Stop keeping multiple doc copies for items defined multiple times

It was always a nuisance to keep all the copies in sync.
* src/doc.c (Fsnarf_documentation): Don't skip entire files.
Instead, skip individual doc strings starting with "SKIP".
* doc/lispref/internals.texi (Writing Emacs Primitives):
Mention this skipping.
* lisp/term/ns-win.el, lisp/term/pc-win.el, src/dosfns.c:
* src/frame.c, src/nsfns.m, src/nsmenu.m, src/nsterm.m:
* src/w16select.c, src/w32fns.c, src/w32menu.c, src/w32select.c:
* src/w32term.c, src/xmenu.c: Remove duplicated doc strings.
* src/xfns.c: Merge in information from doc string duplicates.

16 files changed, 170 insertions, 683 deletions

diff --git a/doc/lispref/internals.texi b/doc/lispref/internals.texi
index 8bf9abfc614..76be7bf0ac6 100644
--- a/doc/lispref/internals.texi
+++ b/doc/lispref/internals.texi
@@ -758,6 +758,13 @@ names in the documentation string from the ones used in the C code.
 @samp{usage:} is required if the function has an unlimited number of
 arguments.
 
+Some primitives have multiple definitions, one per platform (e.g.,
+@code{x-create-frame}).  In such cases, rather than writing the
+same documentation string in each definition, only one definition has
+the actual documentation.  The others have placeholders beginning with
+@samp{SKIP}, which are ignored by the function that parses the
+@file{DOC} file.
+
 All the usual rules for documentation strings in Lisp code
 (@pxref{Documentation Tips}) apply to C code documentation strings
 too.
diff --git a/lisp/term/ns-win.el b/lisp/term/ns-win.el
index ca2cc725a66..7d89ec33a46 100644
--- a/lisp/term/ns-win.el
+++ b/lisp/term/ns-win.el
@@ -437,14 +437,7 @@ Lines are highlighted according to `ns-input-line'."
 ;;;; File handling.
 
 (defun x-file-dialog (prompt dir default_filename mustmatch only_dir_p)
-"Read file name, prompting with PROMPT in directory DIR.
-Use a file selection dialog.  Select DEFAULT-FILENAME in the dialog's file
-selection box, if specified.  If MUSTMATCH is non-nil, the returned file
-or directory must exist.
-
-This function is only defined on NS, MS Windows, and X Windows with the
-Motif or Gtk toolkits.  With the Motif toolkit, ONLY-DIR-P is ignored.
-Otherwise, if ONLY-DIR-P is non-nil, the user can only select directories."
+"SKIP: real doc in xfns.c."
   (ns-read-file-name prompt dir mustmatch default_filename only_dir_p))
 
 (defun ns-open-file-using-panel ()
diff --git a/lisp/term/pc-win.el b/lisp/term/pc-win.el
index 3ed21b8e436..9c1b471d484 100644
--- a/lisp/term/pc-win.el
+++ b/lisp/term/pc-win.el
@@ -158,159 +158,59 @@ created."
 ;; a useful function for returning 'nil regardless of argument.
 
 ;; Note: Any re-definition in this file of a function that is defined
-;; in C on other platforms, should either have no doc-string, or one
-;; that is identical to the C version, but with the arglist signature
-;; at the end.  Otherwise help-split-fundoc gets confused on other
-;; platforms.  (Bug#10783)
+;; in C on other platforms, should either have a doc-string that
+;; starts with "SKIP", or one that is identical to the C version,
+;; but with the arglist signature at the end.  Otherwise
+;; help-split-fundoc gets confused on other platforms.  (Bug#10783)
 
-;; From src/xfns.c
 (defun x-list-fonts (_pattern &optional _face _frame _maximum width)
-  "Return a list of the names of available fonts matching PATTERN.
-If optional arguments FACE and FRAME are specified, return only fonts
-the same size as FACE on FRAME.
-
-PATTERN should be a string containing a font name in the XLFD,
-Fontconfig, or GTK format.  A font name given in the XLFD format may
-contain wildcard characters:
-  the * character matches any substring, and
-  the ? character matches any single character.
-  PATTERN is case-insensitive.
-
-The return value is a list of strings, suitable as arguments to
-`set-face-font'.
-
-Fonts Emacs can't use may or may not be excluded
-even if they match PATTERN and FACE.
-The optional fourth argument MAXIMUM sets a limit on how many
-fonts to match.  The first MAXIMUM fonts are reported.
-The optional fifth argument WIDTH, if specified, is a number of columns
-occupied by a character of a font.  In that case, return only fonts
-the WIDTH times as wide as FACE on FRAME."
+  "SKIP: real doc in xfaces.c."
   (if (or (null width) (and (numberp width) (= width 1)))
       (list "ms-dos")
     (list "no-such-font")))
 (defun x-display-pixel-width (&optional frame)
-  "Return the width in pixels of DISPLAY.
-The optional argument DISPLAY specifies which display to ask about.
-DISPLAY should be either a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.
-
-On \"multi-monitor\" setups this refers to the pixel width for all
-physical monitors associated with DISPLAY.  To get information for
-each physical monitor, use `display-monitor-attributes-list'."
+  "SKIP: real doc in xfns.c."
   (frame-width frame))
 (defun x-display-pixel-height (&optional frame)
-  "Return the height in pixels of DISPLAY.
-The optional argument DISPLAY specifies which display to ask about.
-DISPLAY should be either a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.
-
-On \"multi-monitor\" setups this refers to the pixel height for all
-physical monitors associated with DISPLAY.  To get information for
-each physical monitor, use `display-monitor-attributes-list'."
+  "SKIP: real doc in xfns.c."
   (frame-height frame))
 (defun x-display-planes (&optional _frame)
-  "Return the number of bitplanes of DISPLAY.
-The optional argument DISPLAY specifies which display to ask about.
-DISPLAY should be either a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display."
+  "SKIP: real doc in xfns.c."
   4) ;bg switched to 16 colors as well
 (defun x-display-color-cells (&optional _frame)
-  "Return the number of color cells of DISPLAY.
-The optional argument DISPLAY specifies which display to ask about.
-DISPLAY should be either a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display."
+  "SKIP: real doc in xfns.c."
   16)
 (defun x-server-max-request-size (&optional _frame)
-  "Return the maximum request size of the server of DISPLAY.
-The optional argument DISPLAY specifies which display to ask about.
-DISPLAY should be either a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display."
+  "SKIP: real doc in xfns.c."
   1000000) ; ???
 (defun x-server-vendor (&optional _frame)
-  "Return the \"vendor ID\" string of the GUI software on TERMINAL.
-
-\(Labeling every distributor as a \"vendor\" embodies the false assumption
-that operating systems cannot be developed and distributed noncommercially.)
-
-For GNU and Unix systems, this queries the X server software; for
-MS-Windows, this queries the OS.
-
-The optional argument TERMINAL specifies which display to ask about.
-TERMINAL should be a terminal object, a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display."
+  "SKIP: real doc in xfns.c."
   "GNU")
 (defun x-server-version (&optional _frame)
-  "Return the version numbers of the GUI software on TERMINAL.
-The value is a list of three integers specifying the version of the GUI
-software in use.
-
-For GNU and Unix system, the first 2 numbers are the version of the X
-Protocol used on TERMINAL and the 3rd number is the distributor-specific
-release number.  For MS-Windows, the 3 numbers report the version and
-the build number of the OS.
-
-See also the function `x-server-vendor'.
-
-The optional argument TERMINAL specifies which display to ask about.
-TERMINAL should be a terminal object, a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display."
+  "SKIP: real doc in xfns.c."
   '(1 0 0))
 (defun x-display-screens (&optional _frame)
-  "Return the number of screens on the server of DISPLAY.
-The optional argument DISPLAY specifies which display to ask about.
-DISPLAY should be either a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display."
+  "SKIP: real doc in xfns.c."
   1)
 (defun x-display-mm-height (&optional _frame)
-  "Return the height in millimeters of DISPLAY.
-The optional argument DISPLAY specifies which display to ask about.
-DISPLAY should be either a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.
-
-On \"multi-monitor\" setups this refers to the height in millimeters for
-all physical monitors associated with DISPLAY.  To get information
-for each physical monitor, use `display-monitor-attributes-list'."
+  "SKIP: real doc in xfns.c."
   245) ; Guess the size of my...
 (defun x-display-mm-width (&optional _frame)
-  "Return the width in millimeters of DISPLAY.
-The optional argument DISPLAY specifies which display to ask about.
-DISPLAY should be either a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.
-
-On \"multi-monitor\" setups this refers to the width in millimeters for
-all physical monitors associated with TERMINAL.  To get information
-for each physical monitor, use `display-monitor-attributes-list'."
+  "SKIP: real doc in xfns.c."
   322)  ; ...monitor, EZ...
 (defun x-display-backing-store (&optional _frame)
-  "Return an indication of whether DISPLAY does backing store.
-The value may be `always', `when-mapped', or `not-useful'.
-The optional argument DISPLAY specifies which display to ask about.
-DISPLAY should be either a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display."
+  "SKIP: real doc in xfns.c."
   'not-useful)
 (defun x-display-visual-class (&optional _frame)
-  "Return the visual class of DISPLAY.
-The value is one of the symbols `static-gray', `gray-scale',
-`static-color', `pseudo-color', `true-color', or `direct-color'.
-
-The optional argument DISPLAY specifies which display to ask about.
-DISPLAY should be either a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display."
+  "SKIP: real doc in xfns.c."
   'static-color)
 (fset 'x-display-save-under 'ignore)
 (fset 'x-get-resource 'ignore)
 
-;; From lisp/term/x-win.el
 (defvar x-display-name "pc"
-  "The name of the window display on which Emacs was started.
-On X, the display name of individual X frames is recorded in the
-`display' frame parameter.")
+  "SKIP: real doc in common-win.el.")
 (defvar x-colors (mapcar 'car msdos-color-values)
-  "List of basic colors available on color displays.
-For X, the list comes from the `rgb.txt' file,v 10.41 94/02/20.
-For Nextstep, this is a list of non-PANTONE colors returned by
-the operating system.")
+  "SKIP: real doc in common-win.el.")
 
