Perform set operations on lines of two files. The order of the output lines is determined by the order of the lines in the first file. See also:
diff
. More information: https://joeyh.name/code/moreutils/.
combine path/to/file1 and path/to/file2
combine path/to/file1 not path/to/file2
combine path/to/file1 or path/to/file2
combine path/to/file1 xor path/to/file2