Wrap <filename> in \url{...} if justification is turned on. This

prevents the majority of the remaining margin overflows.  However,
this solution isn't very elegant in that it completely ignores
<replaceable>s inside of a <filename> element.  The normal TeX that
gets output inside of \url{..} confuses TeX, so we must simply process
the children of replaceable without doing any additional formatting
inside of the \url{..} (such as putting the text into italics).

More work needs to be done on this.

share/sgml/freebsd.dsl

@@ -1,4 +1,4 @@
-<!-- $FreeBSD: doc/share/sgml/freebsd.dsl,v 1.52 2001/09/08 01:59:22 murray Exp $ -->
+<!-- $FreeBSD: doc/share/sgml/freebsd.dsl,v 1.53 2001/09/08 02:21:19 murray Exp $ -->
 
 <!DOCTYPE style-sheet PUBLIC "-//James Clark//DTD DSSSL Style Sheet//EN" [
 <!ENTITY % output.html		"IGNORE">
@@ -214,6 +214,34 @@
 
         (define %hyphenation%
           #t)
+
+        ;; This could be done better.  However, I was not able to come
+        ;; up with a more elegant solution that still builds the entire
+        ;; Handbook.  If you can come up with a better way to do this,
+        ;; please do!
+
+        (element filename
+          (let ((%factor% (if %verbatim-size-factor% 
+			      %verbatim-size-factor% 
+			      1.0)))
+            (make sequence
+	      font-family-name: %mono-font-family%
+	      font-size: (* (inherited-font-size) %factor%)
+	      (make formatting-instruction data:
+		    "\\url{")
+	      (with-mode ignore-mode
+		(process-children))
+	      (make formatting-instruction data:
+		    "}"))))
+
+         ;; If we wrap something in \url{..} in the TeX mode, then we
+         ;; can't get too funky with putting other stuff inside of it
+         ;; or TeX will get confused.
+
+         (mode ignore-mode
+            (element replaceable
+               (process-children)))
+
       ]]>
 
       <!-- Print only ................................................... -->