more material

diff --git a/sigcse2009/Makefile b/sigcse2009/Makefile
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+#
+# Simple makefile.
+# Uses pdflatex to produce PDF
+#
+BASE=sigcse2009
+
+$(BASE).pdf:   $(BASE).tex introduction.tex abstract.tex $(BASE).bib principles.tex assignments.tex
+       pdflatex $(BASE).tex
+       -bibtex $(BASE)
+       pdflatex $(BASE).tex
+       pdflatex $(BASE).tex
+

diff --git a/sigcse2009/abstract.tex b/sigcse2009/abstract.tex
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+
+Tend to write the abstract last.

diff --git a/sigcse2009/assignments.tex b/sigcse2009/assignments.tex
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+\section{Assignments}
+\label{sec:assignments}
+
+%
+% Not sure if we need that.
+%
+\subsection{Project 0}
+If Pintos is used in a semester-long course, project 0 serves as a ``warm-up'' project.
+In this project, students will gain familiarity with the Pintos source tree and some
+supporting classes, in particular its implementation of doubly-linked lists.
+In OS, doubly-linked lists are frequently used because they allow $O(1)$ insertion and
+removal operations.  Moreover, they are often used in a style in which the list cell
+containing the next and prev pointers is embedded in some larger structure, such as
+a thread control block, rather than having separately allocated list cells.
+In project 0, students use Pintos's list implementation to implement a simple, first-fit 
+memory allocator.  
+
+\subsection{Project 1 -- Threads}
+% intro
+Project 1 centers around threads.  The baseline Pintos code boots into a kernel that
+supports multiple in-kernel threads.  It provides code for initialization, thread creation and
+destruction, context switches, thread blocking and unblocking as well as a simple but
+preemptive round-robin scheduler.
+Students study the existing, barebones threading system (about 600 lines of C code) to 
+understand how threads are created and destroyed, and to understand the transitioning of 
+threads between the READY, RUNNING, and BLOCKED states.  They also study how a thread's
+internal memory is managed, which is used to store its runtime stack and thread control block.
+Student can examine the context switch code, but the projects do not involve any modifications
+to it.
+
+After reading the baseline code, the projects ask students to implement several features
+that exercise thread state transitions.  The first part of this project includes a simple
+alarm clock, which requires maintaining a timer queue of sleeping threads and changing 
+the timer interrupt handler to unblock those threads whose wakeup time has arrived.
+Students learn how to protect data structures that are shared between a thread and an
+interrupt handler.  The second part of the project constitutes a strict priority-based
+uniprocessor scheduler.  In this model, one of the threads with the highest priority
+always runs.  When a thread's priority changes, or when threads block or unblock,  
+a scheduling decision must be triggered to ensure this invariant.  Students learn about
+the different ways in which such situations occur.  
+Project 1 also introduces synchronization primitives such as semaphores, locks,
+and condition variables.  The project explores the interaction between such primitives,
+thread states, and the scheduler.
+
+Based on the priority scheduler, students implement two additional tasks: priority 
+inheritance and a multi-level feedback queue scheduler.  Priority inheritance is a way
+to avoid priority inversion, a phenonemon that most famously led to an almost-failure
+of the Mars Pathfinder Mission~\cite{MarsPathFinder}.  We use this example to motivate
+the problem.  Implementing priority inheritance correctly requires a deep understanding of the 
+interaction of threads and locks.
+Separately, students build a multi-level feedback queue scheduler on top of the strict
+priority scheduler.  This scheduler adjusts threads' priority based on a sampling  of how
+much CPU time a thread has received recently.
+
+\paragraph{Testing and Grading.}
+Project 1 is accompanied by about $XX$ tests, which are run using the Bochs simulator by
+a grading script.  Most tests are designed to test a single aspect, but some tests 
+test more involved scenarios.  Most of the tests are designed to produce a deterministic 
+output; the grading script will point out differences between the expected and the actual output. 
+Usually, a test failure leads students to study the documented source code of the test
+and understand how the expected output derives from it.
+
+The MLFQS scheduler tests are graded in a different way. Since those tests rely on estimating CPU
+usage, they depend on how much CPU time a specific implementation uses, which in turn depends on how
+efficient it is.  We compute the expected CPU consumption values by simulation and provide an
+envelope within which we accept the output.  The envelope is large enough to allow for minor
+inefficiencies, but major inefficiencies will usually lead to test failures.  Such failures
+convey the importance of using efficient algorithms and data structures within a kernel,
+because wasting CPU cycles in the kernel reduces the amount available to applications.
+
+% intro
+\paragraph{Learning Objectives.}
+Project 1 has three learning objectives.  First, students will understand how
+the illusion that ``computers can do multiple things at once'' is created by a sequence
+of thread state transitions and context switches.  Second, they will understand how
+a simple underlying mechanism - such as priority-based scheduling - can lead to more
+sophisticated scheduling policies.  Third, having seen the mechanisms a preemptive scheduler
+uses to create apparent concurrency, students gain a better intuition of the non-determinism
+inherent in concurrent systems. 
+
+%
+%
+%
+\subsection{Project 2 -- User Programs}
+The second project illustrates how OS implements protection and isolation between user processes,
+how user processes gain access to kernel services, and how user processes lay out the virtual
+address space in which their program and data is contained.
+The project adds support to Pintos to load and execute user programs that make use
+of kernel services.  We kept the provided code purposefully minimal, consisting of
+only a library that reads the program and data segments of ELF binaries.   These binaries
+are loaded into a new address space; the baseline code includes functionality to allocate
+physical memory and set up a page directory to establish the process's virtual address
+mappings.
+
+Students implement support for a small set of system calls that allow processes to perform
+I/O, start new processes, wait for their termination, and exit.  Both the Pintos user 
+process model and system call API are modeled after traditional Unix, with the exception 
+that Pintos processes do not separate process creation (i.e., fork()) from program loading
+(i.e., exec) - instead, Pintos's exec() system call combines these two pieces of functionality 
+into one.  The implementation of these calls requires the students to keep track of
+per-process resources such as file descriptors, deepening their understanding of how
+an operating system provides the abstraction of a process.
+
+Like most current OS, Pintos exploits dual-mode operation in which user processes run
+in a nonprivileged mode that prevents access to kernel resources and to resources allocated
+to other processes.  Processes attempting to bypass these restrictions are terminated.
+Students implement the system call handling code, a key aspect of which includes the
+careful examination of arguments passed by user processes.
+
+Project 2 also illustrates parallel programming techniques, notably fork/join
+parallelism, which students implement when providing support for the exec()/wait()/exit() 
+system calls.  The rendezvous-style synchronization necessary to support this model
+can be implemented using semaphores, providing a practical example of this style
+synchronization presented in accompanying lectures.
+
+% How threads extend into processes.
+
+\paragraph{Testing and Grading.}
+The tests for project 2 exclusively consist of user programs written in C.
+They are divided into functionality and robustness tests.  Functionality tests check that
+the operating system provides the expected set of services when it is used as
+expected.  A set of robustness tests checks that the OS rejects all attempts at passing
+invalid input to system calls.  To pass those tests, the student's kernel must be 
+``bullet-proof.'' We include a stress test in which we artificially induce low memory
+conditions by creating a large number of processes and pseudo-randomly introducing
+failures in some of them.  We expect the kernel to fully recover from such situations.
+
+\paragraph{Learning Objectives.}
+In project 2, students learn how the thread abstraction introduced in project 1 is 
+extended into the process abstraction, which combines a thread, a virtual address space, 
+and its associated resources.
+Project 2 enables students to understand how operating systems employ dual-mode
+operation to implement isolation between processes and to protect system resources
+even in the presence of failing or misbehaving processes.  
+Students understand how processes transition into the kernel to access its services,
+and how kernels implement such services in a robust way.
+The principles learned in this exercise carry over to all scenarios
+in which applications must be robust in the face of input coming from untrusted 
+sources and uncertain resource availability, as is the case in many server systems.
+
+\subsection{Project 3}
+Project 3 asks students to implement several virtual memory techniques, including
+on-demand paging of programs, stack growth, page replacement, and memory-mapped files.
+This functionality is implemented in a page fault service handler and during the
+program loading process.
+We provide supporting code to create and maintain page directories, which hide
+the x86-specifics of how to program the memory management unit (MMU) and how
+to ensure consistency with the CPU's translation look-aside buffer (TLB).  
+As a result, students can treat the MMU as an abstract device in which to 
+install, update, or remove virtual to physical address mappings.
+Consequently, they are free to choose any design for the data structures needed to
+keep track of the state of each page or region in a process's virtual address 
+space.
+
+In early offerings, this significant creative freedom came at the cost that 
+some students were lost as how to accomplish set goals.  We added an intermediate
+design review stage to this projects using a structured questionnaire in which students 
+outline their planned design.  We also provide a suggested order of implementation.
+
+Like project 2, project 3 requires reasoning using parallel programming strategies.  
+Since the Pintos kernel is fully preemptive, students must consider which data structures
+require locking, and the must design a locking strategy that both avoids deadlock
+and reduces unnecessary serialization.
+
+\paragraph{Testing and Grading.}
+Project 3 relies on project 2, therefore, we include all tests provided with project 2
+as regression tests to ensure that system call functionality does not break in the
+presence of virtual memory.  Furthermore, we provide functionality tests for the
+added functionality that lends itself to such testing, namely, memory-mapped files
+and stack growth.  Some of the project tasks, such as on-demand paging, are 
+performance-enhancing techniques that do not directly add functionality that is
+apparent to user programs, which are graded by inspection.  We test the students
+page replacement code by varying the amount of physical memory available to
+the kernel when run under emulation, relative to the amount of memory that is 
+accessed by our test programs.  Timeouts are used to detect grossly inefficient 
+page replacement schemes.
+
+\paragraph{Learning Objectives.}
+In project 3, students learn how an OS creates the environment in which a user
+program executes, specifically as it relates to code and variables used in a program.
+It provides a deep understanding of how OS use fault resumption to
+to virtualize a process's interaction with physical memory.
+In addition, students gain hands-on experience with page replacement algorithms
+and have the opportunity to observe their performance impact.
+
+%
+%
+%
+\subsection{Project 4}
+\paragraph{Testing and Grading.}
+\paragraph{Learning Objectives.}
+

diff --git a/sigcse2009/getcites.sh b/sigcse2009/getcites.sh
new file mode 100755 (executable)
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+++ b/sigcse2009/getcites.sh
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+#!/bin/bash
+#
+# This script downloads the bibtex file for group 'pintos' (6404) from citeulike.org
+# To add a reference, simply post it to citeulike and make sure it's included 
+# in group 'pintos'
+#
+# To run this script, you need to have your cookies stored in a file called "citeulikecookies.txt"
+#
+/bin/mv -f sigcse2009.bib sigcse2009.bib.old
+wget -O _sigcse2009.bib \
+    --load-cookies citeulikecookies.txt \
+    'http://www.citeulike.org/bibtex/group/6404?do_username_prefix=0&key_type=4'
+
+cat - _sigcse2009.bib > sigcse2009.bib << EOF
+%
+% This file is automatically generated by citeulike.org
+%
+EOF
+/bin/rm -rf _sigcse2009.bib
+

diff --git a/sigcse2009/introduction.tex b/sigcse2009/introduction.tex
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+\section{Introduction}
+\label{sec:intro}
+
+Despite the wide use of higher-level languages and environments, gaining a robust
+understanding of operating systems (OS) fundamentals and training in the current design and
+implementation practices of operating systems remains a cornerstone goal of 
+undergraduate computer science education.
+
+% abstract/concrete
+% internal/external
+Approaches to teaching such a course generally fall along two axes: 
+whether the treatment of the material is abstract or 
+concrete~\cite{Hovemeyer2004Running}, and whether they adopt an
+internal or external perspective~\cite{Deitel2003Operating}.
+An abstract approach discusses algorithms and techniques used in operating 
+systems and may include partial implementation or simulation exercises,
+whereas a concrete approach stresses the design and creation of 
+realistic artifacts.
+When adopting the internal perspective, an operating system is considered
+from the point of view of the OS designer, whereas the external perspective 
+assumes the role of a user or programmer using an OS's 
+facilities~\cite{Bryant2002Computer}.
+
+% is this too controversial for this audience?
