diff -r bec9a89f3b60 -r a201667fa696 versionControl/vcs.tex
--- a/versionControl/vcs.tex	Sun Jan 30 01:06:47 2011 +0530
+++ b/versionControl/vcs.tex	Sun Jan 30 01:08:21 2011 +0530
@@ -27,7 +27,7 @@
 \definecolor{darkgreen}{rgb}{0,0.5,0}
 
 \usepackage{listings}
-\lstset{language=Python,
+\lstset{language=bash,
     basicstyle=\ttfamily\bfseries,
     commentstyle=\color{red}\itshape,
   stringstyle=\color{darkgreen},
@@ -50,22 +50,6 @@
 
 \newcommand{\kwrd}[1]{ \texttt{\textbf{\color{blue}{#1}}}  }
 
-%%% This is from Fernando's setup.
-% \usepackage{color}
-% \definecolor{orange}{cmyk}{0,0.4,0.8,0.2}
-% % Use and configure listings package for nicely formatted code
-% \usepackage{listings}
-% \lstset{
-%    language=Python,
-%    basicstyle=\small\ttfamily,
-%    commentstyle=\ttfamily\color{blue},
-%    stringstyle=\ttfamily\color{orange},
-%    showstringspaces=false,
-%    breaklines=true,
-%    postbreak = \space\dots
-% }
-
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 % Title page
 \title[Version Control Systems]{SEES: Version Control Systems}
 
@@ -73,21 +57,6 @@
 
 \institute[IIT Bombay] {Department of Aerospace Engineering\\IIT Bombay}
 \date[]{}
-%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-
-%\pgfdeclareimage[height=0.75cm]{iitmlogo}{iitmlogo}
-%\logo{\pgfuseimage{iitmlogo}}
-
-
-%% Delete this, if you do not want the table of contents to pop up at
-%% the beginning of each subsection:
-\AtBeginSubsection[]
-{
-  \begin{frame}<beamer>
-    \frametitle{Outline}
-    \tableofcontents[currentsection,currentsubsection]
-  \end{frame}
-}
 
 \AtBeginSection[]
 {
@@ -97,12 +66,6 @@
   \end{frame}
 }
 
-% If you wish to uncover everything in a step-wise fashion, uncomment
-% the following command: 
-%\beamerdefaultoverlayspecification{<+->}
-
-%%\includeonlyframes{current,current1,current2,current3,current4,current5,current6}
-
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 % DOCUMENT STARTS
 \begin{document}
@@ -118,863 +81,394 @@
   % You might wish to add the option [pausesections]
 \end{frame}
 
-%% There are some %$ used just to minimise the effect of $ sign used in lstlisting. In emacs it looks unhealthy.
+%% There are some %$ used just to minimise the effect of $ sign used
+%% in lstlisting. In emacs it looks dirty. 
 
 % Introduction to course-need of version control, history, options available.
 \section{Introduction}
 
+\begin{frame}
+  \frametitle{What is Version Control?}
+  \begin{block}{}
+    A way to track changes made to files over time, by keeping copies
+    of files as we change them.
+  \end{block}
+\end{frame}
+
 %% Home made version control system?
 \begin{frame}[fragile]
-  \frametitle{Home-brew}
+  \frametitle{Home-brewed}
   \begin{center}
-    \includegraphics[height=1.8in,width=4.2in]{folder.png}
+    An example of a \typ{home-brew} Version Control system
+    \includegraphics[height=1.8in,width=4.2in]{images/folder.png}
   \end{center}
-  \begin{lstlisting}
+  \begin{lstlisting} 
 $ ls
 a.out  id1.txt  id2.txt  identifier.cpp  id.txt  lex  pda1.cpp  pda2.cpp  pda.cpp  pda.txt  string.txt
   \end{lstlisting} %%$
-    %%a screen-shot of folder with all crazy names.  
+    %%a screen-shot of folder with all crazy names.
 \end{frame}
 
 \begin{frame}[fragile]
-  \frametitle{Problems with such nomenclature}  
+  \frametitle{Problems}  
   \begin{block}{}    
   \begin{itemize}
-  \item Difficult to relate to content of file.
-  \item Cant track changes done to file.
-  \item It wont scale.
+  \item Name and changes made are not related or linked. 
+  \item Can't track sequence of changes made to a file. 
+  \item Does not scale. 
   \end{itemize}
     \end{block}
 \end{frame}
 
-\begin{frame}
-  \frametitle{What is version control}
-  \begin{block}{From a blog post}
-    ``Version control (or source control) is nothing more than keeping copies of work as we make changes to it.''
-  \end{block}
-\end{frame}
-
 \begin{frame}[fragile]
-  \frametitle{Need of Version Control}
+  \frametitle{The need for Version Control}
   \begin{itemize}
-  \item Track the history and evolution of a program.
-  \item To collaborate effectively on a project.
-  \item \begin{color}{red}``To err is Human''\end{color} for recovery we have ...
+  \item \alert{To err is Human} \ldots 
+  \item Tracking the history and evolution of a project
+  \item To collaborate effectively on a project
+  \item To efficiently track down bugs and pin-point the changes that
+    caused it 
   \end{itemize}
 \end{frame}
 
