comm

The command in the Unix family of computer operating systems is a utility that is used to compare two files for common and distinct lines. is specified in the POSIX standard. It has been widely available on Unix-like operating systems since the mid to late 1980s. History Written by Lee E. McMahon, first appeared in Version 4 Unix. The version of bundled in GNU coreutils was written by Richard Stallman and David MacKenzie. Usage reads two files as input, regarded as lines of text. outputs one file, which contains three columns. The first two columns contain lines unique to the first and second file, respectively. The last column contains lines common to both. This functionally is similar to .