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Trying to write a script that will delete items that are NOT in a file. For example:
Quote:
list.txt:
twantrd
joe
mary
list1.txt:
twantrd
joe
mary
sue
john
So, list.txt is a list of items I want to keep. List1.txt contains all the items in a directory. Pretty much, I want to remove "sue" and "john". Not quite sure which direction I should take on how to write this bash script. If you guys can guide me a way, that would be great. Thanks!
Can you please post how it was done so others with the same question can read the answer in future.
Sure. The command 'comm' was the answer. It compares 2 sorted files line by line and describes what matches and what doesn't match in columns. Very simple to use.
The grep -v option didn't work. Well, I was checking each item in the list with a for loop and doing a grep -v against the other list and that gave me incorrect results.
If I did a 'grep -v twantrd list1.txt' it would show up "joe, mary, sue, john". However, that's incorrect as I just want to remove "sue" and "john". However, if you could provide the right way in doing a grep -v that works for my situation, that would be awesome. Thanks.
-twantrd
The grep -v option didn't work. Well, I was checking each item in the list with a for loop and doing a grep -v against the other list and that gave me incorrect results.
If I did a 'grep -v twantrd list1.txt' it would show up "joe, mary, sue, john". However, that's incorrect as I just want to remove "sue" and "john". However, if you could provide the right way in doing a grep -v that works for my situation, that would be awesome. Thanks.
-twantrd
i didn't understand the original post but this seems to be what you want:
Code:
schneidz@lq:/twantrd> cat list1.txt
twantrd
joe
mary
schneidz@lq:/twantrd> cat list2.txt
twantrd
joe
mary
sue
john
schneidz@lq:/twantrd> grep -f list1.txt list2.txt
twantrd
joe
mary
schneidz@lq:/twantrd>
sounds like you are deleting something that doesn't exist.
Correct, something that doesn't exist in 1 file but does in another. Therefore, I just want to remove the items that are unique. Anyhow, I got my answer. Thanks for the help!
Correct, something that doesn't exist in 1 file but does in another. Therefore, I just want to remove the items that are unique. Anyhow, I got my answer. Thanks for the help!
-twantrd
glad you got the answer by yourself. sometimes just asking for suggestions helps get the gears turning.
for anyone else wanting another suggestion:
try cat-ing both lists into 1 file then uniq -u the results.
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