Question

I am trying to XOR two large binary values. However,

echo ${hashArray[1]}
echo ${hashArray[2]}
echo $((${hashArray[1]} ^ ${hashArray[2]}))

gives:

10100100000111101011100001101110000110000100001000000111001001100010110000010010111101100110111001111100010010000000010101110111

00001110110000010110101101011011100101101000011100011101001101101010000100110001001110101101111100010001111010100011010000000100

4018181242766406943

Why does echo $((${hashArray[1]} ^ ${hashArray[2]})) output a decimal number? Shouldn’t it be another large binary value?

Answer 1

Do it “bitwise” like that:

#!/bin/bash

a="101"
b="011"

out=""
for ((i=0; i < ${#a}; i++ )); do
   out=${out}$((${a:$i:1} ^ ${b:$i:1}))
done

echo ${a} ^ ${b} = $out

output:

101 ^ 011 = 110

edit: The inputs need to have the same length!