/
index.html
2297 lines (2212 loc) · 102 KB
/
index.html
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<!DOCTYPE html>
<html lang="en">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<meta name="generator" content="AsciiDoc 8.6.7">
<title></title>
<style type="text/css">
/* Shared CSS for AsciiDoc xhtml11 and html5 backends */
/* Default font. */
body {
font-family: Georgia,serif;
}
/* Title font. */
h1, h2, h3, h4, h5, h6,
div.title, caption.title,
thead, p.table.header,
#toctitle,
#author, #revnumber, #revdate, #revremark,
#footer {
font-family: Arial,Helvetica,sans-serif;
}
body {
margin: 1em 5% 1em 5%;
}
a {
color: blue;
text-decoration: underline;
}
a:visited {
color: fuchsia;
}
em {
font-style: italic;
color: navy;
}
strong {
font-weight: bold;
color: #083194;
}
h1, h2, h3, h4, h5, h6 {
color: #527bbd;
margin-top: 1.2em;
margin-bottom: 0.5em;
line-height: 1.3;
}
h1, h2, h3 {
border-bottom: 2px solid silver;
}
h2 {
padding-top: 0.5em;
}
h3 {
float: left;
}
h3 + * {
clear: left;
}
h5 {
font-size: 1.0em;
}
div.sectionbody {
margin-left: 0;
}
hr {
border: 1px solid silver;
}
p {
margin-top: 0.5em;
margin-bottom: 0.5em;
}
ul, ol, li > p {
margin-top: 0;
}
ul > li { color: #aaa; }
ul > li > * { color: black; }
pre {
padding: 0;
margin: 0;
}
#author {
color: #527bbd;
font-weight: bold;
font-size: 1.1em;
}
#email {
}
#revnumber, #revdate, #revremark {
}
#footer {
font-size: small;
border-top: 2px solid silver;
padding-top: 0.5em;
margin-top: 4.0em;
}
#footer-text {
float: left;
padding-bottom: 0.5em;
}
#footer-badges {
float: right;
padding-bottom: 0.5em;
}
#preamble {
margin-top: 1.5em;
margin-bottom: 1.5em;
}
div.imageblock, div.exampleblock, div.verseblock,
div.quoteblock, div.literalblock, div.listingblock, div.sidebarblock,
div.admonitionblock {
margin-top: 1.0em;
margin-bottom: 1.5em;
}
div.admonitionblock {
margin-top: 2.0em;
margin-bottom: 2.0em;
margin-right: 10%;
color: #606060;
}
div.content { /* Block element content. */
padding: 0;
}
/* Block element titles. */
div.title, caption.title {
color: #527bbd;
font-weight: bold;
text-align: left;
margin-top: 1.0em;
margin-bottom: 0.5em;
}
div.title + * {
margin-top: 0;
}
td div.title:first-child {
margin-top: 0.0em;
}
div.content div.title:first-child {
margin-top: 0.0em;
}
div.content + div.title {
margin-top: 0.0em;
}
div.sidebarblock > div.content {
background: #ffffee;
border: 1px solid #dddddd;
border-left: 4px solid #f0f0f0;
padding: 0.5em;
}
div.listingblock > div.content {
border: 1px solid #dddddd;
border-left: 5px solid #f0f0f0;
background: #f8f8f8;
padding: 0.5em;
}
div.quoteblock, div.verseblock {
padding-left: 1.0em;
margin-left: 1.0em;
margin-right: 10%;
border-left: 5px solid #f0f0f0;
color: #888;
}
div.quoteblock > div.attribution {
padding-top: 0.5em;
text-align: right;
}
div.verseblock > pre.content {
font-family: inherit;
font-size: inherit;
}
div.verseblock > div.attribution {
padding-top: 0.75em;
text-align: left;
}
/* DEPRECATED: Pre version 8.2.7 verse style literal block. */
div.verseblock + div.attribution {
text-align: left;
}
div.admonitionblock .icon {
vertical-align: top;
font-size: 1.1em;
font-weight: bold;
text-decoration: underline;
color: #527bbd;
padding-right: 0.5em;
}
div.admonitionblock td.content {
padding-left: 0.5em;
border-left: 3px solid #dddddd;
}
div.exampleblock > div.content {
border-left: 3px solid #dddddd;
padding-left: 0.5em;
}
div.imageblock div.content { padding-left: 0; }
span.image img { border-style: none; }
a.image:visited { color: white; }
dl {
margin-top: 0.8em;
margin-bottom: 0.8em;
}
dt {
margin-top: 0.5em;
margin-bottom: 0;
font-style: normal;
color: navy;
}
dd > *:first-child {
margin-top: 0.1em;
