Boolean Difference between text files on Linux?

Question

Are there any command line linux utilities that will give me the boolean difference between two text files?

Meaning:

File-A:

Apple  
Pear  
Orange   
Banana

File-B:

Pear  
Orange

Running

% program File-A File-B -o output

output:

Apple  
Banana

Edit:

Awesome, thanks guys!

Could there be items in file2 that are not in file1? If not, why do you call it the 'boolean difference'? — Mark Byers, Jan 31 '10 at 16:44

score 3 · Accepted Answer · answered Jan 31 '10 at 16:40

3

Like this:

comm -2 -3 File-A File-B > output

This assumes that the files are sorted. Check man comm for more information.

answered Jan 31 '10 at 16:40

Thomas

1

To sort them (bash syntax): `comm -3 <(sort -u File-A) <(sort -u File-B)` – Tobu Jan 31 '10 at 16:48

score 1 · Answer 2 · answered Jan 31 '10 at 16:38

1

The comm command is what you want here.

answered Jan 31 '10 at 16:38

bmargulies

score 0 · Answer 3 · answered Jan 31 '10 at 16:45

0

Try this:

comm -3 file1.txt file2.txt | sed -r 's/^\t//'

This also catches items in file2 that are not in file 1.

answered Jan 31 '10 at 16:45

Mark Byers

3 Answers3