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diff --git a/build_tools/larch8/larch0/docs/html/larch_intro.html b/build_tools/larch8/larch0/docs/html/larch_intro.html new file mode 100644 index 0000000..fb82fd6 --- /dev/null +++ b/build_tools/larch8/larch0/docs/html/larch_intro.html @@ -0,0 +1,318 @@ +<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/xhtml1-strict.dtd"> +<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> + +<html> +<head> +<meta http-equiv="Content-type" content="text/html; charset=utf-8" /> +<title>Introduction</title> +<!-- (en) Add your meta data here --> + +<link href="css/larchdocs.css" rel="stylesheet" type="text/css"/> +<!--[if lte IE 7]> +<link href="css/yaml/core/iehacks.css" rel="stylesheet" type="text/css" /> +<![endif]--> +</head> + +<body> +<!-- skip link navigation --> +<ul id="skiplinks"> + <li><a class="skip" href="#col1">Skip to main content (Press Enter).</a></li> +</ul> + +<div class="page_margins"> + <div class="page"> + <div id="top"><div id="tm"></div></div> + <!-- begin: #col1 --> + <div id="col1" role="main"> + <div id="col1_content"> + <div id="header" role="banner"> + <h1><span><em>live Arch Linux</em> builder</span></h1> + </div> + + <!-- begin: #col3 navigation column --> + <div id="col3" role="complementary"> + <div id="col3_content"> + <img class="indent2" alt="larch logo" src="css/screen/larch150x.png" width="150" height="150" /> + <div class="vlist"> + <ul> + <li><a href="index.html"><h6>Table Of Contents</h6></a></li> + <li><a href="larch_features.html"><h6>Next:</h6> + <div class="indent1">Features</div></a></li> + </ul> + </div> + </div> + </div> + <!-- end: #col3 --> + +<div class="larchdocs"> +<h2 id="pagetitle" level="1">Introduction</h2> + +<blockquote> +<h3>Warning</h3> + +<p><em>Before we get started I should point out that most of the +<em>larch</em> scripts must be run as root in order to do their work, +and that much of this work consists of deleting and overwriting files +and even complete directories. If just one of these is wrong it might make +quite a mess of your system. That is quite normal for an installer, +but you will be using it on a system that +is already configured and this is somewhat risky - if you set up your +configuration wrong (or if you or I made some other mistake ...), you +might find you have destroyed some important data and/or your system +doesn't work any more. But that's life - <strong>Share and +Enjoy!</strong></em> +</p> +</blockquote> + +<p>Below is the general introductory blurb, but for those who want to jump +straight in and try it out I would suggest the following pages as possible +starting points: +<ul> + <li><a href="larch_quick.html" >Quick Start with the GUI</a> + </li> + <li><a href="larch_quick-console.html" >Quick Start on the command line</a> + </li> +</ul> +</p> + +<h3><a name="live_system"></a>What is a <em>live</em> system?</h3> + +<p><em>larch</em> is a collection of scripts designed around the creation and +use of custom <em>live</em> media (USB-stick/CD/DVD) of <em>Arch Linux</em>. +A <em>live</em> operating system is one which can reside on a removable medium +and boot on (ideally) any computer (of compatible architecture) into which +it is inserted. This can be useful in quite a variety of situations, for +example for testing purposes, for rescue purposes on machines whose +installed operating system is broken, or as an installation medium (many +linux distributions use <em>live</em> systems as installers). But there +are also situations where a permanently installed <em>live</em> system +can offer advantages over a normal installation, perhaps because of the +compression or because a <em>live</em> system is quite robust - it is +in essence read-only (though there are ways of supporting data persistence), +and can be quite insensitive to hardware changes. +</p> + +<p>The main features of the <em>larch</em> system are listed on the +<a href="larch_features.html">Features</a> page, among the most +significant might be the use of <a href="profiles.html">'profiles'</a> +to define the characteristics of the system to be built, the ability +to install the <em>live</em> system to various media and simple support +of data persistence. In addition it tries to remain as close +to standard Arch Linux as possible, using (by default) the standard +kernel, the same initscripts, <em>mkinitcpio</em> for building the +<em>initramfs</em>, etc. +</p> + +<h3><a name="requirements"></a>Build system requirements</h3> + +<p><em>larch</em> has been designed to work without extensive demands on +the build system. Although it has been developed under <em>Arch Linux</em>, +<em>larch</em> should run on other <em>GNU/Linux</em> systems. By means +of a sort of bootstrapping, the required software has been kept to a +minimum - many of the build functions are carried out on the newly +installed <em>Arch</em> system using <em>chroot</em>. +For example, you do not need support for <em>squashfs</em> or <em>aufs</em> +on the build