When restoring a file in my uninstall program I need to remove the lines I added to a file during the install. In between the file can be modified by the users.

Assume file1 is as follow:

xxx str2 xxxx
.....
...The Following lines containing str* have to be removed...
xxx str1 xxxx
xxx str2 xxxxx
xxxx aaa, xxx
xxxxx str4 xxx


Result:
xxx str2 xxxx
.....
xxxx aaa, xxx

I know how to remove the line "The Following lines containing str* ...":
ln=`grep -n 'The Following lines containing' | cut -d',' -f 1`
sed $lnd file1

I also know how to remove the lines with str* in it with awk:
awk 'BEGIN { FS=";" } { if ( $2 ~ /str*/ ) { print $0 } }' file1 > outputF

However, how to do this without removing the lines with str* before the line "The Following lines containing str* have to be removed" ? (the first line in file1 for example).

Any help would be greatly appreciated!!

Note sure if this works for gnu sed only...

hi,
Hope this one can help you.

A cunning approach would be to generate a patch file at install time that would then remove the lines you added, that could be done by savinging a backup of the original and doing a diff at installation time, then deleting the backup. Then at uninstall time you apply the patch.

Ygor:
That doesn't work on my sunOS 5.10. But thanks the same.

summer_cherry:
It works perfect! -and I've learned a lot about this nawk utility today. Thanks for your help!

porter:
That was what I did- however, I wanted the installation program to be able to run as many times as the users like without the need of uninstallation in between- and every time it runs it should be as clean as the first time... I thought that'd make it all a bit more dynamic...
Thanks for the suggestion!!

Hey,

To delete a line where a pattern matches, you can use sed.

sed '/^[Mm]ango/d' file1.txt

Above command will delete all the lines which starts with the word Mango or mango.

Similarly you can search the pattern in a line, if that will be found then delete the line.

Try the following :

Jean-Pierre.