Is there a utility like hexdump that will handle non-native endian-ness?

Is there a utility like hexdump that will handle non-native endian-ness?

Yes, the utility is called Perl.

Well actually Data::HexDumper - though you could roll your own.

number_format
A string specifying how to format the data. It can be any of the following,
which you will notice have the same meanings as they do to perl's pack function:

C        - unsigned char
S        - unsigned 16-bit, native endianness
v or S<  - unsigned 16-bit, little-endian
n or S>  - unsigned 16-bit, big-endian
L        - unsigned 32-bit, native endianness
V or L<  - unsigned 32-bit, little-endian
N or L>  - unsigned 32-bit, big-endian
Q        - unsigned 64-bit, native endianness
Q<       - unsigned 64-bit, little-endian
Q>       - unsigned 64-bit, big-endian

At least for 16-bit words one can pipe it through dd conv=swab as in,

cat file.dat | dd conv=swab | od -t x2

As pixelbeat suggests, you could use objcopy:

$ objcopy -I binary -O binary --reverse-bytes=num inputfile.bin outputfile.bin

where num is 2 for 16 bit words, 4 for 32 bit words and 8 for 64 bit words.

Unfortunately objcopy has no option to accept input from stdin or write output to stdout, so in order to use it as a pipe you would need to write a wrapper script that creates temporary files.

This answer is copied from https://stackoverflow.com/a/19288235/1979048 and from https://serverfault.com/a/329207/157443.