void f4(){
//several shared_ptr objects can have the same pointer.
boost::shared_ptr<Investment> pInv1(createInvestment());
boost::shared_ptr<Investment> pInv2(pInv1);
//If every shared_ptr objects are freed, then the pointer
//that they have also freed.
}
void f3(){
std::cout << "f3" << std::endl;
//several auto_ptr cannot contain the same pointer.
//If you copy auto_ptr, then the source becomes null pointer and
//the destination can contain the pointer.
Investment* pInv1 = createInvestment();
std::auto_ptr<Investment> pInv2(pInv1);
std::auto_ptr<Investment> pInv3(pInv2);
}
//an example of auto_ptr
void f2(){
std::cout << "f2" << std::endl;
try {
//If you pass a pointer to auto_ptr,
//auto_ptr frees it when the control flow leaves the scope.
std::auto_ptr<Investment> pInv(createInvestment());
throw 1;
} catch (...) {
std::cout << "catch" << std::endl;
}
}
// an example of memory leak
void f1(){
std::cout << "f1" << std::endl;
try {
Investment *pInv = createInvestment();
//If some one write code that can throws error,
//destructor of Investment may not be called.
throw 1;
delete pInv;
} catch(...) {
std::cout << "catch" << std::endl;
}
}
Investment* return_row_ptr()
{
std::auto_ptr<Investment> pInv(createInvestment());
return pInv.get();
}
std::auto_ptr<Investment> return_auto_ptr()
{
std::auto_ptr<Investment> pInv(createInvestment());
return pInv;
}
