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To have only unique lines in a file

Terminal - To have only unique lines in a file
sort file1.txt | uniq > file2.txt
2009-03-14 20:24:06
User: rain
Functions: sort uniq
3
To have only unique lines in a file

Alternatives

There are 4 alternatives - vote for the best!

Terminal - Alternatives

Know a better way?

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What others think

A simpler one would be to use sort's -u flag:

sort -u file1.txt > file2.txt
Comment by dfego 300 weeks and 5 days ago

uniq f1.txt > f2.txt

Comment by mpb 300 weeks and 5 days ago

@mpb: That won't work; uniq's manpage says:

Note: 'uniq' does not detect repeated lines unless they are adjacent. You may want to sort the input first, or use `sort -u' without `uniq'.

Comment by dfego 300 weeks and 5 days ago

If you want to preserve the original order:

awk '!_[$0]++' infile

Use nawk or /usr/xpg4/bin/awk on Solaris.

Comment by radoulov 300 weeks and 5 days ago

@radoulov: nifty!

Comment by mpb 300 weeks and 4 days ago

sort -u is better.

Comment by ozymandias 300 weeks and 3 days ago

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