}
ul, ol {
list-style-position: outside;
}
ol.arabic {
list-style-type: decimal;
}
ol.loweralpha {
list-style-type: lower-alpha;
}
ol.upperalpha {
list-style-type: upper-alpha;
}
ol.lowerroman {
list-style-type: lower-roman;
}
ol.upperroman {
list-style-type: upper-roman;
}
div.compact ul, div.compact ol,
div.compact p, div.compact p,
div.compact div, div.compact div {
margin-top: 0.1em;
margin-bottom: 0.1em;
}
tfoot {
font-weight: bold;
}
td > div.verse {
white-space: pre;
}
div.hdlist {
margin-top: 0.8em;
margin-bottom: 0.8em;
}
div.hdlist tr {
padding-bottom: 15px;
}
dt.hdlist1.strong, td.hdlist1.strong {
font-weight: bold;
}
td.hdlist1 {
vertical-align: top;
font-style: normal;
padding-right: 0.8em;
color: navy;
}
td.hdlist2 {
vertical-align: top;
}
div.hdlist.compact tr {
margin: 0;
padding-bottom: 0;
}
.comment {
background: yellow;
}
.footnote, .footnoteref {
font-size: 0.8em;
}
span.footnote, span.footnoteref {
vertical-align: super;
}
#footnotes {
margin: 20px 0 20px 0;
padding: 7px 0 0 0;
}
#footnotes div.footnote {
margin: 0 0 5px 0;
}
#footnotes hr {
border: none;
border-top: 1px solid silver;
height: 1px;
text-align: left;
margin-left: 0;
width: 20%;
min-width: 100px;
}
div.colist td {
padding-right: 0.5em;
padding-bottom: 0.3em;
vertical-align: top;
}
div.colist td img {
margin-top: 0.3em;
}
@media print {
#footer-badges { display: none; }
}
#toc {
margin-bottom: 2.5em;
}
#toctitle {
color: #527bbd;
font-size: 1.1em;
font-weight: bold;
margin-top: 1.0em;
margin-bottom: 0.1em;
}
div.toclevel0, div.toclevel1, div.toclevel2, div.toclevel3, div.toclevel4 {
margin-top: 0;
margin-bottom: 0;
}
div.toclevel2 {
margin-left: 2em;
font-size: 0.9em;
}
div.toclevel3 {
margin-left: 4em;
font-size: 0.9em;
}
div.toclevel4 {
margin-left: 6em;
font-size: 0.9em;
}
span.aqua { color: aqua; }
span.black { color: black; }
span.blue { color: blue; }
span.fuchsia { color: fuchsia; }
span.gray { color: gray; }
span.green { color: green; }
span.lime { color: lime; }
span.maroon { color: maroon; }
span.navy { color: navy; }
span.olive { color: olive; }
span.purple { color: purple; }
span.red { color: red; }
span.silver { color: silver; }
span.teal { color: teal; }
span.white { color: white; }
span.yellow { color: yellow; }
span.aqua-background { background: aqua; }
span.black-background { background: black; }
span.blue-background { background: blue; }
span.fuchsia-background { background: fuchsia; }
span.gray-background { background: gray; }
span.green-background { background: green; }
span.lime-background { background: lime; }
span.maroon-background { background: maroon; }
span.navy-background { background: navy; }
span.olive-background { background: olive; }
span.purple-background { background: purple; }
span.red-background { background: red; }
span.silver-background { background: silver; }
span.teal-background { background: teal; }
span.white-background { background: white; }
span.yellow-background { background: yellow; }
span.big { font-size: 2em; }
span.small { font-size: 0.6em; }
span.underline { text-decoration: underline; }
span.overline { text-decoration: overline; }
span.line-through { text-decoration: line-through; }
div.unbreakable { page-break-inside: avoid; }
/*
* xhtml11 specific
*
* */
tt {
font-family: "Courier New", Courier, monospace;
font-size: inherit;
color: navy;
}
div.tableblock {
margin-top: 1.0em;
margin-bottom: 1.5em;
}
div.tableblock > table {
border: 3px solid #527bbd;
}
thead, p.table.header {
font-weight: bold;
color: #527bbd;
}
p.table {
margin-top: 0;
}
/* Because the table frame attribute is overriden by CSS in most browsers. */
div.tableblock > table[frame="void"] {
border-style: none;
}
