2012 lines
		
	
	
	
		
			72 KiB
		
	
	
	
		
			XML
		
	
	
	
	
	
			
		
		
	
	
			2012 lines
		
	
	
	
		
			72 KiB
		
	
	
	
		
			XML
		
	
	
	
	
	
| <article xmlns="http://docbook.org/ns/docbook"
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|          xmlns:xlink="http://www.w3.org/1999/xlink"
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|          xml:id="sec-relnotes">
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| 
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| <title>Nix Release Notes</title>
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| 
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| 
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| 
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| <!--==================================================================-->
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| 
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| <section xml:id="ssec-relnotes-1.5.2"><title>Release 1.5.2 (May 13, 2013)</title>
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| 
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| <para>This is primarily a bug fix release.  It has contributions from
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| Eelco Dolstra, Lluís Batlle i Rossell and Shea Levy.</para>
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| 
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| </section>
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| 
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| 
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| <!--==================================================================-->
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| 
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| <section xml:id="ssec-relnotes-1.5.1"><title>Release 1.5.1 (February 28, 2013)</title>
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| 
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| <para>The bug fix to the bug fix had a bug itself, of course.  But
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| this time it will work for sure!</para>
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| 
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| </section>
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| 
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| 
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| <!--==================================================================-->
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| 
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| <section xml:id="ssec-relnotes-1.5"><title>Release 1.5 (February 27, 2013)</title>
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| 
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| <para>This is a brown paper bag release to fix a regression introduced
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| by the hard link security fix in 1.4.</para>
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| 
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| </section>
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| 
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| 
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| <!--==================================================================-->
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| 
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| <section xml:id="ssec-relnotes-1.4"><title>Release 1.4 (February 26, 2013)</title>
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| 
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| <para>This release fixes a security bug in multi-user operation.  It
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| was possible for derivations to cause the mode of files outside of the
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| Nix store to be changed to 444 (read-only but world-readable) by
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| creating hard links to those files (<link
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| xlink:href="https://github.com/NixOS/nix/commit/5526a282b5b44e9296e61e07d7d2626a79141ac4">details</link>).</para>
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| 
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| <para>There are also the following improvements:</para>
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| 
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| <itemizedlist>
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| 
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|   <listitem><para>New built-in function:
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|   <function>builtins.hashString</function>.</para></listitem>
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| 
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|   <listitem><para>Build logs are now stored in
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|   <filename>/nix/var/log/nix/drvs/<replaceable>XX</replaceable>/</filename>,
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|   where <replaceable>XX</replaceable> is the first two characters of
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|   the derivation.  This is useful on machines that keep a lot of build
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|   logs (such as Hydra servers).</para></listitem>
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| 
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|   <listitem><para>The function <function>corepkgs/fetchurl</function>
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|   can now make the downloaded file executable.  This will allow
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|   getting rid of all bootstrap binaries in the Nixpkgs source
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|   tree.</para></listitem>
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| 
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|   <listitem><para>Language change: The expression <literal>"${./path}
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|   ..."</literal> now evaluates to a string instead of a
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|   path.</para></listitem>
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| 
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| </itemizedlist>
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| 
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| </section>
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| 
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| 
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| <!--==================================================================-->
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| 
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| <section xml:id="ssec-relnotes-1.3"><title>Release 1.3 (January 4, 2013)</title>
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| 
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| <para>This is primarily a bug fix release.  When this version is first
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| run on Linux, it removes any immutable bits from the Nix store and
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| increases the schema version of the Nix store.  (The previous release
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| removed support for setting the immutable bit; this release clears any
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| remaining immutable bits to make certain operations more
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| efficient.)</para>
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| 
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| <para>This release has contributions from Eelco Dolstra and Stuart
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| Pernsteiner.</para>
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| 
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| </section>
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| 
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| 
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| <!--==================================================================-->
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| 
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| <section xml:id="ssec-relnotes-1.2"><title>Release 1.2 (December 6, 2012)</title>
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| 
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| <para>This release has the following improvements and changes:</para>
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| 
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| <itemizedlist>
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| 
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|   <listitem>
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|     <para>Nix has a new binary substituter mechanism: the
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|     <emphasis>binary cache</emphasis>.  A binary cache contains
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|     pre-built binaries of Nix packages.  Whenever Nix wants to build a
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|     missing Nix store path, it will check a set of binary caches to
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|     see if any of them has a pre-built binary of that path.  The
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|     configuration setting <option>binary-caches</option> contains a
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|     list of URLs of binary caches.  For instance, doing
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| <screen>
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| $ nix-env -i thunderbird --option binary-caches http://nixos.org/binary-cache
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| </screen>
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|     will install Thunderbird and its dependencies, using the available
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|     pre-built binaries in <uri>http://nixos.org/binary-cache</uri>.
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|     The main advantage over the old “manifest”-based method of getting
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|     pre-built binaries is that you don’t have to worry about your
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|     manifest being in sync with the Nix expressions you’re installing
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|     from; i.e., you don’t need to run <command>nix-pull</command> to
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|     update your manifest.  It’s also more scalable because you don’t
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|     need to redownload a giant manifest file every time.
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|     </para>
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| 
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|     <para>A Nix channel can provide a binary cache URL that will be
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|     used automatically if you subscribe to that channel.  If you use
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|     the Nixpkgs or NixOS channels
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|     (<uri>http://nixos.org/channels</uri>) you automatically get the
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|     cache <uri>http://nixos.org/binary-cache</uri>.</para>
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| 
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|     <para>Binary caches are created using <command>nix-push</command>.
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|     For details on the operation and format of binary caches, see the
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|     <command>nix-push</command> manpage.  More details are provided in
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|     <link xlink:href="http://lists.science.uu.nl/pipermail/nix-dev/2012-September/009826.html">this
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|     nix-dev posting</link>.</para>
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|   </listitem>
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| 
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|   <listitem>
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|     <para>Multiple output support should now be usable.  A derivation
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|     can declare that it wants to produce multiple store paths by
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|     saying something like
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| <programlisting>
