C++智能指针之auto_ptr

Deprecated in C++ 11，因为Transfer of ownership。比如作为函数参数传递时，会丧失所有权。

• get() 获取原始指针
• release() 释放auto_ptr并返回原始指针
• reset(X*) 释放对象并为auto_ptr设置新值
• operator* 解引用对象
• operator-> 解引用对象成员
• operator= 拷贝并转移所有权

#include <memory>

struct S {
  int i;
};

int main() {
  std::auto_ptr<int> p1(new int);
  *p1.get() = 1;

  std::auto_ptr<int> p2(p1);
  // p1 is now null-pointer auto_ptr

  std::auto_ptr<int> p3 = p2;
  // p2 is now null-pointer auto_ptr

  p3.reset(new int);
  *p3 = 2;

  int* pi = p3.release();
  // p3 is now null-pointer auto_ptr

  delete pi;

  std::auto_ptr<S> ps(new S);
  ps->i = 3;

  return 0;
}