Man Pages – Linux Manual Pages

diff3 – find differences between three files
USAGE
diff3 [options] mine older yours

DESCRIPTION
The diff3 command compares three files and outputs descriptions of
their differences.

The files [...]

diff – find differences between two files
USAGE
diff [options] from-file to-file

DESCRIPTION
In the simplest case, diff compares the contents of the two files from-
file and to-file. A file name of – stands for text read [...]

comm – compare two sorted files line by line
USAGE
comm [OPTION]… LEFT_FILE RIGHT_FILE

DESCRIPTION
Compare sorted files LEFT_FILE and RIGHT_FILE line by line.

-1 suppress lines unique to left file

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