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Compare and Remove duplicate lines from txt

 
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# 8  
Old 08-16-2008
then just try
grep -v -f file2 file1 >> newfile
mv newfile file1
# 9  
Old 08-16-2008
That worked great vidyadhar. Thanks!
# 10  
Old 08-16-2008
I gave you a line-by-line solution 'cause I figured you could want to do some processing for each line.
# 11  
Old 08-17-2008
Quote:
Originally Posted by rmarcano
Hello,
I am a total linux newbie and I can't seem to find a solution to this little problem.
I have two text files with a huge list of URLS. Let's call them file1.txt and file2.txt

What I want to do is grab an URL from file2.txt, search file1.txt for the URL and if found, delete it from file1.txt.

What would be the best way to go around doing this? Would I need a full bash script or does anyone know a simple oneliner to do it.

Thanks,
Rafael

Dirty but here is a superfast way to do it.

1) Load all the urls from file1.txt to a hashmap
2) Parse file2.txt each line one by one
3) if entry in file2.txt found in file1.txt delete the hashmap entry ( constructed for file1.txt )
4) loop through file2.txt till EOF
5) Write all the contents of remaining hash map entry to another file - this should give the output that you intend for
# 12  
Old 08-18-2008
Just a question: what is wrong with merging the files first and use "sort -u" then? I suppose you want to add the content of one file to the other but don't want to create duplicates, right? If so:

Code:
sort -u file1 file2 > tempfile

I hope this helps.

bakunin
 
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