system. But basic utilities which are normally available on any +<em>GNU/Linux</em> system, such as <em>bash</em>, <em>file</em>, +<em>find</em>, <em>blkid</em>, <em>mkisofs</em> - and +of course <em>chroot</em> - are assumed to be present (on <em>Arch</em> +that is packages 'bash', 'e2fsprogs', 'util-linux-ng', +'coreutils', 'findutils', 'file', 'cdrkit'). +</p> + +<p> The <em>larch</em> scripts are written mainly in python, but snippets +of bash crop up here and there. +In addition to python you must also have the pexpect module available +(in <em>Arch</em> the 'python-pexpect' package). The (optional) GUI +requires pyqt. I'm not sure what the oldest supported versions are, +development was done using python-2.6 and pyqt-4.7. +I think python-2.5 should be alright, and I have heard that +pyqt-4.4 probably doesn't work. +</p> + +<h3><a name="cli_gui"></a>Command line vs. GUI</h3> + +<p> +The basic functionality of <em>larch</em> is provided by command-line scripts, +but a graphical user interface is available, to make it easier to see what +options are available and to avoid the need to remember and not mistype +obscure command line parameters. In addition to providing a front-end to the +main scripts the GUI also provides help with organising the configuration +files. +</p> + +<h3><a name="overview"></a>Overview</h3> + +<p>One design aim was easy customisation, so that even relatively inexperienced +users could build personalised <em>live</em> systems on USB-stick or CD/DVD, +containing whatever +packages they wanted and with their own personal configurations. The resulting +medium should also be usable for installation purposes, so that one has a +customised <em>Arch Linux</em> installation/rescue medium. As the content can +be chosen freely, a comfortable working environment is possible - in contrast +to the rather Spartan standard <em>Arch</em> installation CD. However, note +that it is also possible, using the officially supported <em>archiso</em>, to +produce a customised <em>Arch Linux</em> installation/rescue medium (see the +corresponding <em>Arch wiki</em> page). The approach taken by the two projects +is somewhat different so do have a look at both. Note that at the latest since +version 7, <em>larch</em> makes no pretence of a 'KISS' approach. The code is, +I'm afraid, rather complicated. The resulting <em>live</em> system should, +however, be very close to a normal non-<em>live Arch Linux</em> system (as +far as the <em>squashfs + aufs</em> basis allows). +</p> + +<p><em>larch</em> offers a flexible approach to building your +<em>live</em> media. You can use 'profiles' to determine what gets installed, +and how it is configured. The advantage of this method is that all your +specifications are kept together in a folder which can be used to rebuild the +same or a similar system at a later date. Alternatively you can do a normal +<em>Arch Linux</em> installation (if there is such a thing!) and then make a +<em>live</em> medium from this (e.g. by running <em>larch</em> on it from a +<em>live</em> medium). +</p> + +<p>The use of <em>squashfs</em> in the resulting system means that the space +occupied will be significantly less than in the 'raw' state, normally about a +third of the original. As a result of this decision, it is not possible to write +directly to the system - which would seem to be quite a drawback, though in +some situations it can even be an advantage. The use of <em>aufs</em> (a +'unification' file-system, originally based on <em>unionfs</em>) allows the +resulting system to use a writeable 'overlay', so that the system behaves in +most respects like a normal installation. Of course if the boot medium is not +writeable (e.g. a CD) it may be difficult to provide a persistent writeable +layer (full persistence, which would include kernel updates, is completely +impossible in such a situation). In that case, or in general if it is +desired that there is no +persistence (e.g. for 'kiosk' type situations), <em>tmpfs</em> (a +memory-based file-system) can be used for the writeable layer. +</p> + +<p>If the <em>larch</em> system is used in the same way as a normal +<em>Arch</em> installation, including package updates, the space saving +effect of the <em>squashfs</em> archive can be lost (updates cannot +modify the base archive, so they occupy additional space). At some point +it would then be desirable to rebuild the system. This should be fairly +straightforward, but it is not really the envisioned use of <em>larch</em> +media. +</p> + +<p>Hardware detection is provided by the same <em>udev</em> approach as is +used in a standard <em>Arch Linux</em> system. +</p> + +<p>The <em>larch</em> project comprises several components. The scripts for +building a <em>larch live</em> medium are in the <em>larch</em> package, which +need not itself be installed in the <em>live</em> system, though it may be +useful (and is indeed installed by default). Scripts and data for the +<em>live</em> environment are provided in the +<em>larch-live</em> package, which must be installed in the <em>live</em> +system. There is also an optional installer (<em>larchin</em>) which can +install the <em>live</em> system to hard disk, providing a convenient way +to install a ready-configured <em>Arch Linux</em> system. +</p> + +<p>As with <em>Arch Linux</em> in general <em>larch</em> is not really +designed for beginners - you should know your way around a +<em>GNU/Linux</em> system (preferably <em>Arch</em>!), and be aware of the +dangers of running such programs, such as corrupting your whole system. +In any case, I hope that the +documentation will be clear enough to help anyone who wants to exploit +<em>larch</em> to the full (feedback is welcome!).