buffer-face-mode-invoke is a compiled Lisp function in `face-remap.el'.

(buffer-face-mode-invoke SPECS ARG &optional INTERACTIVE)

Enable or disable `buffer-face-mode' using face specs SPECS.
ARG controls whether the mode is enabled or disabled, and is
interpreted in the usual manner for minor-mode commands.

SPECS can be any value suitable for a `face' text property,
including a face name, a plist of face attributes and values,
or a list of faces.

If INTERACTIVE is non-nil, display a message describing the

This is a wrapper function which calls `buffer-face-set' or
`buffer-face-toggle' (depending on ARG), and prints a status
message in the echo area. In many cases one of those functions
may be more appropriate.