+The approach advocated in this paper adopts a concrete approach and the internal
+perspective.  Students who have been in the role of an
+OS designer bring a better understanding of how to use one; and students
+who have both studied, implemented, and evaluated core OS techniques obtain 
+a deeper understanding than those who have merely studied them.
+Finally, adopting a concrete approach brings significant secondary
+benefits, including training in modern software development techniques
+and tools.  The C language remains the implementation language of choice
+for operating system kernels and for many embedded systems.
+Practice and debugging skills in C, particularly using modern tools,
+not only increases students' ``market value,'' but provides students with
+the insight that a low-level programming and runtime model is not incompatible
+with high-level tools.
+
+Designing course material for the internal and concrete 
+approach is challenging for several reasons.  While realistic, assignments should be
+relatively simple and doable within a realistic time frame.  
+Whereas assignments should use current hardware architectures, 
+they must not impart too much knowledge that is transient.
+Assignments should include and emphasize the use of modern software 
+engineering practices and tools, such as dynamic program analysis.
+
+This paper introduces Pintos, an instructional operating system kernel that 
+has been in use at several institutions for about 4 years.  Pintos provides 
+a bootable kernel for standard personal computers.  We provide several
+structured assignments in which students implement a basic priority
+scheduler, a multi-level feedback queue scheduler, the ability to
+load programs and support a set of system calls, page-based virtual memory
+including on-demand paging, memory-mapped files, and swapping, and a
+simple hierarchical file system.  
+
+Although Pintos follows in the tradition of instructional operating systems 
+such as Nachos~\cite{Christopher1993Nachos}, 
+GeekOS~\cite{Hovemeyer2004Running}, 
+and OS/161~\cite{Holland2002New}, we believe that it is unique in two
+aspects.  First, Pintos runs on both real hardware and in emulated and
+simulated environments.  Second, we have created a set of analysis tools
+for the emulated environment that allows students to detect programming
+mistakes such as race conditions.
+
+This paper reports on the design philosophy that underlies Pintos,
+details its structure, and outline the nature and learning goals of each
+assignment.
+ 
+% Challenges.
+% How to embed principles?
+% How to teach software engineering?
+% Realism vs. Simplification

diff --git a/sigcse2009/principles.tex b/sigcse2009/principles.tex
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+\section{Design Principles}
+\label{sec:designprinciples}
+
+The Pintos series of projects are built on a number of principles.
+
+\paragraph{Read before You code.}
+Each project involves a significant amount of reading code before
+students write the first line of their code.  
+Because software maintenance constitutes the vast majority of all
+software development efforts~\cite{askEliforcite}, this setup mirrors the 
+environment in which most software engineers work.
+We went to great lengths to write the entire Pintos baseline code,
+and in particular the portions students will read, in a style that shows,
+by example, the coding style we expect from students.  This style
+includes purely syntactical convention such as the choice of the
+GNU indentation style, and extends to commenting style and naming 
+conventions.  During the semesters in which Pintos was used, we
+continuously refined the internal code documentation, focusing on those 
+portions that initially proved difficult to understand or confusing.
+
+\paragraph{Maximize Creative Freedom}
+OS design involves a tremendous amount of creative freedom, both in the
+choice of algorithm and data structures.  Our projects are designed to
+stimulate creativity by avoiding the prescription of specific approaches
+to accomplish each project's goals.  Instead, students must design their
+own data structures and associated algorithms as much as possible.
+
+\paragraph{Practice Test-driven Development}
+%Test-driven development~\cite{Edwards}
+Each project includes a large number of test cases that is accessible
+to students.  In keeping with us adopting an internal perspective, students 
+do not develop test cases, rather, they must implement the API that is exercised
+by these test cases.
+
+\paragraph{Work in a Team}
+The projects presented in this paper are designed to be accomplished by teams of 
+2-4 students.  Working in a team provides an environment that more closely resembles
+industrial software development, and it provides a way for students brainstorm and
+implement together.  In addition, we teach and require the use of group collaboration tools,
+notably shared source code version control systems such as CVS.
+
+\paragraph{Justify your Design}
+Design justification and rationale is as important for learning as creating an artifact 
+that fulfill a set of given requirements.  We designed a set of structured questionnaires 
+in which students describe their design and discuss choices and trade-offs they made.
+
+\paragraph{Provide a reproducible, manageable environment.}
+Some concurrent environments are difficult to manage and debug.  
+
+Teaching OS involves teaching concurrency
+
+Operating systems are fundamentally
+
+\paragraph{Provide analysis tools.}

diff --git a/sigcse2009/rest.tex b/sigcse2009/rest.tex
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+\section{Rest of paper}
+
+philosophy
+
+\section{Future Work}
+
+Pintos doesn't do SMP or multicore.
+Pintos doesn't do IPC.
+Pintos doesn't do networking.

diff --git a/sigcse2009/sig-alternate.cls b/sigcse2009/sig-alternate.cls
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+% SIG-ALTERNATE.CLS - VERSION 2.3\r
+% "COMPATIBLE" WITH THE "ACM_PROC_ARTICLE-SP.CLS" V3.1SP\r
+% Gerald Murray June 7th. 2007\r
+%\r
+% ---- Start of 'updates'  ----\r
+%\r
+% To produce Type 1 fonts in the document plus allow for 'normal LaTeX accenting' in the critical areas;\r
+% title, author block, section-heads, confname, etc. etc. \r
+% i.e. the whole purpose of this version update is to NOT resort to 'inelegant accent patches'.\r
+% After much research, three extra .sty packages were added to the the tail (ae, aecompl, aeguill) to solve,\r
+% in particular, the accenting problem(s). We _could_ ask authors (via instructions/sample file) to 'include' these in\r
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+% then this is less work for authors and also makes everything appear 'vanilla'.\r
+% NOTE: all 'patchwork accenting" has been commented out (here) and is no longer 'used' in the sample .tex file (either).\r
+% Gerry June 2007\r
+%\r
+% Patch for accenting in conference name/location. Gerry May 3rd. 2007\r
+% Rule widths changed to .5, author count (>6) fixed, roll-back for Type 3 problem. Gerry March 20th. 2007\r
+% Changes made to 'modernize' the fontnames but esp. for MikTeX users V2.4/2.5 - Nov. 30th. 2006\r
+% Updated the \email definition to allow for its use inside of 'shared affiliations' - Nov. 30th. 2006\r
+% Fixed the 'section number depth value' - Nov. 30th. 2006\r
+%\r
+% Footnotes inside table cells using \minipage (Oct. 2002)\r
+% Georgia fixed bug in sub-sub-section numbering in paragraphs (July 29th. 2002)\r
+% JS/GM fix to vertical spacing before Proofs (July 30th. 2002)\r
+%\r
+% Made the Permission Statement / Conference Info / Copyright Info\r
+% 'user definable' in the source .tex file OR automatic if\r
+% not specified.\r
+%\r
+% Allowance made to switch default fonts between those systems using\r
+% normal/modern font names and those using 'Type 1' or 'Truetype' fonts.\r
+% See LINE NUMBER 255 for details.\r
+% Also provided for enumerated/annotated Corollaries 'surrounded' by\r
+% enumerated Theorems (line 848).\r
+% Gerry November 11th. 1999\r
+%\r
+% ---- End of 'updates' ----\r
+%\r
+\def\fileversion{v2.3}          % for ACM's tracking purposes\r
+\def\filedate{June 7, 2007}    % Gerry Murray's tracking data\r
+\def\docdate {Thursday 7th. June 2007} % Gerry Murray (with deltas to doc}\r
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+\usepackage{amssymb}\r
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+%\usepackage[T1]{fontenc}  % Gerry March 12, 2007 - causes Type 3 problems (body text)\r
+%\usepackage{textcomp}\r
+%\r
+% SIG-ALTERNATE DOCUMENT STYLE\r
+% G.K.M. Tobin August-October 1999\r
+%    adapted from ARTICLE document style by Ken Traub, Olin Shivers\r
+%    also using elements of esub2acm.cls\r
+% HEAVILY MODIFIED, SUBSEQUENTLY, BY GERRY MURRAY 2000\r
+% ARTICLE DOCUMENT STYLE -- Released 16 March 1988\r
+%    for LaTeX version 2.09\r
+% Copyright (C) 1988 by Leslie Lamport\r
+%\r
+%\r
+%%% sig-alternate.cls is an 'ALTERNATE' document style for producing\r
+%%% two-column camera-ready pages for ACM conferences.\r
+%%% THIS FILE DOES NOT STRICTLY ADHERE TO THE SIGS (BOARD-ENDORSED)\r
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+%%% The main features of this style are:\r
+%%%\r
+%%% 1)  Two columns.\r
+%%% 2)  Side and top margins of 4.5pc, bottom margin of 6pc, column gutter of\r
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+%%% 4)  Text is 9pt on 10pt baselines; titles (except main) are 9pt bold.\r
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+%%% There are a few restrictions you must observe:\r
