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* Manual fixes.

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Eelco Dolstra 2004-11-14 00:24:57 +00:00
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40
doc/manual/introduction.xml
View file

@ -12,11 +12,11 @@ features are:
<itemizedlist>
<listitem><para>It makes sure that dependency specifications are
complete. In general in a deployment system you have to specify for
each component what its dependencies are, but there are no guarantees
that this specification is complete. If you forget a dependency, then
the component will build and work correctly on
<listitem><para>It helps you make sure that dependency specifications
are complete. In general in a deployment system you have to specify
for each component what its dependencies are, but there are no
guarantees that this specification is complete. If you forget a
dependency, then the component will build and work correctly on
<emphasis>your</emphasis> machine if you have the dependency
installed, but not on the end user's machine if it's not
there.</para></listitem>
@ -25,8 +25,8 @@ there.</para></listitem>
variants</emphasis> of a component installed at the same time. In
contrast, in systems such as RPM different versions of the same
package tend to install to the same location in the file system, so
you installing one version will remove the other. This is especially
important if you want to have use applications that have conflicting
installing one version will remove the other. This is especially
important if you want to use applications that have conflicting
requirements on different versions of a component (e.g., application A
requires version 1.0 of library X, while application B requires a
non-backwards compatible version 1.1).</para></listitem>
@ -45,24 +45,23 @@ component to fail).</para></listitem>
<listitem><para>Likewise, it is possible to atomically roll back after
an install, upgrade, or uninstall action. That is, in a fast (O(1))
operation the previous configuration of the system will be restored.
This is because upgrade or uninstall actions doesn't actually remove
operation the previous configuration of the system can be restored.
This is because upgrade or uninstall actions don't actually remove
components from the system.</para></listitem>
<listitem><para>Unused components can be
<emphasis>garbage-collected</emphasis> automatically and safely.
I.e., when you remove an application from a profile, its dependencies
will be deleted by the garbage collector if there are no other active
applications that are using it.</para></listitem>
<emphasis>garbage-collected</emphasis> automatically and safely: when
you remove an application from a profile, its dependencies will be
deleted by the garbage collector only if there are no other active
applications using them.</para></listitem>
<listitem><para>Nix supports both source-based deployment models
(where you distribute <emphasis>Nix expressions</emphasis> that tell
Nix how to build software from source) and binary-based deployment
models. The latter is more-or-less transparent: installation of
components is always based on Nix expressions, but if those
expressions have been built before and Nix knows that the resulting
binaries are available somewhere, it will use those
instead.</para></listitem>
components is always based on Nix expressions, but if the expressions
have been built before and Nix knows that the resulting binaries are
available somewhere, it will use those instead.</para></listitem>
<listitem><para>Nix is flexible in the deployment policies that it
supports. There is a clear separation between the tools that
@ -80,13 +79,12 @@ This means that if a component was built succesfully once, it can be
rebuilt again on another machine and the result will be the same. We
cannot <emphasis>guarantee</emphasis> this (e.g., if the build depends
on the time-of-day), but Nix (and the tools in the Nix Packages
collection) takes special measures to help achieve
this.</para></listitem>
collection) takes special care to help achieve this.</para></listitem>
<listitem><para>Nix expressions (the things that tell Nix how to build
components) are self-contained: they describe not just components but
complete compositions. In other words, Nix expressions also describe
how to build all the dependencies. This is contrast to component
how to build all the dependencies. This is in contrast to component
specification languages like RPM spec files, which might say that a
component X depends on some other component Y, but since it does not
describe <emphasis>exactly</emphasis> what Y is, the result of
@ -111,7 +109,7 @@ platforms.</para></listitem>
also for <emphasis>service deployment</emphasis>, such as the
deployment of a complete web server with all its configuration files,
static pages, software dependencies, and so on. Nix's advantages for
software deployment also apply here, for instance, the ability
software deployment also apply here: for instance, the ability
trivially to have multiple configurations at the same time, or the
ability to do rollbacks.</para></listitem>

