$ curl cheat.sh/
 cheat.sheets:hexdump 
# side-by-side hexadecimal and ASCII view of the first 128 bytes of a file
hexdump -C -n128 /etc/passwd

# Convert a binary file to C Array
hexdump -v -e '16/1 "0x%02X, "' -e '"\n"' file.bin > hexarray.h

# Convert a binary file to Shell code
hexdump -v -e '"\\""x" 1/1 "%02x" ""'

# Generate random MAC address
hexdump -n6 -e '/1 ":%02X"' /dev/random|sed s/^://g

 tldr:hexdump 
# hexdump
# An ASCII, decimal, hexadecimal, octal dump.
# More information: <https://manned.org/hexdump>.

# Print the hexadecimal representation of a file, replacing duplicate lines by '*':
hexdump path/to/file

# Display the input offset in hexadecimal and its ASCII representation in two columns:
hexdump -C path/to/file

# Display the hexadecimal representation of a file, but interpret only n bytes of the input:
hexdump -C -nnumber_of_bytes path/to/file

# Don't replace duplicate lines with '*':
hexdump --no-squeezing path/to/file

$
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