Where is my exclusive OR

[clickit]

I am running bash 3.1 under Linux 2.6
When I try j=`expr $jp ^ $mori` it fails to recognize the "^". Replacing with a "+" works. A google search shows that that operator is available but the text man page does not show it.
Can 1) someone explain this? 2) is there a work around so I can do an exclusive OR?
Thanks all.

[vsemaska]

The expr (evaluate expression) utility doesn't recognize '^' as a valid oprator. The '+' simply means add the 2 no.s together, it isn't performing a XOR.

XOR is built into bash itself. Here's an example:

# cat a.bash
#!/bin/bash

let "c=1^1"
echo $c

let "c=1^0"
echo $c
#./a.bash
0
1

[clickit]

Thanks really big!! I tried both with and without quotes and the following returned:
mask=15
let mask=$mask^1
echo $mask ------------>14
let "mask=$mask^2"
echo $mask ------------>12
Super