Add couple new lines before the second pattern in file from shell script
 

Hi Friends,
I want to add couple lines before *pattern2 after *pattern1 in a text file from shell script. *pattern2 is being used for many times in the file. Appreciate for your kind help. See detail below:

<Original file>
*pattern0
x
*pattern2

*pattern1
original lines
*pattern2

<New file after modification>
*pattern0
x
*pattern2

*pattern1
original lines
new line1
new line2
*pattern2

Thank you for your help,
Jim

1) Please use [code][/code] tags around your code, to preserve formatting and to improve readability.

2) It's generally better to provide real-life examples of the text to be modified than simplified mock-up versions. Are there any reserved characters in the text we may have to account for, for example? Also, how big is the file? What is its source? It's faster and easier to devise useful solutions when we know exactly what we're dealing with.

3) For the same reason you should also tell us about all the possible variations in the text patterns to match. Can pattern1 also appear more than once, for example? Or appear alone without pattern2 appearing? Can the pattern1..pattern2 block appear more than once? What do you want to happen in any of these cases?

The main tools used for text manipulation are sed and awk.
Assuming the above simple case is representative, then sed can do it:
When the command matches a line containing pattern1, it continues to match until it finds a line with pattern2. Then it matches within that block for pattern2 (the last line) and inserts the required text in front of it. Note that sed requires a literal line break after the inserted text in this case, in order to know where the inserted text ends and the command continues.

Here are a few useful sed and awk references.
http://www.grymoire.com/Unix/Sed.html
http://sed.sourceforge.net/sedfaq.html
http://sed.sourceforge.net/sed1line.txt

http://www.grymoire.com/Unix/Awk.html
http://www.gnu.org/software/gawk/man...ode/index.html
http://www.informatik.uni-hamburg.de.../gawk_toc.html
http://www.pement.org/awk/awk1line.txt
http://www.catonmat.net/blog/awk-one...ined-part-one/

Thanks for help. I got an error.
# sed '/pattern1/,/pattern2/ {/pattern2/i NEWLINE1\nNEWLINE2}' testfile

sed: -e expression #1, char 0: unmatched `{'

1) I told you to use code tags.

2) I told you that you need to use a literal newline after the inserted text.

Sorry, I don't understand what you say. I have not integrated it into script yet. I got that error when I ran it from command line. I think it should be able to run from command line, am I right? Can you please provide a complete sed command for this solution? pattern1 only shows up once in my file. Thank you.

The sed command must be broken up onto two separate lines, exactly as I posted it.

If there's anything after the text to be inserted, it must be put on a new line.

How can I test this from Linux command line?

Works, thanks!!!!!!