The Empty Backend

nnnil is a backend that can be used as a placeholder if you have to specify a backend somewhere, but don’t really want to. The classical example is if you don’t want to have a primary select methods, but want to only use secondary ones:

(setq gnus-select-method '(nnnil ""))
(setq gnus-secondary-select-methods
      '((nnimap "foo")
        (nnml "")))