--- a/build-aux/texinfo.tex
+++ b/build-aux/texinfo.tex
@@ -3,7 +3,7 @@
 % Load plain if necessary, i.e., if running under initex.
 \expandafter\ifx\csname fmtname\endcsname\relax\input plain\fi
 %
-\def\texinfoversion{2011-01-15.17}
+\def\texinfoversion{2011-01-19.09}
 %
 % Copyright 1985, 1986, 1988, 1990, 1991, 1992, 1993, 1994, 1995,
 % 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006,
@@ -118,8 +118,8 @@
 \ifx\putwordChapter\undefined   \gdef\putwordChapter{Chapter}\fi
 \ifx\putwordfile\undefined      \gdef\putwordfile{file}\fi
 \ifx\putwordin\undefined        \gdef\putwordin{in}\fi
-\ifx\putwordIndexIsEmpty\undefined     \gdef\putwordIndexIsEmpty{(Index is empty)}\fi
-\ifx\putwordIndexNonexistent\undefined \gdef\putwordIndexNonexistent{(Index is nonexistent)}\fi
+\ifx\putwordIndexIsEmpty\undefined       \gdef\putwordIndexIsEmpty{(Index is empty)}\fi
+\ifx\putwordIndexNonexistent\undefined   \gdef\putwordIndexNonexistent{(Index is nonexistent)}\fi
 \ifx\putwordInfo\undefined      \gdef\putwordInfo{Info}\fi
 \ifx\putwordInstanceVariableof\undefined \gdef\putwordInstanceVariableof{Instance Variable of}\fi
 \ifx\putwordMethodon\undefined  \gdef\putwordMethodon{Method on}\fi
@@ -163,10 +163,12 @@
 \chardef\dashChar  = `\-
 \chardef\dotChar   = `\.
 \chardef\exclamChar= `\!
+\chardef\hashChar  = `\#
 \chardef\lquoteChar= `\`
 \chardef\questChar = `\?
 \chardef\rquoteChar= `\'
 \chardef\semiChar  = `\;
+\chardef\slashChar = `\/
 \chardef\underChar = `\_
 
 % Ignore a token.
@@ -557,7 +559,7 @@
 \parseargdef\end{%
   \if 1\csname iscond.#1\endcsname
   \else
-    % The general wording of \badenverr may not be ideal, but... --kasal, 06nov03
+    % The general wording of \badenverr may not be ideal.
     \expandafter\checkenv\csname#1\endcsname
     \csname E#1\endcsname
     \endgroup
@@ -2253,12 +2255,14 @@
 
 % Markup style setup for left and right quotes.
 \defmarkupstylesetup\markupsetuplq{%
-  \expandafter\let\expandafter \temp \csname markupsetuplq\currentmarkupstyle\endcsname
+  \expandafter\let\expandafter \temp
+    \csname markupsetuplq\currentmarkupstyle\endcsname
   \ifx\temp\relax \markupsetuplqdefault \else \temp \fi
 }
 
 \defmarkupstylesetup\markupsetuprq{%
-  \expandafter\let\expandafter \temp \csname markupsetuprq\currentmarkupstyle\endcsname
+  \expandafter\let\expandafter \temp
+    \csname markupsetuprq\currentmarkupstyle\endcsname
   \ifx\temp\relax \markupsetuprqdefault \else \temp \fi
 }
 
@@ -2487,6 +2491,22 @@
     \codex
   }
 }
+% Handle @url similarly to \code, but allows line breaks after .#?/ (only).
+{
+  \catcode`\.=\active \catcode`\#=\active
+  \catcode`\?=\active \catcode`\/=\active
+  %
+  \global\def\urefcode{\begingroup
+    \setupmarkupstyle{code}%
+    \catcode\dotChar=\active   \catcode\hashChar=\active
+    \catcode\questChar=\active \catcode\slashChar=\active
+    \let.\urefcodedot
+    \let#\urefcodehash
+    \let?\urefcodequestion
+    \let/\urefcodeslash
+    \codex
+  }
+}
 
