I should read to learn more about this. > > Let me know if you need more info. > > Thanks in advance. > > - AJ >

1 0

[GSoC] Boost C++ and Slack channel
by Mateusz Loskot 27 Feb '20

27 Feb '20

Hi, I'm forwarding David's announcement copied below and available at https://lists.boost.org/Archives/boost/2020/02/248254.php You can join that Slack workspace at https://cppalliance.org/slack/ ML ------ Hi Boost community, we have a dedicated channel on Slack for all the discussions regarding the Google Summer of Code. Please join us on cpplang.slack.com on the channell #boost-gsoc. Cheers, David

1 0

[boost::regex] Build static library with ICU support on windows
by Eko palypse 27 Feb '20

27 Feb '20

I'm confused about the different post I've found on the web therefore would appreciate if someone could answer if it is possible to build a static regex library with ICU support on windows? Thank you Eren

2 2

Stieltjes polynomial
by N A 26 Feb '20

26 Feb '20

Hi, With regard to the article on Boost: Legendre-Stieltjes Polynomials - 1.66.0 | | | | Legendre-Stieltjes Polynomials - 1.66.0 | | | Can anyone help me to compute the stieltjes polynomials please? I'm coding in VBA and I'm looking for some recursive rules to calculate same. ThanksVick

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[GSoC] My piece of advice to students
by Mateusz Loskot 24 Feb '20

24 Feb '20

Dear Student, You are planning to participate in GSoC and develop some new features for the Boost libraries. Awesome! So, you want to introduce yourself to the community as soon as possible. Awesome! However, before posting your first question to the Boost mailing list, please, do read the official GSoC student guides [0]. All of it. [0] https://google.github.io/gsocguides/student/ I also recommend to read through other resources dedicated for students, especially this one from Google [1], one from a former student [2] as well as advice from Boost GSoC former student Louis Dionne [3]. [1] https://opensource.googleblog.com/2011/03/dos-and-donts-of-google-summer-of… [2] https://medium.com/@akshikawijesundara/google-summer-of-code-dos-and-do-not… [3] https://github.com/boostorg/wiki/wiki/Google-Summer-of-Code%3A-Advice-From-… Once you get through the general GSoC materials, it's a good idea to start browsing Boost resources, from intro [3] through netiquette [4] to wiki [5]. On [3] and [5] you will find links to past and current project ideas for Boost libraries. Browse it, read it, and learn what kind of projects Boost community develops during GSoC. Start thinking about what interests you, which Boost library, which project, what you'd like to develop as GSoC student. [4] https://www.boost.org/community/gsoc.html [5] https://www.boost.org/community/policy.html [6] https://github.com/boostorg/wiki/wiki Meanwhile, it's a good idea to "Make First Contact" [0]. Subscribe to the boost (developers) and boost-user or library-specific mailing list at https://lists.boost.org join Boost channels on Slack at https://cppalliance.org/slack/ and start discussing your participation, project ideas, etc. Although the student guides [0] use the phrase about "communicating directly with potential mentors", it does NOT mean exchanging private e-mails with mentors asking "Are you interested to mentor me?". GSoC does not work this way. In my opinion, the word "directly" means to interact directly with the community where, obviously, potential mentors are members too. The Boost organization and mentors will have chance to select students and projects they wish to mentor during the selection process - a secret, you can learn about it from GSoC guides for mentors [8]. Yes, the selection is a competitive process. [8] https://google.github.io/gsocguides/mentor/selecting-a-student Next, start discussing project of your interest, start asking questions, investigate ways to contribute to Boost, start working on competency tests Mind you, competency test is Boost way to verify minimum necessary skills. I personally think Boost should also ask for a bug fix [2] explains: "Some organizations make it a must for you to fix a bug in their code base before submitting a proposal but some do not. Your chances are always high if you can fix a bug in the code." Submitting a pull request with a small feature is also a good idea, something to discuss with mentors/maintainers of library of your interest Pull requests will allow you to gain hands-on experience with workflow of peer reviews, continuous communication, addressing problems, testing your solution, using the infrastructure, being exposed to stress of 'annoying' requests from maintainers to fix this, tweak that... :-) For example, it worked well for Boost.GIL (you can PRs at https://github.com/boostorg/gil) "you have to go early even if you go to hell" [2] GSoC IS hard work! Make sure to start early, to take a proactive stance, to do your homework before you start asking questions, to expect no babysitting. Imagine the GSoC runs back in times when there is no StackOverflow, no web archives, no web search,... There really is no excuse for not searching the web first nowadays. Even compilers can do that! https://arxiv.org/abs/1906.11456 "To grow in life, be willing to suffer" ~David Goggins Have a great time during GSoC and good luck! Best regards, -- Mateusz Loskot, http://mateusz.loskot.net

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