Linux Pocket Guide, 2nd Edition

Name

xxd — stdin  stdout  - file  -- opt  --help  --version

Synopsis

xxd [options] [files]

Similar to od, xxd produces a hexadecimal or binary dump of a file in several different formats. It can also do the reverse, converting from its hex dump format back into the original data. For example, here’s a hex dump of binary file /usr/bin/who:

$ xxd /usr/bin/who
0000000: 7f45 4c46 0101 0100 0000 ... 0000 .ELF............
0000010: 0200 0300 0100 0000 a08c ... 0000 ............4...
0000020: 6824 0000 0000 0000 3400 ... 2800 h$......4. ...(.
0000030: 1900 1800 0600 0000 3400 ... 0408 ........4...4...
...

The left column indicates the file offset of the row, the next eight columns contain the data, and the final column displays the printable characters in the row, if any.

By default, xxd outputs three columns: file offsets, the data in hex, and the data as text (printable characters only).

Useful options

-l N	Display only the first N bytes. (Default displays the entire file,)
-s N	Skip the first N bytes of the file.
-s -N	Begin N bytes from the end of the file. (There is also a +N syntax for more advanced skipping through standard input; see the manpage.)
-c N	Display N bytes per row. (Default=16)
-g N	Group each row of bytes into sequences of N bytes, separated by whitespace, like od -s. (Default=2)
-b	Display the output in binary instead of hexadecimal.
-u	Display the output in uppercase hexadecimal instead of lowercase.
-p	Display the output as a plain hexdump, 60 contiguous ...