#pragma region Includes
#include <stdio.h>
#include <windows.h>
#pragma endregion
#define MAP_PREFIX          L"Local\\"
#define MAP_NAME            L"SampleMap"
#define FULL_MAP_NAME       MAP_PREFIX MAP_NAME

// Max size of the file mapping object.
#define MAP_SIZE            65536

// File offset where the view is to begin.
#define VIEW_OFFSET         0

// The number of bytes of a file mapping to map to the view. All bytes of the
// view must be within the maximum size of the file mapping object (MAP_SIZE).
// If VIEW_SIZE is 0, the mapping extends from the offset (VIEW_OFFSET) to 
// the end of the file mapping.
#define VIEW_SIZE           1024

// Unicode string message to be written to the mapped view. Its size in byte
// must be less than the view size (VIEW_SIZE).
#define MESSAGE             L"Message from the first process."

int wmain(int argc, wchar_t* argv[])
{
    HANDLE hMapFile = NULL;
    PVOID pView = NULL;

    // Create the file mapping object.
    hMapFile = CreateFileMapping(
        INVALID_HANDLE_VALUE,   // Use paging file - shared memory
        NULL,                   // Default security attributes
        PAGE_READWRITE,         // Allow read and write access
        0,                      // High-order DWORD of file mapping max size
        MAP_SIZE,               // Low-order DWORD of file mapping max size
        FULL_MAP_NAME           // Name of the file mapping object
        );
    if (hMapFile == NULL)
    {
        wprintf(L"CreateFileMapping failed w/err 0x%08lx\n", GetLastError());
        goto Cleanup;
    }
    wprintf(L"The file mapping (%s) is created\n", FULL_MAP_NAME);

    // Map a view of the file mapping into the address space of the current
    // process.
    pView = MapViewOfFile(
        hMapFile,               // Handle of the map object
        FILE_MAP_ALL_ACCESS,    // Read and write access
        0,                      // High-order DWORD of the file offset
        VIEW_OFFSET,            // Low-order DWORD of the file offset
        VIEW_SIZE               // The number of bytes to map to view
        );
    if (pView == NULL)
    {
        wprintf(L"MapViewOfFile failed w/err 0x%08lx\n", GetLastError());
        goto Cleanup;
    }
    wprintf(L"The file view is mapped\n");

    // Prepare a message to be written to the view.
    PWSTR pszMessage = MESSAGE;
    DWORD cbMessage = (wcslen(pszMessage) + 1) * sizeof(*pszMessage);

    // Write the message to the view.
    memcpy_s(pView, VIEW_SIZE, pszMessage, cbMessage);

    wprintf(L"This message is written to the view:\n\"%s\"\n",
        pszMessage);

    // Wait to clean up resources and stop the process.
    wprintf(L"Press ENTER to clean up resources and quit");
    getchar();

Cleanup:

    if (hMapFile)
    {
        if (pView)
        {
            // Unmap the file view.
            UnmapViewOfFile(pView);
            pView = NULL;
        }
        // Close the file mapping object.
        CloseHandle(hMapFile);
        hMapFile = NULL;
    }

    return 0;
}