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linux - Read a single sector from a disk

I am trying to read a single specific sector from the disk directly. I've currently run out of ideas and any suggestions how to go about it would be great!

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Try something like this to do it from the CLI:

# df -h .
Filesystem            Size  Used Avail Use% Mounted on
/dev/sda2              27G   24G  1.6G  94% /
# dd bs=512 if=/dev/sda2 of=/tmp/sector200 skip=200 count=1
1+0 records in
1+0 records out

From man 4 sd:

FILES
   /dev/sd[a-h]: the whole device
   /dev/sd[a-h][0-8]: individual block partitions

And if you want to do this from within a program, just use a combination of system calls from man 2 ... like open, lseek,, and read, with the parameters from the dd example.


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