Re: [Info-mtools] Inconsistent results between kernel vfat and mtools

[G.W. Haywood]

Hi there,

On Tue, 21 Nov 2023, Alexander Huemer wrote:

> I am observing inconsistent results between the kernel vfat
> implementation and mtools.
> The image file I am using is [1].
> Here is a simple procedure that shows what I am experiencing.
>
> Download the image. For simplicity that'll be called 'image.img' below.
>
> mkdir -p ~/tmp/unpack
> cd ~/tmp/unpack
> mcopy -a ~/image.img -a :: .
> sudo mount -t vfat ~/image.img /mnt
> diff -u <(md5sum *) <(cd /mnt; md5sum *)
>
> This is the result I am getting:
>
> --- /dev/fd/63  2023-11-21 07:21:10.930270864 +0000
> +++ /dev/fd/62  2023-11-21 07:21:10.930270864 +0000
> @@ -1,7 +1,7 @@
> -04ab6b3bd6f6689fe102a3531d15e8b1  003290.DSL
> -50bb89afd3ddb2d7fe62946ee0d780f3  013179.dsl
> -14c3e2c6c7c69d69c60e8a43b9c11ae1  023193.dsl
> +b16167d015a5a427088eb0200a5ba051  003290.DSL
> +00cd9c5a6948e029b310615b0fb074c2  013179.dsl
> +b42bd0a7f6cf5a81da57a6008436e5fa  023193.dsl
> fe80900bee88c24fa11089a9ababcf5e  CSCMCNME.CMD
> -9c21964c22e263063f638630e66560eb  MAINTRK.DIA
> +c94fc15f7efd09966c8bbc7ced0bab9d  MAINTRK.DIA
> e07b8d18af7fe075c74a220d3a7cda30  MRNLEV.ECN
> 428978ce5c2775926a4a1743b7af602e  VOLUME.LAB
>
> I believe that the results yielded by vfat are correct and the results
> yielded by mtools are incorrect.
>
> Does the image file have some unusual properties that push mtools to
> undesired behavior? User error?

First things first, which version of mtools are you using?

Here it's

8<----------------------------------------------------------------------
$ mtools -V
mtools (GNU mtools) 4.0.43
configured with the following options: enable-xdf disable-vold disable-new-vold disable-debug enable-raw-term 
8<----------------------------------------------------------------------

Second, something does seem odd, but not quite that... :/

Here, mcopy seems to have no trouble, but mdir does:

8<----------------------------------------------------------------------
$ mdir -i IBM_3174_DSL_FC9021_N52.0.img
 Volume in drive : has no label
Directory for ::/

No files
                            656 896 bytes free

$ mount -o loop IBM_3174_DSL_FC9021_N52.0.img /floppy
$ mkdir content
$ mcopy -i IBM_3174_DSL_FC9021_N52.0.img :: ./content
$ md5sum content/* /floppy/* | sort
00cd9c5a6948e029b310615b0fb074c2  content/013179.dsl
00cd9c5a6948e029b310615b0fb074c2  /floppy/013179.dsl
428978ce5c2775926a4a1743b7af602e  content/VOLUME.LAB
428978ce5c2775926a4a1743b7af602e  /floppy/VOLUME.LAB
b16167d015a5a427088eb0200a5ba051  content/003290.DSL
b16167d015a5a427088eb0200a5ba051  /floppy/003290.DSL
b42bd0a7f6cf5a81da57a6008436e5fa  content/023193.dsl
b42bd0a7f6cf5a81da57a6008436e5fa  /floppy/023193.dsl
c94fc15f7efd09966c8bbc7ced0bab9d  content/MAINTRK.DIA
c94fc15f7efd09966c8bbc7ced0bab9d  /floppy/MAINTRK.DIA
e07b8d18af7fe075c74a220d3a7cda30  content/MRNLEV.ECN
e07b8d18af7fe075c74a220d3a7cda30  /floppy/MRNLEV.ECN
fe80900bee88c24fa11089a9ababcf5e  content/CSCMCNME.CMD
fe80900bee88c24fa11089a9ababcf5e  /floppy/CSCMCNME.CMD
8<----------------------------------------------------------------------

HTH

--

73,
Ged.