 \def\realdash{-}
 \def\codedash{-\discretionary{}{}{}}
@@ -2501,6 +2521,24 @@
              \discretionary{}{}{}}%
             {\_}%
 }
+% we put a little stretch before and after the breakable chars, to help
+% line breaking of long url's.  The unequal skips make look better in
+% cmtt at least, especially for dots.
+\def\urefprestretch{\nobreak \hskip0pt plus.13em }
+\def\urefpoststretch{\allowbreak \hskip0pt plus.1em }
+\def\urefcodedot{\urefprestretch .\urefpoststretch}
+\def\urefcodehash{\urefprestretch \#\urefpoststretch}
+\def\urefcodequestion{\urefprestretch ?\urefpoststretch}
+\def\urefcodeslash{\futurelet\next\urefcodeslashfinish}
+{
+  \catcode`\/=\active
+  \global\def\urefcodeslashfinish{%
+    \urefprestretch \slashChar
+    % Allow line break only after the final / in a sequence of
+    % slashes, to avoid line break between the slashes in http://.
+    \ifx\next/\else \urefpoststretch \fi
+  }
+}
 \def\codex #1{\tclose{#1}\endgroup}
 
 % An additional complication: the above will allow breaks after, e.g.,
@@ -2589,10 +2627,13 @@
       \ifpdf
         \unhbox0             % PDF: 2nd arg given, show only it
       \else
-        \unhbox0\ (\code{#1})% DVI: 2nd arg given, show both it and url
+        % \empty at the end of \scantokens arg gets rid of
+        % trailing newline (and ultimate spurious whitespace).
+        \unhbox0\ (\urefcode{\scantokens{#1\empty}})% DVI: 2nd arg given,
+                                                    % show both it and url
       \fi
     \else
-      \code{#1}% only url given, so show it
+      \urefcode{\scantokens{#1\empty}}% only url given, so show it
     \fi
   \fi
   \endlink
@@ -3034,8 +3075,9 @@
 \newif\ifsetshortcontentsaftertitlepage
  \let\setshortcontentsaftertitlepage = \setshortcontentsaftertitlepagetrue
 
-\parseargdef\shorttitlepage{\begingroup\hbox{}\vskip 1.5in \chaprm \centerline{#1}%
-        \endgroup\page\hbox{}\page}
+\parseargdef\shorttitlepage{%
+  \begingroup \hbox{}\vskip 1.5in \chaprm \centerline{#1}%
+  \endgroup\page\hbox{}\page}
 
 \envdef\titlepage{%
   % Open one extra group, as we want to close it in the middle of \Etitlepage.
@@ -5243,7 +5285,8 @@
   \global\let\subsubsection = \appendixsubsubsec
 }
 
-\outer\parseargdef\unnumbered{\unnmhead0{#1}} % normally unnmhead0 calls unnumberedzzz
+% normally unnmhead0 calls unnumberedzzz:
+\outer\parseargdef\unnumbered{\unnmhead0{#1}}
 \def\unnumberedzzz#1{%
   \global\secno=0 \global\subsecno=0 \global\subsubsecno=0
     \global\advance\unnumberedno by 1
@@ -5287,40 +5330,47 @@
 \let\top\unnumbered
 
 % Sections.
+% 
 \outer\parseargdef\numberedsec{\numhead1{#1}} % normally calls seczzz
 \def\seczzz#1{%
   \global\subsecno=0 \global\subsubsecno=0  \global\advance\secno by 1
   \sectionheading{#1}{sec}{Ynumbered}{\the\chapno.\the\secno}%
 }
 
-\outer\parseargdef\appendixsection{\apphead1{#1}} % normally calls appendixsectionzzz
+% normally calls appendixsectionzzz:
+\outer\parseargdef\appendixsection{\apphead1{#1}}
 \def\appendixsectionzzz#1{%
   \global\subsecno=0 \global\subsubsecno=0  \global\advance\secno by 1
   \sectionheading{#1}{sec}{Yappendix}{\appendixletter.\the\secno}%
 }
 \let\appendixsec\appendixsection
 
-\outer\parseargdef\unnumberedsec{\unnmhead1{#1}} % normally calls unnumberedseczzz
+% normally calls unnumberedseczzz:
+\outer\parseargdef\unnumberedsec{\unnmhead1{#1}}
 \def\unnumberedseczzz#1{%
   \global\subsecno=0 \global\subsubsecno=0  \global\advance\secno by 1
   \sectionheading{#1}{sec}{Ynothing}{\the\unnumberedno.\the\secno}%
 }
 
