NAME

comm − select or reject lines common to two sorted files

SYNOPSIS

comm [ − [ 123 ] ] file1 file2

DESCRIPTION

Comm reads file1 and file2, which should be ordered in ASCII collating sequence, and produces a three column output: lines only in file1; lines only in file2; and lines in both files.  The filename ‘−’ means the standard input. 

Flags 1, 2, or 3 suppress printing of the corresponding column.  Thus comm −12 prints only the lines common to the two files; comm −23 prints only lines in the first file but not in the second; comm −123 is a no-op. 

SEE ALSO

cmp(1), diff(1), uniq(1)

7th Edition  —  April 29, 1985