div.tableblock > table[frame="hsides"] {
border-left-style: none;
border-right-style: none;
}
div.tableblock > table[frame="vsides"] {
border-top-style: none;
border-bottom-style: none;
}
/*
* html5 specific
*
* */
.monospaced {
font-family: "Courier New", Courier, monospace;
font-size: inherit;
color: navy;
}
table.tableblock {
margin-top: 1.0em;
margin-bottom: 1.5em;
}
thead, p.tableblock.header {
font-weight: bold;
color: #527bbd;
}
p.tableblock {
margin-top: 0;
}
table.tableblock {
border-width: 3px;
border-spacing: 0px;
border-style: solid;
border-color: #527bbd;
border-collapse: collapse;
}
th.tableblock, td.tableblock {
border-width: 1px;
padding: 4px;
border-style: solid;
border-color: #527bbd;
}
table.tableblock.frame-topbot {
border-left-style: hidden;
border-right-style: hidden;
}
table.tableblock.frame-sides {
border-top-style: hidden;
border-bottom-style: hidden;
}
table.tableblock.frame-none {
border-style: hidden;
}
th.tableblock.halign-left, td.tableblock.halign-left {
text-align: left;
}
th.tableblock.halign-center, td.tableblock.halign-center {
text-align: center;
}
th.tableblock.halign-right, td.tableblock.halign-right {
text-align: right;
}
th.tableblock.valign-top, td.tableblock.valign-top {
vertical-align: top;
}
th.tableblock.valign-middle, td.tableblock.valign-middle {
vertical-align: middle;
}
th.tableblock.valign-bottom, td.tableblock.valign-bottom {
vertical-align: bottom;
}
/*
* manpage specific
*
* */
body.manpage h1 {
padding-top: 0.5em;
padding-bottom: 0.5em;
border-top: 2px solid silver;
border-bottom: 2px solid silver;
}
body.manpage h2 {
border-style: none;
}
body.manpage div.sectionbody {
margin-left: 3em;
}
@media print {
body.manpage div#toc { display: none; }
}
</style>
<script type="text/javascript">
/*<+'])');
// Function that scans the DOM tree for header elements (the DOM2
// nodeIterator API would be a better technique but not supported by all
// browsers).
var iterate = function (el) {
for (var i = el.firstChild; i != null; i = i.nextSibling) {
if (i.nodeType == 1 /* Node.ELEMENT_NODE */) {
var mo = re.exec(i.tagName);
if (mo && (i.getAttribute("class") || i.getAttribute("className")) != "float") {
result[result.length] = new TocEntry(i, getText(i), mo[1]-1);
}
iterate(i);
}
}
}
iterate(el);
return result;
}
var toc = document.getElementById("toc");
if (!toc) {
return;
}
// Delete existing TOC entries in case we're reloading the TOC.
var tocEntriesToRemove = [];
var i;
for (i = 0; i < toc.childNodes.length; i++) {
var entry = toc.childNodes[i];
if (entry.nodeName.toLowerCase() == 'div'
&& entry.getAttribute("class")
&& entry.getAttribute("class").match(/^toclevel/))
tocEntriesToRemove.push(entry);
}
for (i = 0; i < tocEntriesToRemove.length; i++) {
toc.removeChild(tocEntriesToRemove[i]);
}
// Rebuild TOC entries.
var entries = tocEntries(document.getElementById("content"), toclevels);
for (var i = 0; i < entries.length; ++i) {
var entry = entries[i];
if (entry.element.id == "")
entry.element.id = "_toc_" + i;
var a = document.createElement("a");
a.href = "#" + entry.element.id;
a.appendChild(document.createTextNode(entry.text));
var div = document.createElement("div");
div.appendChild(a);
div.className = "toclevel" + entry.toclevel;
toc.appendChild(div);
}
if (entries.length == 0)
toc.parentNode.removeChild(toc);
},
/////////////////////////////////////////////////////////////////////
// Footnotes generator
/////////////////////////////////////////////////////////////////////
/* Based on footnote generation code from:
* http://www.brandspankingnew.net/archive/2005/07/format_footnote.html
*/
footnotes: function () {
// Delete existing footnote entries in case we're reloading the footnodes.
