gistfile1.sh-session

francois@francois:/home/francois  $ mkdir a b
francois@francois:/home/francois  $ echo "A" > a/A
francois@francois:/home/francois  $ echo "B" > b/B
francois@francois:/home/francois  $ echo "C" > a/C
francois@francois:/home/francois  $ envdir a envdir b bash
francois@francois:~$ echo $A
A
francois@francois:~$ echo $B
B
francois@francois:~$ echo $C
C
francois@francois:~$ exit
francois@francois:/home/francois  $ echo "D" > b/B
francois@francois:/home/francois  $ envdir a envdir b bash
francois@francois:~$ echo $A
A
francois@francois:~$ echo $B
D
francois@francois:~$ echo $C
C
francois@francois:~$ exit