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+%%% You may turn this hackery off via the -e option:\r
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+\typeout{Document Class 'sig-alternate' <7th. June '07>.  Modified by G.K.M. Tobin/Gerry Murray}\r
+\typeout{Based in part upon document Style `acmconf' <22 May 89>. Hacked 4/91 by}\r
+\typeout{shivers@cs.cmu.edu, 4/93 by theobald@cs.mcgill.ca}\r
+\typeout{Excerpts were taken from (Journal Style) 'esub2acm.cls'.}\r
+\typeout{****** Bugs/comments/suggestions/technicalities to Gerry Murray -- murray@hq.acm.org ******}\r
+\typeout{Questions on the style, SIGS policies, etc. to Adrienne Griscti griscti@acm.org}\r
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+%% are OK as is. Olin.\r
+\advance\topmargin by -37pt     % Leave 37pt above text for headers\r
+\headheight 12pt                % Height of box containing running head.\r
+\headsep 25pt                   % Space between running head and text.\r
+\r
+\textheight 666pt       % 9 1/4 column height\r
+\textwidth 42pc         % Width of text line.\r
+                        % For two-column mode:\r
+\columnsep 2pc          %    Space between columns\r
+\columnseprule 0pt      %    Width of rule between columns.\r
+\hfuzz 1pt              % Allow some variation in column width, otherwise it's\r
+                        % too hard to typeset in narrow columns.\r
+\r
+\footnotesep 5.6pt      % Height of strut placed at the beginning of every\r
+                        % footnote =3D height of normal \footnotesize strut,\r
+                        % so no extra space between footnotes.\r
+\r
+\skip\footins 8.1pt plus 4pt minus 2pt  % Space between last line of text and\r
+                                        % top of first footnote.\r
+\floatsep 11pt plus 2pt minus 2pt       % Space between adjacent floats moved\r
+                                        % to top or bottom of text page.\r
+\textfloatsep 18pt plus 2pt minus 4pt   % Space between main text and floats\r
+                                        % at top or bottom of page.\r
+\intextsep 11pt plus 2pt minus 2pt      % Space between in-text figures and\r
+                                        % text.\r
+\@ifundefined{@maxsep}{\newdimen\@maxsep}{}% this is for LaTeX2e\r
+\@maxsep 18pt                           % The maximum of \floatsep,\r
+                                        % \textfloatsep and \intextsep (minus\r
+                                        % the stretch and shrink).\r
+\dblfloatsep 11pt plus 2pt minus 2pt    % Same as \floatsep for double-column\r
+                                        % figures in two-column mode.\r
+\dbltextfloatsep 18pt plus 2pt minus 4pt% \textfloatsep for double-column\r
+                                        % floats.\r
+\@ifundefined{@dblmaxsep}{\newdimen\@dblmaxsep}{}% this is for LaTeX2e\r
+\@dblmaxsep 18pt                        % The maximum of \dblfloatsep and\r
+                                        % \dbltexfloatsep.\r
+\@fptop 0pt plus 1fil    % Stretch at top of float page/column. (Must be\r
+                         % 0pt plus ...)\r
+\@fpsep 8pt plus 2fil    % Space between floats on float page/column.\r
+\@fpbot 0pt plus 1fil    % Stretch at bottom of float page/column. (Must be\r
+                         % 0pt plus ... )\r
+\@dblfptop 0pt plus 1fil % Stretch at top of float page. (Must be 0pt plus ...)\r
+\@dblfpsep 8pt plus 2fil % Space between floats on float page.\r
+\@dblfpbot 0pt plus 1fil % Stretch at bottom of float page. (Must be\r
+                         % 0pt plus ... )\r
+\marginparpush 5pt       % Minimum vertical separation between two marginal\r
+                         % notes.\r
+\r
+\parskip 0pt plus 1pt            % Extra vertical space between paragraphs.\r
+\parindent 9pt  % GM July 2000 / was 0pt - width of paragraph indentation.\r
+\partopsep 2pt plus 1pt minus 1pt% Extra vertical space, in addition to\r
+                                 % \parskip and \topsep, added when user\r
+                                 % leaves blank line before environment.\r
+\r
+\@lowpenalty   51       % Produced by \nopagebreak[1] or \nolinebreak[1]\r
+\@medpenalty  151       % Produced by \nopagebreak[2] or \nolinebreak[2]\r
+\@highpenalty 301       % Produced by \nopagebreak[3] or \nolinebreak[3]\r
+\r
+\@beginparpenalty -\@lowpenalty % Before a list or paragraph environment.\r
+\@endparpenalty   -\@lowpenalty % After a list or paragraph environment.\r
+\@itempenalty     -\@lowpenalty % Between list items.\r
+\r
+\@namedef{ds@10pt}{\@latexerr{The `10pt' option is not allowed in the `acmconf'\r
+  document style.}\@eha}\r
+\@namedef{ds@11pt}{\@latexerr{The `11pt' option is not allowed in the `acmconf'\r
+  document style.}\@eha}\r
+\@namedef{ds@12pt}{\@latexerr{The `12pt' option is not allowed in the `acmconf'\r
+  document style.}\@eha}\r
+\r
+\@options\r
+\r
+\lineskip 2pt           % \lineskip is 1pt for all font sizes.\r
+\normallineskip 2pt\r
+\def\baselinestretch{1}\r
+\r
+\abovedisplayskip 9pt plus2pt minus4.5pt%\r
+\belowdisplayskip \abovedisplayskip\r
+\abovedisplayshortskip  \z@ plus3pt%\r
+\belowdisplayshortskip  5.4pt plus3pt minus3pt%\r
+\let\@listi\@listI     % Setting of \@listi added 9 Jun 87\r
+\r
+\def\small{\@setsize\small{9pt}\viiipt\@viiipt\r
+\abovedisplayskip 7.6pt plus 3pt minus 4pt%\r
+\belowdisplayskip \abovedisplayskip\r
+\abovedisplayshortskip \z@ plus2pt%\r
+\belowdisplayshortskip 3.6pt plus2pt minus 2pt\r
+\def\@listi{\leftmargin\leftmargini %% Added 22 Dec 87\r
+\topsep 4pt plus 2pt minus 2pt\parsep 2pt plus 1pt minus 1pt\r
+\itemsep \parsep}}\r
+\r
+\def\footnotesize{\@setsize\footnotesize{9pt}\ixpt\@ixpt\r
+\abovedisplayskip 6.4pt plus 2pt minus 4pt%\r
+\belowdisplayskip \abovedisplayskip\r
+\abovedisplayshortskip \z@ plus 1pt%\r
+\belowdisplayshortskip 2.7pt plus 1pt minus 2pt\r
+\def\@listi{\leftmargin\leftmargini %% Added 22 Dec 87\r
+\topsep 3pt plus 1pt minus 1pt\parsep 2pt plus 1pt minus 1pt\r
+\itemsep \parsep}}\r
+\r
+\newcount\aucount\r
+\newcount\originalaucount\r
+\newdimen\auwidth\r
+\auwidth=\textwidth\r
+\newdimen\auskip\r
+\newcount\auskipcount\r
+\newdimen\auskip\r
+\global\auskip=1pc\r
+\newdimen\allauboxes\r
+\allauboxes=\auwidth\r
+\newtoks\addauthors\r
+\newcount\addauflag\r
+\global\addauflag=0 %Haven't shown additional authors yet\r
+\r
+\newtoks\subtitletext\r
+\gdef\subtitle#1{\subtitletext={#1}}\r
+\r
+\gdef\additionalauthors#1{\addauthors={#1}}\r
+\r
+\gdef\numberofauthors#1{\global\aucount=#1\r
+\ifnum\aucount>3\global\originalaucount=\aucount \global\aucount=3\fi %g}  % 3 OK - Gerry March 2007\r
+\global\auskipcount=\aucount\global\advance\auskipcount by 1\r
+\global\multiply\auskipcount by 2\r
+\global\multiply\auskip by \auskipcount\r
+\global\advance\auwidth by -\auskip\r
+\global\divide\auwidth by \aucount}\r
+\r
+% \and was modified to count the number of authors.  GKMT 12 Aug 1999\r
+\def\alignauthor{%                  % \begin{tabular}\r
+\end{tabular}%\r
+  \begin{tabular}[t]{p{\auwidth}}\centering}%\r
+\r
+%  *** NOTE *** NOTE *** NOTE *** NOTE ***\r
+%  If you have 'font problems' then you may need\r
+%  to change these, e.g. 'arialb' instead of "arialbd".\r
+%  Gerry Murray 11/11/1999\r
+%  *** OR ** comment out block A and activate block B or vice versa.\r
+% **********************************************\r
+%\r
+%  -- Start of block A -- (Type 1 or Truetype fonts)\r
+%\newfont{\secfnt}{timesbd at 12pt} % was timenrb originally - now is timesbd\r
+%\newfont{\secit}{timesbi at 12pt}   %13 Jan 00 gkmt\r
+%\newfont{\subsecfnt}{timesi at 11pt} % was timenrri originally - now is timesi\r
+%\newfont{\subsecit}{timesbi at 11pt} % 13 Jan 00 gkmt -- was times changed to timesbi gm 2/4/2000\r
+%                         % because "normal" is italic, "italic" is Roman\r
+%\newfont{\ttlfnt}{arialbd at 18pt} % was arialb originally - now is arialbd\r
+%\newfont{\ttlit}{arialbi at 18pt}    % 13 Jan 00 gkmt\r
+%\newfont{\subttlfnt}{arial at 14pt} % was arialr originally - now is arial\r
+%\newfont{\subttlit}{ariali at 14pt} % 13 Jan 00 gkmt\r
+%\newfont{\subttlbf}{arialbd at 14pt}  % 13 Jan 00 gkmt\r
+%\newfont{\aufnt}{arial at 12pt} % was arialr originally - now is arial\r
+%\newfont{\auit}{ariali at 12pt} % 13 Jan 00 gkmt\r
+%\newfont{\affaddr}{arial at 10pt} % was arialr originally - now is arial\r
+%\newfont{\affaddrit}{ariali at 10pt} %13 Jan 00 gkmt\r
+%\newfont{\eaddfnt}{arial at 12pt} % was arialr originally - now is arial\r
+%\newfont{\ixpt}{times at 9pt} % was timenrr originally - now is times\r
+%\newfont{\confname}{timesi at 8pt} % was timenrri - now is timesi\r
+%\newfont{\crnotice}{times at 8pt} % was timenrr originally - now is times\r
+%\newfont{\ninept}{times at 9pt} % was timenrr originally - now is times\r
+\r
+% *********************************************\r
+%  -- End of block A --\r
+%\r
+%\r
+% -- Start of block B -- UPDATED FONT NAMES\r
+% *********************************************\r
+% Gerry Murray 11/30/2006\r
+% *********************************************\r
+\newfont{\secfnt}{ptmb8t at 12pt}\r
+\newfont{\secit}{ptmbi8t at 12pt}    %13 Jan 00 gkmt\r
+\newfont{\subsecfnt}{ptmri8t at 11pt}\r
+\newfont{\subsecit}{ptmbi8t at 11pt}  % \r
+\newfont{\ttlfnt}{phvb8t at 18pt}\r
+\newfont{\ttlit}{phvbo8t at 18pt}    % GM 2/4/2000\r
+\newfont{\subttlfnt}{phvr8t at 14pt}\r
+\newfont{\subttlit}{phvro8t at 14pt} % GM 2/4/2000\r
+\newfont{\subttlbf}{phvb8t at 14pt}  % 13 Jan 00 gkmt\r
+\newfont{\aufnt}{phvr8t at 12pt}\r
+\newfont{\auit}{phvro8t at 12pt}     % GM 2/4/2000\r