var i;
var noteholder = document.getElementById("footnotes");
if (!noteholder) {
return;
}
var entriesToRemove = [];
for (i = 0; i < noteholder.childNodes.length; i++) {
var entry = noteholder.childNodes[i];
if (entry.nodeName.toLowerCase() == 'div' && entry.getAttribute("class") == "footnote")
entriesToRemove.push(entry);
}
for (i = 0; i < entriesToRemove.length; i++) {
noteholder.removeChild(entriesToRemove[i]);
}
// Rebuild footnote entries.
var cont = document.getElementById("content");
var spans = cont.getElementsByTagName("span");
var refs = {};
var n = 0;
for (i=0; i<spans.length; i++) {
if (spans[i].className == "footnote") {
n++;
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<body class="article">
<div id="header">
</div>
<div id="content">
<div class="sect1">
<h2 id="_dvcs_workflows">DVCS Workflows</h2>
<div class="sectionbody">
<div class="paragraph"><p>Zachary Kessin
<a href="mailto:zkessin@gmail.com">zkessin@gmail.com</a>
@zkessin</p></div>
</div>
</div>
<div class="sect1">
<h2 id="_introducing_git_and_hg">Introducing Git and HG</h2>
<div class="sectionbody">
<div class="paragraph"><p>This book is not about version control. That is a radical statement as
it says "Using Git and Mercurial" on the cover, but its not about git
or mercurial, nor is it about software development, though most of the
readers will be software developers. What this book is about is teams.</p></div>
<div class="paragraph"><p>Its not just software, many things worth doing these days are done by
teams of people. While most people who use GitHub are programmers
and will use it to write programs.</p></div>
<div class="paragraph"><p>GitHub can be used (And for
those of you who know nothing about knitting, to say knitters are
passionate about what they do would be an understatement)</p></div>
<div class="sect2">
<h3 id="_thanks">Thanks</h3>
<div class="paragraph"><p>This book was envisioned as a collaborative project. I wanted to hear
how other people have collaborated on projects, find out what works
and what doesn’t.</p></div>
<div class="paragraph"><p>In developing this book I have to thank several people, First of all
Simon St Lawrence and Andy Oram at O’Reilly Media who have supported
me.</p></div>
<div class="paragraph"><p>Matthew McCullough of the GitHub training group has offered me a
number of suggestions as well as promoted this book within GitHub.</p></div>
<div class="paragraph"><p>In addition a number of people have sent me pull requests with
changes. Contributors are listed here in alphabetical order by GitHub user
name.</p></div>
<div class="ulist"><ul>
<li>
<p>
breskeby - Rene Groeschke
</p>
</li>
<li>
<p>
kirean - Erik Andersson
</p>
</li>
<li>
<p>
rkessin - Richard Kessin
</p>
</li>
</ul></div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_tools_for_collaboration">Tools for Collaboration</h2>
<div class="sectionbody">
<div class="paragraph"><p>When working with a group on a project, you need to have a way to
integrate the contributions of various team members.</p></div>
<div class="paragraph"><p>It is possible to write in software like MS Word and email copies of
the files around between collaborators. However this is a risky
practice. As revisions of the file move around, the number of versions
of the file will go up. Trying to ensure that changes are not
overwritten by mistake becomes an increasingly difficult task.</p></div>
<div class="paragraph"><p>Given enough contributers and enough versions of the file it is
inevitable that someone’s changes will get lost or that an older
version of a paragraph will suddenly return when someone uses the
wrong version of a file.</p></div>
<div class="paragraph"><p>Sharing the file on a site like dropbox is also not a solution because if
more than one person wishes to edit at the same time it is impossible
to know which version of the file will be there when everyone is done.</p></div>
<div class="sect2">
<h3 id="_les_bons_comptes_font_les_bons_amis">Les bons comptes font les bons amis</h3>
<div class="paragraph"><p>The quote in French means "Good accounts make for good
friends" and is fitting. As business venture needs a good system to
track its money, and a project needs a good system to keep track of
the work done by its members.</p></div>
<div class="paragraph"><p>A project can be any form of creative work, a computer program, a
Novel, this book, a set of knitting patterns and so forth. Most
projects will consist of one or more files that will reside on the
computers of the project members.</p></div>
<div class="paragraph"><p>As an example take this book. It consists of around 20 or so files
that contain the actual text of the book, one for each chapter or
section, and then a bunch of other files that contain things like the
images that are included and a few random others.</p></div>
<div class="paragraph"><p>As the book is being written we want to be able to share those
documents between the writers, reviewers, editors, and in this case
the world at large. Other projects will be shared in different ways.</p></div>
