It is used to skip N fields before detecting the uniqueness of data. Fields are the group of characters separated by whitespace or tab.<\/p>\n
- \n
- -s N or \u2013skip-chars=N<\/li>\n<\/ul>\n
It is used to skip N characters before detecting the uniqueness of data.<\/p>\n
- \n
- -w N or \u2013check-chars=N<\/li>\n<\/ul>\n
It is used to compare N characters only in a line.<\/p>\n
- \n
- -c or \u2013count<\/li>\n<\/ul>\n
It is used to count how many times a line repeated in the searching data and the values are shown as the prefix of that line.<\/p>\n
- \n
- -z or \u2013zero-terminated<\/li>\n<\/ul>\n
It is used to terminate the line with 0 bytes instead of using newline.<\/p>\n
- \n
- -d or \u2013repeated<\/li>\n<\/ul>\n
It is used to print all repeated lines only.<\/p>\n
- \n
- -D or \u2013all-repeated[=METHOD]<\/li>\n<\/ul>\n
It is used to print all repeated lines based on the used method. The following methods can be used with this option.<\/p>\n
none: It is the default method and doesn\u2019t delimit duplicate lines.
\nprepend: It adds a blank line before each set of duplicate lines.
\nseparate: It adds a blank line between two duplicate lines.<\/p>\n- \n
- -u or \u2013unique<\/li>\n<\/ul>\n
It is used to print the unique lines only.<\/p>\n
- \n
- -i or \u2013ignore-case<\/li>\n<\/ul>\n
It is used for case-insensitive comparison.<\/p>\n
Examples of uniq command<\/h3>\n
Create a text file named uniq_test.txt with the following content:<\/p>\n
Bash Programming
\nBash Programming
\nPython Programming
\nI like PHP Programming
\nI like Java Programming<\/p>\nExample#1: Using -f option<\/h3>\n
The following command will apply uniq command by skipping first two fields of each line from uniq_test.txt file.<\/p>\n
$ uniq -f 2 uniq_test.txt<\/p>\n
![\"\"](\"https:\/\/linuxhint.com\/wp-content\/uploads\/2018\/12\/1-40.png\")
<\/p>\nExample#2: Using -s option<\/h3>\n
The following command will apply uniq command by skipping 4 characters from each line of uniq_test.txt file.<\/p>\n
$ uniq -s 4 uniq_test.txt<\/p>\n
![\"\"](\"https:\/\/linuxhint.com\/wp-content\/uploads\/2018\/12\/2-36.png\")
<\/p>\nExample#3: Using \u2013w option<\/h3>\n
The following command will apply uniq command by comparing the first two characters of each line.<\/p>\n
$ uniq -w 2 uniq_test.txt<\/p>\n
![\"\"](\"https:\/\/linuxhint.com\/wp-content\/uploads\/2018\/12\/3-35.png\")
<\/p>\nExample#4: Using \u2013c option<\/h3>\n
The following command will count the appearance of each line in the file and displays the number at the front of each line of the output.<\/p>\n
![\"\"](\"https:\/\/linuxhint.com\/wp-content\/uploads\/2018\/12\/4-34.png\")
<\/p>\nExample#5: Using \u2013d option<\/h3>\n
The following command displays those lines from the file only that appeared multiple times in the file. Only one line has appeared two times in uniq_test.txt file which is displayed as output.<\/p>\n
![\"\"](\"https:\/\/linuxhint.com\/wp-content\/uploads\/2018\/12\/5-36.png\")
<\/p>\nExample#6: Using \u2013D option<\/h3>\n
The following command will print all duplicate lines from the file.<\/p>\n
![\"\"](\"https:\/\/linuxhint.com\/wp-content\/uploads\/2018\/12\/6-32.png\")
<\/p>\nExample#7: Using \u2013all-repeated option with prepend method<\/h3>\n
Three methods can be used with \u2013all-repeated option which are mentioned earlier of this tutorial. Here, the prepend method is used with this option that prints duplicate lines by appending blank lines at the beginning of duplicate lines.<\/p>\n
$ uniq –all-repeated=prepend uniq_test.txt<\/p>\n
![\"\"](\"https:\/\/linuxhint.com\/wp-content\/uploads\/2018\/12\/7-33.png\")
<\/p>\nExample#8: Using \u2013u option<\/h3>\n
The following command will find out all the unique lines from the file. There are three unique lines in uniq_test.txt file which are printed as output.<\/p>\n
![\"\"](\"https:\/\/linuxhint.com\/wp-content\/uploads\/2018\/12\/8-30.png\")
<\/p>\nConclusion<\/h4>\n
The uses of uniq command are explained and shown by using various examples in this tutorial. Hope, you will be able to use uniq command properly after reading this tutorial.<\/p>\n
- -i or \u2013ignore-case<\/li>\n<\/ul>\n
- -u or \u2013unique<\/li>\n<\/ul>\n
- -D or \u2013all-repeated[=METHOD]<\/li>\n<\/ul>\n
- -d or \u2013repeated<\/li>\n<\/ul>\n
- -z or \u2013zero-terminated<\/li>\n<\/ul>\n
- -c or \u2013count<\/li>\n<\/ul>\n
- -w N or \u2013check-chars=N<\/li>\n<\/ul>\n