How can I use awk to modify lines that match a certain pattern, but only if the NEXT line does not match another pattern?
For example take this fragment:
.... pattern1 100 200 300 pattern1 300 400 400 pattern2 300 900 700 pattern1 200 500 900 ...
I would like to modify all lines containing
pattern1, except for the second one which is followed by a line containing
This is similar to this question, but just the other way around.