Fallout from resurrecting doprnt.

 src/doc.c (get_doc_string): Improve the format passed to `error'.
 src/doprnt.c (doprnt): Improve commentary.
 src/term.c (init_tty) [MSDOS]: Fix 1st argument to maybe_fatal.
 src/Makefile.in (TAGS): Depend on $(M_FILE) and $(S_FILE), and scan
 them with etags.
 src/makefile.w32-in (TAGS): Depend on $(CURDIR)/m/intel386.h and
 $(CURDIR)/s/ms-w32.h.
 (TAGS-gmake): Scan $(CURDIR)/m/intel386.h and $(CURDIR)/s/ms-w32.h.

6 files changed, 52 insertions, 9 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index 537acb712b9..478a5aa2512 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,7 +1,19 @@
 2011-04-24  Eli Zaretskii  <eliz@gnu.org>
 
+        * doc.c (get_doc_string): Improve the format passed to `error'.
+
+        * doprnt.c (doprnt): Improve commentary.
+
+        * term.c (init_tty) [MSDOS]: Fix 1st argument to maybe_fatal.
+
+        * Makefile.in (TAGS): Depend on $(M_FILE) and $(S_FILE), and scan
+        them with etags.
+
         * makefile.w32-in (globals.h): Add a dummy recipe, to make any
         changes in globals.h immediately force recompilation.
+        (TAGS): Depend on $(CURDIR)/m/intel386.h and
+        $(CURDIR)/s/ms-w32.h.
+        (TAGS-gmake): Scan $(CURDIR)/m/intel386.h and $(CURDIR)/s/ms-w32.h.
 
         * character.c (Fchar_direction): Function deleted.
         (syms_of_character): Don't defsubr it.
diff --git a/src/Makefile.in b/src/Makefile.in
index e1195968f7f..8b596430cf5 100644
--- a/src/Makefile.in
+++ b/src/Makefile.in
@@ -748,10 +748,10 @@ extraclean: distclean
 ctagsfiles1 = [xyzXYZ]*.[hcm]
 ctagsfiles2 = [a-wA-W]*.[hcm]
 
-TAGS: $(srcdir)/$(ctagsfiles1) $(srcdir)/$(ctagsfiles2)
+TAGS: $(srcdir)/$(ctagsfiles1) $(srcdir)/$(ctagsfiles2) $(M_FILE) $(S_FILE)
         ../lib-src/etags --include=TAGS-LISP --include=$(lwlibdir)/TAGS \
           --regex='/[   ]*DEFVAR_[A-Z_  (]+"\([^"]+\)"/' \
-          $(srcdir)/$(ctagsfiles1) $(srcdir)/$(ctagsfiles2)
+          $(srcdir)/$(ctagsfiles1) $(srcdir)/$(ctagsfiles2) $(M_FILE) $(S_FILE)
 frc:
 TAGS-LISP: frc
         $(MAKE) -f $(lispdir)/Makefile TAGS-LISP ETAGS=../lib-src/etags
diff --git a/src/doc.c b/src/doc.c
index 354aff84979..4b75deaba5c 100644
--- a/src/doc.c
+++ b/src/doc.c
@@ -253,7 +253,9 @@ get_doc_string (Lisp_Object filepos, int unibyte, int definition)
           else if (c == '_')
             *to++ = 037;
           else
-            error ("Invalid data in documentation file -- ^A followed by code 0%o", c);
+            error ("\
+Invalid data in documentation file -- %c followed by code %03o",
+                   1, (unsigned)c);
         }
       else
         *to++ = *from++;
diff --git a/src/doprnt.c b/src/doprnt.c
index f182529b801..f124db13221 100644
--- a/src/doprnt.c
+++ b/src/doprnt.c
@@ -1,6 +1,6 @@
 /* Output like sprintf to a buffer of specified size.
-   Also takes args differently: pass one pointer to an array of strings
-   in addition to the format string which is separate.
+   Also takes args differently: pass one pointer to the end
+   of the format string in addition to the format string itself.
    Copyright (C) 1985, 2001-2011  Free Software Foundation, Inc.
 