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| outputs = [ "lib" "headers" "doc" ];
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| </programlisting>
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|     This will cause Nix to pass the intended store path of each output
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|     to the builder through the environment variables
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|     <literal>lib</literal>, <literal>headers</literal> and
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|     <literal>doc</literal>.  Other packages can refer to a specific
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|     output by referring to
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|     <literal><replaceable>pkg</replaceable>.<replaceable>output</replaceable></literal>,
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|     e.g.
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| <programlisting>
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| buildInputs = [ pkg.lib pkg.headers ];
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| </programlisting>
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|     If you install a package with multiple outputs using
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|     <command>nix-env</command>, each output path will be symlinked
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|     into the user environment.</para>
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|   </listitem>
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| 
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|   <listitem>
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|     <para>Dashes are now valid as part of identifiers and attribute
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|     names.</para>
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|   </listitem>
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| 
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|   <listitem>
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|     <para>The new operation <command>nix-store --repair-path</command>
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|     allows corrupted or missing store paths to be repaired by
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|     redownloading them.  <command>nix-store --verify --check-contents
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|     --repair</command> will scan and repair all paths in the Nix
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|     store.  Similarly, <command>nix-env</command>,
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|     <command>nix-build</command>, <command>nix-instantiate</command>
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|     and <command>nix-store --realise</command> have a
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|     <option>--repair</option> flag to detect and fix bad paths by
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|     rebuilding or redownloading them.</para>
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|   </listitem>
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| 
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|   <listitem>
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|     <para>Nix no longer sets the immutable bit on files in the Nix
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|     store.  Instead, the recommended way to guard the Nix store
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|     against accidental modification on Linux is to make it a read-only
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|     bind mount, like this:
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| 
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| <screen>
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| $ mount --bind /nix/store /nix/store
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| $ mount -o remount,ro,bind /nix/store
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| </screen>
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| 
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|     Nix will automatically make <filename>/nix/store</filename>
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|     writable as needed (using a private mount namespace) to allow
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|     modifications.</para>
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|   </listitem>
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| 
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|   <listitem>
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|     <para>Store optimisation (replacing identical files in the store
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|     with hard links) can now be done automatically every time a path
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|     is added to the store.  This is enabled by setting the
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|     configuration option <literal>auto-optimise-store</literal> to
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|     <literal>true</literal> (disabled by default).</para>
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|   </listitem>
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| 
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|   <listitem>
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|     <para>Nix now supports <command>xz</command> compression for NARs
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|     in addition to <command>bzip2</command>.  It compresses about 30%
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|     better on typical archives and decompresses about twice as
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|     fast.</para>
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|   </listitem>
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| 
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|   <listitem>
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|     <para>Basic Nix expression evaluation profiling: setting the
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|     environment variable <envar>NIX_COUNT_CALLS</envar> to
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|     <literal>1</literal> will cause Nix to print how many times each
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|     primop or function was executed.</para>
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|   </listitem>
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| 
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|   <listitem>
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|     <para>New primops: <varname>concatLists</varname>,
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|     <varname>elem</varname>, <varname>elemAt</varname> and
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|     <varname>filter</varname>.</para>
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|   </listitem>
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| 
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|   <listitem>
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|     <para>The command <command>nix-copy-closure</command> has a new
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|     flag <option>--use-substitutes</option> (<option>-s</option>) to
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|     download missing paths on the target machine using the substitute
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|     mechanism.</para>
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|   </listitem>
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| 
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|   <listitem>
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|     <para>The command <command>nix-worker</command> has been renamed
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|     to <command>nix-daemon</command>.  Support for running the Nix
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|     worker in “slave” mode has been removed.</para>
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|   </listitem>
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| 
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|   <listitem>
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|     <para>The <option>--help</option> flag of every Nix command now
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|     invokes <command>man</command>.</para>
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|   </listitem>
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| 
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|   <listitem>
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|     <para>Chroot builds are now supported on systemd machines.</para>
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|   </listitem>
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| 
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| </itemizedlist>
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| 
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| <para>This release has contributions from Eelco Dolstra, Florian
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| Friesdorf, Mats Erik Andersson and Shea Levy.</para>
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| 
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| </section>
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| 
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| 
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| <!--==================================================================-->
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| 
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| <section xml:id="ssec-relnotes-1.1"><title>Release 1.1 (July 18, 2012)</title>
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| 
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| <para>This release has the following improvements:</para>
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| 
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| <itemizedlist>
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| 
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|   <listitem>
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|     <para>On Linux, when doing a chroot build, Nix now uses various
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|     namespace features provided by the Linux kernel to improve
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|     build isolation.  Namely:
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|     <itemizedlist>
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|       <listitem><para>The private network namespace ensures that
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|       builders cannot talk to the outside world (or vice versa): each
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|       build only sees a private loopback interface.  This also means
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|       that two concurrent builds can listen on the same port (e.g. as
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|       part of a test) without conflicting with each
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|       other.</para></listitem>
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|       <listitem><para>The PID namespace causes each build to start as
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|       PID 1.  Processes outside of the chroot are not visible to those
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|       on the inside.  On the other hand, processes inside the chroot
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|       <emphasis>are</emphasis> visible from the outside (though with
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|       different PIDs).</para></listitem>
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|       <listitem><para>The IPC namespace prevents the builder from
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|       communicating with outside processes using SysV IPC mechanisms
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|       (shared memory, message queues, semaphores).  It also ensures
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|       that all IPC objects are destroyed when the builder
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|       exits.</para></listitem>
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|       <listitem><para>The UTS namespace ensures that builders see a
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|       hostname of <literal>localhost</literal> rather than the actual
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|       hostname.</para></listitem>