57
doc/manual/package-management.xml
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@ -31,7 +31,7 @@ Nix expressions called the Nix Package collection that contains
components ranging from basic development stuff such as GCC and Glibc,
to end-user applications like Mozilla Firefox. (Nix is however not
tied to the Nix Package collection; you could write your own Nix
expression based on that, or completely new.) You can download the
expression based on it, or completely new ones.) You can download the
latest version from <ulink
url='http://catamaran.labs.cs.uu.nl/dist/nix' />. You probably want
the latest unstable release; currently the stable releases tend to lag
@ -55,7 +55,7 @@ where <literal>nixpkgs-<replaceable>version</replaceable></literal> is
where you've unpacked the release.</para>
<para>It is also possible to see the <emphasis>status</emphasis> of
available component, i.e., whether they are installed into the user
available components, i.e., whether they are installed into the user
environment and/or present in the system:
<screen>
@ -69,12 +69,13 @@ IPS bison-1.875d
The first character (<literal>I</literal>) indicates whether the
component is installed in your current user environment. The second
(<literal>P</literal>) indicates whether it is present on your system
(in which case installing it into your user environment would be very
quick). The last one (<literal>S</literal>) indicates whether there
is a so-called <emphasis>substitute</emphasis> for the component,
which is Nix's mechanism for doing binary deployment. It just means
that Nix know that it can fetch a pre-built component from somewhere
(typically a network server) instead of building it locally.</para>
(in which case installing it into your user environment would be a
very quick operation). The last one (<literal>S</literal>) indicates
whether there is a so-called <emphasis>substitute</emphasis> for the
component, which is Nix's mechanism for doing binary deployment. It
just means that Nix know that it can fetch a pre-built component from
somewhere (typically a network server) instead of building it
locally.</para>
<para>So now that we have a set of Nix expressions we can build the
components contained in them. This is done using <literal>nix-env
@ -91,8 +92,8 @@ system</ulink>).</para>
<para>When you do this for the first time, Nix will start building
Subversion and all its dependencies. This will take quite a while —
typically an hour or two on modern machines. Fortunately, there is a
faster way (so just do a Ctrl-C on that install operation!): you just
need to tell Nix that pre-built binaries of all those components are
faster way (so do a Ctrl-C on that install operation!): you just need
to tell Nix that pre-built binaries of all those components are
available somewhere. This is done using the
<command>nix-pull</command> command, which must be supplied with a URL
containing a <emphasis>manifest</emphasis> describing what binaries
@ -110,7 +111,7 @@ downloading binaries from <systemitem
class='fqdomainname'>catamaran.labs.cs.uu.nl</systemitem>, instead of
building them from source. This might still take a while since all
dependencies must be downloaded, but on a reasonably fast connection
such as an ADSL line it's on the order of a few minutes.</para>
such as an DSL line it's on the order of a few minutes.</para>
<para>Naturally, packages can also be uninstalled:
@ -127,10 +128,10 @@ $ nix-env -f nixpkgs-<replaceable>version</replaceable> -u subversion</screen>
This will <emphasis>only</emphasis> upgrade Subversion if there is a
<quote>newer</quote> version in the new set of Nix expressions, as
defined by some pretty much arbitrary rules regarding ordering of
version numbers (which generally do what you'd expect of them). To
just unconditionally replace Subversion with whatever version is in
the Nix expressions, use <parameter>-i</parameter> instead of
defined by some pretty arbitrary rules regarding ordering of version
numbers (which generally do what you'd expect of them). To just
unconditionally replace Subversion with whatever version is in the Nix
expressions, use <parameter>-i</parameter> instead of
<parameter>-u</parameter>; <parameter>-i</parameter> will remove
whatever version is already installed.</para>
