Saturday, June 4, 2022

[SOLVED] sed one-liner to convert all uppercase to lowercase?

Issue

I have a textfile in which some words are printed in ALL CAPS. I want to be able to just convert everything in the textfile to lowercase, using sed. That means that the first sentence would then read, 'i have a textfile in which some words are printed in all caps.'


Solution

With tr:

# Converts upper to lower case 
$ tr '[:upper:]' '[:lower:]' < input.txt > output.txt

# Converts lower to upper case
$ tr '[:lower:]' '[:upper:]' < input.txt > output.txt

Or, sed on GNU (but not BSD or Mac as they don't support \L or \U):

# Converts upper to lower case
$ sed -e 's/\(.*\)/\L\1/' input.txt > output.txt

# Converts lower to upper case
$ sed -e 's/\(.*\)/\U\1/' input.txt > output.txt
 


Answered By - magnetar
Answer Checked By - Pedro (WPSolving Volunteer)