 %% Introduction to how logs are managed in VCS.
 %% A analogy in logs and day-to-day life?
 \begin{frame}[fragile]
-  \frametitle{How does it work? Analogy}
-  It can roughly be related to Computer/Video Games.
+  \frametitle{How does it work? --- Analogy}
+  It is, in some ways, similar to playing an Video game.
+  \begin{itemize}
+  \item We play games in stages
+  \item Once we finish a stage or a task -- \alert{we SAVE}
+  \item We continue playing
+  \item But, if necessary, we could choose from one of the saved
+    states and start from there
+  \item We could alter the course of the game
+  \end{itemize}
+\end{frame}
+
+
+\begin{frame}
+  \frametitle{Mercurial or \typ{hg}}
+  \begin{center}
+    \includegraphics[height=.75in,interpolate=true]{images/mercurial_logo}
+  \end{center}
+  \begin{itemize}
+  \item Easy to learn and use
+  \item Lightweight
+  \item Scales excellently
+  \item Written in Python
+  \end{itemize}
+\end{frame}
+
+\begin{frame}
+  \frametitle{Installation}
   \begin{itemize}
-  \item We play games in stages.
-  \item We pass a stage/task- \begin{color}{red}we SAVE the game.\end{color}
-  \item We resume playing from there onwards.
-  \item In-case we want to replay or revisit some particular stage, we start from position we saved earlier.
-  \item Even we can change the course of play henceforth.
+  \item \typ{sudo apt-get install mercurial}
+  \item TortoiseHg
+  \item \typ{\$ hg}
+  \item \typ{\$ hg version}
+  \end{itemize}
+\end{frame}
+
+\section{Let there be a Repo!}
+% init, status, commit, log, [ui]
+\begin{frame}
+  \frametitle{We need a repo!}
+  \begin{itemize}
+  \item A Repository (repo) is where all the action is!
+  \item Project's files plus a special folder that stores all the
+    changes
+  \item We take snapshots of the whole repository; not individual
+    files. 
+  \end{itemize}
+\end{frame}
+
+\begin{frame}
+  \frametitle{Initializing a repo}
+  \begin{itemize}
+  \item \typ{\$ hg init}
+  \item Creates a fresh repository
+  \item Adds a \typ{.hg} directory to our \emph{Working directory}
+  \end{itemize}
+  \emphbar{\typ{.hg} directory keeps log of changes made henceforth}
+\end{frame}
+
+\begin{frame}
+  \frametitle{Status report}
+  \begin{itemize}
+  \item \typ{hg status} gives the status of our repo
+  \item Use it often; at least as a beginner
+  \item \typ{hg help command} gives us help about \typ{command}
   \end{itemize}
 \end{frame}
 
 \begin{frame}[fragile]
-  \frametitle{Better way to say:}
-  \begin{center}
-    \includegraphics[height=2.5in,width=2.5in, interpolate=true]{mario}
-  \end{center}  
-  \emphbar{VCS provides power to save and resume from a stage.}
+  \frametitle{Status codes}
+  \begin{lstlisting}
+    M = modified                                               
+    A = added                                                  
+    R = removed                                                
+    C = clean                                                  
+    ! = missing 
+    ? = not tracked                                            
+    I = ignored                                                
+  \end{lstlisting}
+\end{frame}
+
+\begin{frame}
+  \frametitle{Adding files}
+  \begin{itemize}
+  \item From \typ{hg status} we know, none of the files are being
+    tracked, yet. 
+  \item \typ{hg add} --- asking \typ{hg} to track these files
+  \item As expected \typ{hg status} prepends an \typ{A} to the file names.
+  \end{itemize}
 \end{frame}
 
 \begin{frame}
-  \frametitle{How is it done?}
+  \frametitle{Taking Snapshots}
   \begin{itemize}
-  \item It keeps track of changes you make to a file. You can improve, revisit, and amend.
-  \item All changes are logged/recorded, so you and others can follow the development cycle.
-  \end{itemize}  
+  \item \typ{hg commit}
+  \item Asking Mercurial to take a snapshot; remember the changes made
+    to the repository. 
+  \item Commit message is a description of the changes made. 
+  \end{itemize}
 \end{frame}
 
