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Sample DOSFS disk image file for testing

Started by John Speth June 16, 2008
Hi Everybody-

I downloaded and built Lewin Edwards' DOSFS package.  It builds without a 
flaw.  I would love to get up and running quickly for desktop testing but 
the disk image file is missing from the package and that requires me to 
build my own.

I'm very unknowledgeable about FAT file systems.  That fact makes it 
difficult for me to create one from scratch.

Would anyone have a sample FAT32 diska image file that would work with DOSFS 
for local desktop testing?

I'd ask Lewin himself but he warns emphatically to not bother him with DOSFS 
questions.  (Lewin, can you make an exception?)

Thanks,

JJS


On Jun 16, 6:25=A0pm, "John Speth" <johnsp...@yahoo.com> wrote:
> Hi Everybody- > > I downloaded and built Lewin Edwards' DOSFS package. =A0It builds without =
a
> flaw. =A0I would love to get up and running quickly for desktop testing bu=
t
> the disk image file is missing from the package and that requires me to > build my own. > > I'm very unknowledgeable about FAT file systems. =A0That fact makes it > difficult for me to create one from scratch. > > Would anyone have a sample FAT32 diska image file that would work with DOS=
FS
> for local desktop testing?
Just format a USB thumb drive with the "/FS:FAT32" option from the command line. No problem so long as it's over 32MB in size and less than 2GB. Or do the same for a hard disk partition. Note that you cannot format a floppy FAT32, since it's not possible to put enough clusters on a floppy to get past the 65536 cluster threshold so that it will be detected as a FAT32 volume.
On Jun 16, 7:25 pm, "John Speth" <johnsp...@yahoo.com> wrote:

> Would anyone have a sample FAT32 diska image file that would work with DOSFS > for local desktop testing? > I'd ask Lewin himself but he warns emphatically to not bother him with DOSFS
What I actually say is that you can ask all you want, but I don't guarantee a response, and furthermore if I do respond and it involves a bugfix, then the bugfix is not your private property, it is added to the public source tree. Anyway - There is a 1GB FAT32 disk image at <http://www.larwe.com/temp/ 1gb_fat32.zip>. It is about a 5.5MB download; unused sectors were zeroed before imaging.
On Jun 16, 9:37 pm, "robertwess...@yahoo.com"
<robertwess...@yahoo.com> wrote:
> On Jun 16, 6:25 pm, "John Speth" <johnsp...@yahoo.com> wrote: > > > Hi Everybody- > > > I downloaded and built Lewin Edwards' DOSFS package. It builds without a > > flaw. I would love to get up and running quickly for desktop testing but > > the disk image file is missing from the package and that requires me to > > build my own. > > > I'm very unknowledgeable about FAT file systems. That fact makes it > > difficult for me to create one from scratch. > > > Would anyone have a sample FAT32 diska image file that would work with DOSFS > > for local desktop testing? > > Just format a USB thumb drive with the "/FS:FAT32" option from the > command line. No problem so long as it's over 32MB in size and less > than 2GB. > > Or do the same for a hard disk partition. Note that you cannot format > a floppy FAT32, since it's not possible to put enough clusters on a > floppy to get past the 65536 cluster threshold so that it will be > detected as a FAT32 volume.
Um, sorry if I'm missing something, but why "less than 2GB" ? Isn't FAT32 good for many orders more than 2GB ? Thanks, Best Regards, Dave
>> Would anyone have a sample FAT32 diska image file that would work with >> DOSFS >> for local desktop testing?
> Just format a USB thumb drive with the "/FS:FAT32" option from the > command line. No problem so long as it's over 32MB in size and less > than 2GB.
(I'm the OP) There must be a step missing here. I can format a USB flash drive but DOSFS requires an image file (HOSVER is defined in the makefile) that will be used to mimic the volume. I connected a 512M USB flash drive on drive G and formatted it for FAT32. Then I entered "dosfs g:\" at the command line and was given a "Cannot attach image file 'g:\'" error. It's looking for a true blue file just for testing purposes. Is it possible there's a way to extract the image file from the USB flash drive? JJS
John Speth wrote:
>>>Would anyone have a sample FAT32 diska image file that would work with >>>DOSFS >>>for local desktop testing?
Just in case you haven't tested with a FAT16 image, here is one with these parameters (output of 'partread' which is my version of 'partscan'): Partition 0 start sector 0x00000011 active 80 type 04 size 0000A307 Volume label ' ' 4 sector/s per cluster, 1 reserved sector/s, volume total 41735 sectors. 41 sectors per FAT, first FAT at sector #18, root dir at #100. (For FAT32, the root dir is a CLUSTER number, FAT12/16 it is a SECTOR number) 512 root dir entries, data area commences at sector #132. 10400 clusters (21299200 bytes) in data area, filesystem IDd as FAT16. root directory: file: 'TEST DIR' DIR 0 2 file: 'FOO TXT' 17 3 Input path to list: TEST.DIR Directory of TEST.DIR file: '. ' DIR 0 2 file: '.. ' DIR 0 0 file: 'BAR TXT' 24 4 Image file is at: http://ipx1.cybertheque.net/tmp/dosfs/testpart.img Michael
>>>>Would anyone have a sample FAT32 diska image file that would work with >>>>DOSFS >>>>for local desktop testing? > > Just in case you haven't tested with a FAT16 image, here is one with > these parameters (output of 'partread' which is my version of > 'partscan'): > > Partition 0 start sector 0x00000011 active 80 type 04 size 0000A307 > Volume label ' ' > 4 sector/s per cluster, 1 reserved sector/s, volume total 41735 sectors. > 41 sectors per FAT, first FAT at sector #18, root dir at #100. > (For FAT32, the root dir is a CLUSTER number, FAT12/16 it is a SECTOR > number) > 512 root dir entries, data area commences at sector #132. > 10400 clusters (21299200 bytes) in data area, filesystem IDd as FAT16. > > root directory: > > file: 'TEST DIR' DIR 0 2 > file: 'FOO TXT' 17 3 > > Input path to list: TEST.DIR > > Directory of TEST.DIR > file: '. ' DIR 0 2 > file: '.. ' DIR 0 0 > file: 'BAR TXT' 24 4 > > Image file is at: > http://ipx1.cybertheque.net/tmp/dosfs/testpart.img > > Michael
Thanks. That's exactly what I need. The http://ipx1.cybertheque.net server is down or busy now. I'll try again later. JJS
On Jun 17, 1:26=A0am, larwe <zwsdot...@gmail.com> wrote:
> On Jun 16, 7:25 pm, "John Speth" <johnsp...@yahoo.com> wrote: > > > Would anyone have a sample FAT32 diska image file that would work with D=
OSFS
> > for local desktop testing? > > I'd ask Lewin himself but he warns emphatically to not bother him with D=
OSFS
> > What I actually say is that you can ask all you want, but I don't > guarantee a response, and furthermore if I do respond and it involves > a bugfix, then the bugfix is not your private property, it is added to > the public source tree. > > Anyway - There is a 1GB FAT32 disk image at <http://www.larwe.com/temp/ > 1gb_fat32.zip>. It is about a 5.5MB download; unused sectors were > zeroed before imaging.
Thanks, Lewin. That's exactly what I needed. JJS
John Speth wrote:
>>>>>Would anyone have a sample FAT32 diska image file that would work with >>>>>DOSFS >>>>>for local desktop testing? >> >>Just in case you haven't tested with a FAT16 image, here is one with >>these parameters (output of 'partread' which is my version of >>'partscan'): >> >>Partition 0 start sector 0x00000011 active 80 type 04 size 0000A307 >>Volume label ' ' >>4 sector/s per cluster, 1 reserved sector/s, volume total 41735 sectors. >>41 sectors per FAT, first FAT at sector #18, root dir at #100. >>(For FAT32, the root dir is a CLUSTER number, FAT12/16 it is a SECTOR >>number) >>512 root dir entries, data area commences at sector #132. >>10400 clusters (21299200 bytes) in data area, filesystem IDd as FAT16. >> >>root directory: >> >>file: 'TEST DIR' DIR 0 2 >>file: 'FOO TXT' 17 3 >> >>Input path to list: TEST.DIR >> >>Directory of TEST.DIR >>file: '. ' DIR 0 2 >>file: '.. ' DIR 0 0 >>file: 'BAR TXT' 24 4 >> >>Image file is at: >> http://ipx1.cybertheque.net/tmp/dosfs/testpart.img >> >>Michael > > > Thanks. That's exactly what I need. The http://ipx1.cybertheque.net server > is down or busy now. I'll try again later.
Sorry, the URL was on the internal domain, it should be: http://www.cybertheque.org/tmp/dosfs/testpart.img Michael
John Speth wrote:
>>Just format a USB thumb drive with the "/FS:FAT32" option from the >>command line. No problem so long as it's over 32MB in size and less >>than 2GB. > > (I'm the OP) > > There must be a step missing here. I can format a USB flash drive but DOSFS > requires an image file (HOSVER is defined in the makefile) that will be used > to mimic the volume. > > I connected a 512M USB flash drive on drive G and formatted it for FAT32. > Then I entered "dosfs g:\" at the command line and was given a "Cannot > attach image file 'g:\'" error. It's looking for a true blue file just for > testing purposes.
Depending on how 'dosfs' accesses the file you specified, it may work to give it the file name "\\.\g:" (according to win32.hlp, this is the syntax to access a whole drive, but some Windows C libraries sabotage and do not support this syntax). This is how I test my file system implementation on live data. This is the equivalent of "/dev/hda1" etc. under Linux. You need admin rights, but if you can format your thumb drive, you probably already have them. Stefan