+\newfont{\affaddr}{phvr8t at 10pt}\r
+\newfont{\affaddrit}{phvro8t at 10pt} % GM 2/4/2000\r
+\newfont{\eaddfnt}{phvr8t at 12pt}\r
+\newfont{\ixpt}{ptmr8t at 9pt}\r
+\newfont{\confname}{ptmri8t at 8pt}\r
+\newfont{\crnotice}{ptmr8t at 8pt}\r
+\newfont{\ninept}{ptmr8t at 9pt}\r
+% +++++++++++++++++++++++++++++++++++++++++++++\r
+% -- End of block B --\r
+\r
+%\def\email#1{{{\eaddfnt{\vskip 4pt#1}}}}\r
+% If we have an email, inside a "shared affiliation" then we need the following instead\r
+\def\email#1{{{\eaddfnt{\par #1}}}}       % revised  - GM - 11/30/2006\r
+\r
+\def\addauthorsection{\ifnum\originalaucount>6  % was 3 - Gerry March 2007\r
+    \section{Additional Authors}\the\addauthors\r
+  \fi}\r
+\r
+\newcount\savesection\r
+\newcount\sectioncntr\r
+\global\sectioncntr=1\r
+\r
+\setcounter{secnumdepth}{3}\r
+\r
+\def\appendix{\par\r
+\section*{APPENDIX}\r
+\setcounter{section}{0}\r
+ \setcounter{subsection}{0}\r
+ \def\thesection{\Alph{section}} }\r
+\r
+\leftmargini 22.5pt\r
+\leftmarginii 19.8pt    % > \labelsep + width of '(m)'\r
+\leftmarginiii 16.8pt   % > \labelsep + width of 'vii.'\r
+\leftmarginiv 15.3pt    % > \labelsep + width of 'M.'\r
+\leftmarginv 9pt\r
+\leftmarginvi 9pt\r
+\r
+\leftmargin\leftmargini\r
+\labelsep 4.5pt\r
+\labelwidth\leftmargini\advance\labelwidth-\labelsep\r
+\r
+\def\@listI{\leftmargin\leftmargini \parsep 3.6pt plus 2pt minus 1pt%\r
+\topsep 7.2pt plus 2pt minus 4pt%\r
+\itemsep 3.6pt plus 2pt minus 1pt}\r
+\r
+\let\@listi\@listI\r
+\@listi\r
+\r
+\def\@listii{\leftmargin\leftmarginii\r
+   \labelwidth\leftmarginii\advance\labelwidth-\labelsep\r
+   \topsep 3.6pt plus 2pt minus 1pt\r
+   \parsep 1.8pt plus 0.9pt minus 0.9pt\r
+   \itemsep \parsep}\r
+\r
+\def\@listiii{\leftmargin\leftmarginiii\r
+    \labelwidth\leftmarginiii\advance\labelwidth-\labelsep\r
+    \topsep 1.8pt plus 0.9pt minus 0.9pt\r
+    \parsep \z@ \partopsep 1pt plus 0pt minus 1pt\r
+    \itemsep \topsep}\r
+\r
+\def\@listiv{\leftmargin\leftmarginiv\r
+     \labelwidth\leftmarginiv\advance\labelwidth-\labelsep}\r
+\r
+\def\@listv{\leftmargin\leftmarginv\r
+     \labelwidth\leftmarginv\advance\labelwidth-\labelsep}\r
+\r
+\def\@listvi{\leftmargin\leftmarginvi\r
+     \labelwidth\leftmarginvi\advance\labelwidth-\labelsep}\r
+\r
+\def\labelenumi{\theenumi.}\r
+\def\theenumi{\arabic{enumi}}\r
+\r
+\def\labelenumii{(\theenumii)}\r
+\def\theenumii{\alph{enumii}}\r
+\def\p@enumii{\theenumi}\r
+\r
+\def\labelenumiii{\theenumiii.}\r
+\def\theenumiii{\roman{enumiii}}\r
+\def\p@enumiii{\theenumi(\theenumii)}\r
+\r
+\def\labelenumiv{\theenumiv.}\r
+\def\theenumiv{\Alph{enumiv}}\r
+\def\p@enumiv{\p@enumiii\theenumiii}\r
+\r
+\def\labelitemi{$\bullet$}\r
+\def\labelitemii{\bf --}\r
+\def\labelitemiii{$\ast$}\r
+\def\labelitemiv{$\cdot$}\r
+\r
+\def\verse{\let\\=\@centercr\r
+  \list{}{\itemsep\z@ \itemindent -1.5em\listparindent \itemindent\r
+          \rightmargin\leftmargin\advance\leftmargin 1.5em}\item[]}\r
+\let\endverse\endlist\r
+\r
+\def\quotation{\list{}{\listparindent 1.5em\r
+    \itemindent\listparindent\r
+    \rightmargin\leftmargin \parsep 0pt plus 1pt}\item[]}\r
+\let\endquotation=\endlist\r
+\r
+\def\quote{\list{}{\rightmargin\leftmargin}\item[]}\r
+\let\endquote=\endlist\r
+\r
+\def\descriptionlabel#1{\hspace\labelsep \bf #1}\r
+\def\description{\list{}{\labelwidth\z@ \itemindent-\leftmargin\r
+       \let\makelabel\descriptionlabel}}\r
+\r
+\let\enddescription\endlist\r
+\r
+\def\theequation{\arabic{equation}}\r
+\r
+\arraycolsep 4.5pt   % Half the space between columns in an array environment.\r
+\tabcolsep 5.4pt    % Half the space between columns in a tabular environment.\r
+\arrayrulewidth .5pt % Width of rules in array and tabular environment. % (was .4) updated Gerry March 20 2007\r
+\doublerulesep 1.8pt % Space between adjacent rules in array or tabular env.\r
+\r
+\tabbingsep \labelsep   % Space used by the \' command.  (See LaTeX manual.)\r
+\r
+\skip\@mpfootins =\skip\footins\r
+\r
+\fboxsep =2.7pt      % Space left between box and text by \fbox and \framebox.\r
+\fboxrule =.5pt      % Width of rules in box made by \fbox and \framebox. % (was .4) updated Gerry March 20 2007\r
+\r
+\def\thepart{\Roman{part}} % Roman numeral part numbers.\r
+\def\thesection       {\arabic{section}}\r
+\def\thesubsection    {\thesection.\arabic{subsection}}\r
+%\def\thesubsubsection {\thesubsection.\arabic{subsubsection}} % GM 7/30/2002\r
+%\def\theparagraph     {\thesubsubsection.\arabic{paragraph}}  % GM 7/30/2002\r
+\def\thesubparagraph  {\theparagraph.\arabic{subparagraph}}\r
+\r
+\def\@pnumwidth{1.55em}\r
+\def\@tocrmarg {2.55em}\r
+\def\@dotsep{4.5}\r
+\setcounter{tocdepth}{3}\r
+\r
+\def\tableofcontents{\@latexerr{\tableofcontents: Tables of contents are not\r
+  allowed in the `acmconf' document style.}\@eha}\r
+\r
+\def\l@part#1#2{\addpenalty{\@secpenalty}\r
+   \addvspace{2.25em plus 1pt}  % space above part line\r
+   \begingroup\r
+   \@tempdima 3em       % width of box holding part number, used by\r
+     \parindent \z@ \rightskip \@pnumwidth      %% \numberline\r
+     \parfillskip -\@pnumwidth\r
+     {\large \bf        % set line in \large boldface\r
+     \leavevmode        % TeX command to enter horizontal mode.\r
+     #1\hfil \hbox to\@pnumwidth{\hss #2}}\par\r
+     \nobreak           % Never break after part entry\r
+   \endgroup}\r
+\r
+\def\l@section#1#2{\addpenalty{\@secpenalty} % good place for page break\r
+   \addvspace{1.0em plus 1pt}   % space above toc entry\r
+   \@tempdima 1.5em             % width of box holding section number\r
+   \begingroup\r
+    \parindent  \z@ \rightskip \@pnumwidth\r
+     \parfillskip -\@pnumwidth\r
+     \bf                        % Boldface.\r
+     \leavevmode                % TeX command to enter horizontal mode.\r
+      \advance\leftskip\@tempdima %% added 5 Feb 88 to conform to\r
+      \hskip -\leftskip           %% 25 Jan 88 change to \numberline\r
+     #1\nobreak\hfil \nobreak\hbox to\@pnumwidth{\hss #2}\par\r
+   \endgroup}\r
+\r
+\r
+\def\l@subsection{\@dottedtocline{2}{1.5em}{2.3em}}\r
+\def\l@subsubsection{\@dottedtocline{3}{3.8em}{3.2em}}\r
+\def\l@paragraph{\@dottedtocline{4}{7.0em}{4.1em}}\r
+\def\l@subparagraph{\@dottedtocline{5}{10em}{5em}}\r
+\r
+\def\listoffigures{\@latexerr{\listoffigures: Lists of figures are not\r
+  allowed in the `acmconf' document style.}\@eha}\r
+\r
+\def\l@figure{\@dottedtocline{1}{1.5em}{2.3em}}\r
+\r
+\def\listoftables{\@latexerr{\listoftables: Lists of tables are not\r
+  allowed in the `acmconf' document style.}\@eha}\r
+\let\l@table\l@figure\r
+\r
+\def\footnoterule{\kern-3\p@\r
+  \hrule width .5\columnwidth   % (was .4) updated Gerry March 20 2007\r
+  \kern 2.6\p@}                 % The \hrule has default height of .4pt % (was .4) updated Gerry March 20 2007\r
+% ------\r
+\long\def\@makefntext#1{\noindent \r
+%\hbox to .5em{\hss$^{\@thefnmark}$}#1}   % original\r
+\hbox to .5em{\hss\textsuperscript{\@thefnmark}}#1}  % C. Clifton / GM Oct. 2nd. 2002\r
+% -------\r
+\r
+\long\def\@maketntext#1{\noindent\r
+#1}\r
+\r
+\long\def\@maketitlenotetext#1#2{\noindent\r
+            \hbox to 1.8em{\hss$^{#1}$}#2}\r
+\r
+\setcounter{topnumber}{2}\r
+\def\topfraction{.7}\r
+\setcounter{bottomnumber}{1}\r
+\def\bottomfraction{.3}\r
+\setcounter{totalnumber}{3}\r
+\def\textfraction{.2}\r
+\def\floatpagefraction{.5}\r
+\setcounter{dbltopnumber}{2}\r
+\def\dbltopfraction{.7}\r
+\def\dblfloatpagefraction{.5}\r
+\r
+%\r
+\long\def\@makecaption#1#2{\r
+   \vskip \baselineskip\r
+   \setbox\@tempboxa\hbox{\textbf{#1: #2}}\r
+   \ifdim \wd\@tempboxa >\hsize % IF longer than one line:\r
+       \textbf{#1: #2}\par               %   THEN set as ordinary paragraph.\r
+     \else                      %   ELSE  center.\r
+       \hbox to\hsize{\hfil\box\@tempboxa\hfil}\par\r
+   \fi}\r
+\r
+%\r
+\r
+\long\def\@makecaption#1#2{\r
+   \vskip 10pt\r
+   \setbox\@tempboxa\hbox{\textbf{#1: #2}}\r
+   \ifdim \wd\@tempboxa >\hsize % IF longer than one line:\r
+       \textbf{#1: #2}\par                %   THEN set as ordinary paragraph.\r
+     \else                      %   ELSE  center.\r
+       \hbox to\hsize{\hfil\box\@tempboxa\hfil}\r
+   \fi}\r
+\r
+\@ifundefined{figure}{\newcounter {figure}} % this is for LaTeX2e\r
+\r
+\def\fps@figure{tbp}\r
+\def\ftype@figure{1}\r
+\def\ext@figure{lof}\r
+\def\fnum@figure{Figure \thefigure}\r
+\def\figure{\@float{figure}}\r
+\let\endfigure\end@float\r
+\@namedef{figure*}{\@dblfloat{figure}}\r
+\@namedef{endfigure*}{\end@dblfloat}\r
+\r
+\@ifundefined{table}{\newcounter {table}} % this is for LaTeX2e\r
+\r
+\def\fps@table{tbp}\r
+\def\ftype@table{2}\r
+\def\ext@table{lot}\r
+\def\fnum@table{Table \thetable}\r
+\def\table{\@float{table}}\r
+\let\endtable\end@float\r
+\@namedef{table*}{\@dblfloat{table}}\r
+\@namedef{endtable*}{\end@dblfloat}\r
+\r
+\newtoks\titleboxnotes\r
+\newcount\titleboxnoteflag\r
+\r
+\def\maketitle{\par\r
+ \begingroup\r
+   \def\thefootnote{\fnsymbol{footnote}}\r
+   \def\@makefnmark{\hbox\r
+       to 0pt{$^{\@thefnmark}$\hss}}\r
+     \twocolumn[\@maketitle]\r
+\@thanks\r
+ \endgroup\r
+ \setcounter{footnote}{0}\r
+ \let\maketitle\relax\r
+ \let\@maketitle\relax\r
+ \gdef\@thanks{}\gdef\@author{}\gdef\@title{}\gdef\@subtitle{}\let\thanks\relax\r
+ \@copyrightspace}\r
+\r
+%% CHANGES ON NEXT LINES\r
+\newif\if@ll % to record which version of LaTeX is in use\r
+\r
+\expandafter\ifx\csname LaTeXe\endcsname\relax % LaTeX2.09 is used\r
+\else% LaTeX2e is used, so set ll to true\r
+\global\@lltrue\r
+\fi\r
+\r
+\if@ll\r