-
-%% Introduction to jargon 
-%% This should have some excerpts from normal systems.
-%% Like diffs, folders etc.
-
-%% \section{Learning the Lingo!}
-
-%% \begin{frame}[fragile]
-%%   \frametitle{Common jargon: Basic setup}
-%%   \begin{lstlisting}
-%% $ ls slides/
-%% filter.png  lena_mean.png  lena.png  
-%% neighbour.png  pool.aux  pool.log  
-%% pool.nav  pool.out  pool.pdf  pool.snm  
-%% pool.tex  pool.tex~  pool.toc  pool.vrb    
-%%   \end{lstlisting}  %%$
-%%   \begin{itemize}
-%%   \item Repository(repo):\\
-%%         The folder with all files.
-%%   %% \item Server:\\
-%%   %%       Machine with main inventory/repo.
-%%   %% \item Client:\\
-%%   %%       Local machines with copy of main repo.
-%%   \end{itemize}
-%% \end{frame}
-
-%% \begin{frame}[fragile]
-%%   \frametitle{Actions}
-%%   \begin{itemize}
-%%   \item Add:\\
-%%     Creating/Copying files(cp, touch).
-%%   \item Check out/Clone:\\
-%%     Creating copy of working folder.
-%%   \end{itemize}
-%%   \begin{lstlisting}
-%% $ cp -rv circulate/ local
-%% `circulate/' -> `local'
-%% `circulate/sslc1.txt' -> `local/sslc1.txt'
-%% `circulate/pos.txt' -> `local/pos.txt'
-%% `circulate/pendulum.txt' -> `local/pendulum.txt'
-%% `circulate/lena.png' -> `local/lena.png'
-%% `circulate/sslc1.py' -> `local/sslc1.py'
-%% `circulate/points.txt' -> `local/points.txt'    
-%%   \end{lstlisting}  %%$
-%% \end{frame}
-
-%% \begin{frame}
-%%   \frametitle{Actions cont...}
-%%   \begin{itemize}
-%%     \item Version:\\
-%%     Version number(Die Hard 4.0).\\
-%%     Making changes to folder, changes state/version.
-%%     \item Head/Tip:\\
-%%     Most recent revision/stage.
-%%     \item Commit:\\
-%%     Saving(recording) a change.
-%%   \item Change log/History:\\
-%%     List of all past changes.
-%%   \end{itemize}
-%% \end{frame}
-
-%% \begin{frame}
-%%   \frametitle{Actions cont...}
-%%   \begin{itemize}
-%%   \item Branch:\\
-%%     Separate local copy for bug fixing, testing.
-%%   \item Diff/Change:\\
-%%     Changes made in a file in two different versions.
-%%   \item Merge (or patch):\\
-%%     Appling the changes to file, to make it up-to-date.
-%%   \item Conflict:\\
-%%     When merging a file is not obvious.
-%%   \item Resolve:\\
-%%     Fixing the conflict manually.
-%%   \end{itemize}
-%% \end{frame}
-
-%% % Types of Version Controls
-%% %% \section{Types of VCS}
-
-%% %% \begin{frame}
-%% %%   \frametitle{Types:}
-%% %%   Based on ways of managing the repo there are two types of VCS:
-%% %%   \begin{itemize}
-%% %%   \item Centralized VCS\\
-%% %%     cvs, svn fall under this category.
-%% %%   \item Distributed VCS\\
-%% %%     hg, bzr, git follows this methodology.
-%% %%   \end{itemize}
-%% %%   \emphbar{We would be covering \typ{hg}}
-%% %% \end{frame}
-
 \begin{frame}
-  \frametitle{We will cover hg?}
-    \includegraphics[height=.75in, interpolate=true]{mercurial}\\
-  Because it is:
+  \frametitle{Thumbnail views}
   \begin{itemize}
-  \item Easy to learn and use.
-  \item Lightweight.
-  \item Scales excellently.
-  \item Written in Python.
+  \item \typ{hg log}~ gives the log of the changes made
+  \item A \typ{changeset} is an atomic collection of changes to the
+    files (between successive commits)
   \end{itemize}
-  \inctime{15}
-\end{frame}
-
-% Initializing the repo, cloning, committing changes, pushing, pulling to repo.
-\section{Getting Started}
-
-\begin{frame}
-  \frametitle{Objective}
-  \begin{block}{}
-    We will \alert{manage} letters collaboratively using \typ{hg}.
-  \end{block}
-
-  %% \pause
-  %% \begin{block}{Disclaimer}
-  %%   Please note, objective is not to learn creative writing, but to learn \alert{hg(mercurial)} via \alert{interesting} use case.
-  %% \end{block}    
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Getting comfortable:}
-  For checking \typ{hg} installation and its version type:
-  \begin{lstlisting}
-    $ hg version    
-  \end{lstlisting}
-  To get broad help on \typ{hg} and commands available:
-  \begin{lstlisting}
-    $ man hg
-    $ hg help
-  \end{lstlisting}
-  To get help on particular \typ{hg} related option try:
-  \begin{lstlisting}
-    $ hg help diff
-  \end{lstlisting} %$
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Getting working/existing code base}
-  To get an already existing code base:
-  \begin{lstlisting}
-$ hg clone 
-http://hg.serpentine.com/tutorial/hello 
-localCopyhello
-  \end{lstlisting}
-\typ{localCopyhello} is copy of code-base. 
-  \begin{lstlisting}
-$ ls localCopyhello/
-hello.c  Makefile
-  \end{lstlisting}
-\end{frame}
-
-%%introduction to clone, repo, server, client.
-\begin{frame}[fragile]
-  \frametitle{What did we do!}
-  \begin{block}{Explanation}
+  \begin{block}{Log information}
     \begin{itemize}
-    \item<1-> \typ{hello} is a \alert{repo}, it's a collection of files and folders. 
-    \item<2-> This repo is located on remote(\alert{server}) machine.    
-    \item<3-> We copy(\alert{clone}) repo to our local machine.
+    \item \alert{changeset}: Identifiers for the changeset
+    \item \alert{user}: Details of user who created the changeset
+    \item \alert{date}: Date and time of creation
+    \item \alert{summary}: One line description
     \end{itemize}    
   \end{block}
 \end{frame}
 
