>Usage
uniq is a command used to filter out repeated lines in a text file. It’s perfect for cleaning up duplicate entries, leaving only the unique occurrences of each line in the file or stream.
>Synopsis
>Options
-c
-c (count occurrences): Shows how many times each line appears.
Example 1:
-zsh
> echo -e "apple\napple\nbanana" | uniq -c
2 apple
1 banana
-d
-d (only repeated lines): Shows only the lines that appear more than once.
Example 2:
-zsh
> echo -e "apple\nbanana\napple" | uniq -d
apple
-u
-u (only unique lines): Shows only the lines that appear once.
Example 3:
-zsh
> echo -e "apple\nbanana\napple" | uniq -u
banana
-i
-i (ignore case): Ignores case when comparing lines.
Example 4:
-zsh
> echo -e "apple\nApple\nbanana" | uniq -i
apple
banana
-f
-f (skip fields): Skips the first N fields when comparing lines.
Example 5:
-zsh
> echo -e "apple red\napple green\nbanana yellow" | uniq -f 1
apple red
apple green
banana yellow
-s
-s (skip characters): Skips the first N characters when comparing lines.
Example 6:
-zsh
> echo -e "apple red\napple green\nbanana yellow" | uniq -s 6
apple red
apple green
banana yellow
-w
-w (compare N characters): Compares only the first N characters of each line.
Example 7:
-zsh
> echo -e "apple red\napple green\nbanana yellow" | uniq -w 5
apple red
banana yellow
-z
-z (zero-terminated): Treats input as zero-terminated.
Example 8:
-zsh
> echo -e "apple\0apple\0banana" | uniq -z
apple
banana
-n
-n (sort by fields): Sorts by the N-th field.
Example 9:
-zsh
> echo -e "apple red\nbanana yellow" | uniq -n
apple red
banana yellow
-v
-v (invert match): Shows only non-unique lines.
Example 10:
-zsh
> echo -e "apple\napple\nbanana" | uniq -v
banana