.h file use c/c++ mode or objc-mode base on it's content, so there is emacswiki solution there: https://www.emacswiki.org/emacs/ObjectiveCMode, so i put the the code in my configuration:
;; header .h add to objc-mode, this cause org unable to export to html file (add-to-list 'magic-mode-alist `(,(lambda () (and (string= (file-name-extension buffer-file-name) "h") (re-search-forward "@\\<interface\\>" magic-mode-regexp-match-limit t))) . objc-mode)) i turn on debug-on-error options:(setq debug-on-error t), and export org file to html by typing: C-c C-e h h, and there is error: Debugger entered--Lisp error: (wrong-type-argument stringp nil) file-name-nondirectory(nil) file-name-extension(nil) (string= (file-name-extension buffer-file-name) "h") (and (string= (file-name-extension buffer-file-name) "h") (re-search-forward "@\\<interface\\>" magic-mode-regexp-match-limit t)) (lambda nil (and (string= (file-name-extension buffer-file-name) "h") (re-search-forward "@\\<interface\\>" magic-mode-regexp-match-limit t)))() #[514 "\300!\203 \207\301!\207" [functionp looking-at] 4 "\n\n(fn RE DUMMY)"]((lambda nil (and (string= (file-name-extension buffer-file-name) "h") (re-search-forward "@\\<interface\\>" magic-mode-regexp-match-limit t))) nil) assoc-default(nil (((lambda nil (and (string= (file-name-extension buffer-file-name) "h") (re-search-forward "@\\<interface\\>" magic-mode-regexp-match-limit t))) . objc-mode) ("^[{[]$" . json-mode)) #[514 "\300!\203 \207\301!\207" [functionp looking-at] 4 "\n\n(fn RE DUMMY)"]) set-auto-mode(t) org-html-final-function(...) ;; some long text i delete to make the mail clean org-export-filter-apply-functions(...) ;; some long text i delete to make the mail clean org-export-as(html nil nil nil (:output-file "study.html")) org-export-to-file(html "study.html" nil nil nil nil nil) org-html-export-to-html(nil nil nil nil) org-export-dispatch(nil) funcall-interactively(org-export-dispatch nil) call-interactively(org-export-dispatch nil nil) command-execute(org-export-dispatch) may be it cause org file unable to convert to other format files too. ------------------------------------------------------------------------ Emacs : GNU Emacs 25.3.1 (x86_64-apple-darwin13.4.0, NS appkit-1265.21 Version 10.9.5 (Build 13F1911)) of 2017-09-13 Package: Org mode version 9.1.5 (9.1.5-1-gb3ddb0-elpa @ /Users/peck/.emacs.d/elpa/org-20171225/) current state: ============== (setq org-hide-leading-stars t org-tab-first-hook '(org-babel-hide-result-toggle-maybe org-babel-header-arg-expand) org-speed-command-hook '(org-speed-command-activate org-babel-speed-command-activate) org-occur-hook '(org-first-headline-recenter) org-metaup-hook '(org-babel-load-in-session-maybe) org-log-done t org-confirm-shell-link-function 'yes-or-no-p org-agenda-custom-commands '(("h" "Daily habits" ((agenda "")) ((org-agenda-show-log t) (org-agenda-ndays-to-span 7) (org-agenda-log-mode-items (quote (state))) (org-agenda-skip-function (quote (org-agenda-skip-entry-if (quote notregexp) ":DAILY:"))) ) ) ("w" . "Task schedule") ("wa" "Important and urgent task" tags-todo "+PRIORITY=\"A\"") ("wb" "Important but not urgent task" tags-todo "-Weekly-Monthly-Daily+PRIORITY=\"B\"") ("wc" "Unimportant and not urgent task" tags-todo "+PRIORITY=\"C\"") ("p" . "Project schedule") ("pw" tags-todo "PROJECT+WORK+CATEGORY=\"c/c++/objc\"") ("pl" tags-todo "PROJECT+DREAM+CATEGORY=\"peckchen\"") ("W" "Weekly Review" ((stuck "") (tags-todo "PROJECT")))) org-after-todo-state-change-hook '(org-clock-out-if-current) org-src-mode-hook '(org-src-babel-configure-edit-buffer org-src-mode-configure-edit-buffer) org-agenda-before-write-hook '(org-agenda-add-entry-text) org-babel-pre-tangle-hook '(save-buffer) org-font-lock-set-keywords-hook '(doom-org-custom-fontification) org-mode-hook '((lambda nil (org-bullets-mode 1)) (lambda nil (company-mode) (local-set-key "w" (quote org-pomodoro))) #[0 "\300\301\302\303\304$\207" [add-hook change-major-mode-hook org-show-block-all append local] 5] #[0 "\300\301\302\303\304$\207" [add-hook change-major-mode-hook org-babel-show-result-all append local] 5] org-babel-result-hide-spec org-babel-hide-all-hashes) org-fontify-done-headline t org-bibtex-headline-format-function #[257 "\300\236A\207" [:title] 3 "\n\n(fn ENTRY)"] org-archive-hook '(org-attach-archive-delete-maybe) org-pomodoro-ticking-sound "/Users/peck/.emacs.d/elpa/org-pomodoro-20171108.1314/resources/tick.wav" org-cycle-hook '(org-cycle-hide-archived-subtrees org-cycle-hide-drawers org-cycle-show-empty-lines org-optimize-window-after-visibility-change) org-load-hook '(doom-org-default-settings) org-fontify-quote-and-verse-blocks t org-pomodoro-start-sound "/Users/peck/.emacs.d/elpa/org-pomodoro-20171108.1314/resources/bell.wav" org-confirm-elisp-link-function 'yes-or-no-p org-metadown-hook '(org-babel-pop-to-session-maybe) org-link-parameters '(("id" :follow org-id-open) ("rmail" :follow org-rmail-open :store org-rmail-store-link) ("mhe" :follow org-mhe-open :store org-mhe-store-link) ("irc" :follow org-irc-visit :store org-irc-store-link) ("info" :follow org-info-open :export org-info-export :store org-info-store-link) ("gnus" :follow org-gnus-open :store org-gnus-store-link) ("docview" :follow org-docview-open :export org-docview-export :store org-docview-store-link) ("bibtex" :follow org-bibtex-open :store org-bibtex-store-link) ("bbdb" :follow org-bbdb-open :export org-bbdb-export :complete org-bbdb-complete-link :store org-bbdb-store-link) ("w3m" :store org-w3m-store-link) ("file+sys") ("file+emacs") ("doi" :follow org--open-doi-link) ("elisp" :follow org--open-elisp-link) ("file" :complete org-file-complete-link) ("ftp" :follow (lambda (path) (browse-url (concat "ftp:" path)))) ("help" :follow org--open-help-link) ("http" :follow (lambda (path) (browse-url (concat "http:" path)))) ("https" :follow (lambda (path) (browse-url (concat "https:" path)))) ("mailto" :follow (lambda (path) (browse-url (concat "mailto:" path)))) ("news" :follow (lambda (path) (browse-url (concat "news:" path)))) ("shell" :follow org--open-shell-link)) org-pomodoro-long-break-sound "/Users/peck/.emacs.d/elpa/org-pomodoro-20171108.1314/resources/bell_multiple.wav" org-pomodoro-finished-sound "/Users/peck/.emacs.d/elpa/org-pomodoro-20171108.1314/resources/bell.wav" org-pomodoro-short-break-sound "/Users/peck/.emacs.d/elpa/org-pomodoro-20171108.1314/resources/bell.wav" org-fontify-whole-heading-line t org-agenda-files '("~/org/study.org" "~/org/work.org" "~/org/daily.org" "~/org/issue.org") org-clock-out-hook '(org-clock-remove-empty-clock-drawer) ) -- Best regards Peck Chen / 陈泼杨