To have only unique lines in a file

sort file1.txt | uniq > file2.txt

3
By: rain
2009-03-14 20:24:06

What Others Think

A simpler one would be to use sort's -u flag: sort -u file1.txt > file2.txt
dfego · 504 weeks and 5 days ago
uniq f1.txt > f2.txt
mpb · 504 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'.
dfego · 504 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.
radoulov · 504 weeks and 4 days ago
@radoulov: nifty!
mpb · 504 weeks and 4 days ago
sort -u is better.
ozymandias · 504 weeks and 3 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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