How to print only the hex values from hexdump without the line numbers or the ASCII table? [duplicate]

Question

following Convert decimal to hexadecimal in UNIX shell script

I am trying to print only the hex values from hexdump, i.e. don't print the lines numbers and the ASCII table.

But the following command line doesn't print anything:

hexdump -n 50 -Cs 10 file.bin |  awk '{for(i=NF-17; i>2; --i) print $i}'

Begird

age is not the primary factor, but rather upvotes and answer quality ;-) meta.#252438 – Woolley

hexdump file.bin | sed "s/[^ ]* //1" This will remove the line numbers, by default the ascii table wouldn't be printed. – Marijn

Answer 1

You can specify the exact format that you want hexdump to use for output, but it's a bit tricky. Here's the default output, minus the file offsets:

hexdump -e '16/1 "%02x " "\n"' file.bin

(To me, it looks like this would produce an extra trailing space at the end of each line, but for some reason it doesn't.)

Ambassadress

Great!! Usefull for me this answer! But I think is better also to have -C option. And if you add cut -c 9- | head -n 1 your output will display only the hex numbers. – Britanybritches

This blog entry shows more examples how to modify the output format of hexdump. – Eckman

Add -v to list every line and not to compress same lines with * – Ronda

Answer 2

Using xxd might be a better option for this task:

xxd -p -l 50 -seek 10 file.bin

From man xxd:

xxd - make a hexdump or do the reverse.

    -p | -ps | -postscript | -plain
        output in postscript continuous hexdump style. Also known as plain hexdump style.

    -l len | -len len
        stop after writing <len> octets.
 
    -seek offset
        When used after -r: revert with <offset> added to file positions found in hexdump.

Begird

@andsens hexdump is in busybox, and thus available on embedded, whilst xxd isn't :Ь – Echinus

Answer 3

As an alternative, consider using xxd -p file.bin.

Plossl

Answer 4

First of all, remove -C which is emitting the ascii information.

Then you could drop the offset with

hexdump -n 50 -s 10 file.bin | cut -c 9-

Longley

it seems to work but changes the endian... – Begird