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OPEN and read disk sector by sector

Posted: Mon May 18, 2020 4:36 pm
by tas3086
Using your TBscripting language, is it possible to read a hard disk and/or a partition sector by sector? Open seems to be file related. Read seems to do things to CR/LF pairs, Seek seems to ignore CR/LF in its positioning. Is there a way to seek to a specific sector, or LBA position?

TBOSDT does have an open that supports Drive and/or partition opening, and a COPY SECTOR command that will copy LBA data to a file. Do I need to (EXT) CALL these TBOSDT command operations to create a sector file, then back to tbscript commands to open read, analyze, and close that temporary sector file? It seems like a lot of hard drive and temporary file openings, closings overhead and would be required. But, it should work. It does not appear that there are any return codes to verify the success of the (EXT) TBOSDT Function calls. this may be a problem.

There must be a better and easier way?


Thanks in advance.

Re: OPEN and read disk sector by sector

Posted: Tue May 19, 2020 7:12 am
by Eric
The "copy sectors" without the /w switch is available from inside a script (with the ext function). Then you can read the file created in binary mode. This can be included inside a loop. Start reading the sectors from the starting lba of a partition.
For ex, to browse all the sectors from a partition:

sub main()
// disk number to read
hdnum=0
// partition number to read
pn=1
// number of a sectors to read in one time
nbsect=4096
// get info of the disk
h=GetHdInfo(hdnum)
if h and h.partition[pn] then
for i=0 to (h.partition[pn].size/nbsect)
// starting lba to read
lba=h.partition[pn].startlba+(nbsect*i)
// copy sectors to file "sector.dat"
ext("copy sectors " # hdnum # " " # lba # " " # nbsect # " sector.dat")
// open the file
f=open("sector.dat", "in", "binary")
if f>-1 then
s=readl(f, lof(f))
// get it in hexa (or in string with second parameter set to 0)
r=binary(s, 1)
// do what you want
...
close(f)
else
// unable to open file (unable to read sectors?)
ExitLoop
end if
next
else
// unable to read disk, or partition nonexistent
end if
end sub

Re: OPEN and read disk sector by sector

Posted: Wed May 20, 2020 12:20 am
by TeraByte Support
Also, on Linux you can access the device as a file.