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combining files and no dupes

0 votes

Having looked at "man join" wasn't sure of it's use here.

Unknown number of files, constant is extension .list
(For testing purposes only using two)

cat *.list >> output.joined | sort -u

How can I test if the output.joined,
is indeed the combined two lists with dupes removed.

posted May 14, 2013 by anonymous

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2 Answers

0 votes


cat *.list >> output.joined | sort -u | uniq --all-repeated
a try. If the output is empty ===> no dupes!

answer May 14, 2013 by anonymous
0 votes

1) You probably want '>' rather than '>>' if you're only running this once. Not that it makes a difference here but it's superfluous.

2) Since you're sending the output of 'cat' to a file, the pipe won't get any input, so you're you sorting nothing. If you actually want to capture the output in a file, you can use 'tee':

sort *.list | tee output | sort -u

or just run the two commands separately:

cat *.list > output
sort -u < output

If not, then "cat *.list|sort -u" is enough.

answer May 14, 2013 by anonymous
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