boost

问题 I've been trying to write a client-server application using boost::asio, overall the application works great but I've stumbled over a problem regarding the data provided by 'WriteHandler' ( async_write function) when the connoction (between client <> server) is droped by a firewalll or by manualy disabling a newtwork card. Here is the code snippet: void write(const CommunicatorMessage & msg, std::function<void(bool)> writeCallback) { io_service.dispatch( [this, msg, writeCallback]() { boost:

问题 I am using boost 1.73.0, and am trying to use circular_buffer together with manage_mapped_file to store strings in a circular buffer persisted on disk. I do the following to create/open the circular_buffer: boost::interprocess::managed_mapped_file mmf(boost::interprocess::open_or_create, "./circ_buffer.bin", 10u << 10); typedef boost::interprocess::allocator<std::string, boost::interprocess::managed_mapped_file::segment_manager> string_allocator; typedef boost::circular_buffer<std::string,

问题 I'm using BoostPython for embedding Python in my C++ project but I don't understand all stuffs about Python, especially the namespace system. Actually, I used this code: byte_code = Py_CompileString(filedata, filename, Py_file_input); // [...] PyObject* res = NULL; PyObject* main_module = PyImport_AddModule("__main__"); PyObject* global_dict = PyModule_GetDict(main_module); PyObject* local_dict = PyDict_New(); py::object local_namespace(py::handle<>(py::borrowed(local_dict))); // Set a user

问题 Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers. Want to improve this question? Update the question so it's on-topic for Stack Overflow. Closed 7 years ago . Improve this question how i can compile boost under linux without write in system folders. I need to get headers files and shared libraries of boost in one my specific folder. 回答1: You don't need to be root to compile Boost on Linux. Moreover, many Boost libraries are header only so no

问题 As like the description on Boost.Spirit, the only difference between lexeme and no_skip is the pre_skip. But after some test, I'm still confusing about the exactly meaning for pre_skip. So what kind of condition will make a difference, maybe a example can help me understand it much better. Thanks! 回答1: Pre-skip ignores whitespace at the start of the expression. Contrasting: Live On Coliru #include <boost/spirit/include/qi.hpp> namespace qi = boost::spirit::qi; static std::string const input =

问题 I'm having trouble with boost::variant (using boost 1.67.0). When my template parameter list includes both bool and std::string , any variant objects which should be treated as string, seem to be implicitly bound to bool instead. For example: using Varval = boost::variant<bool, std::string>; void main() { std::vector<Varval> vect{ true, false, "Hello_World" }; std::cout << "[ "; for (const auto &v : vect) std::cout << v << " "; std::cout << "]\n"; } Outputs: [ 1 0 1 ] whereas if I change

问题 I am new with boost and xml and I am trying to scan an xml file and save some specific values. I read this article and my question is: if the xml contains several <sked> , how do I iterate both of them? maybe BOOST_FOREACH () BOOST_FOREACH () // nested loop lets say the given xml file as follow (the purpose is to save both IDs): <?xml version="1.0"? encoding="utf-8"?> <arrayOfSked> <sked> <ID> 1 </ID> <version>2</version> <flight> <carrier>BA</carrier> <number>4001</number> <precision>0.1<

问题 Using boost::chrono::steady_clock or std::chrono::steady_clock is suppose to guarantee that physical time is always monotonic and is not affected by date time changes in the system. Here is my question, if I have two processes that need to be immune to system date time changes, is it enough to exchange just the time_since_epoch ? In other words, the time interpretation of the two processes to the same time since epoch will be the same? Specifically I need to answer this question for Windows

问题 "A": "1" "A.B": "2" "A.C": "3" How to get the value of A.B if i iterate through the ptree it works. if i try to get value of pt.get_child("A\.B").get_value<std::string>() . i get the following exception terminate called after throwing an instance of boost::exception_detail::clone_impl<boost::exception_detail::error_info_injector<boost::property_tree::ptree_bad_path> >' what(): No such node please find the complete code below #include <boost/property_tree/ptree.hpp> #include <boost/property

问题 "A": "1" "A.B": "2" "A.C": "3" How to get the value of A.B if i iterate through the ptree it works. if i try to get value of pt.get_child("A\.B").get_value<std::string>() . i get the following exception terminate called after throwing an instance of boost::exception_detail::clone_impl<boost::exception_detail::error_info_injector<boost::property_tree::ptree_bad_path> >' what(): No such node please find the complete code below #include <boost/property_tree/ptree.hpp> #include <boost/property