This assignment must be uploaded to the Moodle submission page for Homework 8.
The setup
On the computer montreat.cs.unca.edu there are three images of FAT file systems in the following regular files.
- /csciloc/sysadmin/images/CSCI331BIG.img
- /csciloc/sysadmin/images/CSCI331MID.img
- /csciloc/sysadmin/images/CSCI331TNY.img
Your job is to use dd to make a copy of the first 512-byte sector, the BPB (BIOS Parameter Brock), of each of these images into your own directory. Then you are to use od or hexdump to print the following fields from the BPB in a readable fashion.
BS_OEMName
BPB_BytsPerSec
BPB_SecPerClus
BPB_RsvdSecCnt
BPB_NumFATs
BS_FilSysType
Except for the BS_FilSysType
field, all of these positions
are located in the same offset for both FAT16 and FAT32 file systems.
However, they may differ in value.
What to turn in?
I am afraid that script is just unreadable. I’d prefer that you run emacs inside a shell buffer.
If that doesn’t work for you, see if you can get Perl script by dewtall to work. Everyone needs to see Perl at least once.
It is fine to work in groups, but you must type in your own
dd
and od
commands.
Be careful, these are old-style Unix commands.
They have a very odd syntax.
Suggested reference materials
You will need to review
Microsoft’s specification of the FAT file system.
The PHOBOS tutorial
of the FAT file system is also useful.
It’s not hard to use
dd
to copy the first 512 bytes of
a file.
hexdump
isn’t that bad,
but the true hackers use
od
.