247 lines
8.6 KiB
XML
247 lines
8.6 KiB
XML
<section xmlns="http://docbook.org/ns/docbook"
|
|
xmlns:xlink="http://www.w3.org/1999/xlink"
|
|
xmlns:xi="http://www.w3.org/2001/XInclude"
|
|
version="5.0"
|
|
xml:id="ch-relnotes-0.8">
|
|
|
|
<title>Release 0.8 (2005-04-11)</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 not 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
|
|
<emphasis>URL</emphasis></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
|
|
<emphasis>PATHS</emphasis></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 successful 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>
|