c++ - Threading In Classes -


i creating asynchronous class logs strings file. should creating thread within class itself? thinking start function

void async_log::start (void) {   std::thread thread_log(     [&]()     {       std::ofstream fout;       fout.open(filename);       while(true)       {         if(q.size())         {           std::lock_guard<std::mutex> lock(m);           fout << q.front() <<  "\t @ time: " << std::clock() << std::endl;           q.pop();         }       }       fout.close();     }); }

or better leave threading main. first concern if threading unique (so if instantiate class 2 times 2 different files thread_log on written or have conflict).

there nothing wrong have dedicated thread in class, want note several things:

  1. inside thread implement busy waiting log messages. redundant , expensive! thread consumes cpu when there no messages in queue. need blocking queue there, block on pop() method. can find implementation of blocking queue c++ here or here.

  2. there need provide possibilty terminate logging thread. can eigher having 'terminate' variable check in loop, or sending special 'poison pill' message logger.


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