 ;; From lisp/term/w32-win.el
 ;
diff --git a/src/doc.c b/src/doc.c
index 3424bffdf9a..4264ed50640 100644
--- a/src/doc.c
+++ b/src/doc.c
@@ -535,7 +535,6 @@ the same file name is found in the `doc-directory'.  */)
   EMACS_INT pos;
   Lisp_Object sym;
   char *p, *name;
-  bool skip_file = 0;
   ptrdiff_t count;
   char const *dirname;
   ptrdiff_t dirlen;
@@ -609,34 +608,24 @@ the same file name is found in the `doc-directory'.  */)
         {
           end = strchr (p, '\n');
 
-          /* See if this is a file name, and if it is a file in build-files.  */
-          if (p[1] == 'S')
-            {
-              skip_file = 0;
-              if (end - p > 4 && end[-2] == '.'
-                  && (end[-1] == 'o' || end[-1] == 'c'))
-                {
-                  ptrdiff_t len = end - p - 2;
-                  char *fromfile = SAFE_ALLOCA (len + 1);
-                  memcpy (fromfile, &p[2], len);
-                  fromfile[len] = 0;
-                  if (fromfile[len-1] == 'c')
-                    fromfile[len-1] = 'o';
-
-                  skip_file = NILP (Fmember (build_string (fromfile),
-                                             Vbuild_files));
-                }
-            }
+          /* We used to skip files not in build_files, so that when a
+             function was defined several times in different files
+             (typically, once in xterm, once in w32term, ...), we only
+             paid attention to the relevant one.
+
+             But this meant the doc had to be kept and updated in
+             multiple files.  Nowadays we keep the doc only in eg xterm.
+             The (f)boundp checks below ensure we don't report
+             docs for eg w32-specific items on X.
+          */
 
           sym = oblookup (Vobarray, p + 2,
                           multibyte_chars_in_text ((unsigned char *) p + 2,
                                                    end - p - 2),
                           end - p - 2);
-          /* Check skip_file so that when a function is defined several
-             times in different files (typically, once in xterm, once in
-             w32term, ...), we only pay attention to the one that
-             matters.  */
-          if (! skip_file && SYMBOLP (sym))
+          /* Ignore docs that start with SKIP.  These mark
+             placeholders where the real doc is elsewhere.  */
+          if (SYMBOLP (sym))
             {
               /* Attach a docstring to a variable?  */
               if (p[1] == 'V')
@@ -644,8 +633,9 @@ the same file name is found in the `doc-directory'.  */)
                   /* Install file-position as variable-documentation property
                      and make it negative for a user-variable
                      (doc starts with a `*').  */
-                  if (!NILP (Fboundp (sym))
+                  if ((!NILP (Fboundp (sym))
                       || !NILP (Fmemq (sym, delayed_init)))
+                      && strncmp (end, "\nSKIP", 5))
                     Fput (sym, Qvariable_documentation,
                           make_number ((pos + end + 1 - buf)
                                        * (end[1] == '*' ? -1 : 1)));
@@ -654,7 +644,7 @@ the same file name is found in the `doc-directory'.  */)
               /* Attach a docstring to a function?  */
               else if (p[1] == 'F')
                 {
-                  if (!NILP (Ffboundp (sym)))
+                  if (!NILP (Ffboundp (sym)) && strncmp (end, "\nSKIP", 5))
                     store_function_docstring (sym, pos + end + 1 - buf);
                 }
               else if (p[1] == 'S')
diff --git a/src/dosfns.c b/src/dosfns.c
index c6d4d5b8d82..f9845a3049d 100644
--- a/src/dosfns.c
+++ b/src/dosfns.c
@@ -480,11 +480,7 @@ x_set_title (struct frame *f, Lisp_Object name)
 #endif /* !HAVE_X_WINDOWS */
 
 DEFUN ("file-system-info", Ffile_system_info, Sfile_system_info, 1, 1, 0,
-       doc: /* Return storage information about the file system FILENAME is on.
-Value is a list of floats (TOTAL FREE AVAIL), where TOTAL is the total
-storage of the file system, FREE is the free storage, and AVAIL is the
-storage available to a non-superuser.  All 3 numbers are in bytes.
-If the underlying system call fails, value is nil.  */)
+       doc: /* SKIP: real doc in fileio.c.  */)
   (Lisp_Object filename)
 {
   struct statfs stfs;
diff --git a/src/frame.c b/src/frame.c
index 9eac242ea3f..fdde3d99a93 100644
--- a/src/frame.c
+++ b/src/frame.c
@@ -317,7 +317,7 @@ predicates which report frame's specific UI-related capabilities.  */)
 /* Placeholder used by temacs -nw before window.el is loaded.  */
 DEFUN ("frame-windows-min-size", Fframe_windows_min_size,
        Sframe_windows_min_size, 4, 4, 0,
-       doc: /* */
+       doc: /* SKIP: real doc in window.el.  */
        attributes: const)
      (Lisp_Object frame, Lisp_Object horizontal,
       Lisp_Object ignore, Lisp_Object pixelwise)
diff --git a/src/nsfns.m b/src/nsfns.m
index 06827f6dd19..6407560d89e 100644
--- a/src/nsfns.m
+++ b/src/nsfns.m
@@ -998,15 +998,7 @@ get_geometry_from_preferences (struct ns_display_info *dpyinfo,
 
 DEFUN ("x-create-frame", Fx_create_frame, Sx_create_frame,
        1, 1, 0,
-       doc: /* Make a new Nextstep window, called a "frame" in Emacs terms.
-Return an Emacs frame object.
-PARMS is an alist of frame parameters.
-If the parameters specify that the frame should not have a minibuffer,
-and do not specify a specific minibuffer window to use,
-then `default-minibuffer-frame' must be a frame whose minibuffer can
-be shared by the new frame.
-
-This function is an internal primitive--use `make-frame' instead.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
      (Lisp_Object parms)
 {
   struct frame *f;
@@ -1702,7 +1694,7 @@ If VALUE is nil, the default is removed.  */)
 DEFUN ("x-server-max-request-size", Fx_server_max_request_size,
        Sx_server_max_request_size,
        0, 1, 0,
-       doc: /* This function is a no-op.  It is only present for completeness.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
      (Lisp_Object terminal)
 {
   check_ns_display_info (terminal);
@@ -1713,12 +1705,7 @@ DEFUN ("x-server-max-request-size", Fx_server_max_request_size,
 
 
 DEFUN ("x-server-vendor", Fx_server_vendor, Sx_server_vendor, 0, 1, 0,
-       doc: /* Return the "vendor ID" string of Nextstep display server TERMINAL.
-\(Labeling every distributor as a "vendor" embodies the false assumption
-that operating systems cannot be developed and distributed noncommercially.)
-The optional argument TERMINAL specifies which display to ask about.
-TERMINAL should be a terminal object, a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object terminal)
 {
   check_ns_display_info (terminal);
@@ -1731,14 +1718,7 @@ If omitted or nil, that stands for the selected frame's display.  */)
 
 
 DEFUN ("x-server-version", Fx_server_version, Sx_server_version, 0, 1, 0,
-       doc: /* Return the version numbers of the server of display TERMINAL.
-The value is a list of three integers: the major and minor
-version numbers of the X Protocol in use, and the distributor-specific release
-number.  See also the function `x-server-vendor'.
-
-The optional argument TERMINAL specifies which display to ask about.
-TERMINAL should be a terminal object, a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object terminal)
 {
   check_ns_display_info (terminal);
@@ -1753,14 +1733,7 @@ If omitted or nil, that stands for the selected frame's display.  */)
 
 
 DEFUN ("x-display-screens", Fx_display_screens, Sx_display_screens, 0, 1, 0,
-       doc: /* Return the number of screens on Nextstep display server TERMINAL.
-The optional argument TERMINAL specifies which display to ask about.
-TERMINAL should be a terminal object, a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.
-
-Note: "screen" here is not in Nextstep terminology but in X11's.  For
-the number of physical monitors, use `(length
-\(display-monitor-attributes-list TERMINAL))' instead.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object terminal)
 {
   check_ns_display_info (terminal);
@@ -1769,14 +1742,7 @@ the number of physical monitors, use `(length
 
 
 DEFUN ("x-display-mm-height", Fx_display_mm_height, Sx_display_mm_height, 0, 1, 0,
-       doc: /* Return the height in millimeters of the Nextstep display TERMINAL.
-The optional argument TERMINAL specifies which display to ask about.
-TERMINAL should be a terminal object, a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.
-
-On \"multi-monitor\" setups this refers to the height in millimeters for
-all physical monitors associated with TERMINAL.  To get information
-for each physical monitor, use `display-monitor-attributes-list'.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object terminal)
 {
   struct ns_display_info *dpyinfo = check_ns_display_info (terminal);
@@ -1786,14 +1752,7 @@ for each physical monitor, use `display-monitor-attributes-list'.  */)
 
 
 DEFUN ("x-display-mm-width", Fx_display_mm_width, Sx_display_mm_width, 0, 1, 0,
-       doc: /* Return the width in millimeters of the Nextstep display TERMINAL.
-The optional argument TERMINAL specifies which display to ask about.
-TERMINAL should be a terminal object, a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.
-
-On \"multi-monitor\" setups this refers to the width in millimeters for
-all physical monitors associated with TERMINAL.  To get information
-for each physical monitor, use `display-monitor-attributes-list'.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object terminal)
 {
   struct ns_display_info *dpyinfo = check_ns_display_info (terminal);
@@ -1804,14 +1763,11 @@ for each physical monitor, use `display-monitor-attributes-list'.  */)
 
