Auto increment a character in shell

[Chua Wen Ching]

I had some problems on running the script below:

inc.sh
-------
str1="ABCDEFGHIJKLMNOPQRSTUVWXYZ"
str2="BCDEFGHIJKLMNOPQRSTUVWXYZA"
pos=`expr index $str1 $char`
char=`expr substr $str2 $pos 1`
echo $char

i want to use the script to autogenerate a character in bourne shell. I am using hp-ux 10.20. Actually i found out a shorter way, but i want to know what is the solution for the inc.sh above. Thank you.

[harry d brown jr · Accepted solution]

echo `expr $RANDOM % 26` `expr $RANDOM % 26` | awk '{ alphabet = "abcdefghijklmnopqrstuvwxyz"; printf("%s%s\n", substr(alphabet,$1,1), substr(alphabet,$2,1));}'


live free or die
harry

[Chua Wen Ching]

Thanks a lot. The codes really help in to solve a lot of problems.

[H.Merijn Brand (procura]

PC03:/W 508 $ perl -le '$a="a";print++$a'
b
PC03:/W 509 $