查找一个进程

DWORD  CUpdateDlg::FindAppProcessID(CString &str)
{
 HANDLE handle=::CreateToolhelp32Snapshot(TH32CS_SNAPALL,0);
 PROCESSENTRY32 Info;
 Info.dwSize = sizeof(PROCESSENTRY32);
 if(::Process32First(handle,&Info))
 {
  do{
   CString ss=Info.szExeFile;
   if(!ss.CompareNoCase(str))
   {
    ::CloseHandle(handle);
    return Info.th32ProcessID;
   }
  }
  while(::Process32Next(handle,&Info)); 
  ::CloseHandle(handle);
 }
 return -1;
}