IE Cache的一个问题

Question

char szBuffer[255];
if(!CreateUrlCacheEntry("http://www.sina.com.cn/",20,".exe",szBuffer,0))
{
printf("CreateUrlCacheEntry Error With Code %d\n",GetLastError());
return;
}
HANDLE hFile =CreateFile(szBuffer,
GENERIC_READ,              // open for reading 
                FILE_SHARE_READ,           // share for reading 
                NULL,                      // no security 
                OPEN_EXISTING,             // existing file only 
                FILE_ATTRIBUTE_NORMAL,     // normal file 
                NULL);                     // no attr. template 
if(GetLastError()!=0)
{

printf("Can't Read File\n");
return;
} //开始往缓存文件中写数据
char buffer[20];
strcpy(buffer,"12132132131");
DWORD dwBytesWrite;
if(!WriteFile(hFile,buffer,20,&dwBytesWrite,NULL))
{
printf("Can't Write File %d\n",GetLastError());
return;
} FILETIME ft;
    SYSTEMTIME st;
    BOOL f;    GetSystemTime(&st);              // gets current time
    SystemTimeToFileTime(&st, &ft);  // converts to file time format
CommitUrlCacheEntry("www.sina.com.cn",szBuffer,ft,ft,NORMAL_CACHE_ENTRY,NULL,
0,NULL,0);