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}'

Answer 1

Using xxd is better for this job:

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.

Answer 2

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.)