<div class="paragraph"><p>In order to make this collaboration work we need two things. First a
way to share the documents between the project members, and secondly a
set of rules on how those contributors will work together.</p></div>
<div class="paragraph"><p>It is all fine and good to say that it is possible to know if two
users have the same version of a file, or how their copies differ, but
if you have 20 people attempting to assemble a complex project you
need a way to organize people so that tasks can be managed.</p></div>
<div class="paragraph"><p>This book will attempt to lay out how to construct a system that will
work for your team, by showing how different teams have faced these
problems and mapping out their solutions.</p></div>
</div>
<div class="sect2">
<h3 id="_version_control">Version Control</h3>
<div class="paragraph"><p>Thankfully various computer programmers over the years have faced this
problem and realizing that it was a problem, built tools to try and
solve it. These tools collectively are known as "Version Control
Systems" Or "Revision Control Systems". The history of Version
Control systems dates back to the 1970’s and has generated significant
progress.</p></div>
<div class="paragraph"><p>The current major Version Control system is called "git" and was
created by Linus Torvolds, when he was unable to find that existing
systems did not meet the needs of the team that was developing the
Linux kernel.</p></div>
</div>
<div class="sect2">
<h3 id="_git">GIT</h3>
<div class="paragraph"><p>GIT is a very powerful tool that has a lot of features, but most of
what is needed to work and collaborate with others can be done with a
small enough to learn pretty quickly. In addition while many git
tutorials show how to use git from a command line there are now many
very nice graphical tools to enable the use of git without having to
ever see a command line if you don’t want too.</p></div>
<div class="paragraph"><p>The way version control systems work is they track files and changes
to those files. So it is possible to see the history of changes to a
file and when each line was last changed and by whom.</p></div>
<div class="paragraph"><p>This allows project members to say that they all the same version of a
file, and to ensure that everyone’s changes have been accounted
for. Git allows users to ensure that they have the same version of the
project files by applying a mathematical function called SHA1 to the
files in a project. At any given time the files committed to a project
will have a unique SHA1 key.</p></div>
<div class="paragraph"><p>Furthermore, if two members of project team have a project directory
with the same SHA1 key they can be sure that the files in the project
are the same.</p></div>
<div class="paragraph"><p>Every time files are changed in a project git will create a new SHA1
key for the project. So if Bob and Lisa want to know if they have the
same files they do not have to check every file for changes they can
just compare their keys. If they match they know that the files are
the same.</p></div>
<div class="paragraph"><p>However if they are not the same git can look at the history of the
files and figure out what has changed. So if Bob has sent Lisa file
for editing and she made some changes, git will use the SHA1 keys to
compare the history of the files. In this case it will see that Bob’s
files are an ancestor to Lisa’s. It can then know exactly what changes
Lisa made and allow Bob to safely merge her changes. We will see
an example of how to do this in <a href="#pull_request">Pull Request</a>.</p></div>
<div class="sect3">
<h4 id="_sha1">SHA1</h4>
<div class="paragraph"><p>SHA1 is a cryptographic hash that when you apply it to data will
return a 40 character string that looks like this,
<strong>3fee35069bb9591edc3ab76f44b69c7b2d44be88</strong>.</p></div>
<div class="admonitionblock">
<table><tr>
<td class="icon">
<div class="title">Note</div>
</td>
<td class="content">you can not recover the original files from that hash, SHA1 is
strictly a one way function.</td>
</tr></table>
</div>
<div class="paragraph"><p>In general you will see a shorter form that looks like <strong>3fee350</strong>. In
this case git will use as short a version of the string as it can as
long as it is unique. Git does this because the developers realized
that having to use a 40 character string would be difficult for
users.</p></div>
<div class="paragraph"><p>The details of how SHA1 turns arbitrary data into a hash are rather
technical. If you want to know more about how SHA1 works you can look
on <a href="http://en.wikipedia.org/wiki/Sha1">WIkipedia</a>.</p></div>
<div class="paragraph"><p>The thing to remember is that the chances that two SHA1 keys will be
the same while the files are not is 1:10<sup>48</sup>. That is close enough to
0 for me.</p></div>
</div>
</div>
<div class="sect2">
<h3 id="_github">GitHub</h3>
<div class="paragraph"><p>The use of git is greatly enhanced by <a href="http://github.com">GitHub</a> a