+  \NeedsTeXFormat{LaTeX2e}\r
+  \ProvidesClass{sig-alternate} [2007/06/07 - V2.3 - based on acmproc.cls V1.3 <Nov. 30 '99>]\r
+  \RequirePackage{latexsym}% QUERY: are these two really needed?\r
+  \let\dooptions\ProcessOptions\r
+\else\r
+  \let\dooptions\@options\r
+\fi\r
+%% END CHANGES\r
+\r
+\def\@height{height}\r
+\def\@width{width}\r
+\def\@minus{minus}\r
+\def\@plus{plus}\r
+\def\hb@xt@{\hbox to}\r
+\newif\if@faircopy\r
+\@faircopyfalse\r
+\def\ds@faircopy{\@faircopytrue}\r
+\r
+\def\ds@preprint{\@faircopyfalse}\r
+\r
+\@twosidetrue\r
+\@mparswitchtrue\r
+\def\ds@draft{\overfullrule 5\p@}\r
+%% CHANGE ON NEXT LINE\r
+\dooptions\r
+\r
+\lineskip \p@\r
+\normallineskip \p@\r
+\def\baselinestretch{1}\r
+\def\@ptsize{0} %needed for amssymbols.sty\r
+\r
+%% CHANGES ON NEXT LINES\r
+\if@ll% allow use of old-style font change commands in LaTeX2e\r
+\@maxdepth\maxdepth\r
+%\r
+\DeclareOldFontCommand{\rm}{\ninept\rmfamily}{\mathrm}\r
+\DeclareOldFontCommand{\sf}{\normalfont\sffamily}{\mathsf}\r
+\DeclareOldFontCommand{\tt}{\normalfont\ttfamily}{\mathtt}\r
+\DeclareOldFontCommand{\bf}{\normalfont\bfseries}{\mathbf}\r
+\DeclareOldFontCommand{\it}{\normalfont\itshape}{\mathit}\r
+\DeclareOldFontCommand{\sl}{\normalfont\slshape}{\@nomath\sl}\r
+\DeclareOldFontCommand{\sc}{\normalfont\scshape}{\@nomath\sc}\r
+\DeclareRobustCommand*{\cal}{\@fontswitch{\relax}{\mathcal}}\r
+\DeclareRobustCommand*{\mit}{\@fontswitch{\relax}{\mathnormal}}\r
+\fi\r
+%\r
+\if@ll\r
+ \renewcommand{\rmdefault}{cmr}  % was 'ttm'\r
+% Note! I have also found 'mvr' to work ESPECIALLY well.\r
+% Gerry - October 1999\r
+% You may need to change your LV1times.fd file so that sc is\r
+% mapped to cmcsc - -for smallcaps -- that is if you decide\r
+% to change {cmr} to {times} above. (Not recommended)\r
+  \renewcommand{\@ptsize}{}\r
+  \renewcommand{\normalsize}{%\r
+    \@setfontsize\normalsize\@ixpt{10.5\p@}%\ninept%\r
+    \abovedisplayskip 6\p@ \@plus2\p@ \@minus\p@\r
+    \belowdisplayskip \abovedisplayskip\r
+    \abovedisplayshortskip 6\p@ \@minus 3\p@\r
+    \belowdisplayshortskip 6\p@ \@minus 3\p@\r
+    \let\@listi\@listI\r
+  }\r
+\else\r
+  \def\@normalsize{%changed next to 9 from 10\r
+    \@setsize\normalsize{9\p@}\ixpt\@ixpt\r
+   \abovedisplayskip 6\p@ \@plus2\p@ \@minus\p@\r
+    \belowdisplayskip \abovedisplayskip\r
+    \abovedisplayshortskip 6\p@ \@minus 3\p@\r
+    \belowdisplayshortskip 6\p@ \@minus 3\p@\r
+    \let\@listi\@listI\r
+  }%\r
+\fi\r
+\if@ll\r
+  \newcommand\scriptsize{\@setfontsize\scriptsize\@viipt{8\p@}}\r
+  \newcommand\tiny{\@setfontsize\tiny\@vpt{6\p@}}\r
+  \newcommand\large{\@setfontsize\large\@xiipt{14\p@}}\r
+  \newcommand\Large{\@setfontsize\Large\@xivpt{18\p@}}\r
+  \newcommand\LARGE{\@setfontsize\LARGE\@xviipt{20\p@}}\r
+  \newcommand\huge{\@setfontsize\huge\@xxpt{25\p@}}\r
+  \newcommand\Huge{\@setfontsize\Huge\@xxvpt{30\p@}}\r
+\else\r
+  \def\scriptsize{\@setsize\scriptsize{8\p@}\viipt\@viipt}\r
+  \def\tiny{\@setsize\tiny{6\p@}\vpt\@vpt}\r
+  \def\large{\@setsize\large{14\p@}\xiipt\@xiipt}\r
+  \def\Large{\@setsize\Large{18\p@}\xivpt\@xivpt}\r
+  \def\LARGE{\@setsize\LARGE{20\p@}\xviipt\@xviipt}\r
+  \def\huge{\@setsize\huge{25\p@}\xxpt\@xxpt}\r
+  \def\Huge{\@setsize\Huge{30\p@}\xxvpt\@xxvpt}\r
+\fi\r
+\normalsize\r
+\r
+% make aubox hsize/number of authors up to 3, less gutter\r
+% then showbox gutter showbox gutter showbox -- GKMT Aug 99\r
+\newbox\@acmtitlebox\r
+\def\@maketitle{\newpage\r
+ \null\r
+ \setbox\@acmtitlebox\vbox{%\r
+\baselineskip 20pt\r
+\vskip 2em                   % Vertical space above title.\r
+   \begin{center}\r
+    {\ttlfnt \@title\par}       % Title set in 18pt Helvetica (Arial) bold size.\r
+    \vskip 1.5em                % Vertical space after title.\r
+%This should be the subtitle.\r
+{\subttlfnt \the\subtitletext\par}\vskip 1.25em%\fi\r
+    {\baselineskip 16pt\aufnt   % each author set in \12 pt Arial, in a\r
+     \lineskip .5em             % tabular environment\r
+     \begin{tabular}[t]{c}\@author\r
+     \end{tabular}\par}\r
+    \vskip 1.5em               % Vertical space after author.\r
+   \end{center}}\r
+ \dimen0=\ht\@acmtitlebox\r
+ \advance\dimen0 by -12.75pc\relax % Increased space for title box -- KBT\r
+ \unvbox\@acmtitlebox\r
+ \ifdim\dimen0<0.0pt\relax\vskip-\dimen0\fi}\r
+\r
+\r
+\newcount\titlenotecount\r
+\global\titlenotecount=0\r
+\newtoks\tntoks\r
+\newtoks\tntokstwo\r
+\newtoks\tntoksthree\r
+\newtoks\tntoksfour\r
+\newtoks\tntoksfive\r
+\r
+\def\abstract{\r
+\ifnum\titlenotecount>0 % was =1\r
+    \insert\footins{%\r
+    \reset@font\footnotesize\r
+        \interlinepenalty\interfootnotelinepenalty\r
+        \splittopskip\footnotesep\r
+        \splitmaxdepth \dp\strutbox \floatingpenalty \@MM\r
+        \hsize\columnwidth \@parboxrestore\r
+        \protected@edef\@currentlabel{%\r
+        }%\r
+        \color@begingroup\r
+\ifnum\titlenotecount=1\r
+      \@maketntext{%\r
+         \raisebox{4pt}{$\ast$}\rule\z@\footnotesep\ignorespaces\the\tntoks\@finalstrut\strutbox}%\r
+\fi\r
+\ifnum\titlenotecount=2\r
+      \@maketntext{%\r
+      \raisebox{4pt}{$\ast$}\rule\z@\footnotesep\ignorespaces\the\tntoks\par\@finalstrut\strutbox}%\r
+\@maketntext{%\r
+         \raisebox{4pt}{$\dagger$}\rule\z@\footnotesep\ignorespaces\the\tntokstwo\@finalstrut\strutbox}%\r
+\fi\r
+\ifnum\titlenotecount=3\r
+      \@maketntext{%\r
+         \raisebox{4pt}{$\ast$}\rule\z@\footnotesep\ignorespaces\the\tntoks\par\@finalstrut\strutbox}%\r
+\@maketntext{%\r
+         \raisebox{4pt}{$\dagger$}\rule\z@\footnotesep\ignorespaces\the\tntokstwo\par\@finalstrut\strutbox}%\r
+\@maketntext{%\r
+         \raisebox{4pt}{$\ddagger$}\rule\z@\footnotesep\ignorespaces\the\tntoksthree\@finalstrut\strutbox}%\r
+\fi\r
+\ifnum\titlenotecount=4\r
+      \@maketntext{%\r
+         \raisebox{4pt}{$\ast$}\rule\z@\footnotesep\ignorespaces\the\tntoks\par\@finalstrut\strutbox}%\r
+\@maketntext{%\r
+         \raisebox{4pt}{$\dagger$}\rule\z@\footnotesep\ignorespaces\the\tntokstwo\par\@finalstrut\strutbox}%\r
+\@maketntext{%\r
+         \raisebox{4pt}{$\ddagger$}\rule\z@\footnotesep\ignorespaces\the\tntoksthree\par\@finalstrut\strutbox}%\r
+\@maketntext{%\r
+         \raisebox{4pt}{$\S$}\rule\z@\footnotesep\ignorespaces\the\tntoksfour\@finalstrut\strutbox}%\r
+\fi\r
+\ifnum\titlenotecount=5\r
+      \@maketntext{%\r
+         \raisebox{4pt}{$\ast$}\rule\z@\footnotesep\ignorespaces\the\tntoks\par\@finalstrut\strutbox}%\r
+\@maketntext{%\r
+         \raisebox{4pt}{$\dagger$}\rule\z@\footnotesep\ignorespaces\the\tntokstwo\par\@finalstrut\strutbox}%\r
+\@maketntext{%\r
+         \raisebox{4pt}{$\ddagger$}\rule\z@\footnotesep\ignorespaces\the\tntoksthree\par\@finalstrut\strutbox}%\r
+\@maketntext{%\r
+         \raisebox{4pt}{$\S$}\rule\z@\footnotesep\ignorespaces\the\tntoksfour\par\@finalstrut\strutbox}%\r
+\@maketntext{%\r
+         \raisebox{4pt}{$\P$}\rule\z@\footnotesep\ignorespaces\the\tntoksfive\@finalstrut\strutbox}%\r
+\fi\r
+   \color@endgroup} %g}\r
+\fi\r
+\setcounter{footnote}{0}\r
+\section*{ABSTRACT}\normalsize%\ninept\r
+}\r
+\r
+\def\endabstract{\if@twocolumn\else\endquotation\fi}\r
+\r
+\def\keywords{\if@twocolumn\r
+\section*{Keywords}\r
+\else \small\r
+\quotation\r
+\fi}\r
+\r
+\def\terms{\if@twocolumn\r
+\section*{General Terms}\r
+\else \small\r
+\quotation\r
+\fi}\r
+\r
+% -- Classification needs to be a bit smart due to optionals - Gerry/Georgia November 2nd. 1999\r
+\newcount\catcount\r
+\global\catcount=1\r
+\r
+\def\category#1#2#3{%\r
+\ifnum\catcount=1\r
+\section*{Categories and Subject Descriptors}\r
+\advance\catcount by 1\else{\unskip; }\fi\r
+    \@ifnextchar [{\@category{#1}{#2}{#3}}{\@category{#1}{#2}{#3}[]}%\r
+}\r
+\r
+\def\@category#1#2#3[#4]{%\r
+    \begingroup\r
+        \let\and\relax\r
+            #1 [\textbf{#2}]%\r
+            \if!#4!%\r
+                \if!#3!\else : #3\fi\r
+            \else\r
+                :\space\r
+                \if!#3!\else #3\kern\z@---\hskip\z@\fi\r
+                \textit{#4}%\r
+            \fi\r
+    \endgroup\r
+}\r
+%\r
+\r
+%%% This section (written by KBT) handles the 1" box in the lower left\r
+%%% corner of the left column of the first page by creating a picture,\r
+%%% and inserting the predefined string at the bottom (with a negative\r
+%%% displacement to offset the space allocated for a non-existent\r
+%%% caption).\r
+%%%\r
+\newtoks\copyrightnotice\r
+\def\ftype@copyrightbox{8}\r
+\def\@copyrightspace{\r
+\@float{copyrightbox}[b]\r
+\begin{center}\r
+\setlength{\unitlength}{1pc}\r
+\begin{picture}(20,6) %Space for copyright notice\r
+\put(0,-0.95){\crnotice{\@toappear}}\r
+\end{picture}\r
+\end{center}\r
+\end@float}\r
+\r
+\def\@toappear{} % Default setting blank - commands below change this.\r
+\long\def\toappear#1{\def\@toappear{\parbox[b]{20pc}{\baselineskip 9pt#1}}}\r
+\def\toappearbox#1{\def\@toappear{\raisebox{5pt}{\framebox[20pc]{\parbox[b]{19pc}{#1}}}}}\r
+\r
+\newtoks\conf\r
+\newtoks\confinfo\r
+\def\conferenceinfo#1#2{\global\conf={#1}\global\confinfo{#2}}\r
+\r
+\r
+\def\marginpar{\@latexerr{The \marginpar command is not allowed in the\r
+  `acmconf' document style.}\@eha}\r
+\r
+\mark{{}{}}     % Initializes TeX's marks\r
+\r
+\def\today{\ifcase\month\or\r
+  January\or February\or March\or April\or May\or June\or\r
+  July\or August\or September\or October\or November\or December\fi\r
+  \space\number\day, \number\year}\r
+\r
+\def\@begintheorem#1#2{%\r
+    \parskip 0pt % GM July 2000 (for tighter spacing)\r
+    \trivlist\r
+    \item[%\r
+        \hskip 10\p@\r
+        \hskip \labelsep\r
