`find-file-noselect-as-coding-system' with CODING-SYSTEM as the 1st arg.
* gnus-score.el (gnus-score-load-score-alist): Call
`insert-file-contents-as-coding-system' with CODING-SYSTEM as the 1st arg.
* nnmail.el (nnmail-find-file): Ditto.
* nnheader.el (nnheader-insert-file-contents): Ditto.
* score-mode.el (gnus-score-edit-exit): Call `write-region-as-coding-system'
as the 1st arg.
* gnus-start.el (gnus-save-newsrc-file): Ditto.
* gnus-start.el (gnus-read-newsrc-el-file): Call
`insert-file-contents-as-coding-system' with CODING-SYSTEM as the 1st arg.
* gnus-score.el (gnus-score-save): Call `gnus-write-buffer-as-coding-system'
with CODING-SYSTEM as the 1st arg.
* gnus-cache.el (gnus-cache-possibly-enter-article): Ditto.
(gnus-cache-save-buffers): Ditto.
* gnus-util.el (gnus-write-buffer-as-coding-system): Be CODING-SYSTEM the 1st
arg.
* nnmail.el (nnmail-write-region): Call `write-region-as-coding-system' as the
1st arg.
* gnus-agent.el (gnus-agent-expire): Ditto.
(gnus-agent-fetch-headers): Ditto.
(gnus-agent-flush-cache): Ditto.
(gnus-agent-fetch-articles): Ditto.
(gnus-agent-save-history): Ditto.
(gnus-agent-save-groups): Ditto.
(gnus-agent-save-active): Ditto.
           (file (gnus-agent-lib-file "active")))
       (gnus-make-directory (file-name-directory file))
       (write-region-as-coding-system
-       (point-min) (point-max) file gnus-agent-file-coding-system
-       nil 'silent)
+       gnus-agent-file-coding-system (point-min) (point-max) file nil 'silent)
       (when (file-exists-p (gnus-agent-lib-file "groups"))
        (delete-file (gnus-agent-lib-file "groups"))))))
 
         (file (gnus-agent-lib-file "groups")))
     (gnus-make-directory (file-name-directory file))
     (write-region-as-coding-system
-     (point-min) (point-max) file gnus-agent-file-coding-system
-     nil 'silent)
+     gnus-agent-file-coding-system (point-min) (point-max) file nil 'silent)
     (when (file-exists-p (gnus-agent-lib-file "active"))
       (delete-file (gnus-agent-lib-file "active")))))
 
     (set-buffer gnus-agent-current-history)
     (gnus-make-directory (file-name-directory gnus-agent-file-name))
     (write-region-as-coding-system
-     (1+ (point-min)) (point-max) gnus-agent-file-name
-     gnus-agent-file-coding-system nil 'silent)))
+     gnus-agent-file-coding-system
+     (1+ (point-min)) (point-max) gnus-agent-file-name nil 'silent)))
 
 (defun gnus-agent-close-history ()
   (when (gnus-buffer-live-p gnus-agent-current-history)
                (setq id "No-Message-ID-in-article")
              (setq id (buffer-substring (match-beginning 1) (match-end 1))))
            (write-region-as-coding-system
+            gnus-agent-file-coding-system
             (point-min) (point-max)
-            (concat dir (number-to-string (caar pos)))
-            gnus-agent-file-coding-system nil 'silent)
+            (concat dir (number-to-string (caar pos))) nil 'silent)
            (when (setq elem (assq (caar pos) gnus-agent-article-alist))
              (setcdr elem t))
            (gnus-agent-enter-history
     (while gnus-agent-buffer-alist
       (set-buffer (cdar gnus-agent-buffer-alist))
       (write-region-as-coding-system
+       gnus-agent-file-coding-system
        (point-min) (point-max)
        (gnus-agent-article-name ".overview"
                                (caar gnus-agent-buffer-alist))
-       gnus-agent-file-coding-system nil 'silent)
+       nil 'silent)
       (pop gnus-agent-buffer-alist))
     (while gnus-agent-group-alist
       (with-temp-file (caar gnus-agent-group-alist)
        (when (file-exists-p file)
          (gnus-agent-braid-nov group articles file))
        (write-region-as-coding-system
-        (point-min) (point-max) file gnus-agent-file-coding-system
-        nil 'silent)
+        gnus-agent-file-coding-system
+        (point-min) (point-max) file nil 'silent)
        (gnus-agent-save-alist group articles nil)
        (gnus-agent-enter-history
         "last-header-fetched-for-session"
                 (push (cdr elem) histories)))
             (gnus-make-directory (file-name-directory nov-file))
             (write-region-as-coding-system
-             (point-min) (point-max) nov-file gnus-agent-file-coding-system
-             nil 'silent)
+             gnus-agent-file-coding-system
+             (point-min) (point-max) nov-file nil 'silent)
             ;; Delete the unwanted entries in the alist.
             (setq gnus-agent-article-alist
                   (sort gnus-agent-article-alist 'car-less-than-car))
 