 DEFUN ("x-display-backing-store", Fx_display_backing_store,
        Sx_display_backing_store, 0, 1, 0,
-       doc: /* Return an indication of whether the Nextstep display TERMINAL does backing store.
-The value may be `buffered', `retained', or `non-retained'.
-The optional argument TERMINAL specifies which display to ask about.
-TERMINAL should be a terminal object, a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object terminal)
 {
   check_ns_display_info (terminal);
+  /* Note that the xfns.c version has different return values.  */
   switch ([ns_get_window (terminal) backingType])
     {
     case NSBackingStoreBuffered:
@@ -1831,13 +1787,7 @@ If omitted or nil, that stands for the selected frame's display.  */)
 
 DEFUN ("x-display-visual-class", Fx_display_visual_class,
        Sx_display_visual_class, 0, 1, 0,
-       doc: /* Return the visual class of the Nextstep display TERMINAL.
-The value is one of the symbols `static-gray', `gray-scale',
-`static-color', `pseudo-color', `true-color', or `direct-color'.
-
-The optional argument TERMINAL specifies which display to ask about.
-TERMINAL should a terminal object, a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object terminal)
 {
   NSWindowDepth depth;
@@ -1863,10 +1813,7 @@ If omitted or nil, that stands for the selected frame's display.  */)
 
 DEFUN ("x-display-save-under", Fx_display_save_under,
        Sx_display_save_under, 0, 1, 0,
-       doc: /* Return t if TERMINAL supports the save-under feature.
-The optional argument TERMINAL specifies which display to ask about.
-TERMINAL should be a terminal object, a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object terminal)
 {
   check_ns_display_info (terminal);
@@ -1890,12 +1837,7 @@ If omitted or nil, that stands for the selected frame's display.  */)
 
 DEFUN ("x-open-connection", Fx_open_connection, Sx_open_connection,
        1, 3, 0,
-       doc: /* Open a connection to a display server.
-DISPLAY is the name of the display to connect to.
-Optional second arg XRM-STRING is a string of resources in xrdb format.
-If the optional third arg MUST-SUCCEED is non-nil,
-terminate Emacs if we can't open the connection.
-\(In the Nextstep version, the last two arguments are currently ignored.)  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
      (Lisp_Object display, Lisp_Object resource_string, Lisp_Object must_succeed)
 {
   struct ns_display_info *dpyinfo;
@@ -1920,10 +1862,7 @@ terminate Emacs if we can't open the connection.
 
 DEFUN ("x-close-connection", Fx_close_connection, Sx_close_connection,
        1, 1, 0,
-       doc: /* Close the connection to TERMINAL's Nextstep display server.
-For TERMINAL, specify a terminal object, a frame or a display name (a
-string).  If TERMINAL is nil, that stands for the selected frame's
-terminal.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
      (Lisp_Object terminal)
 {
   check_ns_display_info (terminal);
@@ -1933,7 +1872,7 @@ terminal.  */)
 
 
 DEFUN ("x-display-list", Fx_display_list, Sx_display_list, 0, 0, 0,
-       doc: /* Return the list of display names that Emacs has connections to.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
      (void)
 {
   Lisp_Object result = Qnil;
@@ -2306,8 +2245,7 @@ x_get_focus_frame (struct frame *frame)
 
 
 DEFUN ("xw-color-defined-p", Fxw_color_defined_p, Sxw_color_defined_p, 1, 2, 0,
-       doc: /* Internal function called by `color-defined-p', which see.
-\(Note that the Nextstep version of this function ignores FRAME.)  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
      (Lisp_Object color, Lisp_Object frame)
 {
   NSColor * col;
@@ -2317,7 +2255,7 @@ DEFUN ("xw-color-defined-p", Fxw_color_defined_p, Sxw_color_defined_p, 1, 2, 0,
 
 
 DEFUN ("xw-color-values", Fxw_color_values, Sxw_color_values, 1, 2, 0,
-       doc: /* Internal function called by `color-values', which see.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
      (Lisp_Object color, Lisp_Object frame)
 {
   NSColor * col;
@@ -2342,7 +2280,7 @@ DEFUN ("xw-color-values", Fxw_color_values, Sxw_color_values, 1, 2, 0,
 
 
 DEFUN ("xw-display-color-p", Fxw_display_color_p, Sxw_display_color_p, 0, 1, 0,
-       doc: /* Internal function called by `display-color-p', which see.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
      (Lisp_Object terminal)
 {
   NSWindowDepth depth;
@@ -2360,11 +2298,7 @@ DEFUN ("xw-display-color-p", Fxw_display_color_p, Sxw_display_color_p, 0, 1, 0,
 
 DEFUN ("x-display-grayscale-p", Fx_display_grayscale_p, Sx_display_grayscale_p,
        0, 1, 0,
-       doc: /* Return t if the Nextstep display supports shades of gray.
-Note that color displays do support shades of gray.
-The optional argument TERMINAL specifies which display to ask about.
-TERMINAL should be a terminal object, a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object terminal)
 {
   NSWindowDepth depth;
@@ -2378,14 +2312,7 @@ If omitted or nil, that stands for the selected frame's display.  */)
 
 DEFUN ("x-display-pixel-width", Fx_display_pixel_width, Sx_display_pixel_width,
        0, 1, 0,
-       doc: /* Return the width in pixels of the Nextstep display TERMINAL.
-The optional argument TERMINAL specifies which display to ask about.
-TERMINAL should be a terminal object, a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.
-
-On \"multi-monitor\" setups this refers to the pixel width for all
-physical monitors associated with TERMINAL.  To get information for
-each physical monitor, use `display-monitor-attributes-list'.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object terminal)
 {
   struct ns_display_info *dpyinfo = check_ns_display_info (terminal);
@@ -2396,14 +2323,7 @@ each physical monitor, use `display-monitor-attributes-list'.  */)
 
 DEFUN ("x-display-pixel-height", Fx_display_pixel_height,
        Sx_display_pixel_height, 0, 1, 0,
-       doc: /* Return the height in pixels of the Nextstep display TERMINAL.
-The optional argument TERMINAL specifies which display to ask about.
-TERMINAL should be a terminal object, a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.
-
-On \"multi-monitor\" setups this refers to the pixel height for all
-physical monitors associated with TERMINAL.  To get information for
-each physical monitor, use `display-monitor-attributes-list'.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object terminal)
 {
   struct ns_display_info *dpyinfo = check_ns_display_info (terminal);
@@ -2648,10 +2568,7 @@ Internal use only, use `display-monitor-attributes-list' instead.  */)
 
 DEFUN ("x-display-planes", Fx_display_planes, Sx_display_planes,
        0, 1, 0,
-       doc: /* Return the number of bitplanes of the Nextstep display TERMINAL.
-The optional argument TERMINAL specifies which display to ask about.
-TERMINAL should be a terminal object, a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object terminal)
 {
   check_ns_display_info (terminal);
@@ -2662,10 +2579,7 @@ If omitted or nil, that stands for the selected frame's display.  */)
 
 DEFUN ("x-display-color-cells", Fx_display_color_cells, Sx_display_color_cells,
        0, 1, 0,
-       doc: /* Returns the number of color cells of the Nextstep display TERMINAL.
-The optional argument TERMINAL specifies which display to ask about.
-TERMINAL should be a terminal object, a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object terminal)
 {
   struct ns_display_info *dpyinfo = check_ns_display_info (terminal);
@@ -2753,35 +2667,7 @@ compute_tip_xy (struct frame *f,
 
 
 DEFUN ("x-show-tip", Fx_show_tip, Sx_show_tip, 1, 6, 0,
-       doc: /* Show STRING in a \"tooltip\" window on frame FRAME.
-A tooltip window is a small window displaying a string.
-
-This is an internal function; Lisp code should call `tooltip-show'.
-
-FRAME nil or omitted means use the selected frame.
-
-PARMS is an optional list of frame parameters which can be used to
-change the tooltip's appearance.
-
-Automatically hide the tooltip after TIMEOUT seconds.  TIMEOUT nil
-means use the default timeout of 5 seconds.
-
-If the list of frame parameters PARMS contains a `left' parameter,
-display the tooltip at that x-position.  If the list of frame parameters
-PARMS contains no `left' but a `right' parameter, display the tooltip
-right-adjusted at that x-position. Otherwise display it at the
-x-position of the mouse, with offset DX added (default is 5 if DX isn't
-specified).
-
-Likewise for the y-position: If a `top' frame parameter is specified, it
-determines the position of the upper edge of the tooltip window.  If a
-`bottom' parameter but no `top' frame parameter is specified, it
-determines the position of the lower edge of the tooltip window.
-Otherwise display the tooltip window at the y-position of the mouse,
-with offset DY added (default is -10).
-
-A tooltip's maximum size is specified by `x-max-tooltip-size'.
-Text larger than the specified size is clipped.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
      (Lisp_Object string, Lisp_Object frame, Lisp_Object parms, Lisp_Object timeout, Lisp_Object dx, Lisp_Object dy)
 {
   int root_x, root_y;
@@ -2842,8 +2728,7 @@ Text larger than the specified size is clipped.  */)
 
 
 DEFUN ("x-hide-tip", Fx_hide_tip, Sx_hide_tip, 0, 0, 0,
-       doc: /* Hide the current tooltip window, if there is any.
-Value is t if tooltip was open, nil otherwise.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
      (void)
 {
   if (ns_tooltip == nil || ![ns_tooltip isActive])
diff --git a/src/nsmenu.m b/src/nsmenu.m
index 58b45fb38e5..29b0f99e642 100644
--- a/src/nsmenu.m
+++ b/src/nsmenu.m
@@ -1874,7 +1874,7 @@ DEFUN ("ns-reset-menu", Fns_reset_menu, Sns_reset_menu, 0, 0, 0,
 
