Sed or Grep to replace until end of line after pattern match


I need to replace all the characters after a pattern match until the end of the line while keeping the matched pattern


should read


Everything I've tried so far has deleted the PATTERN1 as well…

Best Solution

Using sed

sed -r 's/(PATTERN1).*/\1STUFFI_WANT_TO_INSERT/' file

You need to capture PATTERN1 and use \1 in replacement string