How can I add a string to the beginning of each file in a folder in bash?

Question

I want to be able to prepend a string to the beginning of each text file in a folder. How can I do this using bash on Linux?

Answer 1

You can do it like this without a loop and cat

sed -i '1i whatever' *

if you want to back up your files, use -i.bak

Or using awk

awk 'FNR==1{$0="whatever\n"$0;}{print $0>FILENAME}' *