Write allocated memory to disk

Question

I have an allocated memory and I want to write it to a file. How can I do that in C++ 20?

I know I could do the following sequence, just like in C. However, in C++ there is the std::filesystem , can't I do that with it?

• CreateFile
• VirtualAlloc
• memcpy
• WriteFile
• VirtualFree
• CloseHandle

auto* const data = VirtualAlloc(nullptr, 0x1000, MEM_COMMIT | MEM_RESERVE, PAGE_EXECUTE_READWRITE);

if (!data)
    return 0;
    
memcpy(...);

if (data)
    VirtualFree(data, 0, MEM_RELEASE);

Answer 1

Here is the tried and true method for writing memory to a file:

// Open your output_file as binary
static const size_t DATA_CAPACITY = 0x1000;
output_file.write(data, DATA_CAPACITY);

This is known as block writing to a binary file (or a file in binary mode).