How to remove multiple lines per occurrence in a file? Say I have this 857835 line file, containing stuff like this: a1 rubbish1 rubbish2 rubbish3 rubbish4 a1 rubbish5 rubbish6 rubbish7 rubbish8 And I wish to remove all occurences of `a1` and the next line (`rubbish1` and `rubbish5` in this example). How do I do it? I've tried `grep 'a1' -v -A1` to no avail, and my sed skillz are not really great :} My Google-fu has not been able to help me this time, someone please help!

Try:


sed -e '/^a1$/,+1d' "filename"


This means from /^a1$/ to the next line, delete

The ^ and $ ensure you match the whole line, so a hidden a1 will not be matched.