Gentlemen, is there a quick way to select lines that are duplicated in 2 files?
At the exit you need to get
Any compact and fast solution, maybe through diff?
You can use the
join command. She perfectly solves the task, although she can do more.
join file1.txt file2.txt
The command will issue a warning that you should first sort the files and lines found in both files
:~> join file1.txt file2.txt join: file 2 is not in sorted orderjoin: file 1 is not in sorted orderMariaIvan
Addition (as suggested by PocketSam ): Files can be sorted with the
sort command. The next line sorts one of the files, merges and deletes the temporary file.
:~> FILE2=$( mktemp ) && sort file2.txt > $FILE2 && \sort file1.txt | join - $FILE2 && rm $FILE2