emacs org-mode 导出 odt 文件，但使用 PDF 查看器打开

Question

由于某种原因 org-mode 正确导出到 ODT 文件，但使用默认 PDF 查看器 (okular) 而不是 libreoffice 打开它。我已经尝试了类似post 中提到的所有解决方案，但没有任何运气。作为参考，我在我的初始化文件的相关部分下面复制。我的 emacs 是 27.0.50，我的 org-mode 是 9.1.13。

;; Enable export in ODT format
(eval-after-load "org" '(require 'ox-odt nil t)) ; enable odt backend
;; Open ODT files with libre office
(defun my-org-export-to-odt-and-open ()
  (interactive)
  (org-open-file (org-odt-export-to-odt)))

在我的自定义设置变量中，我有

 '(org-file-apps
   '((auto-mode . emacs)
     ("\\.mm\\'" . default)
     ("\\.x?html?\\'" . default)
     ("\\.odt\\'" . "libreoffice %s") 
     ("\\.pdf\\'" . "okular %s")))

提前感谢您的帮助。

这是 org-file-apps 的输出值

Value:
((auto-mode . emacs)
 ("\\.mm\\'" . default)
 ("\\.x?html?\\'" . default)
 ("\\.odt\\'" . "libreoffice %s")
 ("\\.pdf\\'" . "okular %s"))
Original value was 
((auto-mode . emacs)
 ("\\.mm\\'" . default)
 ("\\.x?html?\\'" . default)
 ("\\.pdf\\'" . default))

这是我尝试导出 NOTES.org 文件时 org-open-file 上的 edebug 的一个输出。

Debugger entered--returning value: nil
  string-match("\\$\\(?:\\(?1:[[:alnum:]_]+\\)\\|{\\(?1:[^{}]+\\)}\\|\\$\\)" "/home/andre/org/NOTES.odt" 0)
* substitute-env-vars("/home/andre/org/NOTES.odt" t)
* substitute-env-in-file-name("/home/andre/org/NOTES.odt")
* substitute-in-file-name("/home/andre/org/NOTES.odt")
* #f(compiled-function (path &optional in-emacs line search) "Open the file at PATH.\nFirst, this expands any special file name abbreviations.  Then the\nconfiguration variable `org-file-apps' is checked if it contains an\nentry for this file type, and if yes, the corresponding command is launched.\n\nIf no application is found, Emacs simply visits the file.\n\nWith optional prefix argument IN-EMACS, Emacs will visit the file.\nWith a double \\[universal-argument] \\[universal-argument] prefix arg, Org tries to avoid opening in Emacs\nand to use an external application to visit the file.\n\nOptional LINE specifies a line to go to, optional SEARCH a string\nto search for.  If LINE or SEARCH is given, the file will be\nopened in Emacs, unless an entry from org-file-apps that makes\nuse of groups in a regexp matches.\n\nIf you want to change the way frames are used when following a\nlink, please customize `org-link-frame-setup'.\n\nIf the file does not exist, an error is thrown." #<bytecode 0x1524219>)("NOTES.odt" system)
* apply(#f(compiled-function (path &optional in-emacs line search) "Open the file at PATH.\nFirst, this expands any special file name abbreviations.  Then the\nconfiguration variable `org-file-apps' is checked if it contains an\nentry for this file type, and if yes, the corresponding command is launched.\n\nIf no application is found, Emacs simply visits the file.\n\nWith optional prefix argument IN-EMACS, Emacs will visit the file.\nWith a double \\[universal-argument] \\[universal-argument] prefix arg, Org tries to avoid opening in Emacs\nand to use an external application to visit the file.\n\nOptional LINE specifies a line to go to, optional SEARCH a string\nto search for.  If LINE or SEARCH is given, the file will be\nopened in Emacs, unless an entry from org-file-apps that makes\nuse of groups in a regexp matches.\n\nIf you want to change the way frames are used when following a\nlink, please customize `org-link-frame-setup'.\n\nIf the file does not exist, an error is thrown." #<bytecode 0x1524219>) ("NOTES.odt" system))
* org-open-file("NOTES.odt" system)
  (if a (org-odt-export-to-odt t s v) (org-open-file (org-odt-export-to-odt nil s v) 'system))
  (lambda (a s v b) (if a (org-odt-export-to-odt t s v) (org-open-file (org-odt-export-to-odt nil s v) 'system)))(nil t nil nil)
  org-export-dispatch(nil)
  funcall-interactively(org-export-dispatch nil)
  call-interactively(org-export-dispatch nil nil)
  command-execute(org-export-dispatch)

我一直往前走，直到下图所示的点。看起来文件匹配为\\.mm\\?