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|       <listitem><para>The private mount namespace was already used by
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|       Nix to ensure that the bind-mounts used to set up the chroot are
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|       cleaned up automatically.</para></listitem>
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|     </itemizedlist>
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|     </para>
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|   </listitem>
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| 
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|   <listitem>
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|     <para>Build logs are now compressed using
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|     <command>bzip2</command>.  The command <command>nix-store
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|     -l</command> decompresses them on the fly.  This can be disabled
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|     by setting the option <literal>build-compress-log</literal> to
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|     <literal>false</literal>.</para>
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|   </listitem>
 | ||
| 
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|   <listitem>
 | ||
|     <para>The creation of build logs in
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|     <filename>/nix/var/log/nix/drvs</filename> can be disabled by
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|     setting the new option <literal>build-keep-log</literal> to
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|     <literal>false</literal>.  This is useful, for instance, for Hydra
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|     build machines.</para>
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|   </listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>Nix now reserves some space in
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|     <filename>/nix/var/nix/db/reserved</filename> to ensure that the
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|     garbage collector can run successfully if the disk is full.  This
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|     is necessary because SQLite transactions fail if the disk is
 | ||
|     full.</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>Added a basic <function>fetchurl</function> function.  This
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|     is not intended to replace the <function>fetchurl</function> in
 | ||
|     Nixpkgs, but is useful for bootstrapping; e.g., it will allow us
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|     to get rid of the bootstrap binaries in the Nixpkgs source tree
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|     and download them instead.  You can use it by doing
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|     <literal>import <nix/fetchurl.nix> { url =
 | ||
|     <replaceable>url</replaceable>; sha256 =
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|     "<replaceable>hash</replaceable>"; }</literal>. (Shea Levy)</para>
 | ||
|   </listitem>
 | ||
| 
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|   <listitem>
 | ||
|     <para>Improved RPM spec file. (Michel Alexandre Salim)</para>
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|   </listitem>
 | ||
| 
 | ||
|   <listitem>
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|     <para>Support for on-demand socket-based activation in the Nix
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|     daemon with <command>systemd</command>.</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem>
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|     <para>Added a manpage for
 | ||
|     <citerefentry><refentrytitle>nix.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem>
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|     <para>When using the Nix daemon, the <option>-s</option> flag in
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|     <command>nix-env -qa</command> is now much faster.</para>
 | ||
|   </listitem>
 | ||
|     
 | ||
| </itemizedlist>
 | ||
| 
 | ||
| </section>
 | ||
| 
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| 
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| <!--==================================================================-->
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| 
 | ||
| <section xml:id="ssec-relnotes-1.0"><title>Release 1.0 (May 11, 2012)</title>
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| 
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| <para>There have been numerous improvements and bug fixes since the
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| previous release.  Here are the most significant:</para>
 | ||
| 
 | ||
| <itemizedlist>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>Nix can now optionally use the Boehm garbage collector.
 | ||
|     This significantly reduces the Nix evaluator’s memory footprint,
 | ||
|     especially when evaluating large NixOS system configurations.  It
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|     can be enabled using the <option>--enable-gc</option> configure
 | ||
|     option.</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>Nix now uses SQLite for its database.  This is faster and
 | ||
|     more flexible than the old <emphasis>ad hoc</emphasis> format.
 | ||
|     SQLite is also used to cache the manifests in
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|     <filename>/nix/var/nix/manifests</filename>, resulting in a
 | ||
|     significant speedup.</para>
 | ||
|   </listitem>
 | ||
|     
 | ||
|   <listitem>
 | ||
|     <para>Nix now has an search path for expressions.  The search path
 | ||
|     is set using the environment variable <envar>NIX_PATH</envar> and
 | ||
|     the <option>-I</option> command line option.  In Nix expressions,
 | ||
|     paths between angle brackets are used to specify files that must
 | ||
|     be looked up in the search path.  For instance, the expression
 | ||
|     <literal><nixpkgs/default.nix></literal> looks for a file
 | ||
|     <filename>nixpkgs/default.nix</filename> relative to every element
 | ||
|     in the search path.</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>The new command <command>nix-build --run-env</command>
 | ||
|     builds all dependencies of a derivation, then starts a shell in an
 | ||
|     environment containing all variables from the derivation.  This is
 | ||
|     useful for reproducing the environment of a derivation for
 | ||
|     development.</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>The new command <command>nix-store --verify-path</command>
 | ||
|     verifies that the contents of a store path have not
 | ||
|     changed.</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>The new command <command>nix-store --print-env</command>
 | ||
|     prints out the environment of a derivation in a format that can be
 | ||
|     evaluated by a shell.</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>Attribute names can now be arbitrary strings.  For instance,
 | ||
|     you can write <literal>{ "foo-1.2" = …; "bla bla" = …; }."bla
 | ||
|     bla"</literal>.</para>
 | ||
|   </listitem>
 | ||
|     
 | ||
|   <listitem>
 | ||
|     <para>Attribute selection can now provide a default value using
 | ||
|     the <literal>or</literal> operator.  For instance, the expression
 | ||
|     <literal>x.y.z or e</literal> evaluates to the attribute
 | ||
|     <literal>x.y.z</literal> if it exists, and <literal>e</literal>
 | ||
|     otherwise.</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>The right-hand side of the <literal>?</literal> operator can
 | ||
|     now be an attribute path, e.g., <literal>attrs ?
 | ||
|     a.b.c</literal>.</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>On Linux, Nix will now make files in the Nix store immutable
 | ||
|     on filesystems that support it.  This prevents accidental
 | ||
|     modification of files in the store by the root user.</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>Nix has preliminary support for derivations with multiple
 | ||
|     outputs.  This is useful because it allows parts of a package to
 | ||
|     be deployed and garbage-collected separately.  For instance,
 | ||
|     development parts of a package such as header files or static
 | ||
|     libraries would typically not be part of the closure of an
 | ||
|     application, resulting in reduced disk usage and installation
 | ||
|     time.</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>The Nix store garbage collector is faster and holds the
 | ||
|     global lock for a shorter amount of time.</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>The option <option>--timeout</option> (corresponding to the
 | ||
|     configuration setting <literal>build-timeout</literal>) allows you
 | ||
|     to set an absolute timeout on builds — if a build runs for more than
 | ||
|     the given number of seconds, it is terminated.  This is useful for
 | ||
|     recovering automatically from builds that are stuck in an infinite
 | ||
|     loop but keep producing output, and for which
 | ||
|     <literal>--max-silent-time</literal> is ineffective.</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>Nix development has moved to GitHub (<link
 | ||
|     xlink:href="https://github.com/NixOS/nix" />).</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
| </itemizedlist>
 | ||
| 
 | ||
| </section>
 | ||
| 
 | ||
| 
 | ||
| <!--==================================================================-->
 | ||
| 
 | ||
| <section xml:id="ssec-relnotes-0.16"><title>Release 0.16 (August 17, 2010)</title>
 | ||
| 
 | ||
| <para>This release has the following improvements:</para>
 | ||
| 
 | ||
| <itemizedlist>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>The Nix expression evaluator is now much faster in most
 | ||
|     cases: typically, <link
 | ||
|     xlink:href="http://www.mail-archive.com/nix-dev@cs.uu.nl/msg04113.html">3
 | ||
|     to 8 times compared to the old implementation</link>.  It also
 | ||
|     uses less memory.  It no longer depends on the ATerm
 | ||
|     library.</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>
 | ||
|       Support for configurable parallelism inside builders.  Build
 | ||
|       scripts have always had the ability to perform multiple build
 | ||
|       actions in parallel (for instance, by running <command>make -j
 | ||
|       2</command>), but this was not desirable because the number of
 | ||
|       actions to be performed in parallel was not configurable.  Nix
 | ||
|       now has an option <option>--cores
 | ||
|       <replaceable>N</replaceable></option> as well as a configuration
 | ||
|       setting <varname>build-cores =
 | ||
|       <replaceable>N</replaceable></varname> that causes the
 | ||
|       environment variable <envar>NIX_BUILD_CORES</envar> to be set to
 | ||
|       <replaceable>N</replaceable> when the builder is invoked.  The
 | ||
|       builder can use this at its discretion to perform a parallel
 | ||
|       build, e.g., by calling <command>make -j
 | ||
|       <replaceable>N</replaceable></command>.  In Nixpkgs, this can be
 | ||
|       enabled on a per-package basis by setting the derivation
 | ||
|       attribute <varname>enableParallelBuilding</varname> to
 | ||
|       <literal>true</literal>.
 | ||
|     </para>
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para><command>nix-store -q</command> now supports XML output
 | ||
|     through the <option>--xml</option> flag.</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>Several bug fixes.</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
| </itemizedlist>
 | ||
| 
 | ||
| </section>
 | ||
| 
 | ||
| 
 | ||
| <!--==================================================================-->
 | ||
| 
 | ||
| <section xml:id="ssec-relnotes-0.15"><title>Release 0.15 (March 17, 2010)</title>
 | ||
| 
 | ||
| <para>This is a bug-fix release.  Among other things, it fixes
 | ||
| building on Mac OS X (Snow Leopard), and improves the contents of
 | ||
| <filename>/etc/passwd</filename> and <filename>/etc/group</filename>
 | ||
| in <literal>chroot</literal> builds.</para>
 | ||
| 
 | ||
| </section>
 | ||
| 
 | ||
| 
 | ||
| <!--==================================================================-->
 | ||
| 
 | ||
| <section xml:id="ssec-relnotes-0.14"><title>Release 0.14 (February 4, 2010)</title>
 | ||
| 
 | ||
| <para>This release has the following improvements:</para>
 | ||
| 
 | ||
| <itemizedlist>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>The garbage collector now starts deleting garbage much
 | ||
|     faster than before.  It no longer determines liveness of all paths
