Variable: face-font-family-alternatives
face-font-family-alternatives is a customizable variable defined in
faces.el.gz.
Value
(("Monospace" "courier" "fixed")
("Monospace Serif" "Courier 10 Pitch" "Consolas" "Courier Std" "FreeMono" "Nimbus Mono L" "courier" "fixed")
("courier" "CMU Typewriter Text" "fixed")
("Sans Serif" "helv" "helvetica" "arial" "fixed")
("helv" "helvetica" "arial" "fixed"))
Documentation
Alist of alternative font family names.
Each element has the form (FAMILY ALTERNATIVE1 ALTERNATIVE2 ...). If fonts of family FAMILY can't be loaded, try ALTERNATIVE1, then ALTERNATIVE2 etc.
Probably introduced at or before Emacs version 21.1.
Source Code
;; Defined in /usr/src/emacs/lisp/faces.el.gz
;; In the absence of Fontconfig support, Monospace and Sans Serif are
;; unavailable, and we fall back on the courier and helv families,
;; which are generally available.
(defcustom face-font-family-alternatives
(mapcar (lambda (arg) (mapcar 'purecopy arg))
'(("Monospace" "courier" "fixed")
;; Monospace Serif is an Emacs invention, intended to work around
;; portability problems when using Courier. It should work well
;; when combined with Monospaced and with other standard fonts.
;; One of its uses is for 'tex-verbatim' and 'Info-quoted' faces,
;; so the result must be different from the default face's font,
;; and must be monospaced. For 'tex-verbatim', it is desirable
;; that the font really is a Serif font, so as to look like
;; TeX's 'verbatim'.
("Monospace Serif"
;; This looks good on GNU/Linux.
"Courier 10 Pitch"
;; This looks good on MS-Windows and OS X. Note that this is
;; actually a sans-serif font, but it's here for lack of a better
;; alternative.
"Consolas"
;; This looks good on macOS. "Courier" looks good too, but is
;; jagged on GNU/Linux and so is listed later as "courier".
"Courier Std"
;; Although these are anti-aliased, they are a bit faint compared
;; to the above.
"FreeMono" "Nimbus Mono L"
;; These are aliased and look jagged.
"courier" "fixed"
;; Omit Courier New, as it is the default MS-Windows font and so
;; would look no different, and is pretty faint on other platforms.
)
;; This is present for backward compatibility.
("courier" "CMU Typewriter Text" "fixed")
("Sans Serif" "helv" "helvetica" "arial" "fixed")
("helv" "helvetica" "arial" "fixed")))
"Alist of alternative font family names.
Each element has the form (FAMILY ALTERNATIVE1 ALTERNATIVE2 ...).
If fonts of family FAMILY can't be loaded, try ALTERNATIVE1, then
ALTERNATIVE2 etc."
:tag "Alternative font families to try"
:type '(repeat (repeat string))
:group 'font-selection
:set #'(lambda (symbol value)
(set-default symbol value)
(internal-set-alternative-font-family-alist value)))