+        {{\sc #1}\hskip 5\p@\relax#2.}%\r
+    ]\r
+    \it\r
+}\r
+\def\@opargbegintheorem#1#2#3{%\r
+    \parskip 0pt % GM July 2000 (for tighter spacing)\r
+    \trivlist\r
+    \item[%\r
+        \hskip 10\p@\r
+        \hskip \labelsep\r
+        {\sc #1\ #2\             % This mod by Gerry to enumerate corollaries\r
+   \setbox\@tempboxa\hbox{(#3)}  % and bracket the 'corollary title'\r
+        \ifdim \wd\@tempboxa>\z@ % and retain the correct numbering of e.g. theorems\r
+            \hskip 5\p@\relax    % if they occur 'around' said corollaries.\r
+            \box\@tempboxa       % Gerry - Nov. 1999.\r
+        \fi.}%\r
+    ]\r
+    \it\r
+}\r
+\newif\if@qeded\r
+\global\@qededfalse\r
+\r
+% -- original\r
+%\def\proof{%\r
+%  \vspace{-\parskip} % GM July 2000 (for tighter spacing)\r
+%    \global\@qededfalse\r
+%    \@ifnextchar[{\@xproof}{\@proof}%\r
+%}\r
+% -- end of original\r
+\r
+% (JSS) Fix for vertical spacing bug - Gerry Murray July 30th. 2002\r
+\def\proof{%\r
+\vspace{-\lastskip}\vspace{-\parsep}\penalty-51%\r
+\global\@qededfalse\r
+\@ifnextchar[{\@xproof}{\@proof}%\r
+}\r
+\r
+\def\endproof{%\r
+    \if@qeded\else\qed\fi\r
+    \endtrivlist\r
+}\r
+\def\@proof{%\r
+    \trivlist\r
+    \item[%\r
+        \hskip 10\p@\r
+        \hskip \labelsep\r
+        {\sc Proof.}%\r
+    ]\r
+    \ignorespaces\r
+}\r
+\def\@xproof[#1]{%\r
+    \trivlist\r
+    \item[\hskip 10\p@\hskip \labelsep{\sc Proof #1.}]%\r
+    \ignorespaces\r
+}\r
+\def\qed{%\r
+    \unskip\r
+    \kern 10\p@\r
+    \begingroup\r
+        \unitlength\p@\r
+        \linethickness{.4\p@}%\r
+        \framebox(6,6){}%\r
+    \endgroup\r
+    \global\@qededtrue\r
+}\r
+\r
+\def\newdef#1#2{%\r
+    \expandafter\@ifdefinable\csname #1\endcsname\r
+        {\@definecounter{#1}%\r
+         \expandafter\xdef\csname the#1\endcsname{\@thmcounter{#1}}%\r
+         \global\@namedef{#1}{\@defthm{#1}{#2}}%\r
+         \global\@namedef{end#1}{\@endtheorem}%\r
+    }%\r
+}\r
+\def\@defthm#1#2{%\r
+    \refstepcounter{#1}%\r
+    \@ifnextchar[{\@ydefthm{#1}{#2}}{\@xdefthm{#1}{#2}}%\r
+}\r
+\def\@xdefthm#1#2{%\r
+    \@begindef{#2}{\csname the#1\endcsname}%\r
+    \ignorespaces\r
+}\r
+\def\@ydefthm#1#2[#3]{%\r
+    \trivlist\r
+    \item[%\r
+        \hskip 10\p@\r
+        \hskip \labelsep\r
+        {\it #2%\r
+         \savebox\@tempboxa{#3}%\r
+         \ifdim \wd\@tempboxa>\z@\r
+            \ \box\@tempboxa\r
+         \fi.%\r
+        }]%\r
+    \ignorespaces\r
+}\r
+\def\@begindef#1#2{%\r
+    \trivlist\r
+    \item[%\r
+        \hskip 10\p@\r
+        \hskip \labelsep\r
+        {\it #1\ \rm #2.}%\r
+    ]%\r
+}\r
+\def\theequation{\arabic{equation}}\r
+\r
+\newcounter{part}\r
+\newcounter{section}\r
+\newcounter{subsection}[section]\r
+\newcounter{subsubsection}[subsection]\r
+\newcounter{paragraph}[subsubsection]\r
+\def\thepart{\Roman{part}}\r
+\def\thesection{\arabic{section}}\r
+\def\thesubsection{\thesection.\arabic{subsection}}\r
+\def\thesubsubsection{\thesubsection.\arabic{subsubsection}} %removed \subsecfnt 29 July 2002 gkmt\r
+\def\theparagraph{\thesubsubsection.\arabic{paragraph}} %removed \subsecfnt 29 July 2002 gkmt\r
+\newif\if@uchead\r
+\@ucheadfalse\r
+\r
+%% CHANGES: NEW NOTE\r
+%% NOTE: OK to use old-style font commands below, since they were\r
+%% suitably redefined for LaTeX2e\r
+%% END CHANGES\r
+\setcounter{secnumdepth}{3}\r
+\def\part{%\r
+    \@startsection{part}{9}{\z@}{-10\p@ \@plus -4\p@ \@minus -2\p@}\r
+        {4\p@}{\normalsize\@ucheadtrue}%\r
+}\r
+\def\section{%\r
+    \@startsection{section}{1}{\z@}{-10\p@ \@plus -4\p@ \@minus -2\p@}% GM\r
+    {4\p@}{\baselineskip 14pt\secfnt\@ucheadtrue}%\r
+}\r
+\r
+\def\subsection{%\r
+    \@startsection{subsection}{2}{\z@}{-8\p@ \@plus -2\p@ \@minus -\p@}\r
+    {4\p@}{\secfnt}%\r
+}\r
+\def\subsubsection{%\r
+    \@startsection{subsubsection}{3}{\z@}{-8\p@ \@plus -2\p@ \@minus -\p@}%\r
+    {4\p@}{\subsecfnt}%\r
+}\r
+%\def\paragraph{%\r
+%    \vskip 12pt\@startsection{paragraph}{3}{\z@}{6\p@ \@plus \p@}% original\r
+%    {-5\p@}{\subsecfnt}%\r
+%}\r
+%  If one wants sections, subsections and subsubsections numbered,\r
+%  but not paragraphs, one usually sets secnumepth to 3.\r
+%  For that, the "depth" of paragraphs must be given correctly\r
+%  in the definition (``4'' instead of ``3'' as second argument\r
+%  of @startsection):\r
+\def\paragraph{%\r
+    \vskip 12pt\@startsection{paragraph}{4}{\z@}{6\p@ \@plus \p@}%    % GM and Wolfgang May - 11/30/06\r
+    {-5\p@}{\subsecfnt}%\r
+}\r
+\let\@period=.\r
+\def\@startsection#1#2#3#4#5#6{%\r
+        \if@noskipsec  %gkmt, 11 aug 99\r
+        \global\let\@period\@empty\r
+        \leavevmode\r
+        \global\let\@period.%\r
+    \fi\r
+      \par %\r
+    \@tempskipa #4\relax\r
+    \@afterindenttrue\r
+    \ifdim \@tempskipa <\z@\r
+        \@tempskipa -\@tempskipa\r
+        \@afterindentfalse\r
+    \fi\r
+    \if@nobreak\r
+    \everypar{}%\r
+    \else\r
+        \addpenalty\@secpenalty\r
+        \addvspace\@tempskipa\r
+    \fi\r
+\parskip=0pt % GM July 2000 (non numbered) section heads\r
+    \@ifstar\r
+        {\@ssect{#3}{#4}{#5}{#6}}\r
+        {\@dblarg{\@sect{#1}{#2}{#3}{#4}{#5}{#6}}}%\r
+}\r
+\def\@sect#1#2#3#4#5#6[#7]#8{%\r
+    \ifnum #2>\c@secnumdepth\r
+        \let\@svsec\@empty\r
+    \else\r
+        \refstepcounter{#1}%\r
+        \edef\@svsec{%\r
+            \begingroup\r
+                %\ifnum#2>2 \noexpand\rm \fi % changed to next 29 July 2002 gkmt\r
+            \ifnum#2>2 \noexpand#6 \fi\r
+                \csname the#1\endcsname\r
+            \endgroup\r
+            \ifnum #2=1\relax .\fi\r
+            \hskip 1em\r
+        }%\r
+    \fi\r
+    \@tempskipa #5\relax\r
+    \ifdim \@tempskipa>\z@\r
+        \begingroup\r
+            #6\relax\r
+            \@hangfrom{\hskip #3\relax\@svsec}%\r
+            \begingroup\r
+                \interlinepenalty \@M\r
+                \if@uchead\r
+                    \uppercase{#8}%\r
+                \else\r
+                    #8%\r
+                \fi\r
+                \par\r
+            \endgroup\r
+        \endgroup\r
+        \csname #1mark\endcsname{#7}%\r
+        \vskip -12pt  %gkmt, 11 aug 99 and GM July 2000 (was -14) - numbered section head spacing\r
+\addcontentsline{toc}{#1}{%\r
+            \ifnum #2>\c@secnumdepth \else\r
+                \protect\numberline{\csname the#1\endcsname}%\r
+            \fi\r
+            #7%\r
+        }%\r
+    \else\r
+        \def\@svsechd{%\r
+            #6%\r
+            \hskip #3\relax\r
+            \@svsec\r
+            \if@uchead\r
+                \uppercase{#8}%\r
+            \else\r
+                #8%\r
+            \fi\r
+            \csname #1mark\endcsname{#7}%\r
+            \addcontentsline{toc}{#1}{%\r
+                \ifnum #2>\c@secnumdepth \else\r
+                    \protect\numberline{\csname the#1\endcsname}%\r
+                \fi\r
+                #7%\r
+            }%\r
+        }%\r
+    \fi\r
+    \@xsect{#5}\hskip 1pt\r
+    \par\r
+}\r
+\def\@xsect#1{%\r
+    \@tempskipa #1\relax\r
+    \ifdim \@tempskipa>\z@\r
+        \par\r
+        \nobreak\r
+        \vskip \@tempskipa\r
+        \@afterheading\r
+    \else\r
+        \global\@nobreakfalse\r
+        \global\@noskipsectrue\r
+        \everypar{%\r
+            \if@noskipsec\r
+                \global\@noskipsecfalse\r
+                \clubpenalty\@M\r
+                \hskip -\parindent\r
+                \begingroup\r
+                    \@svsechd\r
+                    \@period\r
+                \endgroup\r
+                \unskip\r
+                \@tempskipa #1\relax\r
+                \hskip -\@tempskipa\r
+            \else\r
+                \clubpenalty \@clubpenalty\r
+                \everypar{}%\r
+            \fi\r
+        }%\r
+    \fi\r
+    \ignorespaces\r
+}\r
+\def\@trivlist{%\r
+    \@topsepadd\topsep\r
+    \if@noskipsec\r
+        \global\let\@period\@empty\r
+        \leavevmode\r
+        \global\let\@period.%\r
+    \fi\r
+    \ifvmode\r
+        \advance\@topsepadd\partopsep\r
+    \else\r
+        \unskip\r
+        \par\r
+    \fi\r
+    \if@inlabel\r
+        \@noparitemtrue\r
+        \@noparlisttrue\r
+    \else\r
+        \@noparlistfalse\r
+        \@topsep\@topsepadd\r
+    \fi\r
+    \advance\@topsep \parskip\r
+    \leftskip\z@skip\r
+    \rightskip\@rightskip\r
+    \parfillskip\@flushglue\r
+    \@setpar{\if@newlist\else{\@@par}\fi}\r
+    \global\@newlisttrue\r
+    \@outerparskip\parskip\r
+}\r
+\r
+%%% Actually, 'abbrev' works just fine as the default\r
+%%% Bibliography style.\r
+\r
+\typeout{Using 'Abbrev' bibliography style}\r
+\newcommand\bibyear[2]{%\r
+    \unskip\quad\ignorespaces#1\unskip\r
+    \if#2..\quad \else \quad#2 \fi\r
+}\r
+\newcommand{\bibemph}[1]{{\em#1}}\r
+\newcommand{\bibemphic}[1]{{\em#1\/}}\r
+\newcommand{\bibsc}[1]{{\sc#1}}\r
+\def\@normalcite{%\r
+    \def\@cite##1##2{[##1\if@tempswa , ##2\fi]}%\r
+}\r
+\def\@citeNB{%\r
+    \def\@cite##1##2{##1\if@tempswa , ##2\fi}%\r
+}\r
+\def\@citeRB{%\r
+    \def\@cite##1##2{##1\if@tempswa , ##2\fi]}%\r
+}\r
+\def\start@cite#1#2{%\r
+    \edef\citeauthoryear##1##2##3{%\r
+        ###1%\r
+        \ifnum#2=\z@ \else\ ###2\fi\r
+    }%\r
+    \ifnum#1=\thr@@\r
+        \let\@@cite\@citeyear\r
+    \else\r
+        \let\@@cite\@citenormal\r
+    \fi\r
+    \@ifstar{\@citeNB\@@cite}{\@normalcite\@@cite}%\r
+}\r
+\def\cite{\start@cite23}\r
+\def\citeNP{\cite*}\r
+\def\citeA{\start@cite10}\r
+\def\citeANP{\citeA*}\r
+\def\shortcite{\start@cite23}\r
