Category : instance

Is the static memory section alignas(alignof(T)) char bytes[sizeof(T)] suitable to hold an instance of T during its lifetime by calling std::construct_at(bytes, …) / std::destroy_at(bytes)? My instincts say, yeah, the alignment and size requirements are guaranteed, so reinterpret_cast<T*>(bytes) is a valid pointer to a completely valid instance of type T. Am I missing something? Source: Windows ..

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In my program I have 6 classes : Environment, Animal, Ant, Soldier, Worker, Termite. Soldier + Worker inherits from Ant who itself inherits from Animal. Termite also inherits from Animal. In Environment, I have a vector of Animal. The problem is that I want to count the number of instances for each subclasses of Animal ..

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After create the server by openstack server create –image ws2k16 …, the result which show the adminPass field’s value isn’t correct, can’t login the windows server with that value. How to define the Administrator’s password by openstack server create, I had try –property admin_pass=123 or –user-data config_file parameter, but they can’t work. Maybe I define ..

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I´m slightly going mad… I want to use the DFRobotDFPlayerMini-Library in my Code. I structured my code in in a config.h-File for all common parameters and libs, several include-Files which should play mp3-files (here "comets"), and a main.cpp. Without the DFRobotDFPlayerMini option everything works fine. With it, compiler drops the failure "comets.cpp:61: undefined reference to ..

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I wrote the following class: class JobsList { public: class JobEntry { public: pid_t pid, jid; string cmd; time_t in_time; bool stopped; JobEntry(int pid, int jid, string &cmd, bool stopped); // TODO: Add your data members bool operator<(JobEntry &tmp) const { return jid<tmp.jid; } }; std::list<JobEntry> jobs; // TODO: Add your data members public: JobsList(); ..

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I’m also developing a tool that requires downloading one images to multiple device in a single process, but I heard that it seems that this is very difficult so not recommend. (My question is very similar to the previous one: Multiple instance of a dll in c++) However, I heard that each instance can be ..

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