Algorithm for generating a unique ID in C++?

Question

What can be the best algorithm to generate a unique id in C++? The length ID should be a 32 bit unsigned integer.

Answer 1

There is little context, but if you are looking for a unique ID for objects within your application you can always use a singleton approach similar to

class IDGenerator {
   public:
      static IDGenerator * instance ();
      uint32_t next () { return _id++; }
   private:
      IDGenerator () : _id(0) {}

      static IDGenerator * only_copy;
      uint32_t _id;
}

IDGenerator *
IDGenerator::instance () {
   if (!only_copy) {
      only_copy = new IDGenerator();
   }
   return only_copy;
}

And now you can get a unique ID at any time by doing:

IDGenerator::instance()->next ()