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linuxbashshellhexxor

echo unsigned 64 bit variable

I have the following shell code:

Val1=0123456789abcdef
Val2=fedcba9876543210

Val3_dec=$((16#$Val1 ^ 16#$Val2))
Val3=`echo "obase=16; $Val3_dec" | bc`
echo $Val1
echo $Val2
echo $Val3_dec 
echo $Val3

with the corresponding output:

0123456789abcdef
fedcba9876543210
-1
-1

unfortunately the output of Val3 is signed negative, but I need it to be a 64 bit unsigned output in HEX. Like:

0123456789abcdef
fedcba9876543210
-1    (the output of Val3_dec does not matter)
ffffffffffffffff

Some ideas?

Solution

  • Use printf:

    #!/bin/bash
Val1=0123456789abcdef
Val2=fedcba9876543210

Val3_dec=$((16#$Val1 ^ 16#$Val2))
Val3=`echo "obase=16; $Val3_dec" | bc`
echo $Val1
echo $Val2
printf "%d\n" $Val3_dec 
printf "%x\n" $Val3

    Results:

    $ ./test.sh 
0123456789abcdef
fedcba9876543210
-1
ffffffffffffffff