Shell Programming and Scripting

Hi,

I'm having some trouble with using "case...esac" in Bash.

I've googled it and am stuggling to understand the syntax and how to do certain things.

Firstly, I want to be able to choose a case based on a variable number

For example, I have in my code a place where a user can enter a number using read.

Code:

read SEL

Then I want to use a case to decide what should be done.

I want it to be able to figure out whether it is a number or letter.

Using "if" you can always use

Code:

if [ $SEL -eq $SEL 2>/dev/null ]
then
    echo "Is Number"
else
    echo "Contains Letters or Symbols"
fi

I also want to have a case based on ranges of numbers too, but the upper range isn't a fixed number

So, in my code I find what the last number will be and define it as LASTNUM

In my case I want it be

Code:

case "$SEL"
    0)
        # Do Something for 0
    ;;
    1-$LASTNUM)
        # Do something for between 1 and LASTNUM
    ;;
    Any variation of Q q or Quit)
       # Do something for Q, q or Quit
    ;;
    *)
       # Do something for everything else
    ;;
esac

I've been really struggling and any help would be much appreciated.

Thanks in advance!

Code:

case "$SEL" in
    0)
       echo zero
    ;;
    [1-9]*)
       echo number
    ;;
    [qQ]|[qQ]uit)
       echo quit
    ;;
    *)
       echo no choice
    ;;
esac

Thanks that works perfectly!