Multithreaded file writer in C++
mul·ti·thread·ing A technique by which a single set of code can be used by several processors at different stages of execution. The class lock_guard is a mutex wrapper that provides a convenient RAII-style mechanism for owning a mutex or several mutexes (since C++17) for the duration of a scoped block. When a lock_guard object is created, it attempts to take ownership of the mutex it is given. When control leaves the scope in which the lock_guard object was created, the lock_guard is destructed and the mutex is released. If several mutexes are given, deadlock avoidance algorithm is used as if by std::lock . (since C++17) The lock_guard class is non-copyable. #include "stdafx.h" #include <mutex> CWinApp theApp; using namespace std; const int size_ = 100; //thread array size std::mutex mymutex; void printRailLock(int id) { printf("#ID :%d", id); lock_guard<std::mutex> lk(mymutex); // <- this is the lock CStdioFile lastLog;