Converting lowercase to uppercase in shell script

shell

Solution

Below Works, Try this.

bash-3.2$echo lower to upper | tr '[:lower:]' '[:upper:]'
LOWER TO UPPER  

# To Save in the variable use below
var=$(echo lower to upper | tr '[:lower:]' '[:upper:]')

Problem

I tried to convert a lowercase string to uppercase and assign it to a variable using the following code The script is written in .tn extension ``` set y a12 y_up=$( tr '[A-Z]' '[a-z]' <<< $y) echo $y echo $y_up ``` But I am getting the error ``` invalid command name "A-Z" while executing "A-Z" invoked from within "y_up=$( tr '[A-Z]' '[a-z]' <<< $y) " ``` How can I convert this?

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