FindNextFile fails on 64-bit Windows?

Question

using C++Builder 2007, the FindFirstFile and FindNextFile functions doesn't seem to be able to find some files on 64-bit versions of Vista and XP. My test application is 32-bit.

If I use them to iterate through the folder C:\Windows\System32\Drivers they only find a handful of files although there are 185 when I issue a dir command in a command prompt. Using the same example code lists all files fine on a 32-bit version of XP.

Here is a small example program:

int main(int argc, char* argv[])
{
  HANDLE hFind;
  WIN32_FIND_DATA FindData;
  int ErrorCode;
  bool cont = true;

  cout << "FindFirst/Next demo." << endl << endl;

  hFind = FindFirstFile("*.*", &FindData);
  if(hFind == INVALID_HANDLE_VALUE)
  {
    ErrorCode = GetLastError();
    if (ErrorCode == ERROR_FILE_NOT_FOUND)
    {
      cout << "There are no files matching that path/mask\n" << endl;
    }
    else
    {
      cout << "FindFirstFile() returned error code " << ErrorCode << endl;
    }
    cont = false;
  }
  else
  {
    cout << FindData.cFileName << endl;
  }

  if (cont)
  {
    while (FindNextFile(hFind, &FindData))
    {
      cout << FindData.cFileName << endl;
    }

    ErrorCode = GetLastError();
    if (ErrorCode == ERROR_NO_MORE_FILES)
    {
      cout << endl << "All files logged." << endl;
    }
    else
    {
      cout << "FindNextFile() returned error code " << ErrorCode << endl;
    }

    if (!FindClose(hFind))
    {
      ErrorCode = GetLastError();
      cout << "FindClose() returned error code " << ErrorCode << endl;
    }
  }
  return 0;
}

Running it in the C:\Windows\System32\Drivers folder on 64-bit XP returns this:

C:\WINDOWS\system32\drivers>t:\Project1.exe
FindFirst/Next demo.

.
..
AsIO.sys
ASUSHWIO.SYS
hfile.txt
raspti.zip
stcp2v30.sys
truecrypt.sys

All files logged.

A dir command on the same system returns this:

C:\WINDOWS\system32\drivers>dir/p
 Volume in drive C has no label.
 Volume Serial Number is E8E1-0F1E

 Directory of C:\WINDOWS\system32\drivers

16-09-2008  23:12    <DIR>          .
16-09-2008  23:12    <DIR>          ..
17-02-2007  00:02            80.384 1394bus.sys
16-09-2008  23:12             9.453 a.txt
17-02-2007  00:02           322.560 acpi.sys
29-03-2006  14:00            18.432 acpiec.sys
24-03-2005  17:11           188.928 aec.sys
21-06-2008  15:07           291.840 afd.sys
29-03-2006  14:00            51.712 amdk8.sys
17-02-2007  00:03           111.104 arp1394.sys
08-05-2006  20:19             8.192 ASACPI.sys
29-03-2006  14:00            25.088 asyncmac.sys
17-02-2007  00:03           150.016 atapi.sys
17-02-2007  00:03           106.496 atmarpc.sys
29-03-2006  14:00            57.344 atmepvc.sys
17-02-2007  00:03            91.648 atmlane.sys
17-02-2007  00:03           569.856 atmuni.sys
24-03-2005  19:12             5.632 audstub.sys
29-03-2006  14:00             6.144 beep.sys
Press any key to continue . . .
etc.

I'm puzzled. What is the reason for this?

Brian

Answer 1

Is there redirection going on? See the remarks on Wow64DisableWow64FsRedirection http://msdn.microsoft.com/en-gb/library/aa365743.aspx