How to write a pointer to std::cerr?

Question

Given:

MY_CLASS* ptr = MY_CLASS::GetSomeInstance();

What is the correct way to output ptr to std::cerr, so I can log its value? Note I don't want to write the class, just the address.

Answer 1

operator<< is overloaded to take a const void*, so you can simply insert the pointer into the stream:

std::cerr << ptr;

The exception is that if the pointer is a const char*, it will be interpreted as a pointer to a C string. To print the pointer, you need to cast it explicitly to a const void*:

std::cerr << static_cast<const void*>(ptr);