C / C++ / MFC

OnStart()
{
     .
     .
     .
     // Set resolution to the minimum supported by the system
     TIMECAPS tc;
     timeGetDevCaps(&tc, sizeof(TIMECAPS));
     DWORD resolution = min(max(tc.wPeriodMin, 0), tc.wPeriodMax);
     timeBeginPeriod(resolution);     

    // create the timer
    timeSetEvent(iS,resolution,TimerFunction,(DWORD)this,TIME_PERIODIC);


void CTimerDlg::MMTimerHandler(UINT nIDEvent)
{
	//decrement the count
	iS --;
	//format and display the count
	m_timer2.Display(iS,iM,iH,iD,(CString)m_strTimer2="%D:%H:%M:%S");		
}


void CALLBACK TimerFunction(UINT wTimerID, UINT msg, DWORD dwUser, DWORD dw1, DWORD dw2)
{
    // This is used only to call MMTimerHandler
    // Typically, this function is static member of CTimersDlg
    CTimerDlg* obj = (CTimerDlg*) dwUser;
    obj->MMTimerHandler(wTimerID);

}

void Log()
{
	FILE *log;
	if((log = fopen("C:\\foo.log","a+t")) == NULL)
		return;

	
         SYSTEMTIME systime;
	GetSystemTime(&systime);

        
         // log time and date in european or at least german format like 1.10.2001 20:00
	char text[128];
	sprintf(text,"%s.%s.%s\t%s:%s",systime.wDay,systime.wMonth,systime.wYear,systime.wHour,systime.wMinute);

         
         // should write "text" into logfile, but crashes at "fwrite" :confused:
	size_t len = strlen(text);
	fwrite(text,sizeof(char),len,log);
	fclose(log);
}