How Do I Find Duplicates in a Text File in Unix?

To search for duplicate files using fdupes, we type: fdupes -r . And to search duplicates with jdupes: jdupes -r .

How do I find duplicate records in a text file in Unix?

Let us now see the different ways to find the duplicate record.

1. Using sort and uniq: $ sort file | uniq -d Linux. …
2. awk way of fetching duplicate lines: $ awk ‘{a[$0]++}END{for (i in a)if (a[i]>1)print i;}’ file Linux. …
3. Using perl way: …
4. Another perl way: …
5. A shell script to fetch / find duplicate records:

How do I find duplicates in a text file?

Count Repeated Lines

To output the number of repeated lines in a text file, use the -c flag with the default command. The system displays the count of each line that exists in the text file. You can see that the line This is a text file occurs two times in the file. By default, the uniq command is case-sensitive.