 | ||
|     in the store, but does so on demand.</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>Added a new operation, <command>nix-store --query
 | ||
|     --roots</command>, that shows the garbage collector roots that
 | ||
|     directly or indirectly point to the given store paths.</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>Removed support for converting Berkeley DB-based Nix
 | ||
|     databases to the new schema.</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>Removed the <option>--use-atime</option> and
 | ||
|     <option>--max-atime</option> garbage collector options.  They were
 | ||
|     not very useful in practice.</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>On Windows, Nix now requires Cygwin 1.7.x.</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>A few bug fixes.</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
| </itemizedlist>
 | ||
| 
 | ||
| </section>
 | ||
| 
 | ||
| 
 | ||
| <!--==================================================================-->
 | ||
| 
 | ||
| <section xml:id="ssec-relnotes-0.13"><title>Release 0.13 (November 5,
 | ||
| 2009)</title>
 | ||
| 
 | ||
| <para>This is primarily a bug fix release.  It has some new
 | ||
| features:</para>
 | ||
| 
 | ||
| <itemizedlist>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>Syntactic sugar for writing nested attribute sets.  Instead of
 | ||
| 
 | ||
| <programlisting>
 | ||
| {
 | ||
|   foo = {
 | ||
|     bar = 123;
 | ||
|     xyzzy = true;
 | ||
|   };
 | ||
|   a = { b = { c = "d"; }; };
 | ||
| }
 | ||
| </programlisting>
 | ||
| 
 | ||
|     you can write
 | ||
| 
 | ||
| <programlisting>
 | ||
| {
 | ||
|   foo.bar = 123;
 | ||
|   foo.xyzzy = true;
 | ||
|   a.b.c = "d";
 | ||
| }
 | ||
| </programlisting>
 | ||
| 
 | ||
|     This is useful, for instance, in NixOS configuration files.</para>
 | ||
|     
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>Support for Nix channels generated by Hydra, the Nix-based
 | ||
|     continuous build system.  (Hydra generates NAR archives on the
 | ||
|     fly, so the size and hash of these archives isn’t known in
 | ||
|     advance.)</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>Support <literal>i686-linux</literal> builds directly on
 | ||
|     <literal>x86_64-linux</literal> Nix installations.  This is
 | ||
|     implemented using the <function>personality()</function> syscall,
 | ||
|     which causes <command>uname</command> to return
 | ||
|     <literal>i686</literal> in child processes.</para>
 | ||
|   </listitem>
 | ||
|   
 | ||
|   <listitem>
 | ||
|     <para>Various improvements to the <literal>chroot</literal>
 | ||
|     support.  Building in a <literal>chroot</literal> works quite well
 | ||
|     now.</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>Nix no longer blocks if it tries to build a path and another
 | ||
|     process is already building the same path.  Instead it tries to
 | ||
|     build another buildable path first.  This improves
 | ||
|     parallelism.</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>Support for large (> 4 GiB) files in NAR archives.</para>
 | ||
|   </listitem>
 | ||
|     
 | ||
|   <listitem>
 | ||
|     <para>Various (performance) improvements to the remote build
 | ||
|     mechanism.</para>
 | ||
|   </listitem>
 | ||
|     
 | ||
|   <listitem>
 | ||
|     <para>New primops: <varname>builtins.addErrorContext</varname> (to
 | ||
|     add a string to stack traces — useful for debugging),
 | ||
|     <varname>builtins.isBool</varname>,
 | ||
|     <varname>builtins.isString</varname>,
 | ||
|     <varname>builtins.isInt</varname>,
 | ||
|     <varname>builtins.intersectAttrs</varname>.</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>OpenSolaris support (Sander van der Burg).</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>Stack traces are no longer displayed unless the
 | ||
|     <option>--show-trace</option> option is used.</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>The scoping rules for <literal>inherit
 | ||
|     (<replaceable>e</replaceable>) ...</literal> in recursive
 | ||
|     attribute sets have changed.  The expression
 | ||
|     <replaceable>e</replaceable> can now refer to the attributes
 | ||
|     defined in the containing set.</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
| </itemizedlist>
 | ||
| 
 | ||
| </section>
 | ||
| 
 | ||
| 
 | ||
| <!--==================================================================-->
 | ||
| 
 | ||
| <section xml:id="ssec-relnotes-0.12"><title>Release 0.12 (November 20,
 | ||
| 2008)</title>
 | ||
| 
 | ||
| <itemizedlist>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>Nix no longer uses Berkeley DB to store Nix store metadata.
 | ||
|     The principal advantages of the new storage scheme are: it works
 | ||
|     properly over decent implementations of NFS (allowing Nix stores
 | ||
|     to be shared between multiple machines); no recovery is needed
 | ||
|     when a Nix process crashes; no write access is needed for
 | ||
|     read-only operations; no more running out of Berkeley DB locks on
 | ||
|     certain operations.</para>
 | ||
| 
 | ||
|     <para>You still need to compile Nix with Berkeley DB support if
 | ||
|     you want Nix to automatically convert your old Nix store to the
 | ||
|     new schema.  If you don’t need this, you can build Nix with the
 | ||
|     <filename>configure</filename> option
 | ||
|     <option>--disable-old-db-compat</option>.</para>
 | ||
| 
 | ||
|     <para>After the automatic conversion to the new schema, you can
 | ||
|     delete the old Berkeley DB files:
 | ||
| 
 | ||
|     <screen>
 | ||
| $ cd /nix/var/nix/db
 | ||
| $ rm __db* log.* derivers references referrers reserved validpaths DB_CONFIG</screen>
 | ||
| 
 | ||
|     The new metadata is stored in the directories
 | ||
|     <filename>/nix/var/nix/db/info</filename> and
 | ||
|     <filename>/nix/var/nix/db/referrer</filename>.  Though the
 | ||
|     metadata is stored in human-readable plain-text files, they are
 | ||
|     not intended to be human-editable, as Nix is rather strict about
 | ||
|     the format.</para>
 | ||
| 
 | ||
|     <para>The new storage schema may or may not require less disk
 | ||
|     space than the Berkeley DB environment, mostly depending on the
 | ||
|     cluster size of your file system.  With 1 KiB clusters (which
 | ||
|     seems to be the <literal>ext3</literal> default nowadays) it
 | ||
|     usually takes up much less space.</para>
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem><para>There is a new substituter that copies paths
 | ||
|   directly from other (remote) Nix stores mounted somewhere in the
 | ||
|   filesystem.  For instance, you can speed up an installation by
 | ||
|   mounting some remote Nix store that already has the packages in
 | ||
|   question via NFS or <literal>sshfs</literal>.  The environment
 | ||
|   variable <envar>NIX_OTHER_STORES</envar> specifies the locations of
 | ||
|   the remote Nix directories,
 | ||
|   e.g. <literal>/mnt/remote-fs/nix</literal>.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>New <command>nix-store</command> operations
 | ||
|   <option>--dump-db</option> and <option>--load-db</option> to dump
 | ||
|   and reload the Nix database.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>The garbage collector has a number of new options to
 | ||
|   allow only some of the garbage to be deleted.  The option
 | ||
|   <option>--max-freed <replaceable>N</replaceable></option> tells the
 | ||
|   collector to stop after at least <replaceable>N</replaceable> bytes
 | ||
|   have been deleted.  The option <option>--max-links
 | ||
|   <replaceable>N</replaceable></option> tells it to stop after the
 | ||
|   link count on <filename>/nix/store</filename> has dropped below
 | ||
|   <replaceable>N</replaceable>.  This is useful for very large Nix
 | ||
|   stores on filesystems with a 32000 subdirectories limit (like
 | ||
|   <literal>ext3</literal>).  The option <option>--use-atime</option>
 | ||
|   causes store paths to be deleted in order of ascending last access
 | ||
|   time.  This allows non-recently used stuff to be deleted.  The
 | ||
|   option <option>--max-atime <replaceable>time</replaceable></option>
 | ||
|   specifies an upper limit to the last accessed time of paths that may
 | ||
|   be deleted.  For instance,
 | ||
| 
 | ||
|     <screen>
 | ||
|     $ nix-store --gc -v --max-atime $(date +%s -d "2 months ago")</screen>
 | ||
| 
 | ||
|   deletes everything that hasn’t been accessed in two months.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para><command>nix-env</command> now uses optimistic
 | ||
|   profile locking when performing an operation like installing or
 | ||
|   upgrading, instead of setting an exclusive lock on the profile.
 | ||
|   This allows multiple <command>nix-env -i / -u / -e</command>
 | ||
|   operations on the same profile in parallel.  If a
 | ||
|   <command>nix-env</command> operation sees at the end that the profile
 | ||
|   was changed in the meantime by another process, it will just
 | ||
|   restart.  This is generally cheap because the build results are
 | ||
|   still in the Nix store.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>The option <option>--dry-run</option> is now
 | ||
|   supported by <command>nix-store -r</command> and
 | ||
|   <command>nix-build</command>.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>The information previously shown by
 | ||
|   <option>--dry-run</option> (i.e., which derivations will be built
 | ||
|   and which paths will be substituted) is now always shown by
 | ||
|   <command>nix-env</command>, <command>nix-store -r</command> and
 | ||
|   <command>nix-build</command>.  The total download size of
 | ||
|   substitutable paths is now also shown.  For instance, a build will
 | ||
|   show something like
 | ||
| 
 | ||
|     <screen>
 | ||
| the following derivations will be built:
 | ||
|   /nix/store/129sbxnk5n466zg6r1qmq1xjv9zymyy7-activate-configuration.sh.drv
 | ||
|   /nix/store/7mzy971rdm8l566ch8hgxaf89x7lr7ik-upstart-jobs.drv
 | ||
|   ...
 | ||
| the following paths will be downloaded/copied (30.02 MiB):
 | ||
|   /nix/store/4m8pvgy2dcjgppf5b4cj5l6wyshjhalj-samba-3.2.4
 | ||
|   /nix/store/7h1kwcj29ip8vk26rhmx6bfjraxp0g4l-libunwind-0.98.6
 | ||
|   ...</screen>      
 | ||
|   
 | ||
|   </para></listitem>
 | ||
| 
 | ||
|   <listitem><para>Language features:
 | ||
| 
 | ||
|     <itemizedlist>
 | ||
| 
 | ||
|       <listitem><para>@-patterns as in Haskell.  For instance, in a
 | ||
|       function definition
 | ||
| 
 | ||
|       <programlisting>f = args @ {x, y, z}: <replaceable>...</replaceable>;</programlisting>
 | ||
| 
 | ||
|       <varname>args</varname> refers to the argument as a whole, which
 | ||
|       is further pattern-matched against the attribute set pattern
 | ||
|       <literal>{x, y, z}</literal>.</para></listitem>
 | ||
| 
 | ||
|       <listitem><para>“<literal>...</literal>” (ellipsis) patterns.
 | ||
|       An attribute set pattern can now say <literal>...</literal>  at
 | ||
|       the end of the attribute name list to specify that the function
 | ||
|       takes <emphasis>at least</emphasis> the listed attributes, while
 | ||
|       ignoring additional attributes.  For instance,
 | ||
| 
 | ||
|       <programlisting>{stdenv, fetchurl, fuse, ...}: <replaceable>...</replaceable></programlisting>
 | ||
| 
 | ||
|       defines a function that accepts any attribute set that includes
 | ||
|       at least the three listed attributes.</para></listitem>
 | ||
| 
 | ||
|       <listitem><para>New primops:
 | ||
|       <varname>builtins.parseDrvName</varname> (split a package name
 | ||
|       string like <literal>"nix-0.12pre12876"</literal> into its name
 | ||
|       and version components, e.g. <literal>"nix"</literal> and
 | ||
|       <literal>"0.12pre12876"</literal>),
 | ||
|       <varname>builtins.compareVersions</varname> (compare two version
 | ||
|       strings using the same algorithm that <command>nix-env</command>
 | ||
|       uses), <varname>builtins.length</varname> (efficiently compute
 | ||
|       the length of a list), <varname>builtins.mul</varname> (integer
 | ||
|       multiplication), <varname>builtins.div</varname> (integer
 | ||
|       division).
 | ||
|       <!-- <varname>builtins.genericClosure</varname> -->
 | ||
|       </para></listitem>
 | ||
|       
 | ||
|     </itemizedlist>
 | ||
| 
 | ||
|   </para></listitem>
 | ||
| 
 | ||
|   <listitem><para><command>nix-prefetch-url</command> now supports
 | ||
|   <literal>mirror://</literal> URLs, provided that the environment
 | ||
|   variable <envar>NIXPKGS_ALL</envar> points at a Nixpkgs
 | ||
|   tree.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>Removed the commands
 | ||
|   <command>nix-pack-closure</command> and
 | ||