Debugger entered--returning value: (10578 10582)
  match-data()
* regexp-opt-depth("\\.mm\\'")
* org-file-apps-entry-match-against-dlink-p(("\\.mm\\'" . default))
* cl-remove(nil ((auto-mode . emacs) ("\\.mm\\'" . default) ("\\.x?html?\\'" . default) ("\\.odt\\'" . "libreoffice %s") ("\\.pdf\\'" . "okular %s") (remote . emacs) (system . mailcap) (t . mailcap)) :if org-file-apps-entry-match-against-dlink-p)
* apply(cl-remove nil ((auto-mode . emacs) ("\\.mm\\'" . default) ("\\.x?html?\\'" . default) ("\\.odt\\'" . "libreoffice %s") ("\\.pdf\\'" . "okular %s") (remote . emacs) (system . mailcap) (t . mailcap)) :if org-file-apps-entry-match-against-dlink-p nil)
* cl-remove-if(org-file-apps-entry-match-against-dlink-p ((auto-mode . emacs) ("\\.mm\\'" . default) ("\\.x?html?\\'" . default) ("\\.odt\\'" . "libreoffice %s") ("\\.pdf\\'" . "okular %s") (remote . emacs) (system . mailcap) (t . mailcap)))
* #f(compiled-function (path &optional in-emacs line search) "Open the file at PATH.\nFirst, this expands any special file name abbreviations.  Then the\nconfiguration variable `org-file-apps' is checked if it contains an\nentry for this file type, and if yes, the corresponding command is launched.\n\nIf no application is found, Emacs simply visits the file.\n\nWith optional prefix argument IN-EMACS, Emacs will visit the file.\nWith a double \\[universal-argument] \\[universal-argument] prefix arg, Org tries to avoid opening in Emacs\nand to use an external application to visit the file.\n\nOptional LINE specifies a line to go to, optional SEARCH a string\nto search for.  If LINE or SEARCH is given, the file will be\nopened in Emacs, unless an entry from org-file-apps that makes\nuse of groups in a regexp matches.\n\nIf you want to change the way frames are used when following a\nlink, please customize `org-link-frame-setup'.\n\nIf the file does not exist, an error is thrown." #<bytecode 0x1524219>)("NOTES.odt" system)
* apply(#f(compiled-function (path &optional in-emacs line search) "Open the file at PATH.\nFirst, this expands any special file name abbreviations.  Then the\nconfiguration variable `org-file-apps' is checked if it contains an\nentry for this file type, and if yes, the corresponding command is launched.\n\nIf no application is found, Emacs simply visits the file.\n\nWith optional prefix argument IN-EMACS, Emacs will visit the file.\nWith a double \\[universal-argument] \\[universal-argument] prefix arg, Org tries to avoid opening in Emacs\nand to use an external application to visit the file.\n\nOptional LINE specifies a line to go to, optional SEARCH a string\nto search for.  If LINE or SEARCH is given, the file will be\nopened in Emacs, unless an entry from org-file-apps that makes\nuse of groups in a regexp matches.\n\nIf you want to change the way frames are used when following a\nlink, please customize `org-link-frame-setup'.\n\nIf the file does not exist, an error is thrown." #<bytecode 0x1524219>) ("NOTES.odt" system))
* org-open-file("NOTES.odt" system)
  (if a (org-odt-export-to-odt t s v) (org-open-file (org-odt-export-to-odt nil s v) 'system))
  (lambda (a s v b) (if a (org-odt-export-to-odt t s v) (org-open-file (org-odt-export-to-odt nil s v) 'system)))(nil t nil nil)
  org-export-dispatch(nil)
  funcall-interactively(org-export-dispatch nil)
  call-interactively(org-export-dispatch nil nil)
  command-execute(org-export-dispatch)

实际上，我一直在前进，并且没有与 org-file-apps 中可用的任何选项相匹配。

Answer 1

经过大量挖掘，我发现了这些帖子：post1post2 从中出现了以下解决方案：

;; Enable export in ODT format
(setcdr (assq 'system org-file-apps-defaults-gnu ) "xdg-open %s")
(setq process-connection-type nil)

在 org-file-apps 上没有任何配置。