Extract sequences of bytes from binary for differents blocks
Hello to all,
I would like to search sequences of bytes inside big binary file.
The bin file contains blocks of information, each block begins is estructured as follow:
1- Each block begins with the hex 32 (1 byte) and ends with FF. After the FF of the last block, it follows 33.
2- Next sequence to extract is the correlative (3 bytes) --> I mean, 1, 2, 3...N
3- Next sequence to extract is Product Series (8 bytes) --> The first 4 bytes are always "99 11 45 27"
4- Next sequence to extract is Product Model (8 bytes) --> The first 2 bytes are always "73 49"
There some other sequences of bytes I need to extract for each block, but I need somebody could help me first
saying me how to begin to do this for the 4 items mentioned above.
It is possible to do it in shell script, combining awk etc or what do you suggest me?
PD: It would be better not to save an hexdump in a textfile first, because the binary could be of 2GB. Would be better a way
to extract the sequences directly from the binary.
If you intend to attempt to put the binary values into a _string_variable_ then 0, (zero), is not possible directly under bash, all other values are possible. You will have to detect the 0's and slot in "\0" instead.
So from the 256 bytes of DEMO data in the pointer above only 255, (1 to 255), can be placed into a _variable_. It is easy to add 2 more bytes to represent a 0 as mentioned above but makes the DEMO string 257 bytes in size...
However transferring to another binary file is easy as shown in the DEMO...
If there is an option extract the sequences directly from the binary file would be better and faster I think,
I'm not sure if it is possible with bash or Perl or another option you can suggest me.
Hello Jotne,
Thanks for your help. Your script detects the position of the sequences but I would like to
extract those sequences to a new file having in the output file one line per information of each block
in binary.
Hello wisecracker,
I'll check the option you mention, but it is possible with your script to extract the complete byte sequence?
I sat down yesterday to write this script and have just realised that my methodology is broken........
In essense I have.....
----------------------------------------------------------------- (This line really is in the file)
Service ID: 12345 ... (7 Replies)
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>P02649
MKVLWAALLVTFLAGCQAKVEQAVETEPEPELRQQTEWQSGQRWELALGRFWDYLRWVQT
LSEQVQEELLSSQVTQELRALMDETMKELKAYKSELEEQLTPVAEETRARLSKELQAAQA
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I have a file with more than 28000 records and it looks like below..
>mm10_refflat_ABCD range=chr1:1234567-2345678
tgtgcacactacacatgactagtacatgactagac....so on
>mm10_refflat_BCD range=chr1:3234567-4545678...
tgtgcacactacacatgactagtatgtgcacactacacatgactagta
.
.
.
.
.
so on
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ASDFGHJKLQWERTYUIOPZXCVBNM
first block: ASDFGHJKL
1nd block: SDFGHJKLQ
What I have so far only gives me the first block, can anyone please explain why?
cat... (7 Replies)
Hello,
I have come across the necessity for me to deal with binary sequences and I had a few questions.
1- Does any UNIX scripting language provide any tool or command for converting text data to binary sequences? Example of binary sequence: "0x97 0x93 0x85 0x40 0xd5 0xd6 0xd7"
2- If I want... (2 Replies)
Hi all,
Does anybody know or guide me on how to remove the first N bytes and the last N bytes from a binary file? Is there any AWK or SED or any command that I can use to achieve this?
Your help is greatly appreciated!!
Best Regards,
Naveen. (1 Reply)
