A full permission mode consists of the three permissions for each of the three communities. In addition, there may be some Extended Permissions (see below).

A permission may be represented as a string of nine r, w, x, and - characters. The first three characters represent the permissions for the user, the second set of three represent the permissions for the group, and the last three represent the permissions for others. Each group consists of the letters r, w, and x in order for permissions that are turned on, or - for permissions that are not turned on.j