|   <command>nix-unpack-closure</command>.   You can do almost the same
 | ||
|   thing but much more efficiently by doing <literal>nix-store --export
 | ||
|   $(nix-store -qR <replaceable>paths</replaceable>) > closure</literal> and
 | ||
|   <literal>nix-store --import <
 | ||
|   closure</literal>.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>Lots of bug fixes, including a big performance bug in
 | ||
|   the handling of <literal>with</literal>-expressions.</para></listitem>
 | ||
| 
 | ||
| </itemizedlist>
 | ||
| 
 | ||
| </section>
 | ||
| 
 | ||
| 
 | ||
| <!--==================================================================-->
 | ||
| 
 | ||
| <section xml:id="ssec-relnotes-0.11"><title>Release 0.11 (December 31,
 | ||
| 2007)</title>
 | ||
| 
 | ||
| <para>Nix 0.11 has many improvements over the previous stable release.
 | ||
| The most important improvement is secure multi-user support.  It also
 | ||
| features many usability enhancements and language extensions, many of
 | ||
| them prompted by NixOS, the purely functional Linux distribution based
 | ||
| on Nix.  Here is an (incomplete) list:</para>
 | ||
| 
 | ||
| 
 | ||
| <itemizedlist>
 | ||
| 
 | ||
| 
 | ||
|   <listitem><para>Secure multi-user support.  A single Nix store can
 | ||
|   now be shared between multiple (possible untrusted) users.  This is
 | ||
|   an important feature for NixOS, where it allows non-root users to
 | ||
|   install software.  The old setuid method for sharing a store between
 | ||
|   multiple users has been removed.  Details for setting up a
 | ||
|   multi-user store can be found in the manual.</para></listitem>
 | ||
| 
 | ||
| 
 | ||
|   <listitem><para>The new command <command>nix-copy-closure</command>
 | ||
|   gives you an easy and efficient way to exchange software between
 | ||
|   machines.  It copies the missing parts of the closure of a set of
 | ||
|   store path to or from a remote machine via
 | ||
|   <command>ssh</command>.</para></listitem>
 | ||
| 
 | ||
| 
 | ||
|   <listitem><para>A new kind of string literal: strings between double
 | ||
|   single-quotes (<literal>''</literal>) have indentation
 | ||
|   “intelligently” removed.  This allows large strings (such as shell
 | ||
|   scripts or configuration file fragments in NixOS) to cleanly follow
 | ||
|   the indentation of the surrounding expression.  It also requires
 | ||
|   much less escaping, since <literal>''</literal> is less common in
 | ||
|   most languages than <literal>"</literal>.</para></listitem>
 | ||
| 
 | ||
| 
 | ||
|   <listitem><para><command>nix-env</command> <option>--set</option>
 | ||
|   modifies the current generation of a profile so that it contains
 | ||
|   exactly the specified derivation, and nothing else.  For example,
 | ||
|   <literal>nix-env -p /nix/var/nix/profiles/browser --set
 | ||
|   firefox</literal> lets the profile named
 | ||
|   <filename>browser</filename> contain just Firefox.</para></listitem>
 | ||
|   
 | ||
| 
 | ||
|   <listitem><para><command>nix-env</command> now maintains
 | ||
|   meta-information about installed packages in profiles.  The
 | ||
|   meta-information is the contents of the <varname>meta</varname>
 | ||
|   attribute of derivations, such as <varname>description</varname> or
 | ||
|   <varname>homepage</varname>.  The command <literal>nix-env -q --xml
 | ||
|   --meta</literal> shows all meta-information.</para></listitem>
 | ||
| 
 | ||
|   
 | ||
|   <listitem><para><command>nix-env</command> now uses the
 | ||
|   <varname>meta.priority</varname> attribute of derivations to resolve
 | ||
|   filename collisions between packages.  Lower priority values denote
 | ||
|   a higher priority.  For instance, the GCC wrapper package and the
 | ||
|   Binutils package in Nixpkgs both have a file
 | ||
|   <filename>bin/ld</filename>, so previously if you tried to install
 | ||
|   both you would get a collision.  Now, on the other hand, the GCC
 | ||
|   wrapper declares a higher priority than Binutils, so the former’s
 | ||
|   <filename>bin/ld</filename> is symlinked in the user
 | ||
|   environment.</para></listitem>
 | ||
| 
 | ||
| 
 | ||
|   <listitem><para><command>nix-env -i / -u</command>: instead of
 | ||
|   breaking package ties by version, break them by priority and version
 | ||
|   number.  That is, if there are multiple packages with the same name,
 | ||
|   then pick the package with the highest priority, and only use the
 | ||
|   version if there are multiple packages with the same
 | ||
|   priority.</para>
 | ||
| 
 | ||
|   <para>This makes it possible to mark specific versions/variant in
 | ||
|   Nixpkgs more or less desirable than others.  A typical example would
 | ||
|   be a beta version of some package (e.g.,
 | ||
|   <literal>gcc-4.2.0rc1</literal>) which should not be installed even
 | ||
|   though it is the highest version, except when it is explicitly
 | ||
|   selected (e.g., <literal>nix-env -i
 | ||
|   gcc-4.2.0rc1</literal>).</para></listitem>
 | ||
| 
 | ||
| 
 | ||
|   <listitem><para><command>nix-env --set-flag</command> allows meta
 | ||
|   attributes of installed packages to be modified.  There are several
 | ||
|   attributes that can be usefully modified, because they affect the
 | ||
|   behaviour of <command>nix-env</command> or the user environment
 | ||
|   build script:
 | ||
| 
 | ||
|     <itemizedlist>
 | ||
| 
 | ||
|       <listitem><para><varname>meta.priority</varname> can be changed
 | ||
|       to resolve filename clashes (see above).</para></listitem>
 | ||
| 
 | ||
|       <listitem><para><varname>meta.keep</varname> can be set to
 | ||
|       <literal>true</literal> to prevent the package from being
 | ||
|       upgraded or replaced.  Useful if you want to hang on to an older
 | ||
|       version of a package.</para></listitem>
 | ||
| 
 | ||
|       <listitem><para><varname>meta.active</varname> can be set to
 | ||
|       <literal>false</literal> to “disable” the package.  That is, no
 | ||
|       symlinks will be generated to the files of the package, but it
 | ||
|       remains part of the profile (so it won’t be garbage-collected).
 | ||
|       Set it back to <literal>true</literal> to re-enable the
 | ||
|       package.</para></listitem>
 | ||
| 
 | ||
|     </itemizedlist>
 | ||
| 
 | ||
|   </para></listitem>
 | ||
| 
 | ||
|   
 | ||
|   <listitem><para><command>nix-env -q</command> now has a flag
 | ||
|   <option>--prebuilt-only</option> (<option>-b</option>) that causes
 | ||
|   <command>nix-env</command> to show only those derivations whose
 | ||
|   output is already in the Nix store or that can be substituted (i.e.,
 | ||
|   downloaded from somewhere).  In other words, it shows the packages
 | ||
|   that can be installed “quickly”, i.e., don’t need to be built from
 | ||
|   source.  The <option>-b</option> flag is also available in
 | ||
|   <command>nix-env -i</command> and <command>nix-env -u</command> to
 | ||
|   filter out derivations for which no pre-built binary is
 | ||
|   available.</para></listitem>
 | ||
|   
 | ||
| 
 | ||
|   <listitem><para>The new option <option>--argstr</option> (in
 | ||
|   <command>nix-env</command>, <command>nix-instantiate</command> and
 | ||
|   <command>nix-build</command>) is like <option>--arg</option>, except
 | ||
|   that the value is a string.  For example, <literal>--argstr system
 | ||
|   i686-linux</literal> is equivalent to <literal>--arg system
 | ||
|   \"i686-linux\"</literal> (note that <option>--argstr</option>
 | ||
|   prevents annoying quoting around shell arguments).</para></listitem>
 | ||
| 
 | ||
| 
 | ||
|   <listitem><para><command>nix-store</command> has a new operation
 | ||
|   <option>--read-log</option> (<option>-l</option>)
 | ||
|   <parameter>paths</parameter> that shows the build log of the given
 | ||
|   paths.</para></listitem>
 | ||
| 
 | ||
|   
 | ||
|   <!--
 | ||
|   <listitem><para>TODO: semantic cleanups of string concatenation
 | ||
|   etc. (mostly in r6740).</para></listitem>
 | ||
|   -->
 | ||
| 
 | ||
| 
 | ||
|   <listitem><para>Nix now uses Berkeley DB 4.5.  The database is
 | ||
|   upgraded automatically, but you should be careful not to use old
 | ||
|   versions of Nix that still use Berkeley DB 4.4.</para></listitem>
 | ||
| 
 | ||
| 
 | ||
|   <!-- foo
 | ||
|   <listitem><para>TODO: option <option>- -reregister</option> in
 | ||
|   <command>nix-store - -register-validity</command>.</para></listitem>
 | ||
|   -->
 | ||
| 
 | ||
| 
 | ||
|   <listitem><para>The option <option>--max-silent-time</option>
 | ||
|   (corresponding to the configuration setting
 | ||
|   <literal>build-max-silent-time</literal>) allows you to set a
 | ||
|   timeout on builds — if a build produces no output on
 | ||
|   <literal>stdout</literal> or <literal>stderr</literal> for the given
 | ||
|   number of seconds, it is terminated.  This is useful for recovering
 | ||
|   automatically from builds that are stuck in an infinite
 | ||
|   loop.</para></listitem>
 | ||
| 
 | ||
| 
 | ||
|   <listitem><para><command>nix-channel</command>: each subscribed
 | ||
|   channel is its own attribute in the top-level expression generated
 | ||
|   for the channel.  This allows disambiguation (e.g. <literal>nix-env
 | ||
|   -i -A nixpkgs_unstable.firefox</literal>).</para></listitem>
 | ||
| 
 | ||
| 
 | ||
|   <listitem><para>The substitutes table has been removed from the
 | ||
|   database.  This makes operations such as <command>nix-pull</command>
 | ||
|   and <command>nix-channel --update</command> much, much
 | ||
|   faster.</para></listitem>
 | ||
| 
 | ||
| 
 | ||
|   <listitem><para><command>nix-pull</command> now supports
 | ||
|   bzip2-compressed manifests.  This speeds up
 | ||
|   channels.</para></listitem>
 | ||
| 
 | ||
| 
 | ||
|   <listitem><para><command>nix-prefetch-url</command> now has a
 | ||
|   limited form of caching.  This is used by
 | ||
|   <command>nix-channel</command> to prevent unnecessary downloads when
 | ||
|   the channel hasn’t changed.</para></listitem>
 | ||
| 
 | ||
| 
 | ||
|   <listitem><para><command>nix-prefetch-url</command> now by default
 | ||
|   computes the SHA-256 hash of the file instead of the MD5 hash.  In
 | ||
|   calls to <function>fetchurl</function> you should pass the
 | ||
|   <literal>sha256</literal> attribute instead of
 | ||
|   <literal>md5</literal>.  You can pass either a hexadecimal or a
 | ||
|   base-32 encoding of the hash.</para></listitem>
 | ||
| 
 | ||
|   
 | ||
|   <listitem><para>Nix can now perform builds in an automatically
 | ||
|   generated “chroot”.  This prevents a builder from accessing stuff
 | ||
|   outside of the Nix store, and thus helps ensure purity.  This is an
 | ||
|   experimental feature.</para></listitem>
 | ||
|   
 | ||
| 
 | ||
|   <listitem><para>The new command <command>nix-store
 | ||
|   --optimise</command> reduces Nix store disk space usage by finding
 | ||
|   identical files in the store and hard-linking them to each other.
 | ||
|   It typically reduces the size of the store by something like
 | ||
|   25-35%.</para></listitem>
 | ||
| 
 | ||
|   
 | ||
|   <listitem><para><filename>~/.nix-defexpr</filename> can now be a
 | ||
|   directory, in which case the Nix expressions in that directory are
 | ||
|   combined into an attribute set, with the file names used as the
 | ||
|   names of the attributes.  The command <command>nix-env
 | ||
|   --import</command> (which set the
 | ||
|   <filename>~/.nix-defexpr</filename> symlink) is
 | ||
|   removed.</para></listitem>
 | ||
| 
 | ||
| 
 | ||
|   <listitem><para>Derivations can specify the new special attribute
 | ||
|   <varname>allowedReferences</varname> to enforce that the references
 | ||
|   in the output of a derivation are a subset of a declared set of
 | ||
|   paths.  For example, if <varname>allowedReferences</varname> is an
 | ||
|   empty list, then the output must not have any references.  This is
 | ||
|   used in NixOS to check that generated files such as initial ramdisks
 | ||
|   for booting Linux don’t have any dependencies.</para></listitem>
 | ||
| 
 | ||
| 
 | ||
|   <listitem><para>The new attribute
 | ||
|   <varname>exportReferencesGraph</varname> allows builders access to
 | ||
|   the references graph of their inputs.  This is used in NixOS for
 | ||
|   tasks such as generating ISO-9660 images that contain a Nix store
 | ||
|   populated with the closure of certain paths.</para></listitem>
 | ||
| 
 | ||
| 
 | ||
|   <listitem><para>Fixed-output derivations (like
 | ||
|   <function>fetchurl</function>) can define the attribute
 | ||
|   <varname>impureEnvVars</varname> to allow external environment
 | ||
|   variables to be passed to builders.  This is used in Nixpkgs to
 | ||
|   support proxy configuration, among other things.</para></listitem>
 | ||
| 
 | ||
| 
 | ||
|   <listitem><para>Several new built-in functions:
 | ||
|   <function>builtins.attrNames</function>,
 | ||
|   <function>builtins.filterSource</function>,