-\begin{frame}[fragile]
-  \frametitle{Creating repo of existing files}
-  I have some files which I want to bring under version control. \typ{hg} provides \alert{\typ{init}} command for this: 
-  \begin{lstlisting}
-$ ls -a circulate/
-.  ..  lena.png  pendulum.txt  points.txt  pos.txt  sslc1.py  sslc1.txt
-$ cd circulate/
-$ hg init
-$ ls -a
-.  ..  .hg  lena.png  pendulum.txt  points.txt  pos.txt  sslc1.py  sslc1.txt    
-  \end{lstlisting}
-  \emphbar{\typ{.hg} directory keeps log of changes made henceforth.}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Starting fresh}
-  We can use \typ{init} to start a new repository also
-  \begin{lstlisting}
-$ mkdir letter
-$ cd letter
-$ touch letter.tex
-$ ls -a
-.  ..  letter.tex
-$ hg init
-$ ls -a
-.  ..  letter.tex  .hg
-  \end{lstlisting}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Making copies: Branching}
-  All \typ{hg} repositories are self-contained, and independent which can be copied(cloned):
-  \begin{lstlisting}
-$ hg clone localCopyhello newCopy
-updating working directory
-2 files updated, 0 files merged, 
-0 files removed, 0 files unresolved
-  \end{lstlisting}
-  \alert{or}
-  \begin{lstlisting}
-$ hg clone letter letter-clone
-updating working directory
-0 files updated, 0 files merged, 
-0 files removed, 0 files unresolved 
- \end{lstlisting}
-\end{frame}
-
-%%introduction to branch
-\begin{frame}[fragile]
-  \frametitle{Why do we need branching?}
-  \begin{block}{}
-    \begin{itemize}
-    \item To keep separate set for \alert{experimentation}.
-    \item Simple way to \alert{backup} all in one go!
-    \item It helps in collaborative environment.
-    %% should we mention it at all? there is no need to know atleast here.
-    %% syncing and integrating in backup files and testing environment can also be mentioned.
-    \end{itemize}
-  \end{block}
-  \inctime{15}
-\end{frame}
-
-%% Should we here stress on how are distribute VCS have 
-%% different approach then centralized ones? Maybe a pic
-%% or some other graphical representation.
-\begin{frame}[fragile]
-  \frametitle{Revisiting saved points:history/logs}
-  In \typ{hg}, the difference between consecutive stages is termed as \alert{changeset}.\\
-  Once we have saved stages, we need a mechanism to review and access them, for that use \alert{\typ{log}} command.
-  \begin{lstlisting}
-$ cd localCopyhello
-$ hg log    
-  \end{lstlisting}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Understanding output}
-  It provides following information:
+\begin{frame}
+  \frametitle{User information}
   \begin{itemize}
-  \item \alert{changeset}: Identifiers for the changeset.
-  \item \alert{user}: Person who created the changeset.
-  \item \alert{date}: Date and time of creation of changeset.
-  \item \alert{summary}: One line description.
-  \end{itemize}
-\end{frame}
-
-%% here we should have image of dotA or halo for resuming from a stage in game.
-
-\begin{frame}[fragile]
-  \frametitle{History/Logs cont...}
-  By default \typ{log} returns complete list of all changes. \\
-  For selective view try:
-\begin{lstlisting}
-$ hg log -r 3
-$ hg log -r 2:4
-\end{lstlisting}
-  tip/latest changes can be seen via:
-  \begin{lstlisting}
-$ hg tip    
-  \end{lstlisting} %%$
-  \inctime{5}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Advancing through a stage:status}
-  We often need to add/delete some files from directory(repo). The structure keeps on evolving, and tools for handling them are needed.\\
-  We will use the \typ{letter} repo we created earlier.
-  \begin{lstlisting}
-$ cd letter
-$ hg log
-$ hg st
-? letter.tex
-  \end{lstlisting} %%$
-  \alert{\typ{st}} (aka status) is command to show changed files in the working directory.\\
-\end{frame}
-
-%% track record is confusing for some. Duma have some doubts :(
-\begin{frame}[fragile]
-  \frametitle{Adding files}
-  "?" indicates that this file are aliens to track record.\\
-  \alert{\typ{add}} command is available to add new files to present structure.
-  \begin{lstlisting}
-$ hg add letter.tex
-$ hg st
-A letter.tex
-  \end{lstlisting}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Saving present stage: committing}
-  \emphbar{This is equivalent to completing tasks, before reaching a stage where you want to save.}
-  \typ{hg} uses \alert{\typ{ci}}(aka \typ{commit}) command to save changes. So after adding file, we have to commit it also:
-  \begin{lstlisting}
-$ hg ci -u "Shantanu <shantanu@fossee.in>" 
-        -m "First commit."
-$ hg log
-changeset:   0:210664b4ed58
-tag:         tip
-user:        Shantanu <shantanu@fossee.in>
-date:        Tue Feb 23 19:41:45 2010 +0530
-summary:     First commit.
-  \end{lstlisting}
-\end{frame}
-
-%% explanation of ci command??
-\begin{frame}[fragile]
-  \frametitle{\typ{ci} command}
-  Some arguments passed to \typ{ci} command are worth noticing:
-  \begin{itemize}
-  \item \alert{u}: To provide name and email contact information of person making changes!\\
-  In case you don't want to repeat that each time of committing, add info to \typ{hgrc} file.
-  \item<2-> \alert{m}: It is to provide one-line summary of changeset. \\
-    if this argument is not passed, hg takes you to editor to specify the message which is required to commit.
-  \end{itemize}  
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Other operations}
-  \typ{hg} supports basic file-management functions like copy, remove, rename etc.
-  \begin{lstlisting}
-$ hg cp letter.tex letter-prof.tex
-$ hg rename letter.tex letter-personal.tex
-$ hg st
-A letter-personal.tex
-A letter-pro.tex
-R letter.tex