 This file is part of GNU Emacs.
@@ -18,6 +18,35 @@ GNU General Public License for more details.
 You should have received a copy of the GNU General Public License
 along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
 
+/* If you think about replacing this with some similar standard C function of
+   the printf family (such as vsnprintf), please note that this function
+   supports the following Emacs-specific features:
+
+   . For %c conversions, it produces a string with the multibyte representation
+     of the (`int') argument, suitable for display in an Emacs buffer.
+
+   . For %s and %c, when field width is specified (e.g., %25s), it accounts for
+     the diplay width of each character, according to char-width-table.  That
+     is, it does not assume that each character takes one column on display.
+
+   . If the size of the buffer is not enough to produce the formatted string in
+     its entirety, it makes sure that truncation does not chop the last
+     character in the middle of its multibyte sequence, producing an invalid
+     sequence.
+
+   . It accepts a pointer to the end of the format string, so the format string
+     could include embedded null characters.
+
+   . It signals an error if the length of the formatted string is about to
+     overflow MOST_POSITIVE_FIXNUM, to avoid producing strings longer than what
+     Emacs can handle.
+
+   OTOH, this function supports only a small subset of the standard C formatted
+   output facilities.  E.g., %u and %ll are not supported, and precision is
+   largely ignored except for converting floating-point values.  However, this
+   is okay, as this function is supposed to be called from `error' and similar
+   functions, and thus does not need to support features beyond those in
+   `Fformat', which is used by `error' on the Lisp level.  */
 
 #include <config.h>
 #include <stdio.h>
diff --git a/src/makefile.w32-in b/src/makefile.w32-in
index eebc4006bc3..0dd06b7efc3 100644
--- a/src/makefile.w32-in
+++ b/src/makefile.w32-in
@@ -330,7 +330,7 @@ cleanall:	clean
 ##
 ## This works only with GNU Make.
 
-TAGS: $(OBJ0) $(OBJ1) $(OBJ2)
+TAGS: $(OBJ0) $(OBJ1) $(OBJ2) $(CURDIR)/m/intel386.h $(CURDIR)/s/ms-w32.h
         $(MAKE) $(MFLAGS) TAGS-$(MAKETYPE)
 
 TAGS-LISP: $(OBJ0) $(OBJ1) $(OBJ2)
@@ -344,7 +344,7 @@ TAGS-gmake:
           $(patsubst $(BLD)%.$(O),$(CURDIR)%.c,$(OBJ1))
         ../lib-src/$(BLD)/etags.exe -a --regex=@../nt/emacs-src.tags \
           $(patsubst $(BLD)%.$(O),$(CURDIR)%.c,$(OBJ2)) \
-          $(CURDIR)/*.h
+          $(CURDIR)/*.h $(CURDIR)/m/intel386.h $(CURDIR)/s/ms-w32.h
 
 TAGS-nmake:
         echo This target is not supported with NMake
diff --git a/src/term.c b/src/term.c
index cae83f4d269..28709138a17 100644
--- a/src/term.c
+++ b/src/term.c
@@ -3121,7 +3121,7 @@ init_tty (const char *name, const char *terminal_type, int must_succeed)
   terminal = create_terminal ();
 #ifdef MSDOS
   if (been_here > 0)
-    maybe_fatal (1, 0, "Attempt to create another terminal %s", "",
+    maybe_fatal (0, 0, "Attempt to create another terminal %s", "",
                  name, "");
   been_here = 1;
   tty = &the_only_display_info;
@@ -3627,7 +3627,7 @@ vfatal (const char *str, va_list ap)
 
 /* Auxiliary error-handling function for init_tty.
    Delete TERMINAL, then call error or fatal with str1 or str2,
-   respectively, according to MUST_SUCCEED.  */
+   respectively, according to whether MUST_SUCCEED is zero or not.  */
 
 static void
 maybe_fatal (int must_succeed, struct terminal *terminal,