company that was founded in 2008 to facilitate using git to
collaborate on software projects. Since the GitHub has grown to become
the most popular site for building collaborations in the open source
software community.</p></div>
<div class="paragraph"><p>GitHub is itself a distributed company with its team spread out all
over the place so they not only develop the tools for working with
distributed teams, they use them ever day.</p></div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_using_git">Using Git</h2>
<div class="sectionbody">
<div class="paragraph"><p>For developers who are used to centralized version control systems
like CVS or SVN transitioning to GIT requires a bit of a mental
transition. Unlike SVN a commit in git is a two phase operation. When
you do a <strong>git commit</strong> you are committing to your local repository. It
does not publish those changes to anyone else. This has several
benefits, first of all you can commit work in progress without woring
about "breaking the build" so if you may want to roll back some
changes you can commit to a branch on your local repository. It also
means that you do not need Internet access to commit to your local
repository. So if you are say writing a book on your laptop while on
an international flight (which is where this is being written) you can
check in your changes to a local repository and then push them to a
shared repository later when you flight lands.</p></div>
<div class="paragraph"><p>This chapter is not a full introduction to git. There are several
excellent books on that including <em>Version Control with Git</em> by Jon
Loeliger and McCullough which is published by O’Reilly. That book is
an excellent introduction to git. In addition there are several other
books out there as well as videos which can be found on sites like
youtube and infoq.</p></div>
<div class="paragraph"><p>In addition this chapter assumes the use of git from a command shell
such as bash. For those who are happy using a command line this can be
a very productive way to work. But do not assume that it is the only
way to work with GIT or even the "correct" way. The command line is an
effective way to work, but so are a number of Graphical git clients
which are covered in <a href="#git_gui">GUI Git Front Ends</a>. Use which ever
makes most sense to you. In addition it is quite possible to use both
the command line and one or more graphical tools.</p></div>
<div class="paragraph"><p>When building this book I have been using command line git tool, and
the Emacs git interface and the GitHub for mac program. In this case
I used the emacs client for most commits and the GitHub for Mac for
handling pushing and branches.</p></div>
<div class="sect2">
<h3 id="_creating_a_repository">Creating a repository</h3>
<div class="paragraph"><p>To create a repository use the command <strong>git init</strong> which will
initialize an empty git repository. Once a repository has been
created files can be added to it and all other operations performed.</p></div>
<div class="paragraph"><p>The other way to create a repository is by doing it with GitHub or
other remote hosting service. Once you create the repository on GitHub
you then clone the repository onto your local computer.</p></div>
</div>
<div class="sect2">
<h3 id="_basic_operations">Basic Operations</h3>
<div class="paragraph"><p>The first thing you will wish to do after creating a new repository is add
some files for it to track. A repository without any files is not
particularly useful, anymore than any other file system without files.</p></div>
<div class="paragraph"><p>To add files use the command <strong>git add <file></strong> you can also add more
than one file or a directory structure in one command line.</p></div>
<div class="sect3">
<h4 id="_committing_changes">Committing Changes</h4>
<div class="paragraph"><p>Once you have added files to a repository you will need to commit
changes that have been made. to do this you use <strong>git commit</strong>. Git
will open an editor to let you create a commit message. If you want to
supply one on the command line use <strong>git commit -m "My Commit Message"
file</strong>.</p></div>
<div class="admonitionblock">
<table><tr>
<td class="icon">
<div class="title">Warning</div>
</td>
<td class="content">unlike CVS and SVN if you do a commit in a subdirectory it
will commit all files in the repository, not just those in the current
repository.</td>
</tr></table>
</div>
</div>
<div class="sect3">
<h4 id="_branching_and_merging">Branching and Merging</h4>
<div class="paragraph"><p>Git makes dealing with branches much easier than svn or the like. Many
git users will create a new branch for each feature. This also allows
you to easily throw away changes did work well by simply abandoning
the branch.</p></div>
<div class="paragraph"><p>To create a branch use <strong>git branch <branchname></strong> this will create a new
branch, however it will not change repository to the new branch, do do