 | ||
|   <function>builtins.isAttrs</function>,
 | ||
|   <function>builtins.isFunction</function>,
 | ||
|   <function>builtins.listToAttrs</function>,
 | ||
|   <function>builtins.stringLength</function>,
 | ||
|   <function>builtins.sub</function>,
 | ||
|   <function>builtins.substring</function>,
 | ||
|   <function>throw</function>,
 | ||
|   <function>builtins.trace</function>,
 | ||
|   <function>builtins.readFile</function>.</para></listitem>
 | ||
| 
 | ||
| 
 | ||
| </itemizedlist>
 | ||
| 
 | ||
| </section>
 | ||
| 
 | ||
| 
 | ||
| 
 | ||
| <!--==================================================================-->
 | ||
| 
 | ||
| <section><title>Release 0.10.1 (October 11, 2006)</title>
 | ||
| 
 | ||
| <para>This release fixes two somewhat obscure bugs that occur when
 | ||
| evaluating Nix expressions that are stored inside the Nix store
 | ||
| (<literal>NIX-67</literal>).  These do not affect most users.</para>
 | ||
| 
 | ||
| </section>
 | ||
| 
 | ||
| 
 | ||
| 
 | ||
| <!--==================================================================-->
 | ||
| 
 | ||
| <section><title>Release 0.10 (October 6, 2006)</title>
 | ||
| 
 | ||
| <note><para>This version of Nix uses Berkeley DB 4.4 instead of 4.3.
 | ||
| The database is upgraded automatically, but you should be careful not
 | ||
| to use old versions of Nix that still use Berkeley DB 4.3.  In
 | ||
| particular, if you use a Nix installed through Nix, you should run
 | ||
| 
 | ||
| <screen>
 | ||
| $ nix-store --clear-substitutes</screen>
 | ||
| 
 | ||
| first.</para></note>
 | ||
| 
 | ||
| <warning><para>Also, the database schema has changed slighted to fix a
 | ||
| performance issue (see below).  When you run any Nix 0.10 command for
 | ||
| the first time, the database will be upgraded automatically.  This is
 | ||
| irreversible.</para></warning>
 | ||
| 
 | ||
| <itemizedlist>
 | ||
| 
 | ||
|   
 | ||
|   <!-- Usability / features -->
 | ||
| 
 | ||
|   
 | ||
|   <listitem><para><command>nix-env</command> usability improvements:
 | ||
| 
 | ||
|     <itemizedlist>
 | ||
| 
 | ||
|       <listitem><para>An option <option>--compare-versions</option>
 | ||
|       (or <option>-c</option>) has been added to <command>nix-env
 | ||
|       --query</command> to allow you to compare installed versions of
 | ||
|       packages to available versions, or vice versa.  An easy way to
 | ||
|       see if you are up to date with what’s in your subscribed
 | ||
|       channels is <literal>nix-env -qc \*</literal>.</para></listitem>
 | ||
| 
 | ||
|       <listitem><para><literal>nix-env --query</literal> now takes as
 | ||
|       arguments a list of package names about which to show
 | ||
|       information, just like <option>--install</option>, etc.: for
 | ||
|       example, <literal>nix-env -q gcc</literal>.  Note that to show
 | ||
|       all derivations, you need to specify
 | ||
|       <literal>\*</literal>.</para></listitem>
 | ||
| 
 | ||
|       <listitem><para><literal>nix-env -i
 | ||
|       <replaceable>pkgname</replaceable></literal> will now install
 | ||
|       the highest available version of
 | ||
|       <replaceable>pkgname</replaceable>, rather than installing all
 | ||
|       available versions (which would probably give collisions)
 | ||
|       (<literal>NIX-31</literal>).</para></listitem>
 | ||
| 
 | ||
|       <listitem><para><literal>nix-env (-i|-u) --dry-run</literal> now
 | ||
|       shows exactly which missing paths will be built or
 | ||
|       substituted.</para></listitem>
 | ||
| 
 | ||
|       <listitem><para><literal>nix-env -qa --description</literal>
 | ||
|       shows human-readable descriptions of packages, provided that
 | ||
|       they have a <literal>meta.description</literal> attribute (which
 | ||
|       most packages in Nixpkgs don’t have yet).</para></listitem>
 | ||
| 
 | ||
|     </itemizedlist>
 | ||
|   
 | ||
|   </para></listitem>
 | ||
|   
 | ||
| 
 | ||
|   <listitem><para>New language features:
 | ||
| 
 | ||
|     <itemizedlist>
 | ||
| 
 | ||
|       <listitem><para>Reference scanning (which happens after each
 | ||
|       build) is much faster and takes a constant amount of
 | ||
|       memory.</para></listitem>
 | ||
| 
 | ||
|       <listitem><para>String interpolation.  Expressions like
 | ||
| 
 | ||
| <programlisting>
 | ||
| "--with-freetype2-library=" + freetype + "/lib"</programlisting>
 | ||
| 
 | ||
|       can now be written as
 | ||
| 
 | ||
| <programlisting>
 | ||
| "--with-freetype2-library=${freetype}/lib"</programlisting>
 | ||
| 
 | ||
|       You can write arbitrary expressions within
 | ||
|       <literal>${<replaceable>...</replaceable>}</literal>, not just
 | ||
|       identifiers.</para></listitem>
 | ||
|       
 | ||
|       <listitem><para>Multi-line string literals.</para></listitem>
 | ||
| 
 | ||
|       <listitem><para>String concatenations can now involve
 | ||
|       derivations, as in the example <code>"--with-freetype2-library="
 | ||
|       + freetype + "/lib"</code>.  This was not previously possible
 | ||
|       because we need to register that a derivation that uses such a
 | ||
|       string is dependent on <literal>freetype</literal>.  The
 | ||
|       evaluator now properly propagates this information.
 | ||
|       Consequently, the subpath operator (<literal>~</literal>) has
 | ||
|       been deprecated.</para></listitem>
 | ||
| 
 | ||
|       <listitem><para>Default values of function arguments can now
 | ||
|       refer to other function arguments; that is, all arguments are in
 | ||
|       scope in the default values
 | ||
|       (<literal>NIX-45</literal>).</para></listitem>
 | ||
| 
 | ||
|       <!--
 | ||
|       <listitem><para>TODO: domain checks (r5895).</para></listitem>
 | ||
|       -->
 | ||
| 
 | ||
|       <listitem><para>Lots of new built-in primitives, such as
 | ||
|       functions for list manipulation and integer arithmetic.  See the
 | ||
|       manual for a complete list.  All primops are now available in
 | ||
|       the set <varname>builtins</varname>, allowing one to test for
 | ||
|       the availability of primop in a backwards-compatible
 | ||
|       way.</para></listitem>
 | ||
| 
 | ||
|       <listitem><para>Real let-expressions: <literal>let x = ...;
 | ||
|       ... z = ...; in ...</literal>.</para></listitem>
 | ||
| 
 | ||
|     </itemizedlist>
 | ||
| 
 | ||
|   </para></listitem>
 | ||
| 
 | ||
| 
 | ||
|   <listitem><para>New commands <command>nix-pack-closure</command> and
 | ||
|   <command>nix-unpack-closure</command> than can be used to easily
 | ||
|   transfer a store path with all its dependencies to another machine.
 | ||
|   Very convenient whenever you have some package on your machine and
 | ||
|   you want to copy it somewhere else.</para></listitem>
 | ||
| 
 | ||
|   
 | ||
|   <listitem><para>XML support:
 | ||
| 
 | ||
|     <itemizedlist>
 | ||
| 
 | ||
|       <listitem><para><literal>nix-env -q --xml</literal> prints the
 | ||
|       installed or available packages in an XML representation for
 | ||
|       easy processing by other tools.</para></listitem>
 | ||
| 
 | ||
|       <listitem><para><literal>nix-instantiate --eval-only
 | ||
|       --xml</literal> prints an XML representation of the resulting
 | ||
|       term.  (The new flag <option>--strict</option> forces ‘deep’
 | ||
|       evaluation of the result, i.e., list elements and attributes are
 | ||
|       evaluated recursively.)</para></listitem>
 | ||
| 
 | ||
|       <listitem><para>In Nix expressions, the primop
 | ||
|       <function>builtins.toXML</function> converts a term to an XML
 | ||
|       representation.  This is primarily useful for passing structured
 | ||
|       information to builders.</para></listitem>
 | ||
| 
 | ||
|     </itemizedlist>
 | ||
| 
 | ||
|   </para></listitem>
 | ||
|   
 | ||
| 
 | ||
|   <listitem><para>You can now unambigously specify which derivation to
 | ||
|   build or install in <command>nix-env</command>,
 | ||
|   <command>nix-instantiate</command> and <command>nix-build</command>
 | ||
|   using the <option>--attr</option> / <option>-A</option> flags, which
 | ||
|   takes an attribute name as argument.  (Unlike symbolic package names
 | ||
|   such as <literal>subversion-1.4.0</literal>, attribute names in an
 | ||
|   attribute set are unique.)  For instance, a quick way to perform a
 | ||
|   test build of a package in Nixpkgs is <literal>nix-build
 | ||
|   pkgs/top-level/all-packages.nix -A
 | ||
|   <replaceable>foo</replaceable></literal>.  <literal>nix-env -q
 | ||
|   --attr</literal> shows the attribute names corresponding to each
 | ||
|   derivation.</para></listitem>
 | ||
|   
 | ||
| 
 | ||
|   <listitem><para>If the top-level Nix expression used by
 | ||
|   <command>nix-env</command>, <command>nix-instantiate</command> or
 | ||
|   <command>nix-build</command> evaluates to a function whose arguments
 | ||
|   all have default values, the function will be called automatically.
 | ||
|   Also, the new command-line switch <option>--arg
 | ||
|   <replaceable>name</replaceable>
 | ||
|   <replaceable>value</replaceable></option> can be used to specify
 | ||
|   function arguments on the command line.</para></listitem>
 | ||
| 
 | ||
|   
 | ||
|   <listitem><para><literal>nix-install-package --url
 | ||
|   <replaceable>URL</replaceable></literal> allows a package to be
 | ||
|   installed directly from the given URL.</para></listitem>
 | ||
| 
 | ||
| 
 | ||
|   <listitem><para>Nix now works behind an HTTP proxy server; just set
 | ||
|   the standard environment variables <envar>http_proxy</envar>,
 | ||
|   <envar>https_proxy</envar>, <envar>ftp_proxy</envar> or
 | ||
|   <envar>all_proxy</envar> appropriately.  Functions such as
 | ||
|   <function>fetchurl</function> in Nixpkgs also respect these
 | ||
|   variables.</para></listitem>
 | ||
| 
 | ||
| 
 | ||
|   <listitem><para><literal>nix-build -o
 | ||
|   <replaceable>symlink</replaceable></literal> allows the symlink to
 | ||
|   the build result to be named something other than
 | ||
|   <literal>result</literal>.</para></listitem>
 | ||
| 
 | ||
| 
 | ||
|   <!-- Stability / performance / etc. -->
 | ||
| 
 | ||
| 
 | ||
|   <listitem><para>Platform support:
 | ||
| 
 | ||
|     <itemizedlist>
 | ||
| 
 | ||
|       <listitem><para>Support for 64-bit platforms, provided a <link
 | ||
|       xlink:href="http://bugzilla.sen.cwi.nl:8080/show_bug.cgi?id=606">suitably
 | ||
|       patched ATerm library</link> is used.  Also, files larger than 2
 | ||
|       GiB are now supported.</para></listitem>
 | ||
| 
 | ||
|       <listitem><para>Added support for Cygwin (Windows,
 | ||
|       <literal>i686-cygwin</literal>), Mac OS X on Intel
 | ||
|       (<literal>i686-darwin</literal>) and Linux on PowerPC
 | ||
|       (<literal>powerpc-linux</literal>).</para></listitem>
 | ||
| 
 | ||
|       <listitem><para>Users of SMP and multicore machines will
 | ||
|       appreciate that the number of builds to be performed in parallel
 | ||
|       can now be specified in the configuration file in the
 | ||
|       <literal>build-max-jobs</literal> setting.</para></listitem>
 | ||
| 
 | ||
|     </itemizedlist>
 | ||
| 
 | ||
|   </para></listitem>
 | ||
| 
 | ||
|   
 | ||
|   <listitem><para>Garbage collector improvements:
 | ||
| 
 | ||
|     <itemizedlist>
 | ||
| 
 | ||
|       <listitem><para>Open files (such as running programs) are now
 | ||
|       used as roots of the garbage collector.  This prevents programs
 | ||
|       that have been uninstalled from being garbage collected while
 | ||
|       they are still running.  The script that detects these
 | ||
|       additional runtime roots
 | ||
|       (<filename>find-runtime-roots.pl</filename>) is inherently
 | ||
|       system-specific, but it should work on Linux and on all
 | ||
|       platforms that have the <command>lsof</command>
 | ||
|       utility.</para></listitem>
 | ||
| 
 | ||
|       <listitem><para><literal>nix-store --gc</literal>
 | ||
|       (a.k.a. <command>nix-collect-garbage</command>) prints out the
 | ||
|       number of bytes freed on standard output.  <literal>nix-store
 | ||
|       --gc --print-dead</literal> shows how many bytes would be freed
 | ||
|       by an actual garbage collection.</para></listitem>
 | ||
| 
 | ||
|       <listitem><para><literal>nix-collect-garbage -d</literal>
 | ||
|       removes all old generations of <emphasis>all</emphasis> profiles
 | ||
|       before calling the actual garbage collector (<literal>nix-store
 | ||
|       --gc</literal>).  This is an easy way to get rid of all old
 | ||
|       packages in the Nix store.</para></listitem>
 | ||
| 
 | ||
|       <listitem><para><command>nix-store</command> now has an
 | ||
|       operation <option>--delete</option> to delete specific paths
 | ||
|       from the Nix store.  It won’t delete reachable (non-garbage)
 | ||
|       paths unless <option>--ignore-liveness</option> is
