一个小函数，ShowErrMsg

void ShowErrMsg()
{
TCHAR szBuf[80];
LPVOID lpMsgBuf;
DWORD dw = GetLastError();

FormatMessage(
FORMAT_MESSAGE_ALLOCATE_BUFFER |
FORMAT_MESSAGE_FROM_SYSTEM,
NULL,
dw,
MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
(LPTSTR) &lpMsgBuf,
0, NULL );

MessageBox(NULL, lpMsgBuf, "系统错误", MB_OK|MB_ICONSTOP);

LocalFree(lpMsgBuf);
}