-$ hg ci -u "Shantanu <shantanu@fossee.in>" 
-        -m "Renamed and added letters."
-$ hg tip| grep summary 
-summary:     Renamed and added letters.
-  \end{lstlisting} %$
-%% Other commands which can be handy are \typ{remove}, \typ{revert} etc.
-  \inctime{10}
-\end{frame}
-
-% Introduction to concepts of branches, merging patch?
-\section{Sharing and Collaborating}
-
-\begin{frame}[fragile]
-  \frametitle{Distributing changes}
-  \begin{itemize}
-  \item All directory-structure(repo) are self-contained.
-  \item Changes created are local.
+  \item User information is set in the \typ{hgrc} file
+  \item It can be set globally or local to the project
+  \item Global \typ{hgrc}
     \begin{itemize}
-    \item Until we sync. previously cloned repos.
+    \item \typ{\$HOME/.hgrc} -- Unix like systems
+    \item \typ{\%HOME\%\\.hgrc} -- Windows
     \end{itemize}
   \end{itemize}
-  \begin{lstlisting}
-$ cd letter-clone
-$ hg pull 
-pulling from /home/baali/letter
-requesting all changes
-adding changesets
-adding manifests
-adding file changes
-added 2 changesets with 2 changes to 2 files
-(run 'hg update' to get a working copy)
-  \end{lstlisting} %$
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Pulling changesets cont...}
-  \alert{\typ{pull}} command doesn't update current directory, it just imports changesets. To add all these changes, use \alert{\typ{up}}:
-  \begin{lstlisting}
-$ ls -a
-.  ..  .hg
-$ hg up
-2 files updated, 0 files merged, 
-0 files removed, 0 files unresolved
-$ ls -a
-.  ..  .hg  letter-personal.tex  
-letter-pro.tex
-  \end{lstlisting} %% $
-  \pause
-  \emphbar{Why \typ{pull} and \typ{up} are needed separately?}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Content of letter}
-  Personal letter can be letter to ask a girl out!\\
-  Using LaTeX to write letter, it would be straight forward:
-
-  \begin{small}  
-  \begin{block}{}
-  \begin{lstlisting}
-\documentclass{letter}
-\begin{document}
-\begin{letter}{}
-\opening{Hello Jas,}
-I really enjoyed meeting you in CS 101, 
-but would love to know you better. 
-How about a coffee on Thursday after class?
-
-\closing{-Samarth}
-\end{letter}
-\end{document}
-
-  \end{lstlisting}
-  \end{block}
-  \end{small}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Sharing the changes!}
-  \begin{lstlisting}    
-$ hg st
-M letter-personal.tex
-  \end{lstlisting} %%$
-  \alert{'M'} sign indicates that \typ{hg} has noticed change in that particular file.
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Revisiting changes}
-  To view changes made \typ{hg} provides \alert{\typ{diff}}:
-  \begin{small}      
-  \begin{lstlisting}
-$ hg diff
-diff -r 4a2d973a92de letter-personal.tex
---- a/letter-personal.tex	Tue Feb 23 19:50:39 2010 +0530
-+++ b/letter-personal.tex	Tue Feb 23 20:28:46 2010 +0530
-@@ -0,0 +1,11 @@
-+\documentclass{letter}
-+\begin{document}
-+ 
-+\begin{letter}{}
-+\opening{Hello Jas,}
-+  
-+I really enjoyed meeting you in CS 101, 
-.
-.
-  \end{lstlisting} %$
-  \end{small}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Saving the changes}
-  We have to commit these changes.
-  \begin{lstlisting}
-$ hg ci -u "Shantanu <shantanu@fossee.in>" 
-  -m "Added content to personal letter."
-  \end{lstlisting} %$
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Syncing two repos}
-  To bring both the repos at same stage we have to \alert{\typ{push}} changesets
-  \begin{lstlisting}
-$ hg push 
-pushing to /home/baali/letter
-searching for changes
-adding changesets
-adding manifests
-adding file changes
-added 1 changesets with 1 changes to 1 files
-  \end{lstlisting} %$
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Syncing cont...}
-  Same as \typ{pull}, \typ{push} wont update the main directory by default.
-  \begin{lstlisting}
-$ cd letter
-$ hg tip    
-$ cat letter-personal.tex
-  \end{lstlisting} %%$
-  \alert{\typ{tip}} shows latest changeset, but content of file are not updated.\\
-  We have to use \typ{up} on main branch
-  \begin{lstlisting}
-$ hg up
-1 files updated, 0 files merged, 0 files removed, 0 files unresolved    
-  \end{lstlisting} %$
-  \inctime{15}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Merging: Scenario}
-  One very useful feature is merging work of different peers working on same project.\\
-  We consider scenario, two person on one project, both have local copies, and one among them is main branch.\\
-  \begin{center}
-    \includegraphics[height=1in, interpolate=true]{scenario}
-  \end{center}  
-\end{frame}
-
-\begin{frame}
-  \frametitle{Scenario cont...}
-  \begin{block}{}
-  \begin{itemize}
-  \item To make this letter better, I ask for suggestions.
-  \item Friend of mine, clones this repo and edit things.
-  \item When he/she pushes changes, I can decide to use them or not.
-  \end{itemize}  
-  \end{block}  
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Creating more clones for sharing}
-  I create a clone of repo which is accessible to my friend.
-  \begin{lstlisting}
-$ hg clone letter letter-suggestion
-updating working directory
-2 files updated, 0 files merged, 0 files removed, 0 files unresolved
-  \end{lstlisting} %$
-\end{frame}
-
-%% here we can have introduction to concept of DVCS and CVCS?
-
-\begin{frame}[fragile]
-  \frametitle{Suggestions!}
-  He is convinced that using some colored text would be a good idea.
-  He just adds color to closing part.
-  %% a comment on how bad is this idea :P
-  \begin{small}      
-  \begin{lstlisting}
-$ hg dif
-diff -r 4a2d973a92de letter-personal.tex
---- a/letter-personal.tex	Tue Feb 23 19:50:39 2010 +0530
