Marius van Witzenburg We fight for our survival, we fight!

How to convert a string to lower case or UPPER case with Bash

Ever had a situation where you want the output or input in a BASH script to be lowercase or uppercase whatever happens but you couldn't find a way how to do that? You can!

Simply, use these two functions in your script:

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toLower() {
  echo $1 | tr "[:upper:]" "[:lower:]" 
} 
toUpper() {
  echo $1 | tr "[:lower:]" "[:upper:]" 
}
 
# Example
echo `toUpper hey`
echo `toLower HEY`

I hope this helps you out with writing your precious script