[Org] A custom link type for RFCs

init.el

@@ -569,7 +569,8 @@ search commands like `db/helm-shortcuts’."
              db/bookmark-add-url
              db/lookup-smime-key
              db/org-onenote-open
-             db/org-outlook-open))
+             db/org-outlook-open
+             db/org-rfc-open))
 
 (use-package hydra
   :commands (defhydra))
@@ -782,6 +783,9 @@ search commands like `db/helm-shortcuts’."
             ;; Skip some org mode regions to be skipped by ispell
             (add-hook 'org-mode-hook #'endless/org-ispell)
 
+            ;; Link type for RFCs
+            (org-link-set-parameters "rfc" :follow #'db/org-rfc-open)
+
             ;; Some timers
 
             (unless (memq #'org-clock-save

site-lisp/db-utils.el

@@ -519,6 +519,13 @@ This is done only if the value of this variable is not null."
   (unless (file-executable-p db/path-to-outlook)
     (user-error "Path for Outlook is not executable, please customize `db/path-to-outlook’."))
   (w32-shell-execute "open" db/path-to-outlook (concat "/select outlook:" id)))
+
+(defun db/org-rfc-open (number)
+  "Open browser to show RFC of given NUMBER."
+  (unless (string-match "[1-9][0-9]*" number)
+    (user-error "Not a valid number for an RFC: %s" number))
+  (browse-url (concat "https://tools.ietf.org/html/rfc" number)))
+
 
 ;;; Bookmarks