-+++ b/letter-personal.tex	Wed Feb 24 12:03:33 2010 +0530
-@@ -0,0 +1,12 @@
- \documentclass{letter}
-+\usepackage{color}
- \begin{document}
-.
--\closing{-Samarth}
-+\closing{\textcolor{red}{-Samarth}}
-  \end{lstlisting} %%$
-  \end{small}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Committing the changes}
-  He is satisfied with his minor changes, so he commits.
-  \begin{lstlisting}
-$ hg ci 
-  -u "Vattam <vattam@fossee.in>"
-  -m "Added some suggestions."   
-  \end{lstlisting} %%$
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{The other good half of repo...}
-  It turns out, in this process, Jas is already dating, so we edit the letter for someone else from same class.
-  \begin{lstlisting}
-$ hg ci -u "Shantanu <shantanu@fossee.in>"
-        -m "Changed name."
-$ hg tip|grep changeset
-changeset:   3:fadbd6492cc4    
-  \end{lstlisting}
-  %%\emphbar{\alert{moral:} Don't wait for it!}
-\end{frame}
-
-%%\hspace*{-0.5in} 
-
-\begin{frame}[fragile]
-  \frametitle{Situation}
-  \begin{columns}
-    \column{0.5\textwidth}    
-    \begin{block}{\center{main directory}}
-      \includegraphics[height=2in, interpolate=true]{glog-main}
-    \end{block}
-    \column{0.5\textwidth} 
-    \begin{block}{\center{cloned directory}}
-      \includegraphics[height=2in, interpolate=true]{glog-suggestion}
-    \end{block}
-  \end{columns}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Merging}
-  \emphbar{Lets sync both these branches!}
-  \begin{lstlisting}
-$ hg pull ../letter-suggestion
-pulling from ../letter-suggestion
-searching for changes
-adding changesets
-adding manifests
-adding file changes
-added 1 changesets with 1 changes to 1 files (+1 heads)
-(run 'hg heads' to see heads, 'hg merge' to merge)    
-  \end{lstlisting} %$
-  \begin{itemize}
-  \item \typ{pull} can be done from a branch explicitly also.
-  \pause
-  \item \alert{Output is already suggesting something!}
-  \end{itemize}  
-\end{frame}
-
-%% Here one can mention the point of having push and pull separate. Because of this policy, changes made are not lost.
-\begin{frame}[fragile]
-  \frametitle{Analyzing events in detail}
-  Since hg \typ{pull} don't update the files directly, our changes are still safe. \typ{hg} provides some commands to help understand such problems.
-\begin{tiny}
-  \begin{lstlisting}
-$ hg heads 
-changeset:   4:71fd776d856b
-tag:         tip
-parent:      2:a5d8cb2fac01
-user:        Vattam <vattam@fossee.in>
-date:        Wed Feb 24 12:54:31 2010 +0530
-summary:     Added some suggestions.
-
-changeset:   3:02b49a53063f
-user:        Shantanu <Shantanu@fossee.in>
-date:        Wed Feb 24 13:12:26 2010 +0530
-summary:     Changed name.
-  \end{lstlisting} %%$
-\end{tiny}
-  It shows current repository heads or show branch head
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{What went wrong: Analysis}
-    \begin{lstlisting}
-$ hg glog    
-  \end{lstlisting} %%$
-  \begin{center}
-  \includegraphics[height=2in]{heads}  
-  \end{center}  
-  It shows history alongside an ASCII revision graph.  
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{What went wrong: Analysis cont...}
-  Because of different 'pasts', \typ{up} command fails.
-  \begin{lstlisting}
-$ hg up
-abort: crosses branches (use 'hg merge' 
-       or 'hg update -C')
-  \end{lstlisting} %$
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Merging}
-  To deal such situations \typ{hg} \alert{merge} command merge working directory with another revision.
-  \begin{lstlisting}
-$ hg merge
- 1 files updated, 0 files merged, 0 files removed, 0 files unresolved
-(branch merge, don't forget to commit)   
-  \end{lstlisting} %$
-  After merging two branches, we have to commit the results to create a common head.
-  \begin{lstlisting}
-$ hg ci -u "Shantanu <shantanu@fossee.in>" 
-        -m "Merged branches."
-  \end{lstlisting} %$
-  \inctime{15}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{\typ{glog}}
-  \begin{center}
-  \includegraphics[height=2.8in]{glog-2}  
-  \end{center}
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{Revisiting history!}
-  In case earlier girl is available again and you are still looking for date you can \alert{revert} back to previous letter!
-  \begin{lstlisting}
-$ hg revert -r 2 -a
-reverting letter-personal.tex    
-  \end{lstlisting} %%$
-  And the content changes. From here on you can further change your letter as you wish.
-  %% more options for revert are to explained here!
-\end{frame}
-
-\begin{frame}[fragile]
-  \frametitle{More information}
-  \begin{itemize}
-  \item \typ{merge} fails if there are conflicting changes.
-    \begin{itemize}
-    \item Like two persons editing same file, same line and pushing it upstream.
-    \end{itemize}
-  \item In conflicts, one have to perform \typ{merge} manually.
-  \item \typ{hg} provides \alert{\typ{incoming}} command, which checks the would-be imported changes
-    \begin{itemize}
-    \item To avoid conflicting changes before importing.
-    \end{itemize}
-  \end{itemize}
-  \inctime{10}
-\end{frame}
-
-%% Manual and force merge
-%% hgignore
-
-%% Reverting to previous versions!
-% Steps to follow to make life easier. How to avoid/handle manual merges.
-\section{Work flow: DOs and DON'Ts}
-
-\begin{frame}
-  \frametitle{Motto behind hg}
-  \begin{center}
-  \color{red}{``Commit Early Commit Often.''}
-  \end{center}  
-\end{frame}
-
-\begin{frame}
-  \frametitle{Work-flow}
-  \begin{itemize}
-  \item Make changes.
-  \item Commit.
-  \item Pull changesets.
-  \item Merge(if required).
-  \item Push.
-  \end{itemize}
 \end{frame}
 
