[shepherd] Fix init file

‘current-filename’ is the real file name of the file, not the symbolic link that
it's accessed through, so any relative references will be wrong.

shepherd/.config/shepherd/init.scm.org

@@ -1,13 +1,28 @@
 [[info:shepherd][The Shepherd manual]] suggests that you use a single =init.scm=, but as is pointed out by this article about [[https://guix.gnu.org/en/blog/2020/gnu-shepherd-user-services/][GNU Shepherd user services]] it might be better to have the services in separate files so you can restart them individually if you make any changes to them. So I just put a loading script into =init.scm= that goes through the =init.d= directory and loads each service defined in there.
 
 #+begin_src scheme
-(use-modules (shepherd service)
+  (use-modules (shepherd service)
                ((ice-9 ftw) #:select (scandir)))
-
-(for-each
- (λ (file) (load (string-append "init.d/" file)))
- (scandir (string-append (dirname (current-filename)) "/init.d")
-          (λ (file) (string-suffix? ".scm" file))))
-
-(action 'shepherd 'daemonize)
+#+end_src
+
+I can't use ~(current-filename)~ here because this file will be symlinked into the =$XDG_CONFIG_DIR/shepherd/init.scm= and the =current-filename= function will return the actual path, not the path of the symbolic link.
+
+#+begin_src scheme
+  (define init-directory
+    (string-append (getenv "XDG_CONFIG_HOME") "/shepherd/init.d"))
+#+end_src
+
+With that in place, we can loop over each =*.scm= file in the =init-directory= and load them.
+
+#+begin_src scheme
+  (for-each
+   (λ (file) (load (string-append "init.d/" file)))
+   (scandir init-directory
+            (λ (file) (string-suffix? ".scm" file))))
+#+end_src
+
+Now turn shepherd into a daemon.
+
+#+begin_src scheme
+  (action 'shepherd 'daemonize)
 #+end_src