Pointer to end of file C++

Question

C++ / C#

Hello.
Can't get end of file pointer.
Tried to do like this:

std::fstream f;
f.open("test.txt");
std::cout<<*f.ate;

For, as far as I know, std::ios::ate throws to the end of the file. Perhaps I'm wrong.
Please, tell me how to display a pointer to the end of the file, preferably using fstring?

Answer 1

It is not very clear how the pointer to the end of the file should look like. You want to read the last n bytes then you need to do
const int needed_bytes = 10;
f.seek(0, is.end);
int length = f.tellg();
f.seek(0, length - needed_bytes);
f.read ...
In general, a file is represented by a file descriptor, and when a file is opened, it is not completely transferred to RAM, so a const char* type pointer to some place in the file cannot be obtained without doing the operation described above. mmap exception, but that's beyond the scope of your question