 \begin{frame}
-  \frametitle{Cheat Sheet}
-  \begin{center}
-  \includegraphics[height=2.8in]{mod}  
-  \end{center}  
-  \inctime{15}
+  \frametitle{\alert{Advice}: \typ{commits}, messages}
+  \begin{itemize}
+  \item Atomic changes; one change with one \typ{commit}
+  \item Single line summary --- 60 to 65 characters long
+  \item Followed by paragraphs of detailed description
+    \begin{itemize}
+    \item Why the change?
+    \item What does it effect?
+    \item Known bugs/issues?
+    \item etc. 
+    \end{itemize}
+  \end{itemize}
 \end{frame}
 
-%% Move it to end of session. Once introduction part is 
-%% over. Then mentioning about options and utility.
-\section{Use case and Options}
+\section{But Why \typ{commit}~?}
 
 \begin{frame}
-  \frametitle{Use cases}
-  \emphbar{For team of people working remotely(even different computers/machines) on a project, use of version control is inevitable!}
-  \vspace{0.15in}
-  \emphbar{For single person: managing projects and assignments becomes easy}
-  \vspace{0.15in}
-  \pause
-  \emphbar{\color{red}{It is a good habit!}}
+  \frametitle{Operational overhead?}
+  \begin{itemize}
+  \item But why do we \typ{commit}
+  \item Isn't all this just adding to operational costs?
+  \item Isn't all this a waste of time?
+  \end{itemize}
+  \begin{center}
+    \emphbar{No! You shall see the benefits, soon!}    
+  \end{center}
 \end{frame}
 
 \begin{frame}
-  \frametitle{What are other options!}
+  \frametitle{Revert Changes}
+  \begin{itemize}
+  \item Undo all changes; the editor can only do so much.
+  \item \typ{hg revert --all}
+  \item \typ{hg revert filename}
+  \item Present file, with changes --- \typ{filename.orig}
+  \end{itemize}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Viewing Changes}
+  \begin{itemize}
+  \item \typ{hg diff} --- all changes since last commit
+  \end{itemize}
+  \begin{block}{}
+    \begin{lstlisting}
+      - this line was deleted
+      + this line was added
+    \end{lstlisting}
+  \end{block}
+\end{frame}
+
+
+\begin{frame}[fragile]
+  \frametitle{Revision numbering}
   \begin{itemize}
-  \item cvs (Concurrent Version System)
-  \item svn (Subversion)
-  \item hg (Mercurial)
-  \item bzr (Bazaar)
-  \item git
+  \item \typ{changeset:   n:cbf6e2a375b4}
+  \item \typ{n} is the revision number
+  \item The revision number is local to a repository
+  \item \typ{cbf6e2a375b4} is the unique identifier
+  \end{itemize}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Using revision numbers}
+  \begin{itemize}
+  \item \typ{-r n} can be passed as arguments to commands to specify
+    the revision number
+  \item For instance, \typ{hg log -r0} 
+  \item \typ{m:n} specifies a range of revision numbers
+  \item \typ{-1} gives the \typ{tip}; Negative numbering can be used
   \end{itemize}
-  \inctime{5}
+\end{frame}
+
+\section{Collaborating with Mercurial}
+\begin{frame}[fragile]
+  \frametitle{Cloning Repositories}
+  \begin{itemize}
+  \item \typ{hg clone SOURCE [DEST]}
+  \item All \typ{hg} repositories are self-contained
+  \end{itemize}
+\end{frame}
+
+\begin{frame}[fragile]
+  \frametitle{Sharing Repositories}
+  \begin{itemize}
+  \item \typ{hg serve}
+  \item Can be cloned with \typ{hg clone http://my-ip-address:8000}
+  \item We share a central repository; work on our local copies. 
+  \item Set write permissions in \typ{.hg/hgrc}
+  \end{itemize}
+  \begin{lstlisting}
+    [web]
+    push_ssl=False
+    allow_push=*
+  \end{lstlisting}
 \end{frame}
 