 
 DEFUN ("menu-or-popup-active-p", Fmenu_or_popup_active_p, Smenu_or_popup_active_p, 0, 0, 0,
-       doc: /* Return t if a menu or popup dialog is active.  */)
+       doc: /* SKIP: real doc in xmenu.c. */)
      (void)
 {
   return popup_activated () ? Qt : Qnil;
diff --git a/src/nsterm.m b/src/nsterm.m
index 8a66643cfb7..627a61cac62 100644
--- a/src/nsterm.m
+++ b/src/nsterm.m
@@ -9380,27 +9380,17 @@ This variable is ignored on macOS < 10.7 and GNUstep.  Default is t.  */);
 
   /* TODO: move to common code */
   DEFVAR_LISP ("x-toolkit-scroll-bars", Vx_toolkit_scroll_bars,
-               doc: /* Which toolkit scroll bars Emacs uses, if any.
-A value of nil means Emacs doesn't use toolkit scroll bars.
-With the X Window system, the value is a symbol describing the
-X toolkit.  Possible values are: gtk, motif, xaw, or xaw3d.
-With MS Windows or Nextstep, the value is t.  */);
+               doc: /* SKIP: real doc in xterm.c.  */);
   Vx_toolkit_scroll_bars = Qt;
 
   DEFVAR_BOOL ("x-use-underline-position-properties",
                x_use_underline_position_properties,
-     doc: /*Non-nil means make use of UNDERLINE_POSITION font properties.
-A value of nil means ignore them.  If you encounter fonts with bogus
-UNDERLINE_POSITION font properties, for example 7x13 on XFree prior
-to 4.1, set this to nil. */);
+     doc: /* SKIP: real doc in xterm.c.  */);
   x_use_underline_position_properties = 0;
 
   DEFVAR_BOOL ("x-underline-at-descent-line",
                x_underline_at_descent_line,
-     doc: /* Non-nil means to draw the underline at the same place as the descent line.
-A value of nil means to draw the underline according to the value of the
-variable `x-use-underline-position-properties', which is usually at the
-baseline level.  The default value is nil.  */);
+     doc: /* SKIP: real doc in xterm.c.  */);
   x_underline_at_descent_line = 0;
 
   /* Tell Emacs about this window system.  */
diff --git a/src/w16select.c b/src/w16select.c
index ed3d041f2df..2d740a3ee61 100644
--- a/src/w16select.c
+++ b/src/w16select.c
@@ -678,43 +678,11 @@ syms_of_win16select (void)
   defsubr (&Sw16_selection_exists_p);
 
   DEFVAR_LISP ("selection-coding-system", Vselection_coding_system,
-               doc: /* Coding system for communicating with other programs.
-
-For MS-Windows and MS-DOS:
-When sending or receiving text via selection and clipboard, the text
-is encoded or decoded by this coding system.  The default value is
-the current system default encoding on 9x/Me, `utf-16le-dos'
-\(Unicode) on NT/W2K/XP, and `iso-latin-1-dos' on MS-DOS.
-
-For X Windows:
-When sending text via selection and clipboard, if the target
-data-type matches with the type of this coding system, it is used
-for encoding the text.  Otherwise (including the case that this
-variable is nil), a proper coding system is used as below:
-
-data-type       coding system
----------       -------------
-UTF8_STRING     utf-8
-COMPOUND_TEXT   compound-text-with-extensions
-STRING          iso-latin-1
-C_STRING        no-conversion
-
-When receiving text, if this coding system is non-nil, it is used
-for decoding regardless of the data-type.  If this is nil, a
-proper coding system is used according to the data-type as above.
-
-See also the documentation of the variable `x-select-request-type' how
-to control which data-type to request for receiving text.
-
-The default value is nil.  */);
+               doc: /* SKIP: real doc in select.el.  */);
   Vselection_coding_system = intern ("iso-latin-1-dos");
 
   DEFVAR_LISP ("next-selection-coding-system", Vnext_selection_coding_system,
-               doc: /* Coding system for the next communication with other programs.
-Usually, `selection-coding-system' is used for communicating with
-other programs (X Windows clients or MS Windows programs).  But, if this
-variable is set, it is used for the next communication only.
-After the communication, this variable is set to nil.  */);
+               doc: /* SKIP: real doc in select.el.  */);
   Vnext_selection_coding_system = Qnil;
 
   DEFSYM (QCLIPBOARD, "CLIPBOARD");
diff --git a/src/w32fns.c b/src/w32fns.c
index 2b8c34a5ab5..2b920f29c65 100644
--- a/src/w32fns.c
+++ b/src/w32fns.c
@@ -5670,15 +5670,7 @@ x_default_font_parameter (struct frame *f, Lisp_Object parms)
 
 DEFUN ("x-create-frame", Fx_create_frame, Sx_create_frame,
        1, 1, 0,
-       doc: /* Make a new window, which is called a \"frame\" in Emacs terms.
-Return an Emacs frame object.
-PARAMETERS is an alist of frame parameters.
-If the parameters specify that the frame should not have a minibuffer,
-and do not specify a specific minibuffer window to use,
-then `default-minibuffer-frame' must be a frame whose minibuffer can
-be shared by the new frame.
-
-This function is an internal primitive--use `make-frame' instead.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object parameters)
 {
   struct frame *f;
@@ -6097,8 +6089,7 @@ x_get_focus_frame (struct frame *frame)
 }
 
 DEFUN ("xw-color-defined-p", Fxw_color_defined_p, Sxw_color_defined_p, 1, 2, 0,
-       doc: /* Internal function called by `color-defined-p', which see.
-\(Note that the Nextstep version of this function ignores FRAME.)  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object color, Lisp_Object frame)
 {
   XColor foo;
@@ -6113,7 +6104,7 @@ DEFUN ("xw-color-defined-p", Fxw_color_defined_p, Sxw_color_defined_p, 1, 2, 0,
 }
 
 DEFUN ("xw-color-values", Fxw_color_values, Sxw_color_values, 1, 2, 0,
-       doc: /* Internal function called by `color-values', which see.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object color, Lisp_Object frame)
 {
   XColor foo;
@@ -6130,7 +6121,7 @@ DEFUN ("xw-color-values", Fxw_color_values, Sxw_color_values, 1, 2, 0,
 }
 
 DEFUN ("xw-display-color-p", Fxw_display_color_p, Sxw_display_color_p, 0, 1, 0,
-       doc: /* Internal function called by `display-color-p', which see.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object display)
 {
   struct w32_display_info *dpyinfo = check_x_display_info (display);
@@ -6143,11 +6134,7 @@ DEFUN ("xw-display-color-p", Fxw_display_color_p, Sxw_display_color_p, 0, 1, 0,
 
 DEFUN ("x-display-grayscale-p", Fx_display_grayscale_p,
        Sx_display_grayscale_p, 0, 1, 0,
-       doc: /* Return t if DISPLAY supports shades of gray.
-Note that color displays do support shades of gray.
-The optional argument DISPLAY specifies which display to ask about.
-DISPLAY should be either a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object display)
 {
   struct w32_display_info *dpyinfo = check_x_display_info (display);
@@ -6160,14 +6147,7 @@ If omitted or nil, that stands for the selected frame's display.  */)
 
 DEFUN ("x-display-pixel-width", Fx_display_pixel_width,
        Sx_display_pixel_width, 0, 1, 0,
-       doc: /* Return the width in pixels of DISPLAY.
-The optional argument DISPLAY specifies which display to ask about.
-DISPLAY should be either a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.
-
-On \"multi-monitor\" setups this refers to the pixel width for all
-physical monitors associated with DISPLAY.  To get information for
-each physical monitor, use `display-monitor-attributes-list'.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object display)
 {
   struct w32_display_info *dpyinfo = check_x_display_info (display);
@@ -6177,14 +6157,7 @@ each physical monitor, use `display-monitor-attributes-list'.  */)
 
 DEFUN ("x-display-pixel-height", Fx_display_pixel_height,
        Sx_display_pixel_height, 0, 1, 0,
-       doc: /* Return the height in pixels of DISPLAY.
-The optional argument DISPLAY specifies which display to ask about.
-DISPLAY should be either a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.
-
-On \"multi-monitor\" setups this refers to the pixel height for all
-physical monitors associated with DISPLAY.  To get information for
-each physical monitor, use `display-monitor-attributes-list'.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object display)
 {
   struct w32_display_info *dpyinfo = check_x_display_info (display);
@@ -6194,10 +6167,7 @@ each physical monitor, use `display-monitor-attributes-list'.  */)
 
 DEFUN ("x-display-planes", Fx_display_planes, Sx_display_planes,
        0, 1, 0,
-       doc: /* Return the number of bitplanes of DISPLAY.
-The optional argument DISPLAY specifies which display to ask about.
-DISPLAY should be either a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object display)
 {
   struct w32_display_info *dpyinfo = check_x_display_info (display);
@@ -6207,10 +6177,7 @@ If omitted or nil, that stands for the selected frame's display.  */)
 
 DEFUN ("x-display-color-cells", Fx_display_color_cells, Sx_display_color_cells,
        0, 1, 0,
-       doc: /* Return the number of color cells of DISPLAY.
-The optional argument DISPLAY specifies which display to ask about.
-DISPLAY should be either a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object display)
 {
   struct w32_display_info *dpyinfo = check_x_display_info (display);
@@ -6228,57 +6195,28 @@ If omitted or nil, that stands for the selected frame's display.  */)
 DEFUN ("x-server-max-request-size", Fx_server_max_request_size,
        Sx_server_max_request_size,
        0, 1, 0,
-       doc: /* Return the maximum request size of the server of DISPLAY.
-The optional argument DISPLAY specifies which display to ask about.
-DISPLAY should be either a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object display)
 {
   return make_number (1);
 }
 