          (if (> (buffer-size) 0)
              ;; Non-empty overview, write it to a file.
              (gnus-write-buffer-as-coding-system
-              overview-file gnus-cache-overview-coding-system)
+              gnus-cache-overview-coding-system overview-file)
            ;; Empty overview file, remove it
            (when (file-exists-p overview-file)
              (delete-file overview-file))
              (gnus-request-article-this-buffer number group))
            (when (> (buffer-size) 0)
              (gnus-write-buffer-as-coding-system
-              file gnus-cache-write-file-coding-system)
+              gnus-cache-write-file-coding-system file)
              (gnus-cache-change-buffer group)
              (set-buffer (cdr gnus-cache-buffer))
              (goto-char (point-max))
 
       ;; Read file.
       (with-temp-buffer
        (insert-file-contents-as-coding-system
-        file score-mode-coding-system)
+        score-mode-coding-system file)
        (goto-char (point-min))
        ;; Only do the loading if the score file isn't empty.
        (when (save-excursion (re-search-forward "[()0-9a-zA-Z]" nil t))
            ;; There are scores, so we write the file.
            (when (file-writable-p file)
              (gnus-write-buffer-as-coding-system
-              file score-mode-coding-system)
+              score-mode-coding-system file)
              (when gnus-score-after-write-file-function
                (funcall gnus-score-after-write-file-function file)))))
        (and gnus-score-uncacheable-files
 
       (condition-case nil
          (with-temp-buffer
            (insert-file-contents-as-coding-system
-            ding-file gnus-startup-file-coding-system)
+            gnus-startup-file-coding-system ding-file)
            (eval-region (point-min) (point-max)))
        (error
         (ding)
          (gnus-gnus-to-quick-newsrc-format)
          (gnus-run-hooks 'gnus-save-quick-newsrc-hook)
          (write-region-as-coding-system
-          (point-min) (point-max) (buffer-file-name)
-          gnus-startup-file-coding-system)
+          gnus-startup-file-coding-system
+          (point-min) (point-max) (buffer-file-name))
          (set-buffer-modified-p nil)
          (kill-buffer (current-buffer))
          (gnus-message
 
   ;; Write the buffer.
   (write-region-as-binary (point-min) (point-max) file nil 'quietly))
 
-(defun gnus-write-buffer-as-coding-system (file coding-system)
+(defun gnus-write-buffer-as-coding-system (coding-system file)
   "Write the current buffer's contents to FILE with code conversion."
   ;; Make sure the directory exists.
   (gnus-make-directory (file-name-directory file))
   ;; Write the buffer.
   (write-region-as-coding-system
-   (point-min) (point-max) file coding-system nil 'quietly))
+   coding-system (point-min) (point-max) file nil 'quietly))
 
 (defun gnus-delete-file (file)
   "Delete FILE if it exists."
 
         (after-insert-file-functions nil)
        (find-file-hooks nil))
     (insert-file-contents-as-coding-system
-     filename nnheader-file-coding-system visit beg end replace)))
+     nnheader-file-coding-system filename visit beg end replace)))
 
 (defun nnheader-find-file-noselect (&rest args)
   (let ((format-alist nil)
        (after-insert-file-functions nil)
        (find-file-hooks nil))
     (apply 'find-file-noselect-as-coding-system
-          (car args) nnheader-file-coding-system (cdr args))))
+          nnheader-file-coding-system args)))
 
 (defun nnheader-auto-mode-alist ()
   "Return an `auto-mode-alist' with only the .gz (etc) thingies."
 
        (let ((auto-mode-alist (nnheader-auto-mode-alist))
              (pathname-coding-system nnmail-file-coding-system))
          (insert-file-contents-as-coding-system
-          file nnmail-file-coding-system)
+          nnmail-file-coding-system file)
          t)
       (file-error nil))))
 
   "Do a `write-region', and then set the file modes."
   (let ((pathname-coding-system 'binary))
     (write-region-as-coding-system
-     start end filename nnmail-file-coding-system append visit lockname)
+     nnmail-file-coding-system start end filename append visit lockname)
     (set-file-modes filename nnmail-default-file-modes)))
 
 ;;;
 
   (unless (file-exists-p (file-name-directory (buffer-file-name)))
     (make-directory (file-name-directory (buffer-file-name)) t))
   (write-region-as-coding-system
-   (point-min) (point-max) (buffer-file-name) score-mode-coding-system)
+   score-mode-coding-system (point-min) (point-max) (buffer-file-name))
   (set-buffer-modified-p nil)
   (bury-buffer (current-buffer))
   (let ((buf (current-buffer)))