diff options
Diffstat (limited to 'doc/manual/book.xml')
| -rw-r--r-- | doc/manual/book.xml | 191 |
1 files changed, 189 insertions, 2 deletions
diff --git a/doc/manual/book.xml b/doc/manual/book.xml index 51fddadf1..3f6c4f549 100644 --- a/doc/manual/book.xml +++ b/doc/manual/book.xml @@ -12,11 +12,128 @@ <chapter> <title>Introduction</title> + <sect1> + <title>The problem space</title> + + <para> + Nix is a system for controlling the automatic creation and distribution + of data, such as computer programs and other software artifacts. This + is a very general problem, and there are many applications that fall + under this description. + </para> + + <sect2> + <title>Build management</title> + + <para> + Build management tools are used to perform <emphasis>software + builds</emphasis>, that is, the construction of derived products + such as executable programs from source code. A commonly used build + tool is Make, which is a standard tool on Unix systems. These tools + have to deal with several issues: + <itemizedlist> + <listitem> + <para> + </para> + </listitem> + </itemizedlist> + </para> + + </sect2> + + <sect2> + <title>Package management</title> + + <para> + After software has been built, is must also be + <emphasis>deployed</emphasis> in the intended target environment, + e.g., the user's workstation. Examples include the Red Hat package + manager (RPM), Microsoft's MSI, and so on. Here also we have to deal + with several issues: + <itemizedlist> + <listitem> + <para> + The <emphasis>creation</emphasis> of packages from some formal + description of what artifacts should be distributed in the + package. + </para> + </listitem> + <listitem> + <para> + The <emphasis>deployment</emphasis> of packages, that is, the + mechanism by which we get them onto the intended target + environment. This can be as simple as copying a file, but + complexity comes from the wide range of possible installation + media (such as a network install), and the scalability of the + process (if a program must be installed on a thousand systems, + we do not want to visit each system and perform some manual + steps to install the program on that system; that is, the + complexity for the system administrator should be constant, not + linear). + </para> + </listitem> + </itemizedlist> + </para> + </sect2> + + </sect1> + + <sect1> + <title>The Nix system</title> + + <para> + ... + </para> + + <para> + Existing tools in this field generally both a underlying model (such as + the derivation graph of build tools, or the versioning scheme that + determines when two packages are <quote>compatible</quote> in a package + management system) and a formalism that allows ... + </para> + + <para> + Following the principle of separation of mechanism and policy, the Nix + system separates the <emphasis>low-level aspect</emphasis> of file + system object management form the <emphasis>high-level + aspect</emphasis> of the ... + </para> + + </sect1> + + </chapter> + + + <!--======================================================================--> + + <chapter> + <title>A Guided Tour</title> + <para> - Nix is a system for the automatic creation and distribution of data, such - as computer programs and other software artifacts. + Bla bla </para> + </chapter> + + <!--======================================================================--> + + <chapter> + <title>Fix Language Reference</title> + + <para> + Bla bla + </para> + </chapter> + + + <!--======================================================================--> + + <chapter> + <title>Nix Syntax and Semantics</title> + + <para> + Bla bla + </para> </chapter> @@ -99,4 +216,74 @@ $ make install</screen> </chapter> + <!--======================================================================--> + + <appendix> + <title>Troubleshooting</title> + + <sect1> + <title>Database hangs</title> + + <para> + If Nix or Fix appear to hang immediately after they are started, Nix's + database is probably <quote>wedged</quote>, i.e., some process died + while it held a lock on the database. The solution is to ensure that + no other processes are accessing the database and then run the + following command: + </para> + + <screen> +$ db_recover -e -h <replaceable>prefix</replaceable>/var/nix/db</screen> + + <para> + Here, <replaceable>prefix</replaceable> should be replaced by Nix's + installation prefix. + </para> + + </sect1> + + + <sect1> + <title>Database logfile removal</title> + + <para> + Every time a Nix database transaction takes place, Nix writes a record + of this transaction to a <emphasis>log</emphasis> in its database + directory to ensure that the operation can be replayed in case of a + application or system crash. However, without manual intervention, + the log grows indefinitely. Hence, unused log files should be deleted + periodically. This can be accomplished using the following command: + </para> + + <screen> +$ rm `db_archive -a -h <replaceable>prefix</replaceable>/var/nix/db`</screen> + + </sect1> + + + </appendix> + + + <!--======================================================================--> + + <appendix> + <title>Known problems</title> + + <itemizedlist> + + <listitem> + <para> + Nix should automatically recover the Berkeley DB database. + </para> + </listitem> + + <listitem> + <para> + Nix should automatically remove Berkeley DB logfiles. + </para> + </listitem> + + </itemizedlist> + </appendix> + </book> |