 \begin{frame}
-  \frametitle{Suggested Readings:}
+  \frametitle{Sharing Changes}
+  \begin{itemize}
+  \item Use \typ{hg push} to push your \typ{commits}
+    (\typ{changesets}) to the central repository
+  \end{itemize}
+\end{frame}
+
+
+\begin{frame}
+  \frametitle{Pulling Changes}
+  \begin{itemize}
+  \item \typ{hg incoming} shows new \typ{changesets} in the server 
+  \item To get these \typ{changesets}, we use \typ{hg pull}
+  \item These changes do not affect our working directory
+  \item \typ{hg parent} shows the parents of the working directory
+  \end{itemize}
+\end{frame}
+
+\begin{frame}
+  \frametitle{Pulling Changes \ldots}
   \begin{itemize}
-  \item \url{http://mercurial.selenic.com/guide/}
-  \item \url{http://hgbook.red-bean.com/}    
-  \item \url{http://karlagius.com/2009/01/09/version-control-for-the-masses/}
-  \item Articles related to version control available on \url{http://betterexplained.com/}
-  \item \url{http://en.wikipedia.org/wiki/Revision_control}
-  \item \url{http://wiki.alliedmods.net/Mercurial_Tutorial}
-  \item Mario game images are taken from wikipedia.
+  \item \typ{hg update} will update the working directory 
+    \begin{itemize}
+    \item Updates to the \typ{tip} if no revision is specified
+    \item \typ{tip} is the most recently added changeset 
+    \item Can specify revision number to update to
+    \end{itemize}
+  \item \typ{hg tip} shows the \typ{tip} of the repository
+  \end{itemize}
+\end{frame}
+
+\begin{frame}
+  \frametitle{Simultaneous Changes}
+  \begin{itemize}
+  \item The logs of both repositories will be different
+  \item The repositories have diverged
+  \item \typ{hg push} fails, in such a scenario
+  \item \alert{Never, Never, Never, Ever} use \typ{hg push -f}
+  \end{itemize}
+\end{frame}
+
+\begin{frame}
+  \frametitle{Merging}
+  \begin{itemize}
+  \item Pull and merge, when \typ{abort: push creates new remote
+    heads!}
+  \item \typ{hg merge} will merge the two diverged heads
+  \item \typ{commit} after you have \typ{merged}!
   \end{itemize}
 \end{frame}
+
+\begin{frame}
+  \frametitle{Simultaneous Changes \ldots}
+  \begin{itemize}
+  \item \typ{outgoing} shows the \typ{changesets} that will be pushed
+  \item \typ{hg push} works!
+  \item Look at the `Change graph'!
+  \end{itemize}
+\end{frame}
+
+\begin{frame}
+  \frametitle{Simultaneous Conflicting Changes}
+  \begin{itemize}
+  \item What if the changes conflict? -- overlapping edits
+  \item \typ{hg push} fails; \typ{hg pull}; \typ{hg merge}
+  \item You now get a diff view with 3 panes 
+    \begin{itemize}
+    \item First --- current file
+    \item Second --- file with your changes
+    \item Third --- \typ{changesets} that you pulled
+    \end{itemize}
+  \item Resolve conflict and save
+  \item \typ{hg commit}; \typ{hg push}
+  \item Look at the `Change graph'!
+  \end{itemize}
+\end{frame}
+
+\section{Conclusion}
+
+\begin{frame}
+  \frametitle{\alert{Advice}: Work-flow}
+  General work-flow
+  \begin{itemize}
+  \item \typ{pull}; \typ{update}
+  \item Make changes
+  \item \typ{commit}
+  \item If changes on repo, \typ{pull} and \typ{merge}
+  \item \typ{push}
+  \end{itemize}
+  \emphbar{Commit Early, Commit Often}
+\end{frame}
+
+\begin{frame}
+  \frametitle{References}
+  \begin{itemize}
+  \item \href{http://betterexplained.com/articles/a-visual-guide-to-version-control/}{A Visual Guide to Version Control}
+  \item \href{http://karlagius.com/2009/01/09/version-control-for-the-masses/}{Version Control for the Masses}
+  \item \href{http://betterexplained.com/articles/intro-to-distributed-version-control-illustrated/}{(Illustrated) Intro to Distributed Version Control}
+  \item \href{http://mercurial.selenic.com/wiki/UnderstandingMercurial}{Understanding Mercurial}
+  \item \href{http://mercurial.selenic.com/wiki/Tutorial}{A Tutorial on Using Mercurial}
+  \item \href{http://hginit.com/}{Hg Init: a Mercurial tutorial}
+  \item \href{http://mercurial.selenic.com/wiki/BeginnersGuides}{Beginners Guides}
+  \item \href{http://software-carpentry.org/4_0/vc/}{Software Carpentry}
+  \end{itemize}
+\end{frame}
+
 \end{document}
 
-Some more suggestions from Nishanth:
-revert  
-resolve
-
-Notes
------
-
-From http://mercurial.selenic.com/
-
-Quick Start
-
-Clone a project and push changes
-
-$ hg clone http://selenic.com/repo/hello
-$ cd hello
-$ (edit files)
-$ hg add (new files)
-$ hg commit -m 'My changes'
-$ hg push
-
-
-Create a project and commit
-
-$ hg init (project-directory)
-$ cd (project-directory)
-$ (add some files)
-$ hg add
-$ hg commit -m 'Initial commit'