 DEFUN ("x-server-vendor", Fx_server_vendor, Sx_server_vendor, 0, 1, 0,
-       doc: /* Return the "vendor ID" string of the GUI software on TERMINAL.
-
-\(Labeling every distributor as a "vendor" embodies the false assumption
-that operating systems cannot be developed and distributed noncommercially.)
-
-For GNU and Unix systems, this queries the X server software; for
-MS-Windows, this queries the OS.
-
-The optional argument TERMINAL specifies which display to ask about.
-TERMINAL should be a terminal object, a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object terminal)
 {
   return build_string ("Microsoft Corp.");
 }
 
 DEFUN ("x-server-version", Fx_server_version, Sx_server_version, 0, 1, 0,
-       doc: /* Return the version numbers of the GUI software on TERMINAL.
-The value is a list of three integers specifying the version of the GUI
-software in use.
-
-For GNU and Unix system, the first 2 numbers are the version of the X
-Protocol used on TERMINAL and the 3rd number is the distributor-specific
-release number.  For MS-Windows, the 3 numbers report the version and
-the build number of the OS.
-
-See also the function `x-server-vendor'.
-
-The optional argument TERMINAL specifies which display to ask about.
-TERMINAL should be a terminal object, a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object terminal)
 {
   return list3i (w32_major_version, w32_minor_version, w32_build_number);
 }
 
 DEFUN ("x-display-screens", Fx_display_screens, Sx_display_screens, 0, 1, 0,
-       doc: /* Return the number of screens on the server of DISPLAY.
-The optional argument DISPLAY specifies which display to ask about.
-DISPLAY should be either a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object display)
 {
   return make_number (1);
@@ -6286,14 +6224,7 @@ If omitted or nil, that stands for the selected frame's display.  */)
 
 DEFUN ("x-display-mm-height", Fx_display_mm_height,
        Sx_display_mm_height, 0, 1, 0,
-       doc: /* Return the height in millimeters of DISPLAY.
-The optional argument DISPLAY specifies which display to ask about.
-DISPLAY should be either a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.
-
-On \"multi-monitor\" setups this refers to the height in millimeters for
-all physical monitors associated with DISPLAY.  To get information
-for each physical monitor, use `display-monitor-attributes-list'.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object display)
 {
   struct w32_display_info *dpyinfo = check_x_display_info (display);
@@ -6309,14 +6240,7 @@ for each physical monitor, use `display-monitor-attributes-list'.  */)
 }
 
 DEFUN ("x-display-mm-width", Fx_display_mm_width, Sx_display_mm_width, 0, 1, 0,
-       doc: /* Return the width in millimeters of DISPLAY.
-The optional argument DISPLAY specifies which display to ask about.
-DISPLAY should be either a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.
-
-On \"multi-monitor\" setups this refers to the width in millimeters for
-all physical monitors associated with TERMINAL.  To get information
-for each physical monitor, use `display-monitor-attributes-list'.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object display)
 {
   struct w32_display_info *dpyinfo = check_x_display_info (display);
@@ -6333,11 +6257,7 @@ for each physical monitor, use `display-monitor-attributes-list'.  */)
 
 DEFUN ("x-display-backing-store", Fx_display_backing_store,
        Sx_display_backing_store, 0, 1, 0,
-       doc: /* Return an indication of whether DISPLAY does backing store.
-The value may be `always', `when-mapped', or `not-useful'.
-The optional argument DISPLAY specifies which display to ask about.
-DISPLAY should be either a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object display)
 {
   return intern ("not-useful");
@@ -6345,13 +6265,7 @@ If omitted or nil, that stands for the selected frame's display.  */)
 
 DEFUN ("x-display-visual-class", Fx_display_visual_class,
        Sx_display_visual_class, 0, 1, 0,
-       doc: /* Return the visual class of DISPLAY.
-The value is one of the symbols `static-gray', `gray-scale',
-`static-color', `pseudo-color', `true-color', or `direct-color'.
-
-The optional argument DISPLAY specifies which display to ask about.
-DISPLAY should be either a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object display)
 {
   struct w32_display_info *dpyinfo = check_x_display_info (display);
@@ -6360,7 +6274,7 @@ If omitted or nil, that stands for the selected frame's display.  */)
   if (dpyinfo->has_palette)
       result = intern ("pseudo-color");
   else if (dpyinfo->n_planes * dpyinfo->n_cbits == 1)
-      result = intern ("static-grey");
+      result = intern ("static-gray");
   else if (dpyinfo->n_planes * dpyinfo->n_cbits == 4)
       result = intern ("static-color");
   else if (dpyinfo->n_planes * dpyinfo->n_cbits > 8)
@@ -6371,10 +6285,7 @@ If omitted or nil, that stands for the selected frame's display.  */)
 
 DEFUN ("x-display-save-under", Fx_display_save_under,
        Sx_display_save_under, 0, 1, 0,
-       doc: /* Return t if DISPLAY supports the save-under feature.
-The optional argument DISPLAY specifies which display to ask about.
-DISPLAY should be either a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object display)
 {
   return Qnil;
@@ -6639,12 +6550,7 @@ x_display_info_for_name (Lisp_Object name)
 }
 
 DEFUN ("x-open-connection", Fx_open_connection, Sx_open_connection,
-       1, 3, 0, doc: /* Open a connection to a display server.
-DISPLAY is the name of the display to connect to.
-Optional second arg XRM-STRING is a string of resources in xrdb format.
-If the optional third arg MUST-SUCCEED is non-nil,
-terminate Emacs if we can't open the connection.
-\(In the Nextstep version, the last two arguments are currently ignored.)  */)
+       1, 3, 0, doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object display, Lisp_Object xrm_string, Lisp_Object must_succeed)
 {
   char *xrm_option;
@@ -6726,9 +6632,7 @@ terminate Emacs if we can't open the connection.
 
 DEFUN ("x-close-connection", Fx_close_connection,
        Sx_close_connection, 1, 1, 0,
-       doc: /* Close the connection to DISPLAY's server.
-For DISPLAY, specify either a frame or a display name (a string).
-If DISPLAY is nil, that stands for the selected frame's display.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object display)
 {
   struct w32_display_info *dpyinfo = check_x_display_info (display);
@@ -6746,7 +6650,7 @@ If DISPLAY is nil, that stands for the selected frame's display.  */)
 }
 
 DEFUN ("x-display-list", Fx_display_list, Sx_display_list, 0, 0, 0,
-       doc: /* Return the list of display names that Emacs has connections to.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (void)
 {
   Lisp_Object result = Qnil;
@@ -6759,17 +6663,7 @@ DEFUN ("x-display-list", Fx_display_list, Sx_display_list, 0, 0, 0,
 }
 
 DEFUN ("x-synchronize", Fx_synchronize, Sx_synchronize, 1, 2, 0,
-       doc: /* If ON is non-nil, report X errors as soon as the erring request is made.
-This function only has an effect on X Windows.  With MS Windows, it is
-defined but does nothing.
-
-If ON is nil, allow buffering of requests.
-Turning on synchronization prohibits the Xlib routines from buffering
-requests and seriously degrades performance, but makes debugging much
-easier.
-The optional second argument TERMINAL specifies which display to act on.
-TERMINAL should be a terminal object, a frame or a display name (a string).
-If TERMINAL is omitted or nil, that stands for the selected frame's display.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object on, Lisp_Object display)
 {
   return Qnil;
@@ -6785,21 +6679,7 @@ If TERMINAL is omitted or nil, that stands for the selected frame's display.  */
 
 DEFUN ("x-change-window-property", Fx_change_window_property,
        Sx_change_window_property, 2, 6, 0,
-       doc: /* Change window property PROP to VALUE on the X window of FRAME.
-PROP must be a string.  VALUE may be a string or a list of conses,
-numbers and/or strings.  If an element in the list is a string, it is
-converted to an atom and the value of the Atom is used.  If an element
-is a cons, it is converted to a 32 bit number where the car is the 16
-top bits and the cdr is the lower 16 bits.
-
-FRAME nil or omitted means use the selected frame.
-If TYPE is given and non-nil, it is the name of the type of VALUE.
-If TYPE is not given or nil, the type is STRING.
-FORMAT gives the size in bits of each element if VALUE is a list.
-It must be one of 8, 16 or 32.
-If VALUE is a string or FORMAT is nil or not given, FORMAT defaults to 8.
-If OUTER-P is non-nil, the property is changed for the outer X window of
-FRAME.  Default is to change on the edit X window.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object prop, Lisp_Object value, Lisp_Object frame,
    Lisp_Object type, Lisp_Object format, Lisp_Object outer_p)
 {
@@ -6825,8 +6705,7 @@ FRAME.  Default is to change on the edit X window.  */)
 
 DEFUN ("x-delete-window-property", Fx_delete_window_property,
        Sx_delete_window_property, 1, 2, 0,
-       doc: /* Remove window property PROP from X window of FRAME.
-FRAME nil or omitted means use the selected frame.  Value is PROP.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object prop, Lisp_Object frame)
 {
   struct frame *f = decode_window_system_frame (frame);
@@ -6847,21 +6726,7 @@ FRAME nil or omitted means use the selected frame.  Value is PROP.  */)
 