 % Subsections.
-\outer\parseargdef\numberedsubsec{\numhead2{#1}} % normally calls numberedsubseczzz
+% 
+% normally calls numberedsubseczzz:
+\outer\parseargdef\numberedsubsec{\numhead2{#1}}
 \def\numberedsubseczzz#1{%
   \global\subsubsecno=0  \global\advance\subsecno by 1
   \sectionheading{#1}{subsec}{Ynumbered}{\the\chapno.\the\secno.\the\subsecno}%
 }
 
-\outer\parseargdef\appendixsubsec{\apphead2{#1}} % normally calls appendixsubseczzz
+% normally calls appendixsubseczzz:
+\outer\parseargdef\appendixsubsec{\apphead2{#1}}
 \def\appendixsubseczzz#1{%
   \global\subsubsecno=0  \global\advance\subsecno by 1
   \sectionheading{#1}{subsec}{Yappendix}%
                  {\appendixletter.\the\secno.\the\subsecno}%
 }
 
-\outer\parseargdef\unnumberedsubsec{\unnmhead2{#1}} %normally calls unnumberedsubseczzz
+% normally calls unnumberedsubseczzz:
+\outer\parseargdef\unnumberedsubsec{\unnmhead2{#1}}
 \def\unnumberedsubseczzz#1{%
   \global\subsubsecno=0  \global\advance\subsecno by 1
   \sectionheading{#1}{subsec}{Ynothing}%
@@ -5328,21 +5378,25 @@
 }
 
 % Subsubsections.
-\outer\parseargdef\numberedsubsubsec{\numhead3{#1}} % normally numberedsubsubseczzz
+% 
+% normally numberedsubsubseczzz:
+\outer\parseargdef\numberedsubsubsec{\numhead3{#1}}
 \def\numberedsubsubseczzz#1{%
   \global\advance\subsubsecno by 1
   \sectionheading{#1}{subsubsec}{Ynumbered}%
                  {\the\chapno.\the\secno.\the\subsecno.\the\subsubsecno}%
 }
 
-\outer\parseargdef\appendixsubsubsec{\apphead3{#1}} % normally appendixsubsubseczzz
+% normally appendixsubsubseczzz:
+\outer\parseargdef\appendixsubsubsec{\apphead3{#1}}
 \def\appendixsubsubseczzz#1{%
   \global\advance\subsubsecno by 1
   \sectionheading{#1}{subsubsec}{Yappendix}%
                  {\appendixletter.\the\secno.\the\subsecno.\the\subsubsecno}%
 }
 
-\outer\parseargdef\unnumberedsubsubsec{\unnmhead3{#1}} %normally unnumberedsubsubseczzz
+% normally unnumberedsubsubseczzz:
+\outer\parseargdef\unnumberedsubsubsec{\unnmhead3{#1}}
 \def\unnumberedsubsubseczzz#1{%
   \global\advance\subsubsecno by 1
   \sectionheading{#1}{subsubsec}{Ynothing}%
@@ -7237,7 +7291,8 @@
 
 % @inforef is relatively simple.
 \def\inforef #1{\inforefzzz #1,,,,**}
-\def\inforefzzz #1,#2,#3,#4**{\putwordSee{} \putwordInfo{} \putwordfile{} \file{\ignorespaces #3{}},
+\def\inforefzzz #1,#2,#3,#4**{%
+  \putwordSee{} \putwordInfo{} \putwordfile{} \file{\ignorespaces #3{}},
   node \samp{\ignorespaces#1{}}}
 
 % @node's only job in TeX is to define \lastnode, which is used in
@@ -7298,7 +7353,7 @@
       \toks0 = \expandafter{\lastsection}%
       \immediate \writexrdef{title}{\the\toks0 }%
       \immediate \writexrdef{snt}{\csname #2\endcsname}% \Ynumbered etc.
-      \safewhatsit{\writexrdef{pg}{\folio}}% will be written later, during \shipout
+      \safewhatsit{\writexrdef{pg}{\folio}}% will be written later, at \shipout
     }%
   \fi
 }