 | ||
|       specified.</para></listitem>
 | ||
|       
 | ||
|     </itemizedlist>
 | ||
| 
 | ||
|   </para></listitem>
 | ||
| 
 | ||
|   
 | ||
|   <listitem><para>Berkeley DB 4.4’s process registry feature is used
 | ||
|   to recover from crashed Nix processes.</para></listitem>
 | ||
| 
 | ||
|   <!--  <listitem><para>TODO: shared stores.</para></listitem> -->
 | ||
| 
 | ||
|   <listitem><para>A performance issue has been fixed with the
 | ||
|   <literal>referer</literal> table, which stores the inverse of the
 | ||
|   <literal>references</literal> table (i.e., it tells you what store
 | ||
|   paths refer to a given path).  Maintaining this table could take a
 | ||
|   quadratic amount of time, as well as a quadratic amount of Berkeley
 | ||
|   DB log file space (in particular when running the garbage collector)
 | ||
|   (<literal>NIX-23</literal>).</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>Nix now catches the <literal>TERM</literal> and
 | ||
|   <literal>HUP</literal> signals in addition to the
 | ||
|   <literal>INT</literal> signal.  So you can now do a <literal>killall
 | ||
|   nix-store</literal> without triggering a database
 | ||
|   recovery.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para><command>bsdiff</command> updated to version
 | ||
|   4.3.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>Substantial performance improvements in expression
 | ||
|   evaluation and <literal>nix-env -qa</literal>, all thanks to <link
 | ||
|   xlink:href="http://valgrind.org/">Valgrind</link>.  Memory use has
 | ||
|   been reduced by a factor 8 or so.  Big speedup by memoisation of
 | ||
|   path hashing.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>Lots of bug fixes, notably:
 | ||
| 
 | ||
|     <itemizedlist>
 | ||
| 
 | ||
|       <listitem><para>Make sure that the garbage collector can run
 | ||
|       succesfully when the disk is full
 | ||
|       (<literal>NIX-18</literal>).</para></listitem>
 | ||
| 
 | ||
|       <listitem><para><command>nix-env</command> now locks the profile
 | ||
|       to prevent races between concurrent <command>nix-env</command>
 | ||
|       operations on the same profile
 | ||
|       (<literal>NIX-7</literal>).</para></listitem>
 | ||
| 
 | ||
|       <listitem><para>Removed misleading messages from
 | ||
|       <literal>nix-env -i</literal> (e.g., <literal>installing
 | ||
|       `foo'</literal> followed by <literal>uninstalling
 | ||
|       `foo'</literal>) (<literal>NIX-17</literal>).</para></listitem>
 | ||
| 
 | ||
|     </itemizedlist>
 | ||
| 
 | ||
|   </para></listitem>
 | ||
| 
 | ||
|   <listitem><para>Nix source distributions are a lot smaller now since
 | ||
|   we no longer include a full copy of the Berkeley DB source
 | ||
|   distribution (but only the bits we need).</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>Header files are now installed so that external
 | ||
|   programs can use the Nix libraries.</para></listitem>
 | ||
| 
 | ||
| </itemizedlist>
 | ||
| 
 | ||
| </section>
 | ||
| 
 | ||
| 
 | ||
| 
 | ||
| <!--==================================================================-->
 | ||
| 
 | ||
| <section><title>Release 0.9.2 (September 21, 2005)</title>
 | ||
| 
 | ||
| <para>This bug fix release fixes two problems on Mac OS X:
 | ||
| 
 | ||
| <itemizedlist>
 | ||
| 
 | ||
|   <listitem><para>If Nix was linked against statically linked versions
 | ||
|   of the ATerm or Berkeley DB library, there would be dynamic link
 | ||
|   errors at runtime.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para><command>nix-pull</command> and
 | ||
|   <command>nix-push</command> intermittently failed due to race
 | ||
|   conditions involving pipes and child processes with error messages
 | ||
|   such as <literal>open2: open(GLOB(0x180b2e4), >&=9) failed: Bad
 | ||
|   file descriptor at /nix/bin/nix-pull line 77</literal> (issue
 | ||
|   <literal>NIX-14</literal>).</para></listitem>
 | ||
| 
 | ||
| </itemizedlist>
 | ||
| 
 | ||
| </para>
 | ||
| 
 | ||
| </section>
 | ||
| 
 | ||
| 
 | ||
| 
 | ||
| <!--==================================================================-->
 | ||
| 
 | ||
| <section><title>Release 0.9.1 (September 20, 2005)</title>
 | ||
| 
 | ||
| <para>This bug fix release addresses a problem with the ATerm library
 | ||
| when the <option>--with-aterm</option> flag in
 | ||
| <command>configure</command> was <emphasis>not</emphasis> used.</para>
 | ||
| 
 | ||
| </section>
 | ||
| 
 | ||
| 
 | ||
| 
 | ||
| <!--==================================================================-->
 | ||
| 
 | ||
| <section><title>Release 0.9 (September 16, 2005)</title>
 | ||
| 
 | ||
| <para>NOTE: this version of Nix uses Berkeley DB 4.3 instead of 4.2.
 | ||
| The database is upgraded automatically, but you should be careful not
 | ||
| to use old versions of Nix that still use Berkeley DB 4.2.  In
 | ||
| particular, if you use a Nix installed through Nix, you should run
 | ||
| 
 | ||
| <screen>
 | ||
| $ nix-store --clear-substitutes</screen>
 | ||
| 
 | ||
| first.</para>
 | ||
| 
 | ||
| 
 | ||
| <itemizedlist>
 | ||
| 
 | ||
|   <listitem><para>Unpacking of patch sequences is much faster now
 | ||
|   since we no longer do redundant unpacking and repacking of
 | ||
|   intermediate paths.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>Nix now uses Berkeley DB 4.3.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>The <function>derivation</function> primitive is
 | ||
|   lazier.  Attributes of dependent derivations can mutually refer to
 | ||
|   each other (as long as there are no data dependencies on the
 | ||
|   <varname>outPath</varname> and <varname>drvPath</varname> attributes
 | ||
|   computed by <function>derivation</function>).</para>
 | ||
| 
 | ||
|   <para>For example, the expression <literal>derivation
 | ||
|   attrs</literal> now evaluates to (essentially)
 | ||
| 
 | ||
|   <programlisting>
 | ||
| attrs // {
 | ||
|   type = "derivation";
 | ||
|   outPath = derivation! attrs;
 | ||
|   drvPath = derivation! attrs;
 | ||
| }</programlisting>
 | ||
| 
 | ||
|   where <function>derivation!</function> is a primop that does the
 | ||
|   actual derivation instantiation (i.e., it does what
 | ||
|   <function>derivation</function> used to do).  The advantage is that
 | ||
|   it allows commands such as <command>nix-env -qa</command> and
 | ||
|   <command>nix-env -i</command> to be much faster since they no longer
 | ||
|   need to instantiate all derivations, just the
 | ||
|   <varname>name</varname> attribute.</para>
 | ||
| 
 | ||
|   <para>Also, it allows derivations to cyclically reference each
 | ||
|   other, for example,
 | ||
| 
 | ||
|   <programlisting>
 | ||
| webServer = derivation {
 | ||
|   ...
 | ||
|   hostName = "svn.cs.uu.nl";
 | ||
|   services = [svnService];
 | ||
| };
 | ||
|  
 | ||
| svnService = derivation {
 | ||
|   ...
 | ||
|   hostName = webServer.hostName;
 | ||
| };</programlisting>
 | ||
| 
 | ||
|   Previously, this would yield a black hole (infinite recursion).</para>
 | ||
|   
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem><para><command>nix-build</command> now defaults to using
 | ||
|   <filename>./default.nix</filename> if no Nix expression is
 | ||
|   specified.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para><command>nix-instantiate</command>, when applied to
 | ||
|   a Nix expression that evaluates to a function, will call the
 | ||
|   function automatically if all its arguments have
 | ||
|   defaults.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>Nix now uses libtool to build dynamic libraries.
 | ||
|   This reduces the size of executables.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>A new list concatenation operator
 | ||
|   <literal>++</literal>.  For example, <literal>[1 2 3] ++ [4 5
 | ||
|   6]</literal> evaluates to <literal>[1 2 3 4 5
 | ||
|   6]</literal>.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>Some currently undocumented primops to support
 | ||
|   low-level build management using Nix (i.e., using Nix as a Make
 | ||
|   replacement).  See the commit messages for <literal>r3578</literal>
 | ||
|   and <literal>r3580</literal>.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>Various bug fixes and performance
 | ||
|   improvements.</para></listitem>
 | ||
| 
 | ||
| </itemizedlist>
 | ||
| 
 | ||
| </section>
 | ||
| 
 | ||
| 
 | ||
| 
 | ||
| <!--==================================================================-->
 | ||
| 
 | ||
| <section><title>Release 0.8.1 (April 13, 2005)</title>
 | ||
| 
 | ||
| <para>This is a bug fix release.</para>
 | ||
| 
 | ||
| <itemizedlist>
 | ||
| 
 | ||
|   <listitem><para>Patch downloading was broken.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>The garbage collector would not delete paths that
 | ||
|   had references from invalid (but substitutable)
 | ||
|   paths.</para></listitem>
 | ||
| 
 | ||
| </itemizedlist>
 | ||
| 
 | ||
| </section>
 | ||
| 
 | ||
| 
 | ||
| 
 | ||
| <!--==================================================================-->
 | ||
| 
 | ||
| <section><title>Release 0.8 (April 11, 2005)</title>
 | ||
| 
 | ||
| <para>NOTE: the hashing scheme in Nix 0.8 changed (as detailed below).
 | ||
| As a result, <command>nix-pull</command> manifests and channels built
 | ||
| for Nix 0.7 and below will now work anymore.  However, the Nix
 | ||
| expression language has not changed, so you can still build from
 | ||
| source.  Also, existing user environments continue to work.  Nix 0.8
 | ||
| will automatically upgrade the database schema of previous
 | ||
| installations when it is first run.</para>
 | ||
| 
 | ||
| <para>If you get the error message
 | ||
| 
 | ||
| <screen>
 | ||
| you have an old-style manifest `/nix/var/nix/manifests/[...]'; please
 | ||
| delete it</screen>
 | ||
| 
 | ||
| you should delete previously downloaded manifests:
 | ||
| 
 | ||
| <screen>
 | ||
| $ rm /nix/var/nix/manifests/*</screen>
 | ||
| 
 | ||
| If <command>nix-channel</command> gives the error message
 | ||
| 
 | ||
| <screen>
 | ||
| manifest `http://catamaran.labs.cs.uu.nl/dist/nix/channels/[channel]/MANIFEST'
 | ||
| is too old (i.e., for Nix <= 0.7)</screen>
 | ||
| 
 | ||
| then you should unsubscribe from the offending channel
 | ||
| (<command>nix-channel --remove
 | ||
| <replaceable>URL</replaceable></command>; leave out
 | ||
| <literal>/MANIFEST</literal>), and subscribe to the same URL, with
 | ||
| <literal>channels</literal> replaced by <literal>channels-v3</literal>
 | ||
| (e.g., <link
 | ||
| xlink:href='http://catamaran.labs.cs.uu.nl/dist/nix/channels-v3/nixpkgs-unstable'
 | ||
| />).</para>
 | ||
| 
 | ||
| <para>Nix 0.8 has the following improvements:
 | ||
| 
 | ||
| <itemizedlist>
 | ||
| 
 | ||
|   <listitem><para>The cryptographic hashes used in store paths are now
 | ||
|   160 bits long, but encoded in base-32 so that they are still only 32
 | ||
|   characters long (e.g.,
 | ||
|   <filename>/nix/store/csw87wag8bqlqk7ipllbwypb14xainap-atk-1.9.0</filename>).
 | ||
|   (This is actually a 160 bit truncation of a SHA-256
 | ||
|   hash.)</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>Big cleanups and simplifications of the basic store
 | ||
|   semantics.  The notion of “closure store expressions” is gone (and
 | ||
|   so is the notion of “successors”); the file system references of a
 | ||
|   store path are now just stored in the database.</para>
 | ||
| 
 | ||
|   <para>For instance, given any store path, you can query its closure:
 | ||
| 
 | ||
|   <screen>
 | ||
| $ nix-store -qR $(which firefox)
 | ||
| ... lots of paths ...</screen>
 | ||
| 
 | ||
|   Also, Nix now remembers for each store path the derivation that
 | ||
|   built it (the “deriver”):
 | ||
| 
 | ||
|   <screen>
 | ||
| $ nix-store -qR $(which firefox)
 | ||
| /nix/store/4b0jx7vq80l9aqcnkszxhymsf1ffa5jd-firefox-1.0.1.drv</screen>
 | ||
| 
 | ||
|   So to see the build-time dependencies, you can do
 | ||
| 
 | ||
|   <screen>
 | ||
| $ nix-store -qR $(nix-store -qd $(which firefox))</screen>
 | ||
| 
 | ||
|   or, in a nicer format:
 | ||
| 
 | ||
|   <screen>
 | ||
| $ nix-store -q --tree $(nix-store -qd $(which firefox))</screen>
 | ||
| 
 | ||
|   </para>
 | ||
| 
 | ||
|   <para>File system references are also stored in reverse.  For
 | ||
|   instance, you can query all paths that directly or indirectly use a
 | ||
|   certain Glibc:
 | ||
| 
 | ||
|   <screen>
 | ||
| $ nix-store -q --referrers-closure \
 | ||
|     /nix/store/8lz9yc6zgmc0vlqmn2ipcpkjlmbi51vv-glibc-2.3.4</screen>
 | ||
| 
 | ||
|   </para>
 | ||
|   
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem><para>The concept of fixed-output derivations has been
 | ||
|   formalised.  Previously, functions such as
 | ||
|   <function>fetchurl</function> in Nixpkgs used a hack (namely,
 | ||
|   explicitly specifying a store path hash) to prevent changes to, say,
 | ||
