Thanks for your reply, but I want it to loop through the string and then perform an action for each occurrance of r, not just once. eg. "rover" would return 11 in this example because there're two r's in it.

I've tried adapting your code so it looks something like this:

echo $string | awk '{
for (i=1;i<=length($0);i++)
do
if [[ (substr($0,i,1) == *r*) ]] ; then
echo "1"
fi ;
done
}'


but get parse errors all over the place:

awk: cmd. line:4: if [[ (substr($0,i,1) == *r*) ]] ; then
awk: cmd. line:4: ^ parse error
awk: cmd. line:4: if [[ (substr($0,i,1) == *r*) ]] ; then
awk: cmd. line:4: ^ parse error
awk: cmd. line:4: if [[ (substr($0,i,1) == *r*) ]] ; then
awk: cmd. line:4: ^ parse error

Any more ideas?