Hex2dec

<highlightSyntax>

1. !/bin/bash
2. hex to decimal number converter
3. mutante (s23.org) 11/2006

read -p "Give me a hex number " hex length=${#hex} i=0 result=0 let length-- pos=0 while [ $length -ge 0 ]; do digit=${hex:$length:1}

case "$digit" in A | a) ddigit=10;; B | b) ddigit=11;; C | c) ddigit=12;; D | d) ddigit=13;; E | e) ddigit=14;; F | f) ddigit=15;; [0-9]) ddigit=$digit;;

• ) echo "Bad input. Only 0-9 and a-f are allowed."; exit 1;;

esac factor=`echo "(16^$pos)" | bc` subresult=`echo "$factor*$ddigit" | bc` echo "[$pos]: $digit = $ddigit * (16^$pos) = $ddigit * $factor = $subresult" let result=$result+$subresult let pos++ let length-- done

echo "Result: $hex (hex) is $result (dec)" | boxes exit 0 </highlightSyntax>

 ./hex2dec.sh

Give me a hex number 523F
[0]: F = 15 * (16^0) = 15 * 1 = 15
[1]: 3 = 3 * (16^1) = 3 * 16 = 48
[2]: 2 = 2 * (16^2) = 2 * 256 = 512
[3]: 5 = 5 * (16^3) = 5 * 4096 = 20480
/*************************************/
/* Result: 523F (hex) is 21055 (dec) */
/*************************************/