+\def\shortciteNP{\shortcite*}\r
+\def\shortciteA{\start@cite20}\r
+\def\shortciteANP{\shortciteA*}\r
+\def\citeyear{\start@cite30}\r
+\def\citeyearNP{\citeyear*}\r
+\def\citeN{%\r
+    \@citeRB\r
+    \def\citeauthoryear##1##2##3{##1\ [##3%\r
+        \def\reserved@a{##1}%\r
+        \def\citeauthoryear####1####2####3{%\r
+            \def\reserved@b{####1}%\r
+            \ifx\reserved@a\reserved@b\r
+                ####3%\r
+            \else\r
+                \errmessage{Package acmart Error: author mismatch\r
+                         in \string\citeN^^J^^J%\r
+                    See the acmart package documentation for explanation}%\r
+            \fi\r
+        }%\r
+    }%\r
+    \@ifstar\@citeyear\@citeyear\r
+}\r
+\def\shortciteN{%\r
+    \@citeRB\r
+    \def\citeauthoryear##1##2##3{##2\ [##3%\r
+        \def\reserved@a{##2}%\r
+        \def\citeauthoryear####1####2####3{%\r
+            \def\reserved@b{####2}%\r
+            \ifx\reserved@a\reserved@b\r
+                ####3%\r
+            \else\r
+                \errmessage{Package acmart Error: author mismatch\r
+                         in \string\shortciteN^^J^^J%\r
+                    See the acmart package documentation for explanation}%\r
+            \fi\r
+        }%\r
+    }%\r
+    \@ifstar\@citeyear\@citeyear  % GM July 2000\r
+}\r
+\def\@citenormal{%\r
+    \@ifnextchar [{\@tempswatrue\@citex;}\r
+                  {\@tempswafalse\@citex,[]}% % GM July 2000\r
+}\r
+\def\@citeyear{%\r
+    \@ifnextchar [{\@tempswatrue\@citex,}%\r
+                  {\@tempswafalse\@citex,[]}%\r
+}\r
+\def\@citex#1[#2]#3{%\r
+    \let\@citea\@empty\r
+    \@cite{%\r
+        \@for\@citeb:=#3\do{%\r
+            \@citea\r
+            \def\@citea{#1 }%\r
+            \edef\@citeb{\expandafter\@iden\@citeb}%\r
+            \if@filesw\r
+                \immediate\write\@auxout{\string\citation{\@citeb}}%\r
+            \fi\r
+            \@ifundefined{b@\@citeb}{%\r
+                {\bf ?}%\r
+                \@warning{%\r
+                    Citation `\@citeb' on page \thepage\space undefined%\r
+                }%\r
+            }%\r
+            {\csname b@\@citeb\endcsname}%\r
+        }%\r
+    }{#2}%\r
+}\r
+\let\@biblabel\@gobble\r
+\newdimen\bibindent\r
+\setcounter{enumi}{1}\r
+\bibindent=0em\r
+\def\thebibliography#1{% \r
+\ifnum\addauflag=0\addauthorsection\global\addauflag=1\fi\r
+     \section[References]{%    <=== OPTIONAL ARGUMENT ADDED HERE\r
+        {References} % was uppercased but this affects pdf bookmarks (SP/GM October 2004)\r
+          {\vskip -9pt plus 1pt} % GM Nov. 2006 / GM July 2000 (for somewhat tighter spacing) \r
+         \@mkboth{{\refname}}{{\refname}}%\r
+     }%\r
+     \list{[\arabic{enumi}]}{%\r
+         \settowidth\labelwidth{[#1]}%\r
+         \leftmargin\labelwidth\r
+         \advance\leftmargin\labelsep\r
+         \advance\leftmargin\bibindent\r
+         \parsep=0pt\itemsep=1pt % GM July 2000\r
+         \itemindent -\bibindent\r
+         \listparindent \itemindent\r
+         \usecounter{enumi}\r
+     }%\r
+     \let\newblock\@empty\r
+     \raggedright % GM July 2000\r
+     \sloppy\r
+     \sfcode`\.=1000\relax\r
+}\r
+\r
+\r
+\gdef\balancecolumns\r
+{\vfill\eject\r
+\global\@colht=\textheight\r
+\global\ht\@cclv=\textheight\r
+}\r
+\r
+\newcount\colcntr\r
+\global\colcntr=0\r
+\newbox\savebox\r
+\r
+\gdef \@makecol {%\r
+\global\advance\colcntr by 1\r
+\ifnum\colcntr>2 \global\colcntr=1\fi\r
+   \ifvoid\footins\r
+     \setbox\@outputbox \box\@cclv\r
+   \else\r
+     \setbox\@outputbox \vbox{%\r
+\boxmaxdepth \@maxdepth\r
+       \@tempdima\dp\@cclv\r
+       \unvbox \@cclv\r
+       \vskip-\@tempdima\r
+       \vskip \skip\footins\r
+       \color@begingroup\r
+         \normalcolor\r
+         \footnoterule\r
+         \unvbox \footins\r
+       \color@endgroup\r
+       }%\r
+   \fi\r
+   \xdef\@freelist{\@freelist\@midlist}%\r
+   \global \let \@midlist \@empty\r
+   \@combinefloats\r
+   \ifvbox\@kludgeins\r
+     \@makespecialcolbox\r
+   \else\r
+     \setbox\@outputbox \vbox to\@colht {%\r
+\@texttop\r
+       \dimen@ \dp\@outputbox\r
+       \unvbox \@outputbox\r
+   \vskip -\dimen@\r
+       \@textbottom\r
+       }%\r
+   \fi\r
+   \global \maxdepth \@maxdepth\r
+}\r
+\def\titlenote{\@ifnextchar[\@xtitlenote{\stepcounter\@mpfn\r
+\global\advance\titlenotecount by 1\r
+\ifnum\titlenotecount=1\r
+    \raisebox{9pt}{$\ast$}\r
+\fi\r
+\ifnum\titlenotecount=2\r
+    \raisebox{9pt}{$\dagger$}\r
+\fi\r
+\ifnum\titlenotecount=3\r
+    \raisebox{9pt}{$\ddagger$}\r
+\fi\r
+\ifnum\titlenotecount=4\r
+\raisebox{9pt}{$\S$}\r
+\fi\r
+\ifnum\titlenotecount=5\r
+\raisebox{9pt}{$\P$}\r
+\fi\r
+         \@titlenotetext\r
+}}\r
+\r
+\long\def\@titlenotetext#1{\insert\footins{%\r
+\ifnum\titlenotecount=1\global\tntoks={#1}\fi\r
+\ifnum\titlenotecount=2\global\tntokstwo={#1}\fi\r
+\ifnum\titlenotecount=3\global\tntoksthree={#1}\fi\r
+\ifnum\titlenotecount=4\global\tntoksfour={#1}\fi\r
+\ifnum\titlenotecount=5\global\tntoksfive={#1}\fi\r
+    \reset@font\footnotesize\r
+    \interlinepenalty\interfootnotelinepenalty\r
+    \splittopskip\footnotesep\r
+    \splitmaxdepth \dp\strutbox \floatingpenalty \@MM\r
+    \hsize\columnwidth \@parboxrestore\r
+    \protected@edef\@currentlabel{%\r
+    }%\r
+    \color@begingroup\r
+   \color@endgroup}}\r
+\r
+%%%%%%%%%%%%%%%%%%%%%%%%%\r
+\ps@plain\r
+\baselineskip=11pt\r
+\let\thepage\relax % For NO page numbers - GM Nov. 30th. 1999 and July 2000\r
+\def\setpagenumber#1{\global\setcounter{page}{#1}}\r
+%\pagenumbering{arabic}  % Arabic page numbers GM July 2000\r
+\twocolumn             % Double column.\r
+\flushbottom           % Even bottom -- alas, does not balance columns at end of document\r
+\pagestyle{plain}\r
+\r
+% Need Copyright Year and Copyright Data to be user definable (in .tex file).\r
+% Gerry Nov. 30th. 1999\r
+\newtoks\copyrtyr\r
+\newtoks\acmcopyr\r
+\newtoks\boilerplate\r
+\global\acmcopyr={X-XXXXX-XX-X/XX/XX}  % Default - 5/11/2001 *** Gerry\r
+\global\copyrtyr={200X}                % Default - 3/3/2003 *** Gerry\r
+\def\CopyrightYear#1{\global\copyrtyr{#1}}\r
+\def\crdata#1{\global\acmcopyr{#1}}\r
+\def\permission#1{\global\boilerplate{#1}}\r
+%\r
+\global\boilerplate={Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page.  To copy otherwise, to republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee.}\r
+\newtoks\copyrightetc\r
+\global\copyrightetc{Copyright \the\copyrtyr\ ACM \the\acmcopyr\ ...\$5.00}\r
+\toappear{\the\boilerplate\par\r
+{\confname{\the\conf}} \the\confinfo\par \the\copyrightetc.}\r
+%\DeclareFixedFont{\altcrnotice}{OT1}{tmr}{m}{n}{8}  % << patch needed for accenting e.g. Montreal - Gerry, May 2007\r
+%\DeclareFixedFont{\altconfname}{OT1}{tmr}{m}{it}{8}  % << patch needed for accenting in italicized confname - Gerry, May 2007\r
+%\r
+%{\altconfname{{\the\conf}}} {\altcrnotice\the\confinfo\par} \the\copyrightetc.}  % << Gerry, May 2007\r
+%\r
+% The following section (i.e. 3 .sty inclusions) was added in May 2007 so as to fix the problems that many\r
+% authors were having with accents. Sometimes accents would occur, but the letter-character would be of a different\r
+% font. Conversely the letter-character font would be correct but, e.g. a 'bar' would appear superimposed on the\r
+% character instead of, say, an unlaut/diaresis. Sometimes the letter-character would NOT appear at all.\r
+% Using [T1]{fontenc} outright was not an option as this caused 99% of the authors to 'produce' a Type-3 (bitmapped)\r
+% PDF file - useless for production. \r
+%\r
+% For proper (font) accenting we NEED these packages to be part of the .cls file i.e. 'ae', 'aecompl' and 'aeguil' \r
+% ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\r
+%% This is file `ae.sty' \r
+\def\fileversion{1.3}\r
+\def\filedate{2001/02/12}\r
+\NeedsTeXFormat{LaTeX2e}\r
+%\ProvidesPackage{ae}[\filedate\space\fileversion\space  % GM\r
+% Almost European Computer Modern]                       % GM - keeping the log file clean(er)\r
+\newif\if@ae@slides \@ae@slidesfalse\r
+\DeclareOption{slides}{\@ae@slidestrue}\r
+\ProcessOptions\r
+\fontfamily{aer}\r
+\RequirePackage[T1]{fontenc}\r
+\if@ae@slides\r
+    \renewcommand{\sfdefault}{laess}\r
+    \renewcommand{\rmdefault}{laess} % no roman\r
+    \renewcommand{\ttdefault}{laett}\r
+\else\r
+    \renewcommand{\sfdefault}{aess}\r
+    \renewcommand{\rmdefault}{aer}\r
+    \renewcommand{\ttdefault}{aett}\r
+\fi\r
+\endinput\r
+%% \r
+%% End of file `ae.sty'.\r
+%\r
+%\r
+\def\fileversion{0.9}\r
+\def\filedate{1998/07/23}\r
+\NeedsTeXFormat{LaTeX2e}\r
+%\ProvidesPackage{aecompl}[\filedate\space\fileversion\space   % GM\r
+%T1 Complements for AE fonts (D. Roegel)]                      % GM -- keeping the log file clean(er)\r
+ \r
+\def\@ae@compl#1{{\fontencoding{T1}\fontfamily{cmr}\selectfont\symbol{#1}}}\r
+\def\guillemotleft{\@ae@compl{19}}\r
+\def\guillemotright{\@ae@compl{20}}\r
+\def\guilsinglleft{\@ae@compl{14}}\r
+\def\guilsinglright{\@ae@compl{15}}\r
+\def\TH{\@ae@compl{222}}\r
+\def\NG{\@ae@compl{141}}\r
+\def\ng{\@ae@compl{173}}\r
+\def\th{\@ae@compl{254}}\r
+\def\DJ{\@ae@compl{208}}\r
+\def\dj{\@ae@compl{158}}\r
+\def\DH{\@ae@compl{208}}\r
+\def\dh{\@ae@compl{240}}\r
+\def\@perthousandzero{\@ae@compl{24}}\r
+\def\textperthousand{\%\@perthousandzero}\r
+\def\textpertenthousand{\%\@perthousandzero\@perthousandzero}\r
+\endinput\r
+%\r
+%\r
+%% This is file `aeguill.sty' \r
+% This file gives french guillemets (and not guillemots!)\r
+% built with the Polish CMR fonts (default), WNCYR fonts, the LASY fonts \r
