Shell Programming and Scripting

Hi there

i have a script which will create unix user accounts. Id like to validate the entered string so that it is specifically 8 characters or less and consists of only [a-z] ! not [A-Z][0-9][' ']

Is there a way to validate a string against a regular expression.. i.e

Code:

size=`printf "$var | wc -m`

if [ $var = [a-z] && $size -lt 9 ] ; then

success
else
failure
fi

I realise its kind of gibberish above but i just wanted to get the idea across


somebody i know suggested i do this

Code:

case $var in
+([a-z])) echo "success" ;;
*)          echo "failure"   ;;
esac

but this doesn't work ...does anybody have any pointers for me ?

Cheers

It depends on the shell being used.

Depending on what you have available. You could do this with 'expr', shell builtin, or another external utility such as tr.