 DEFUN ("x-window-property", Fx_window_property, Sx_window_property,
        1, 6, 0,
-       doc: /* Value is the value of window property PROP on FRAME.
-If FRAME is nil or omitted, use the selected frame.
-
-On X Windows, the following optional arguments are also accepted:
-If TYPE is nil or omitted, get the property as a string.
-Otherwise TYPE is the name of the atom that denotes the type expected.
-If SOURCE is non-nil, get the property on that window instead of from
-FRAME.  The number 0 denotes the root window.
-If DELETE-P is non-nil, delete the property after retrieving it.
-If VECTOR-RET-P is non-nil, don't return a string but a vector of values.
-
-On MS Windows, this function accepts but ignores those optional arguments.
-
-Value is nil if FRAME hasn't a property with name PROP or if PROP has
-no value of TYPE (always string in the MS Windows case).  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object prop, Lisp_Object frame, Lisp_Object type,
    Lisp_Object source, Lisp_Object delete_p, Lisp_Object vector_ret_p)
 {
@@ -7326,35 +7191,7 @@ x_hide_tip (bool delete)
 
 
 DEFUN ("x-show-tip", Fx_show_tip, Sx_show_tip, 1, 6, 0,
-       doc: /* Show STRING in a \"tooltip\" window on frame FRAME.
-A tooltip window is a small window displaying a string.
-
-This is an internal function; Lisp code should call `tooltip-show'.
-
-FRAME nil or omitted means use the selected frame.
-
-PARMS is an optional list of frame parameters which can be
-used to change the tooltip's appearance.
-
-Automatically hide the tooltip after TIMEOUT seconds.  TIMEOUT nil
-means use the default timeout of 5 seconds.
-
-If the list of frame parameters PARMS contains a `left' parameter,
-display the tooltip at that x-position.  If the list of frame parameters
-PARMS contains no `left' but a `right' parameter, display the tooltip
-right-adjusted at that x-position. Otherwise display it at the
-x-position of the mouse, with offset DX added (default is 5 if DX isn't
-specified).
-
-Likewise for the y-position: If a `top' frame parameter is specified, it
-determines the position of the upper edge of the tooltip window.  If a
-`bottom' parameter but no `top' frame parameter is specified, it
-determines the position of the lower edge of the tooltip window.
-Otherwise display the tooltip window at the y-position of the mouse,
-with offset DY added (default is -10).
-
-A tooltip's maximum size is specified by `x-max-tooltip-size'.
-Text larger than the specified size is clipped.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object string, Lisp_Object frame, Lisp_Object parms,
    Lisp_Object timeout, Lisp_Object dx, Lisp_Object dy)
 {
@@ -7633,8 +7470,7 @@ Text larger than the specified size is clipped.  */)
 
 
 DEFUN ("x-hide-tip", Fx_hide_tip, Sx_hide_tip, 0, 0, 0,
-       doc: /* Hide the current tooltip window, if there is any.
-Value is t if tooltip was open, nil otherwise.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (void)
 {
   return x_hide_tip (!tooltip_reuse_hidden_frame);
@@ -7765,18 +7601,7 @@ w32_dialog_in_progress (Lisp_Object in_progress)
 }
 
 DEFUN ("x-file-dialog", Fx_file_dialog, Sx_file_dialog, 2, 5, 0,
-       doc: /* Read file name, prompting with PROMPT in directory DIR.
-Use a file selection dialog.  Select DEFAULT-FILENAME in the dialog's file
-selection box, if specified.  If MUSTMATCH is non-nil, the returned file
-or directory must exist.
-
-This function is only defined on NS, MS Windows, and X Windows with the
-Motif or Gtk toolkits.  With the Motif toolkit, ONLY-DIR-P is ignored.
-Otherwise, if ONLY-DIR-P is non-nil, the user can only select directories.
-On Windows 7 and later, the file selection dialog "remembers" the last
-directory where the user selected a file, and will open that directory
-instead of DIR on subsequent invocations of this function with the same
-value of DIR as in previous invocations; this is standard Windows behavior.  */)
+       doc: /* SKIP: real doc in xfns.c.  */)
   (Lisp_Object prompt, Lisp_Object dir, Lisp_Object default_filename, Lisp_Object mustmatch, Lisp_Object only_dir_p)
 {
   /* Filter index: 1: All Files, 2: Directories only  */
@@ -9242,11 +9067,7 @@ typedef BOOL (WINAPI *GetDiskFreeSpaceExA_Proc)
   (LPCSTR, PULARGE_INTEGER, PULARGE_INTEGER, PULARGE_INTEGER);
 
 DEFUN ("file-system-info", Ffile_system_info, Sfile_system_info, 1, 1, 0,
-       doc: /* Return storage information about the file system FILENAME is on.
-Value is a list of floats (TOTAL FREE AVAIL), where TOTAL is the total
-storage of the file system, FREE is the free storage, and AVAIL is the
-storage available to a non-superuser.  All 3 numbers are in bytes.
-If the underlying system call fails, value is nil.  */)
+       doc: /* SKIP: Real doc in fileio.c.  */)
   (Lisp_Object filename)
 {
   Lisp_Object encoded, value;
@@ -10529,9 +10350,7 @@ bass-down, bass-boost, bass-up, treble-down, treble-up  */);
 
 #if 0 /* TODO: Mouse cursor customization.  */
   DEFVAR_LISP ("x-pointer-shape", Vx_pointer_shape,
-               doc: /* The shape of the pointer when over text.
-Changing the value does not affect existing frames
-unless you set the mouse color.  */);
+               doc: /* SKIP: real doc in xfns.c.  */);
   Vx_pointer_shape = Qnil;
 
   Vx_nontext_pointer_shape = Qnil;
@@ -10539,58 +10358,42 @@ unless you set the mouse color.  */);
   Vx_mode_pointer_shape = Qnil;
 
   DEFVAR_LISP ("x-hourglass-pointer-shape", Vx_hourglass_pointer_shape,
-               doc: /* The shape of the pointer when Emacs is busy.
-This variable takes effect when you create a new frame
-or when you set the mouse color.  */);
+               doc: /* SKIP: real doc in xfns.c.  */);
   Vx_hourglass_pointer_shape = Qnil;
 
   DEFVAR_LISP ("x-sensitive-text-pointer-shape",
                Vx_sensitive_text_pointer_shape,
-               doc: /* The shape of the pointer when over mouse-sensitive text.
-This variable takes effect when you create a new frame
-or when you set the mouse color.  */);
+               doc: /* SKIP: real doc in xfns.c.  */);
   Vx_sensitive_text_pointer_shape = Qnil;
 
   DEFVAR_LISP ("x-window-horizontal-drag-cursor",
                Vx_window_horizontal_drag_shape,
-               doc: /* Pointer shape to use for indicating a window can be dragged horizontally.
-This variable takes effect when you create a new frame
-or when you set the mouse color.  */);
+               doc: /* SKIP: real doc in xfns.c.  */);
   Vx_window_horizontal_drag_shape = Qnil;
 
   DEFVAR_LISP ("x-window-vertical-drag-cursor",
                Vx_window_vertical_drag_shape,
-               doc: /* Pointer shape to use for indicating a window can be dragged vertically.
-This variable takes effect when you create a new frame
-or when you set the mouse color.  */);
+               doc: /* SKIP: real doc in xfns.c.  */);
   Vx_window_vertical_drag_shape = Qnil;
 #endif
 
   DEFVAR_LISP ("x-cursor-fore-pixel", Vx_cursor_fore_pixel,
-               doc: /* A string indicating the foreground color of the cursor box.  */);
+               doc: /* SKIP: real doc in xfns.c.  */);
   Vx_cursor_fore_pixel = Qnil;
 
   DEFVAR_LISP ("x-max-tooltip-size", Vx_max_tooltip_size,
-               doc: /* Maximum size for tooltips.
-Value is a pair (COLUMNS . ROWS).  Text larger than this is clipped.  */);
+               doc: /* SKIP: real doc in xfns.c.  */);
   Vx_max_tooltip_size = Fcons (make_number (80), make_number (40));
 
   DEFVAR_LISP ("x-no-window-manager", Vx_no_window_manager,
-               doc: /* Non-nil if no window manager is in use.
-Emacs doesn't try to figure this out; this is always nil
-unless you set it to something else.  */);
+               doc: /* SKIP: real doc in xfns.c.  */);
   /* We don't have any way to find this out, so set it to nil
      and maybe the user would like to set it to t.  */
   Vx_no_window_manager = Qnil;
 
   DEFVAR_LISP ("x-pixel-size-width-font-regexp",
                Vx_pixel_size_width_font_regexp,
-               doc: /* Regexp matching a font name whose width is the same as `PIXEL_SIZE'.
-
-Since Emacs gets width of a font matching with this regexp from
-PIXEL_SIZE field of the name, font finding mechanism gets faster for
-such a font.  This is especially effective for such large fonts as
-Chinese, Japanese, and Korean.  */);
+               doc: /* SKIP: real doc in xfns.c.  */);
   Vx_pixel_size_width_font_regexp = Qnil;
 
   DEFVAR_LISP ("w32-bdf-filename-alist",
diff --git a/src/w32menu.c b/src/w32menu.c
index 0cd7284c9b0..30ad54db26d 100644
--- a/src/w32menu.c
+++ b/src/w32menu.c
@@ -1571,7 +1571,7 @@ w32_free_menu_strings (HWND hwnd)
 /* The following is used by delayed window autoselection.  */
 
 DEFUN ("menu-or-popup-active-p", Fmenu_or_popup_active_p, Smenu_or_popup_active_p, 0, 0, 0,
-       doc: /* Return t if a menu or popup dialog is active on selected frame.  */)
+       doc: /* SKIP: real doc in xmenu.c.  */)
   (void)
 {
   struct frame *f;
diff --git a/src/w32select.c b/src/w32select.c
index c451b7ff933..ce062ccfe61 100644
--- a/src/w32select.c
+++ b/src/w32select.c
@@ -1170,45 +1170,13 @@ syms_of_w32select (void)
   defsubr (&Sw32_selection_targets);
 