|   the URL of the file from propagating upwards through the dependency
 | ||
|   graph, causing rebuilds of everything.  This can now be done cleanly
 | ||
|   by specifying the <varname>outputHash</varname> and
 | ||
|   <varname>outputHashAlgo</varname> attributes.  Nix itself checks
 | ||
|   that the content of the output has the specified hash.  (This is
 | ||
|   important for maintaining certain invariants necessary for future
 | ||
|   work on secure shared stores.)</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>One-click installation :-) It is now possible to
 | ||
|   install any top-level component in Nixpkgs directly, through the web
 | ||
|   — see, e.g., <link
 | ||
|   xlink:href='http://catamaran.labs.cs.uu.nl/dist/nixpkgs-0.8/' />.
 | ||
|   All you have to do is associate
 | ||
|   <filename>/nix/bin/nix-install-package</filename> with the MIME type
 | ||
|   <literal>application/nix-package</literal> (or the extension
 | ||
|   <filename>.nixpkg</filename>), and clicking on a package link will
 | ||
|   cause it to be installed, with all appropriate dependencies.  If you
 | ||
|   just want to install some specific application, this is easier than
 | ||
|   subscribing to a channel.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para><command>nix-store -r
 | ||
|   <replaceable>PATHS</replaceable></command> now builds all the
 | ||
|   derivations PATHS in parallel.  Previously it did them sequentially
 | ||
|   (though exploiting possible parallelism between subderivations).
 | ||
|   This is nice for build farms.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para><command>nix-channel</command> has new operations
 | ||
|   <option>--list</option> and
 | ||
|   <option>--remove</option>.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>New ways of installing components into user
 | ||
|   environments:
 | ||
| 
 | ||
|   <itemizedlist>
 | ||
| 
 | ||
|     <listitem><para>Copy from another user environment:
 | ||
| 
 | ||
|     <screen>
 | ||
| $ nix-env -i --from-profile .../other-profile firefox</screen>
 | ||
| 
 | ||
|     </para></listitem>
 | ||
| 
 | ||
|     <listitem><para>Install a store derivation directly (bypassing the
 | ||
|     Nix expression language entirely):
 | ||
| 
 | ||
|     <screen>
 | ||
| $ nix-env -i /nix/store/z58v41v21xd3...-aterm-2.3.1.drv</screen>
 | ||
| 
 | ||
|     (This is used to implement <command>nix-install-package</command>,
 | ||
|     which is therefore immune to evolution in the Nix expression
 | ||
|     language.)</para></listitem>
 | ||
| 
 | ||
|     <listitem><para>Install an already built store path directly:
 | ||
| 
 | ||
|     <screen>
 | ||
| $ nix-env -i /nix/store/hsyj5pbn0d9i...-aterm-2.3.1</screen>
 | ||
| 
 | ||
|     </para></listitem>
 | ||
| 
 | ||
|     <listitem><para>Install the result of a Nix expression specified
 | ||
|     as a command-line argument:
 | ||
| 
 | ||
|     <screen>
 | ||
| $ nix-env -f .../i686-linux.nix -i -E 'x: x.firefoxWrapper'</screen>
 | ||
| 
 | ||
|     The difference with the normal installation mode is that
 | ||
|     <option>-E</option> does not use the <varname>name</varname>
 | ||
|     attributes of derivations.  Therefore, this can be used to
 | ||
|     disambiguate multiple derivations with the same
 | ||
|     name.</para></listitem>
 | ||
| 
 | ||
|   </itemizedlist></para></listitem>
 | ||
| 
 | ||
|   <listitem><para>A hash of the contents of a store path is now stored
 | ||
|   in the database after a succesful build.  This allows you to check
 | ||
|   whether store paths have been tampered with: <command>nix-store
 | ||
|   --verify --check-contents</command>.</para></listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
| 
 | ||
|     <para>Implemented a concurrent garbage collector.  It is now
 | ||
|     always safe to run the garbage collector, even if other Nix
 | ||
|     operations are happening simultaneously.</para>
 | ||
| 
 | ||
|     <para>However, there can still be GC races if you use
 | ||
|     <command>nix-instantiate</command> and <command>nix-store
 | ||
|     --realise</command> directly to build things.  To prevent races,
 | ||
|     use the <option>--add-root</option> flag of those commands.</para>
 | ||
| 
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem><para>The garbage collector now finally deletes paths in
 | ||
|   the right order (i.e., topologically sorted under the “references”
 | ||
|   relation), thus making it safe to interrupt the collector without
 | ||
|   risking a store that violates the closure
 | ||
|   invariant.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>Likewise, the substitute mechanism now downloads
 | ||
|   files in the right order, thus preserving the closure invariant at
 | ||
|   all times.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>The result of <command>nix-build</command> is now
 | ||
|   registered as a root of the garbage collector.  If the
 | ||
|   <filename>./result</filename> link is deleted, the GC root
 | ||
|   disappears automatically.</para></listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
| 
 | ||
|     <para>The behaviour of the garbage collector can be changed
 | ||
|     globally by setting options in
 | ||
|     <filename>/nix/etc/nix/nix.conf</filename>.
 | ||
| 
 | ||
|     <itemizedlist>
 | ||
| 
 | ||
|       <listitem><para><literal>gc-keep-derivations</literal> specifies
 | ||
|       whether deriver links should be followed when searching for live
 | ||
|       paths.</para></listitem>
 | ||
| 
 | ||
|       <listitem><para><literal>gc-keep-outputs</literal> specifies
 | ||
|       whether outputs of derivations should be followed when searching
 | ||
|       for live paths.</para></listitem>
 | ||
| 
 | ||
|       <listitem><para><literal>env-keep-derivations</literal>
 | ||
|       specifies whether user environments should store the paths of
 | ||
|       derivations when they are added (thus keeping the derivations
 | ||
|       alive).</para></listitem>
 | ||
| 
 | ||
|     </itemizedlist>
 | ||
| 
 | ||
|   </para></listitem>
 | ||
| 
 | ||
|   <listitem><para>New <command>nix-env</command> query flags
 | ||
|   <option>--drv-path</option> and
 | ||
|   <option>--out-path</option>.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para><command>fetchurl</command> allows SHA-1 and SHA-256
 | ||
|   in addition to MD5.  Just specify the attribute
 | ||
|   <varname>sha1</varname> or <varname>sha256</varname> instead of
 | ||
|   <varname>md5</varname>.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>Manual updates.</para></listitem>
 | ||
| 
 | ||
| </itemizedlist>
 | ||
| 
 | ||
| </para>
 | ||
| 
 | ||
| </section>
 | ||
| 
 | ||
| 
 | ||
| 
 | ||
| <!--==================================================================-->
 | ||
| 
 | ||
| <section><title>Release 0.7 (January 12, 2005)</title>
 | ||
| 
 | ||
| <itemizedlist>
 | ||
| 
 | ||
|   <listitem><para>Binary patching.  When upgrading components using
 | ||
|   pre-built binaries (through nix-pull / nix-channel), Nix can
 | ||
|   automatically download and apply binary patches to already installed
 | ||
|   components instead of full downloads.  Patching is “smart”: if there
 | ||
|   is a <emphasis>sequence</emphasis> of patches to an installed
 | ||
|   component, Nix will use it.  Patches are currently generated
 | ||
|   automatically between Nixpkgs (pre-)releases.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>Simplifications to the substitute
 | ||
|   mechanism.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>Nix-pull now stores downloaded manifests in
 | ||
|   <filename>/nix/var/nix/manifests</filename>.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>Metadata on files in the Nix store is canonicalised
 | ||
|   after builds: the last-modified timestamp is set to 0 (00:00:00
 | ||
|   1/1/1970), the mode is set to 0444 or 0555 (readable and possibly
 | ||
|   executable by all; setuid/setgid bits are dropped), and the group is
 | ||
|   set to the default.  This ensures that the result of a build and an
 | ||
|   installation through a substitute is the same; and that timestamp
 | ||
|   dependencies are revealed.</para></listitem>
 | ||
| 
 | ||
| </itemizedlist>
 | ||
| 
 | ||
| </section>
 | ||
| 
 | ||
| 
 | ||
| 
 | ||
| <!--==================================================================-->
 | ||
| 
 | ||
| <section><title>Release 0.6 (November 14, 2004)</title>
 | ||
| 
 | ||
| <itemizedlist>
 | ||
| 
 | ||
|   <listitem>
 | ||
|     <para>Rewrite of the normalisation engine.
 | ||
| 
 | ||
|     <itemizedlist>
 | ||
| 
 | ||
|       <listitem><para>Multiple builds can now be performed in parallel
 | ||
|       (option <option>-j</option>).</para></listitem>
 | ||
| 
 | ||
|       <listitem><para>Distributed builds.  Nix can now call a shell
 | ||
|       script to forward builds to Nix installations on remote
 | ||
|       machines, which may or may not be of the same platform
 | ||
|       type.</para></listitem>
 | ||
| 
 | ||
|       <listitem><para>Option <option>--fallback</option> allows
 | ||
|       recovery from broken substitutes.</para></listitem>
 | ||
| 
 | ||
|       <listitem><para>Option <option>--keep-going</option> causes
 | ||
|       building of other (unaffected) derivations to continue if one
 | ||
|       failed.</para></listitem>
 | ||
| 
 | ||
|     </itemizedlist>
 | ||
| 
 | ||
|     </para>
 | ||
| 
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem><para>Improvements to the garbage collector (i.e., it
 | ||
|   should actually work now).</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>Setuid Nix installations allow a Nix store to be
 | ||
|   shared among multiple users.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>Substitute registration is much faster
 | ||
|   now.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>A utility <command>nix-build</command> to build a
 | ||
|   Nix expression and create a symlink to the result int the current
 | ||
|   directory; useful for testing Nix derivations.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>Manual updates.</para></listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
| 
 | ||
|     <para><command>nix-env</command> changes:
 | ||
| 
 | ||
|     <itemizedlist>
 | ||
| 
 | ||
|       <listitem><para>Derivations for other platforms are filtered out
 | ||
|       (which can be overriden using
 | ||
|       <option>--system-filter</option>).</para></listitem>
 | ||
| 
 | ||
|       <listitem><para><option>--install</option> by default now
 | ||
|       uninstall previous derivations with the same
 | ||
|       name.</para></listitem>
 | ||
| 
 | ||
|       <listitem><para><option>--upgrade</option> allows upgrading to a
 | ||
|       specific version.</para></listitem>
 | ||
| 
 | ||
|       <listitem><para>New operation
 | ||
|       <option>--delete-generations</option> to remove profile
 | ||
|       generations (necessary for effective garbage
 | ||
|       collection).</para></listitem>
 | ||
| 
 | ||
|       <listitem><para>Nicer output (sorted,
 | ||
|       columnised).</para></listitem>
 | ||
| 
 | ||
|     </itemizedlist>
 | ||
|     
 | ||
|     </para>
 | ||
| 
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem><para>More sensible verbosity levels all around (builder
 | ||
|   output is now shown always, unless <option>-Q</option> is
 | ||
|   given).</para></listitem>
 | ||
| 
 | ||
|   <listitem>
 | ||
| 
 | ||
|     <para>Nix expression language changes:
 | ||
| 
 | ||
|     <itemizedlist>
 | ||
|       
 | ||
|       <listitem><para>New language construct: <literal>with
 | ||
|       <replaceable>E1</replaceable>;
 | ||
|       <replaceable>E2</replaceable></literal> brings all attributes
 | ||
|       defined in the attribute set <replaceable>E1</replaceable> in
 | ||
|       scope in <replaceable>E2</replaceable>.</para></listitem>
 | ||
| 
 | ||
|       <listitem><para>Added a <function>map</function>
 | ||
|       function.</para></listitem>
 | ||
| 
 | ||
|       <listitem><para>Various new operators (e.g., string
 | ||
|       concatenation).</para></listitem>
 | ||
| 
 | ||
|     </itemizedlist>
 | ||
| 
 | ||
|     </para>
 | ||
| 
 | ||
|   </listitem>
 | ||
| 
 | ||
|   <listitem><para>Expression evaluation is much
 | ||
|   faster.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>An Emacs mode for editing Nix expressions (with
 | ||
|   syntax highlighting and indentation) has been
 | ||
|   added.</para></listitem>
 | ||
| 
 | ||
|   <listitem><para>Many bug fixes.</para></listitem>
 | ||
| 
 | ||
| </itemizedlist>
 | ||
| 
 | ||
| </section>
 | ||
| 
 | ||
| 
 | ||
| 
 | ||
| <!--==================================================================-->
 | ||
| 
 | ||
| <section><title>Release 0.5 and earlier</title>
 | ||
| 
 | ||
| <para>Please refer to the Subversion commit log messages.</para>
 | ||
| 
 | ||
| </section>
 | ||
| 
 | ||
| 
 | ||
| 
 | ||
| </article>
 |