difference between the content of two files

Question

I have two files one file subset of other and i want to obtain a file which has contents not common to both.for example

File1

apple
mango
banana
orange
jackfruit
cherry
grapes
eggplant
okra
cabbage

File2

apple
banana
cherry
eggplant
cabbage

The resultant file, difference of above two files

mango
orange
jackfruit
grapes
okra

Any ideas on this are appreciated.

Answer 1

You can sort the files then use comm:

$ comm -23 <(sort file1.txt) <(sort file2.txt)
grapes
jackfruit
mango
okra
orange

You might also want to use comm -3 instead of comm -23:

  -1              suppress lines unique to FILE1
  -2              suppress lines unique to FILE2
  -3              suppress lines that appear in both files

Answer 2

use awk, no sorting necessary (reduce overheads)

$ awk 'FNR==NR{f[$1];next}(!($1 in f)) ' file2 file
mango
orange
jackfruit
grapes
okra

Answer 3

1 Only one instance , in either

• cat File1 File2 | sort | uniq -u

2 Only in first file

• cat File1 File2 File2 | sort | uniq -u

3 Only in second file

• cat File1 File1 File2 | sort | uniq -u