+
+ (require 'dired-x)
+ (setq dired-guess-shell-alist-user
+ '(("\\.pdf\\'" "evince" "zathura" "okular")
+ ("\\.doc\\'" "libreoffice")
+ ("\\.docx\\'" "libreoffice")
+ ("\\.ppt\\'" "libreoffice")
+ ("\\.pptx\\'" "libreoffice")
+ ("\\.xls\\'" "libreoffice")
+ ("\\.xlsx\\'" "libreoffice")
+ ("\\.flac\\'" "mpv")))