1.0 comm
The comm command compares two sorted files and gives output in three columns. The first column has lines which are present only in the first file. The second column contains lines which are present only in the second file. The third column gives the lines which are common to both files. For example,
$ cat names Alan Bloggs Erika Mustermann James Bond Jane Doe Jimmy Fernandes Joe Bloggs John Doe John Roe Max Mustermann Richard Roe Tommy Atkins $ $ cat fames Alice Newman Erika Mustermann Jane Doe Jimmy Doe Joe Bloggs John Doe John Roe Max Mustermann Richard Roe Tommy Atkins Tom Roe $ $ comm names fames Alan Bloggs Alice Newman Erika Mustermann James Bond Jane Doe Jimmy Doe Jimmy Fernandes Joe Bloggs John Doe John Roe Max Mustermann Richard Roe Tommy Atkins Tom Roe
It is possible to suppress printing of one or more columns by passing the column number as an argument.
$ # Suppress printing of the first column $ comm -1 names fames Alice Newman Erika Mustermann Jane Doe Jimmy Doe Joe Bloggs John Doe John Roe Max Mustermann Richard Roe Tommy Atkins Tom Roe $ $ # Suppress printing of the first and second columns $ comm -12 names fames Erika Mustermann Jane Doe Joe Bloggs John Doe John Roe Max Mustermann Richard Roe Tommy Atkins