   DEFVAR_LISP ("selection-coding-system", Vselection_coding_system,
-               doc: /* Coding system for communicating with other programs.
-
-For MS-Windows and MS-DOS:
-When sending or receiving text via selection and clipboard, the text
-is encoded or decoded by this coding system.  The default value is
-the current system default encoding on 9x/Me, `utf-16le-dos'
-\(Unicode) on NT/W2K/XP, and `iso-latin-1-dos' on MS-DOS.
-
-For X Windows:
-When sending text via selection and clipboard, if the target
-data-type matches with the type of this coding system, it is used
-for encoding the text.  Otherwise (including the case that this
-variable is nil), a proper coding system is used as below:
-
-data-type       coding system
----------       -------------
-UTF8_STRING     utf-8
-COMPOUND_TEXT   compound-text-with-extensions
-STRING          iso-latin-1
-C_STRING        no-conversion
-
-When receiving text, if this coding system is non-nil, it is used
-for decoding regardless of the data-type.  If this is nil, a
-proper coding system is used according to the data-type as above.
-
-See also the documentation of the variable `x-select-request-type' how
-to control which data-type to request for receiving text.
-
-The default value is nil.  */);
+               doc: /* SKIP: real doc in select.el.  */);
   /* The actual value is set dynamically in the dumped Emacs, see
      below. */
   Vselection_coding_system = Qnil;
 
   DEFVAR_LISP ("next-selection-coding-system", Vnext_selection_coding_system,
-               doc: /* Coding system for the next communication with other programs.
-Usually, `selection-coding-system' is used for communicating with
-other programs (X Windows clients or MS Windows programs).  But, if this
-variable is set, it is used for the next communication only.
-After the communication, this variable is set to nil.  */);
+               doc: /* SKIP: real doc in select.el.  */);
   Vnext_selection_coding_system = Qnil;
 
   DEFSYM (QCLIPBOARD, "CLIPBOARD");
diff --git a/src/w32term.c b/src/w32term.c
index c1d039c1375..97afb678c1d 100644
--- a/src/w32term.c
+++ b/src/w32term.c
@@ -7329,14 +7329,7 @@ syms_of_w32term (void)
   DEFSYM (Qrenamed_to, "renamed-to");
 
   DEFVAR_LISP ("x-wait-for-event-timeout", Vx_wait_for_event_timeout,
-    doc: /* How long to wait for X events.
-
-Emacs will wait up to this many seconds to receive X events after
-making changes which affect the state of the graphical interface.
-Under some window managers this can take an indefinite amount of time,
-so it is important to limit the wait.
-
-If set to a non-float value, there will be no wait at all.  */);
+    doc: /* SKIP: real doc in xterm.c.  */);
   Vx_wait_for_event_timeout = make_float (0.1);
 
   DEFVAR_INT ("w32-num-mouse-buttons",
@@ -7390,28 +7383,16 @@ the cursor have no effect.  */);
      from cus-start.el and other places, like "M-x set-variable".  */
   DEFVAR_BOOL ("x-use-underline-position-properties",
                x_use_underline_position_properties,
-     doc: /* Non-nil means make use of UNDERLINE_POSITION font properties.
-A value of nil means ignore them.  If you encounter fonts with bogus
-UNDERLINE_POSITION font properties, for example 7x13 on XFree prior
-to 4.1, set this to nil.  You can also use `underline-minimum-offset'
-to override the font's UNDERLINE_POSITION for small font display
-sizes.  */);
+     doc: /* SKIP: real doc in xterm.c.  */);
   x_use_underline_position_properties = 0;
 
   DEFVAR_BOOL ("x-underline-at-descent-line",
                x_underline_at_descent_line,
-     doc: /* Non-nil means to draw the underline at the same place as the descent line.
-A value of nil means to draw the underline according to the value of the
-variable `x-use-underline-position-properties', which is usually at the
-baseline level.  The default value is nil.  */);
+     doc: /* SKIP: real doc in xterm.c.  */);
   x_underline_at_descent_line = 0;
 
   DEFVAR_LISP ("x-toolkit-scroll-bars", Vx_toolkit_scroll_bars,
-               doc: /* Which toolkit scroll bars Emacs uses, if any.
-A value of nil means Emacs doesn't use toolkit scroll bars.
-With the X Window system, the value is a symbol describing the
-X toolkit.  Possible values are: gtk, motif, xaw, or xaw3d.
-With MS Windows or Nextstep, the value is t.  */);
+               doc: /* SKIP: real doc in xterm.c.  */);
   Vx_toolkit_scroll_bars = Qt;
 
   DEFVAR_BOOL ("w32-unicode-filenames",
diff --git a/src/xfns.c b/src/xfns.c
index 9f0d9468c14..78151c81380 100644
--- a/src/xfns.c
+++ b/src/xfns.c
@@ -4125,7 +4125,7 @@ x_focus_frame (struct frame *f, bool noactivate)
 
 
 DEFUN ("xw-color-defined-p", Fxw_color_defined_p, Sxw_color_defined_p, 1, 2, 0,
-       doc: /* Internal function called by `color-defined-p', which see.
+       doc: /* Internal function called by `color-defined-p'.
 \(Note that the Nextstep version of this function ignores FRAME.)  */)
   (Lisp_Object color, Lisp_Object frame)
 {
@@ -4141,7 +4141,8 @@ DEFUN ("xw-color-defined-p", Fxw_color_defined_p, Sxw_color_defined_p, 1, 2, 0,
 }
 
 DEFUN ("xw-color-values", Fxw_color_values, Sxw_color_values, 1, 2, 0,
-       doc: /* Internal function called by `color-values', which see.  */)
+       doc: /* Internal function called by `color-values'.
+\(Note that the Nextstep version of this function ignores FRAME.)  */)
   (Lisp_Object color, Lisp_Object frame)
 {
   XColor foo;
@@ -4156,7 +4157,7 @@ DEFUN ("xw-color-values", Fxw_color_values, Sxw_color_values, 1, 2, 0,
 }
 
 DEFUN ("xw-display-color-p", Fxw_display_color_p, Sxw_display_color_p, 0, 1, 0,
-       doc: /* Internal function called by `display-color-p', which see.  */)
+       doc: /* Internal function called by `display-color-p'.  */)
   (Lisp_Object terminal)
 {
   struct x_display_info *dpyinfo = check_x_display_info (terminal);
@@ -4212,6 +4213,7 @@ DEFUN ("x-display-pixel-width", Fx_display_pixel_width, Sx_display_pixel_width,
 The optional argument TERMINAL specifies which display to ask about.
 TERMINAL should be a terminal object, a frame or a display name (a string).
 If omitted or nil, that stands for the selected frame's display.
+\(On MS Windows, this function does not accept terminal objects.)
 
 On \"multi-monitor\" setups this refers to the pixel width for all
 physical monitors associated with TERMINAL.  To get information for
@@ -4229,6 +4231,7 @@ DEFUN ("x-display-pixel-height", Fx_display_pixel_height,
 The optional argument TERMINAL specifies which display to ask about.
 TERMINAL should be a terminal object, a frame or a display name (a string).
 If omitted or nil, that stands for the selected frame's display.
+\(On MS Windows, this function does not accept terminal objects.)
 
 On \"multi-monitor\" setups this refers to the pixel height for all
 physical monitors associated with TERMINAL.  To get information for
@@ -4245,7 +4248,8 @@ DEFUN ("x-display-planes", Fx_display_planes, Sx_display_planes,
        doc: /* Return the number of bitplanes of the X display TERMINAL.
 The optional argument TERMINAL specifies which display to ask about.
 TERMINAL should be a terminal object, a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.  */)
+If omitted or nil, that stands for the selected frame's display.
+\(On MS Windows, this function does not accept terminal objects.)  */)
   (Lisp_Object terminal)
 {
   struct x_display_info *dpyinfo = check_x_display_info (terminal);
@@ -4258,7 +4262,8 @@ DEFUN ("x-display-color-cells", Fx_display_color_cells, Sx_display_color_cells,
        doc: /* Return the number of color cells of the X display TERMINAL.
 The optional argument TERMINAL specifies which display to ask about.
 TERMINAL should be a terminal object, a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.  */)
+If omitted or nil, that stands for the selected frame's display.
+\(On MS Windows, this function does not accept terminal objects.)  */)
   (Lisp_Object terminal)
 {
   struct x_display_info *dpyinfo = check_x_display_info (terminal);
@@ -4282,7 +4287,10 @@ DEFUN ("x-server-max-request-size", Fx_server_max_request_size,
        doc: /* Return the maximum request size of the X server of display TERMINAL.
 The optional argument TERMINAL specifies which display to ask about.
 TERMINAL should be a terminal object, a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.  */)
+If omitted or nil, that stands for the selected frame's display.
+
+On MS Windows, this function just returns 1.
+On Nextstep, this function just returns nil.  */)
   (Lisp_Object terminal)
 {
   struct x_display_info *dpyinfo = check_x_display_info (terminal);
@@ -4297,8 +4305,8 @@ DEFUN ("x-server-vendor", Fx_server_vendor, Sx_server_vendor, 0, 1, 0,
 that operating systems cannot be developed and distributed noncommercially.)
 The optional argument TERMINAL specifies which display to ask about.
 
-For GNU and Unix systems, this queries the X server software; for
-MS-Windows, this queries the OS.
+For GNU and Unix systems, this queries the X server software.
+For MS Windows and Nextstep the result is hard-coded.
 
 TERMINAL should be a terminal object, a frame or a display name (a string).
 If omitted or nil, that stands for the selected frame's display.  */)
@@ -4318,8 +4326,9 @@ software in use.
 
