Permissions.Constructor(FolderItem.Permissions as Integer)
From Xojo Documentation
Creates a Permissions instance with the passed permissions. The value is base 8 and can be specified using the octal keyword (&o).
See the Notes section for Permissions and the FolderItem.Permissions entry for the tables used to set the octal value of permissions. Pass the octal value that corresponds to the desired permissions level. You can also pass a zero and then assign permissions. This is shown in the first example of the Permissions class.
The following example gives the owner Read, Write and Execute privileges: