How to ignore lines that are between two patterns

Question

I've used sed to print all lines starting from one pattern ending in another:

Lets say file1 contents are these:

outside-text1
==START
inner-text1
==END
outside-text2
==START
inner-text2
==END

The command:

sed -n '/==START/,/==END/p' file1

will print :

==START
inner-text1
==END
==START
inner-text2
==END

In my case I would like to print:

outside-text1
outside-text2

Possible duplicate of [Remove lines which are between given patterns from a file (using Unix tools)](https://stackoverflow.com/questions/1996585/remove-lines-which-are-between-given-patterns-from-a-file-using-unix-tools) — Sundeep, Jan 25 '18 at 16:02

score 2 · Accepted Answer · answered Jan 25 '18 at 15:57

2

Negate the match with !.

$ sed -n '/==START/,/==END/!p' file1
outside-text1
outside-text2

answered Jan 25 '18 at 15:57

iamauser

score 2 · Answer 2 · answered Jan 25 '18 at 16:17

2

Or even easier, just use the d (delete) function to delete from the start to end patterns:

$ sed '/==START/,/==END/d' file.txt
outside-text1
outside-text2

It's just a cleaner alternative to suppressing printing of pattern-space and negating the print.

answered Jan 25 '18 at 16:17

David C. Rankin

Gotcha -- you had me wondering what the heck was going on... `:)` – David C. Rankin Jan 25 '18 at 16:24
@DavidC.Rankin, no offense sir but it was added in my 2nd solution too :) – RavinderSingh13 Jan 25 '18 at 16:52

RavinderSingh13 · Answer 3 · 2018-01-25T16:11:48.003

1

Following awk may help you in same.

awk '/^==END/{flag="";next} /^==START/{flag=1;next} !flag'   Input_file

OR

awk '/^==START/{flag=1;} /^==END/{flag="";next} !flag'  Input_file

OR

awk '/^==START/{flag=1} !flag;  /^==END/{flag=""}'  Input_file

Output will be as follows.

outside-text1
outside-text2

Solution 2nd: Following sed may also help you in same.

sed  '/==START/,/==END/d'  Input_file

edited Jan 25 '18 at 16:11

answered Jan 25 '18 at 16:02

RavinderSingh13

1

that can still be simplified ;) – Sundeep Jan 25 '18 at 16:10
@Sundeep, thanks, please see edited answer now and let me know if anything needed please. – RavinderSingh13 Jan 25 '18 at 16:12
1

[This answer](https://stackoverflow.com/a/15955111/3266847) has a nice way of doing it in awk. – Benjamin W. Jan 25 '18 at 16:44

3 Answers3