 For GNU and Unix system, the first 2 numbers are the version of the X
 Protocol used on TERMINAL and the 3rd number is the distributor-specific
-release number.  For MS-Windows, the 3 numbers report the version and
-the build number of the OS.
+release number.  For MS Windows, the 3 numbers report the OS major and
+minor version and build number.  For Nextstep, the first 2 numbers are
+hard-coded and the 3rd represents the OS version.
 
 See also the function `x-server-vendor'.
 
@@ -4339,7 +4348,12 @@ DEFUN ("x-display-screens", Fx_display_screens, Sx_display_screens, 0, 1, 0,
        doc: /* Return the number of screens on the X server of display TERMINAL.
 The optional argument TERMINAL specifies which display to ask about.
 TERMINAL should be a terminal object, a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.  */)
+If omitted or nil, that stands for the selected frame's display.
+
+On MS Windows, this function just returns 1.
+On Nextstep, "screen" is in X terminology, not that of Nextstep.
+For the number of physical monitors, use `(length
+\(display-monitor-attributes-list TERMINAL))' instead.  */)
   (Lisp_Object terminal)
 {
   struct x_display_info *dpyinfo = check_x_display_info (terminal);
@@ -4352,6 +4366,7 @@ DEFUN ("x-display-mm-height", Fx_display_mm_height, Sx_display_mm_height, 0, 1,
 The optional argument TERMINAL specifies which display to ask about.
 TERMINAL should be a terminal object, a frame or a display name (a string).
 If omitted or nil, that stands for the selected frame's display.
+\(On MS Windows, this function does not accept terminal objects.)
 
 On \"multi-monitor\" setups this refers to the height in millimeters for
 all physical monitors associated with TERMINAL.  To get information
@@ -4368,6 +4383,7 @@ DEFUN ("x-display-mm-width", Fx_display_mm_width, Sx_display_mm_width, 0, 1, 0,
 The optional argument TERMINAL specifies which display to ask about.
 TERMINAL should be a terminal object, a frame or a display name (a string).
 If omitted or nil, that stands for the selected frame's display.
+\(On MS Windows, this function does not accept terminal objects.)
 
 On \"multi-monitor\" setups this refers to the width in millimeters for
 all physical monitors associated with TERMINAL.  To get information
@@ -4382,10 +4398,13 @@ for each physical monitor, use `display-monitor-attributes-list'.  */)
 DEFUN ("x-display-backing-store", Fx_display_backing_store,
        Sx_display_backing_store, 0, 1, 0,
        doc: /* Return an indication of whether X display TERMINAL does backing store.
-The value may be `always', `when-mapped', or `not-useful'.
 The optional argument TERMINAL specifies which display to ask about.
 TERMINAL should be a terminal object, a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.  */)
+If omitted or nil, that stands for the selected frame's display.
+
+The value may be `always', `when-mapped', or `not-useful'.
+On Nextstep, the value may be `buffered', `retained', or `non-retained'.
+On MS Windows, this returns nothing useful.  */)
   (Lisp_Object terminal)
 {
   struct x_display_info *dpyinfo = check_x_display_info (terminal);
@@ -4417,10 +4436,12 @@ DEFUN ("x-display-visual-class", Fx_display_visual_class,
        doc: /* Return the visual class of the X display TERMINAL.
 The value is one of the symbols `static-gray', `gray-scale',
 `static-color', `pseudo-color', `true-color', or `direct-color'.
+\(On MS Windows, the second and last result above are not possible.)
 
 The optional argument TERMINAL specifies which display to ask about.
 TERMINAL should a terminal object, a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.  */)
+If omitted or nil, that stands for the selected frame's display.
+\(On MS Windows, this function does not accept terminal objects.)  */)
   (Lisp_Object terminal)
 {
   struct x_display_info *dpyinfo = check_x_display_info (terminal);
@@ -4458,7 +4479,9 @@ DEFUN ("x-display-save-under", Fx_display_save_under,
        doc: /* Return t if the X display TERMINAL supports the save-under feature.
 The optional argument TERMINAL specifies which display to ask about.
 TERMINAL should be a terminal object, a frame or a display name (a string).
-If omitted or nil, that stands for the selected frame's display.  */)
+If omitted or nil, that stands for the selected frame's display.
+
+On MS Windows, this just returns nil.  */)
   (Lisp_Object terminal)
 {
   struct x_display_info *dpyinfo = check_x_display_info (terminal);
@@ -5652,8 +5675,8 @@ DEFUN ("x-close-connection", Fx_close_connection,
        Sx_close_connection, 1, 1, 0,
        doc: /* Close the connection to TERMINAL's X server.
 For TERMINAL, specify a terminal object, a frame or a display name (a
-string).  If TERMINAL is nil, that stands for the selected frame's
-terminal.  */)
+string).  If TERMINAL is nil, that stands for the selected frame's terminal.
+\(On MS Windows, this function does not accept terminal objects.)  */)
   (Lisp_Object terminal)
 {
   struct x_display_info *dpyinfo = check_x_display_info (terminal);
@@ -5926,8 +5949,6 @@ FRAME.  The number 0 denotes the root window.
 If DELETE-P is non-nil, delete the property after retrieving it.
 If VECTOR-RET-P is non-nil, don't return a string but a vector of values.
 
-On MS Windows, this function accepts but ignores those optional arguments.
-
 Value is nil if FRAME hasn't a property with name PROP or if PROP has
 no value of TYPE (always string in the MS Windows case).  */)
   (Lisp_Object prop, Lisp_Object frame, Lisp_Object type,
@@ -7039,18 +7060,7 @@ clean_up_file_dialog (void *arg)
 
 
 DEFUN ("x-file-dialog", Fx_file_dialog, Sx_file_dialog, 2, 5, 0,
-       doc: /* Read file name, prompting with PROMPT in directory DIR.
-Use a file selection dialog.  Select DEFAULT-FILENAME in the dialog's file
-selection box, if specified.  If MUSTMATCH is non-nil, the returned file
-or directory must exist.
-
-This function is only defined on NS, MS Windows, and X Windows with the
-Motif or Gtk toolkits.  With the Motif toolkit, ONLY-DIR-P is ignored.
-Otherwise, if ONLY-DIR-P is non-nil, the user can only select directories.
-On Windows 7 and later, the file selection dialog "remembers" the last
-directory where the user selected a file, and will open that directory
-instead of DIR on subsequent invocations of this function with the same
-value of DIR as in previous invocations; this is standard Windows behavior.  */)
+       doc: /* SKIP: real doc in USE_GTK definition in xfns.c.  */)
   (Lisp_Object prompt, Lisp_Object dir, Lisp_Object default_filename,
    Lisp_Object mustmatch, Lisp_Object only_dir_p)
 {
@@ -7219,10 +7229,10 @@ or directory must exist.
 This function is only defined on NS, MS Windows, and X Windows with the
 Motif or Gtk toolkits.  With the Motif toolkit, ONLY-DIR-P is ignored.
 Otherwise, if ONLY-DIR-P is non-nil, the user can only select directories.
-On Windows 7 and later, the file selection dialog "remembers" the last
+On MS Windows 7 and later, the file selection dialog "remembers" the last
 directory where the user selected a file, and will open that directory
 instead of DIR on subsequent invocations of this function with the same
-value of DIR as in previous invocations; this is standard Windows behavior.  */)
+value of DIR as in previous invocations; this is standard MS Windows behavior.  */)
   (Lisp_Object prompt, Lisp_Object dir, Lisp_Object default_filename, Lisp_Object mustmatch, Lisp_Object only_dir_p)
 {
   struct frame *f = SELECTED_FRAME ();
@@ -7797,9 +7807,9 @@ unless you set it to something else.  */);
                Vx_pixel_size_width_font_regexp,
     doc: /* Regexp matching a font name whose width is the same as `PIXEL_SIZE'.
 
-Since Emacs gets width of a font matching with this regexp from
-PIXEL_SIZE field of the name, font finding mechanism gets faster for
-such a font.  This is especially effective for such large fonts as
+Since Emacs gets the width of a font matching this regexp from the
+PIXEL_SIZE field of the name, the font-finding mechanism gets faster for
+such a font.  This is especially effective for large fonts such as
 Chinese, Japanese, and Korean.  */);
   Vx_pixel_size_width_font_regexp = Qnil;
 
diff --git a/src/xmenu.c b/src/xmenu.c
index e7ef31ac564..835db9191f1 100644
--- a/src/xmenu.c
+++ b/src/xmenu.c
@@ -278,12 +278,7 @@ popup_get_selection (XEvent *initial_event, struct x_display_info *dpyinfo,
 }
 
 DEFUN ("x-menu-bar-open-internal", Fx_menu_bar_open_internal, Sx_menu_bar_open_internal, 0, 1, "i",
-       doc: /* Start key navigation of the menu bar in FRAME.
-This initially opens the first menu bar item and you can then navigate with the
-arrow keys, select a menu entry with the return key or cancel with the
-escape key.  If FRAME has no menu bar this function does nothing.
-
-If FRAME is nil or not given, use the selected frame.  */)
+       doc: /* SKIP: real doc in USE_GTK definition in xmenu.c.  */)
   (Lisp_Object frame)
 {
   XEvent ev;
@@ -2376,7 +2371,8 @@ popup_activated (void)
 /* The following is used by delayed window autoselection.  */
 
 DEFUN ("menu-or-popup-active-p", Fmenu_or_popup_active_p, Smenu_or_popup_active_p, 0, 0, 0,
-       doc: /* Return t if a menu or popup dialog is active.  */)
+       doc: /* Return t if a menu or popup dialog is active.
+\(On MS Windows, this refers to the selected frame.)  */)
   (void)
 {
   return (popup_activated ()) ? Qt : Qnil;