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

This will do that. You could make it more efficient if you are doing the same text to each file...

for f in *; do 
  echo "whatever" > tmpfile
  cat $f >> tmpfile
  mv tmpfile $f
done