</p> + +<p><b>Space Requirements:</b> +You need quite a lot of space to create a <em>live Arch Linux</em> system. +Bear in mind that a complete <em>Arch Linux</em> system is installed, then, +additionally, a compressed ('squashed') version is made, and then perhaps +even a CD image (<em>iso</em>). +Building for a USB-stick requires slightly less space, as the iso-image is +not built. If building a <em>live</em> version of an existing +<em>Arch Linux</em> system, much less space is required as no new +system must be installed. +</p> + +<h3><a name="larch_installation"></a>Installation of the <em>larch</em> build +system</h3> + +<p>The recommended way of installing <em>larch</em> is by means of the setup +script, see <a href="larch_quick-console.html">here</a> for details. +This installs all the necessary packages to a working directory, and it +should also work on non-<em>Arch</em> linux systems. +</p> + +<p>The <em>larch</em> package may, however, be installed in the normal +<em>Arch Linux</em> way using <em>pacman</em>. This method will only work on +an <em>Arch</em> system, of course. The <em>larch</em> repository is at +<a href="ftp://ftp.berlios.de/pub/larch/larch8/i686/"> +<strong>berlios</strong></a>. +</p> + +<p>The <em>larch</em> command line scripts need to be started as root, and +each has a usage message (run with the '-h' option). The gui should be +started as a normal user (it uses <em>su</em>, or can be configured to +use <em>sudo</em> instead, to get administrator rights when needed). +</p> + +<h3><a name="larch_profiles"></a>Profiles</h3> + +<p>A <em>larch</em> 'profile' is a directory containing the information +needed to build a particular 'flavour' of <em>Arch Linux</em> as a +<em>live</em> system - which packages to install, and how it should be +set up. For details see <a href="profiles.html">Profiles</a>. +</p> + +<h3><a name="stages"></a>The stages of the build process</h3> + +<p>The starting point is an <em>Arch Linux</em> installation. This can +be an already existing one from which you want to make a <em>live</em> +version, or - the recommended approach - you can use the +'Installation' stage of the <em>larch</em> system +(using the <strong>archin.py</strong> script) to prepare this. +<em>archin</em> downloads all the desired packages (if they are not already +in the host's package cache) and installs them to a directory on the host. +See <a href="archin.html">this page</a> for details. +</p> + +<p>Once we have the <em>Arch Linux</em> installation this can be +processed to build the basis components for the <em>live</em> medium. The +installation is compressed into a <em>squashfs</em> archive, and an +overlay directory containing the necessary modifications to the base +system is built - a sort of 'patch' directory for the basic installation. +The latter contains a few necessary +adjustments for running as a <em>live</em> system and also the +customisations specified in the <em>profile</em>. The other important +component is the <em>initramfs</em>, which also needs to be adapted +to boot the <em>live</em> system. This processing is performed by the +<strong>larchify.py</strong> script, see +<a href="larchify.html">this page</a> for details. +</p> + +<p>When the 'larchification' has been completed, the components can +be packed together onto a boot medium together with a bootloader. The +<strong>live_iso.py</strong> script creates an <em>iso</em> file, which +can then be written to a CD or DVD, the <strong>live_part.py</strong> +script sets up a bootable partition on a disk(-like) device, such as a +USB stick. See <a href="medium.html">this page</a> for details. +</p> + +</div> + + + <div class="topref"><a href="#top">Top</a></div> + </div> + <!-- begin: #footer --> + <div id="footer"> + <div id="footer-content" role="contentinfo">© 2010 Michael Towers<br /> + Page layout assisted by <a href="http://www.yaml.de/">YAML</a> and + <a href="http://www.kuwata-lab.com/tenjin/">pyTenjin</a> + </div> + </div> + <!-- end: #footer --> + </div> + <!-- end: #col1 --> + <div id="bottom"><div id="bl"><div id="bm"></div></div></div> + </div> +</div> +<!-- full skiplink functionality in webkit browsers --> +<script src="css/yaml/core/js/webkit-focusfix.js" type="text/javascript"></script> +</body> +</html> |