How to display the result of the work of WinAPI functions?

Question

C++ / C#

Let's say I read the contents of a file using ReadFile and store the result in a char buffer[100] variable, as in the example:

#include "windows.h"
#include <iostream>
#include <fcntl.h>
#include <io.h>

using namespace std;

int WINAPI WinMain(HINSTANCE hInstance,
  HINSTANCE hPrevInstance,
  LPSTR lpCmdLine,
  int nCmdShow)
{
  setlocale(LC_ALL, "Russian");
  char buffer[100];
  HANDLE file;
  bool isSucceed;
  LPWIN32_FIND_DATA find = 0;
  file = FindFirstFile(L"C:\\Users\\User\\Desktop\\LabOS_0\\Debug\\myfile.txt", find);
  if (file != INVALID_HANDLE_VALUE) {
    FindClose(file);
    isSucceed = ReadFile(file, buffer, 10, 0, 0);
  }

  for (int i = 0; i < 10; i++) {
    printf("%c", buffer[i]);
  }
  system("pause");
  return 0;
}

Why is the result not displayed in the console and how to do it in general?

Answer 1

your mistakes.
1. These are different descriptors.
FindFirstFile gives a handle to find files.
And ReadFile requires a file handle, which can be obtained via CreateFile.
2. The second parameter of FindFirstFile cannot be NULL. This is a pointer to WIN32_FILE_DATA, into which the function will throw information about the found files.
3. If you do not search by mask and you definitely want to open a file, why would you need FindFirstFile? Wield CreateFile immediately.
4. You have connected a couple of unnecessary headers.
5. I don't recommend writing 0 instead of a NULL pointer.
6. In ReadFile, the last two parameters cannot be NULL at the same time: the first one is for synchronous reading, the second one is for asynchronous.
In general, "smoke the mana." Fortunately, M$ has good ones.