+% or with the EC fonts. \r
+% This is useful in conjunction with the ae package\r
+% (this package loads the ae package in case it has not been loaded)\r
+%  and with or without the french(le) package.\r
+%\r
+% In order to get the guillemets, it is necessary to either type\r
+% \guillemotleft and \guillemotright, or to use an 8 bit encoding\r
+% (such as ISO-Latin1) which selects these two commands, \r
+% or, if you use the french package (but not the frenchle package), \r
+% to type << or >>.\r
+%\r
+% By default, you get the Polish CMR guillemets; if this package is loaded\r
+% with the `cm' option, you get the LASY guillemets; with `ec,' you\r
+% get the EC guillemets, and with `cyr,' you get the cyrillic guillemets.\r
+%\r
+% In verbatim mode, you always get the EC/TT guillemets.\r
+%\r
+% The default option is interesting in conjunction with PDF,\r
+% because there is a Type 1 version of the Polish CMR fonts\r
+% and these guillemets are very close in shape to the EC guillemets.\r
+% There are no free Type 1 versions of the EC fonts.\r
+%\r
+% Support for Polish CMR guillemets was kindly provided by \r
+% Rolf Niepraschk <niepraschk@ptb.de> in version 0.99 (2000/05/22).\r
+% Bernd Raichle provided extensive simplifications to the code\r
+% for version 1.00.\r
+%\r
+% This package is released under the LPPL.\r
+%\r
+% Changes:\r
+%   Date        version\r
+%   2001/04/12  1.01    the frenchle and french package are now distinguished.\r
+%\r
+\def\fileversion{1.01}\r
+\def\filedate{2001/04/12}\r
+\NeedsTeXFormat{LaTeX2e}\r
+%\ProvidesPackage{aeguill}[2001/04/12 1.01 %    % GM\r
+%AE fonts with french guillemets (D. Roegel)]   % GM - keeping the log file clean(er)\r
+%\RequirePackage{ae}  % GM May 2007 - already embedded here\r
+\r
+\newcommand{\@ae@switch}[4]{#4}\r
+\DeclareOption{ec}{\renewcommand\@ae@switch[4]{#1}}\r
+\DeclareOption{cm}{\renewcommand\@ae@switch[4]{#2}}\r
+\DeclareOption{cyr}{\renewcommand\@ae@switch[4]{#3}}\r
+\DeclareOption{pl}{\renewcommand\@ae@switch[4]{#4}}\r
+\ExecuteOptions{pl}\r
+\ProcessOptions\r
+\r
+%\r
+% Load necessary packages\r
+%\r
+\@ae@switch{% ec\r
+  % do nothing\r
+}{% cm\r
+  \RequirePackage{latexsym}%  GM - May 2007 - already 'mentioned as required' up above\r
+}{% cyr\r
+  \RequirePackage[OT2,T1]{fontenc}%\r
+}{% pl\r
+  \RequirePackage[OT4,T1]{fontenc}%\r
+}\r
+\r
+% The following command will be compared to \frenchname,\r
+% as defined in french.sty and frenchle.sty.\r
+\def\aeguillfrenchdefault{french}%\r
+\r
+\let\guill@verbatim@font\verbatim@font\r
+\def\verbatim@font{\guill@verbatim@font\ecguills{cmtt}%\r
+                   \let\guillemotleft\@oguills\let\guillemotright\@fguills}\r
+\r
+\begingroup \catcode`\<=13 \catcode`\>=13\r
+\def\x{\endgroup\r
+ \def\ae@lfguill{<<}%\r
+ \def\ae@rfguill{>>}%\r
+}\x\r
+\r
+\newcommand{\ecguills}[1]{%\r
+  \def\selectguillfont{\fontencoding{T1}\fontfamily{#1}\selectfont}%\r
+  \def\@oguills{{\selectguillfont\symbol{19}}}%\r
+  \def\@fguills{{\selectguillfont\symbol{20}}}%\r
+  } \r
+\r
+\newcommand{\aeguills}{%\r
+  \ae@guills\r
+  % We redefine \guillemotleft and \guillemotright\r
+  % in order to catch them when they are used \r
+  % with \DeclareInputText (in latin1.def for instance)\r
+  % We use \auxWARNINGi as a safe indicator that french.sty is used.\r
+  \gdef\guillemotleft{\ifx\auxWARNINGi\undefined\r
+                         \@oguills % neither french.sty nor frenchle.sty\r
+                      \else\r
+                         \ifx\aeguillfrenchdefault\frenchname\r
+                           \ae@lfguill  % french.sty\r
+                         \else\r
+                           \@oguills    % frenchle.sty\r
+                         \fi\r
+                      \fi}%\r
+  \gdef\guillemotright{\ifx\auxWARNINGi\undefined\r
+                         \@fguills % neither french.sty nor frenchle.sty\r
+                       \else\r
+                         \ifx\aeguillfrenchdefault\frenchname\r
+                           \ae@rfguill  % french.sty\r
+                         \else\r
+                           \@fguills    % frenchle.sty\r
+                         \fi\r
+                       \fi}%\r
+  }\r
+\r
+%\r
+% Depending on the class option\r
+% define the internal command \ae@guills\r
+\@ae@switch{% ec\r
+  \newcommand{\ae@guills}{%\r
+    \ecguills{cmr}}%\r
+}{% cm\r
+  \newcommand{\ae@guills}{%\r
+    \def\selectguillfont{\fontencoding{U}\fontfamily{lasy}%\r
+            \fontseries{m}\fontshape{n}\selectfont}%\r
+    \def\@oguills{\leavevmode\nobreak\r
+                \hbox{\selectguillfont (\kern-.20em(\kern.20em}\nobreak}%\r
+    \def\@fguills{\leavevmode\nobreak\r
+                \hbox{\selectguillfont \kern.20em)\kern-.2em)}%\r
+                \ifdim\fontdimen\@ne\font>\z@\/\fi}}%\r
+}{% cyr\r
+  \newcommand{\ae@guills}{%\r
+    \def\selectguillfont{\fontencoding{OT2}\fontfamily{wncyr}\selectfont}%\r
+    \def\@oguills{{\selectguillfont\symbol{60}}}%\r
+    \def\@fguills{{\selectguillfont\symbol{62}}}}\r
+}{% pl\r
+  \newcommand{\ae@guills}{%\r
+    \def\selectguillfont{\fontencoding{OT4}\fontfamily{cmr}\selectfont}%\r
+    \def\@oguills{{\selectguillfont\symbol{174}}}%\r
+    \def\@fguills{{\selectguillfont\symbol{175}}}}\r
+}\r
+\r
+\r
+\AtBeginDocument{%\r
+  \ifx\GOfrench\undefined\r
+    \aeguills\r
+  \else\r
+    \let\aeguill@GOfrench\GOfrench\r
+    \gdef\GOfrench{\aeguill@GOfrench \aeguills}%\r
+  \fi\r
+  }\r
+\r
+\endinput\r
+%\r
+%~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\r
+\r

diff --git a/sigcse2009/sigcse2009.tex b/sigcse2009/sigcse2009.tex
new file mode 100644 (file)
index 0000000..ec3f8f2
--- /dev/null
+++ b/sigcse2009/sigcse2009.tex
@@ -0,0 +1,112 @@
+% This is "sig-alternate.tex" V1.8 June 2007
+% This file should be compiled with V2.3 of "sig-alternate.cls" June 2007
+%
+% This example file demonstrates the use of the 'sig-alternate.cls'
+% V2.3 LaTeX2e document class file. It is for those submitting
+% articles to ACM Conference Proceedings WHO DO NOT WISH TO
+% STRICTLY ADHERE TO THE SIGS (PUBS-BOARD-ENDORSED) STYLE.
+% The 'sig-alternate.cls' file will produce a similar-looking,
+% albeit, 'tighter' paper resulting in, invariably, fewer pages.
+%
+% ----------------------------------------------------------------------------------------------------------------
+% This .tex file (and associated .cls V2.3) produces:
+%       1) The Permission Statement
+%       2) The Conference (location) Info information
+%       3) The Copyright Line with ACM data
+%       4) NO page numbers
+%
+% as against the acm_proc_article-sp.cls file which
+% DOES NOT produce 1) thru' 3) above.
+%
+% Using 'sig-alternate.cls' you have control, however, from within
+% the source .tex file, over both the CopyrightYear
+% (defaulted to 200X) and the ACM Copyright Data
+% (defaulted to X-XXXXX-XX-X/XX/XX).
+% e.g.
+% \CopyrightYear{2007} will cause 2007 to appear in the copyright line.
+% \crdata{0-12345-67-8/90/12} will cause 0-12345-67-8/90/12 to appear in the copyright line.
+%
+% ---------------------------------------------------------------------------------------------------------------
+% This .tex source is an example which *does* use
+% the .bib file (from which the .bbl file % is produced).
+% REMEMBER HOWEVER: After having produced the .bbl file,
+% and prior to final submission, you *NEED* to 'insert'
+% your .bbl file into your source .tex file so as to provide
+% ONE 'self-contained' source file.
+%
+% ================= IF YOU HAVE QUESTIONS =======================
+% Questions regarding the SIGS styles, SIGS policies and
+% procedures, Conferences etc. should be sent to
+% Adrienne Griscti (griscti@acm.org)
+%
+% Technical questions _only_ to
+% Gerald Murray (murray@acm.org)
+% ===============================================================
+%
+% For tracking purposes - this is V1.8 - June 2007
+
+\documentclass{sig-alternate}
+
+\begin{document}
+%
+% --- Author Metadata here ---
+\conferenceinfo{SIGCSE}{'09 Chattanooga, Tennessee, USA}
+%\CopyrightYear{2007} % Allows default copyright year (200X) to be over-ridden - IF NEED BE.
+%\crdata{0-12345-67-8/90/01}  % Allows default copyright data (0-89791-88-6/97/05) to be over-ridden - IF NEED BE.
+% --- End of Author Metadata ---
+
+\title{The Pintos Instructional Operating System Kernel}
+
+\subtitle{[Draft]}
+
+\numberofauthors{3}
+\author{
+% 1st. author
+\alignauthor Ben Pfaff\\
+       \affaddr{Nicira Networks}\\
+       \affaddr{Palo Alto, CA}\\
+       \email{blp@nicira.com}
+% 2nd. author
+\alignauthor Anthony Romano\\
+       \affaddr{Stanford University}\\
+       \affaddr{Palo Alto, CA}\\
+       \email{ajromano@stanford.edu}
+% 3rd. author
+\alignauthor Godmar Back\\
+       \affaddr{Virginia Tech}\\
+       \affaddr{Blacksburg}\\
+       \email{gback@cs.vt.edu}
+}
+
+\maketitle
+\begin{abstract}
+\input{abstract}
+\end{abstract}
+
+% A category with the (minimum) three required fields
+%\category{H.4}{Information Systems Applications}{Miscellaneous}
+%A category including the fourth, optional field follows...
+%\category{D.2.8}{Software Engineering}{Metrics}[complexity measures, performance measures]
+
+%\terms{Fill in terms here if we need them}
+
+%\keywords{Fill in keywords here if we need them}
+
+\input{introduction}
+
+\input{principles}
+
+\input{assignments}
+
+\input{rest}
+
+% remove the following line before submitting!
+\nocite{*}
+
+
+\bibliographystyle{abbrv}
+
+%
+%
+\bibliography{sigcse2009}  % sigproc.bib is the name of the Bibliography in this case
+\end{document}