Displays difference of 2 files in same console.
Here "<" represents unique lines in dir1.txt and ">"
represents unique lines in dir2.txt.
# diff -y dir1.txt dir2.txt
In below example the sum of unique entries in dir1.txt is listed.
# diff -y dir1.txt dir2.txt | grep "<" | wc -l
comm command usage:
Here its necessary to have both files sorted.
# sort file1
# sort file2
# comm -23 file1 file2
displays lines unique in file1 -23
displays lines unique in file2 -13
displays lines unique in both file1 and file2, 2 coloumns
in same console -3
displays lines common in both files -12