@ -261,7 +262,7 @@ lrwxrwxrwx 1 eelco ... default-43-link -> /nix/store/84c85f89ddbf...-user-env
lrwxrwxrwx 1 eelco ... default -> default-43-link</screen>
This shows a profile called <filename>default</filename>. The file
<filename>default</filename> itself is actually a symlink that point
<filename>default</filename> itself is actually a symlink that points
to the current generation. When we do a <command>nix-env</command>
operation, a new user environment and generation link are created
based on the current one, and finally the <filename>default</filename>
@ -295,13 +296,13 @@ $ nix-env --list-generations</screen></para>
figure above. You generally wouldn't have
<filename>/nix/var/nix/profiles/<replaceable>some-profile</replaceable>/bin</filename>
in your <envar>PATH</envar>. Rather, there is a symlink
<filename>~/.nix-profile</filename> that point to your current
<filename>~/.nix-profile</filename> that points to your current
profile. This means that you should put
<filename>~/.nix-profile/bin</filename> in your <envar>PATH</envar>
(and indeed, that's what the initialisation script
<filename>/nix/etc/profile.d/nix.sh</filename> does). This makes it
easier to switch to a different profile, which is exactly what the
command <command>nix-env --switch-profile</command> does:
easier to switch to a different profile. You can do that using the
command <command>nix-env --switch-profile</command>:
<screen>
$ nix-env --switch-profile /nix/var/nix/profiles/my-profile
@ -311,14 +312,14 @@ $ nix-env --switch-profile /nix/var/nix/profiles/default</screen>
These commands switch to the <filename>my-profile</filename> and
default profile, respectively. If the profile doesn't exist, it will
be created automatically. You should be careful about storing a
profile in another location that the <filename>profiles</filename>
directory, since otherwise it might not be used as a root to the
garbage collection (see section <xref linkend='sec-garbage-collection'
profile in another location than the <filename>profiles</filename>
directory, since otherwise it might not be used as a root of the
garbage collector (see section <xref linkend='sec-garbage-collection'
/>).</para>
<para>All <command>nix-env</command> operations work on the profile
pointed to by <command>~/.nix-profile</command>, but you can override
this on using the <option>--profile</option> option (abbreviation
this using the <option>--profile</option> option (abbreviation
<option>-p</option>):
<screen>
@ -335,7 +336,7 @@ This will <emphasis>not</emphasis> change the
<para><command>nix-env</command> operations such as upgrades
(<option>-u</option>) and uninstall (<option>-e</option>) never
actually delete components from the system. All they do (as shown
above) is to make a new user environment that no longer contains
above) is to create a new user environment that no longer contains
symlinks to the <quote>deleted</quote> components.</para>
<para>Of course, since disk space is not infinite, unused components
@ -414,10 +415,10 @@ a set of Nix expressions and a manifest. Using the command
with whatever is available at that URL.</para>
<para>You can <quote>subscribe</quote> to a channel using
<command>nix-channel --subscribe</command>, e.g.,
<command>nix-channel --add</command>, e.g.,
<screen>
$ nix-channel --subscribe http://catamaran.labs.cs.uu.nl/dist/nix/channels/nixpkgs-unstable</screen>
$ nix-channel --add http://catamaran.labs.cs.uu.nl/dist/nix/channels/nixpkgs-unstable</screen>
subscribes you to a channel that always contains that latest version
of the Nix Packages collection. (Instead of
@ -446,9 +447,9 @@ makes the union of each channel's Nix expressions the default for
$ nix-env -u '*'</screen>
to upgrade all components in your profile to the latest versions
available in the channels.</para>
available in the subscribed channels.</para>
</sect1>
</chapter>
</chapter>

4
doc/manual/quick-start.xml
View file

@ -102,7 +102,7 @@ $ nix-env --rollback</screen>
<listitem><para>You should periodically run the Nix garbage collector
to get rid of unused packages, since uninstalls or upgrades don't
actual delete them:
actually delete them:
<screen>
$ nix-env --delete-generations old
@ -115,4 +115,4 @@ second command actually deletes them.</para></listitem>
</orderedlist>
</chapter>
</chapter>