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151e61fa5a
derivations with names matching the derivations being installed. The option `--preserve-installed / -P' overrides this behaviour.
860 lines
26 KiB
XML
860 lines
26 KiB
XML
<refentry>
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<refnamediv>
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<refname>nix-env</refname>
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<refpurpose>manipulate or query Nix user environments</refpurpose>
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</refnamediv>
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<refsynopsisdiv>
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<cmdsynopsis>
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<command>nix-env</command>
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&opt-common-syn;
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<arg>
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<group choice='req'>
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<arg choice='plain'><option>--file</option></arg>
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<arg choice='plain'><option>-f</option></arg>
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</group>
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<replaceable>path</replaceable>
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</arg>
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<arg>
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<group choice='req'>
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<arg choice='plain'><option>--profile</option></arg>
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<arg choice='plain'><option>-p</option></arg>
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</group>
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<replaceable>path</replaceable>
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</arg>
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<arg><option>--dry-run</option></arg>
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<arg choice='plain'><replaceable>operation</replaceable></arg>
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<arg rep='repeat'><replaceable>options</replaceable></arg>
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<arg rep='repeat'><replaceable>arguments</replaceable></arg>
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</cmdsynopsis>
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</refsynopsisdiv>
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<refsection>
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<title>Description</title>
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<para>
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The command <command>nix-env</command> is used to manipulate Nix
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user environments. User environments are sets of software
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components available to a user at some point in time. In other
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words, they are a synthesised view of the programs available in
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the Nix store. There may be many user environments: different
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users can have different environments, and individual users can
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switch between different environments.
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</para>
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<!-- <para>
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Environments are manipulated by operations such as the
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installation and removal of components (hereafter called
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<emphasis>derivations</emphasis>). These operations are not
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destructive: rather than overwrite the current environment, they
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create a new environment to which we can then atomically
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<emphasis>switch</emphasis> by flipping a symlink.
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</para> -->
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<para>
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<command>nix-env</command> takes exactly one
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<emphasis>operation</emphasis> flag which indicates the
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subcommand to be performed. These are documented below.
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</para>
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</refsection>
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<!--######################################################################-->
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<refsection>
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<title>Common options</title>
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<para>
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This section lists the options that are common to all
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operations. These options are allowed for every subcommand,
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though they may not always have an effect.
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</para>
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<variablelist>
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&opt-common;
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<varlistentry>
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<term><option>--file</option> / <option>-f</option></term>
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<listitem>
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<para>
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Specifies the Nix expression (designated below as the
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<emphasis>active Nix expression</emphasis>) used by the
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<option>--install</option>, <option>--upgrade</option>,
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and <option>--query --available</option> operations to
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obtain derivations. The default is
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<filename>~/.nix-defexpr</filename>.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><option>--profile</option> / <option>-p</option></term>
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<listitem>
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<para>
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Specifies the profile to be used by those operations that
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operate on a profile (designated below as the
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<emphasis>active profile</emphasis>). A profile is
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sequence of user environments called
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<emphasis>generations</emphasis>, one of which is the
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<emphasis>current generation</emphasis>. The default
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profile is the target of the symbolic link
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<filename>~/.nix-profile</filename> (see below).
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><option>--dry-run</option></term>
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<listitem>
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<para>
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For the <option>--install</option>,
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<option>--upgrade</option>, <option>--uninstall</option>,
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<option>--switch-generation</option> and
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<option>--rollback</option> operations, this flag will
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cause <command>nix-env</command> to print what
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<emphasis>would</emphasis> be done if this flag had not
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been specified, without actually doing it.
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</para>
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</listitem>
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</varlistentry>
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</variablelist>
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</refsection>
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<!--######################################################################-->
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<refsection>
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<title>Files</title>
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<variablelist>
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<varlistentry>
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<term><filename>~/.nix-defexpr</filename></term>
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<listitem>
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<para>
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The default Nix expression used by the
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<option>--install</option>, <option>--upgrade</option>,
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and <option>--query --available</option> operations to
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obtain derivations. It is generally a symbolic link to
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some other location set using the
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<option>--import</option> operation. The
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<option>--file</option> option may be used to override
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this default.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><filename>~/.nix-profile</filename></term>
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<listitem>
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<para>
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A symbolic link to the user's current profile. By
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default, this symlink points to
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<filename><replaceable>prefix</replaceable>/var/nix/profiles/default</filename>.
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The <envar>PATH</envar> environment variable should
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include <filename>~/.nix-profile/bin</filename> for the
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user environment to be visible to the user.
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</para>
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</listitem>
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</varlistentry>
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</variablelist>
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</refsection>
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<!--######################################################################-->
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<refsection>
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<title>Operation <option>--install</option></title>
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<refsection>
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<title>Synopsis</title>
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<cmdsynopsis>
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<command>nix-env</command>
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<group choice='req'>
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<arg choice='plain'><option>--install</option></arg>
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<arg choice='plain'><option>-i</option></arg>
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</group>
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<group choice='opt'>
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<arg choice='plain'><option>--preserve-installed</option></arg>
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<arg choice='plain'><option>-P</option></arg>
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</group>
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<arg choice='plain' rep='repeat'><replaceable>drvnames</replaceable></arg>
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</cmdsynopsis>
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</refsection>
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<refsection>
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<title>Description</title>
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<para>
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The install operation creates a new user environment, based on
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the current generation of the active profile, to which the
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derivations designated by <replaceable>drvnames</replaceable>
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in the active Nix expression are added.
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</para>
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<para>
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Currently installed derivations with a name equal to the name
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of a derivation being added are removed unless the option
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<option>--preserve-installed</option> is specified.
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</para>
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</refsection>
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<refsection>
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<title>Flags</title>
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<variablelist>
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<varlistentry>
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<term><option>--preserve-installed</option> / <option>-P</option></term>
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<listitem>
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<para>
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Do not remove derivations with a name matching one of
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the derivations being installed. Usually, trying to
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have two versions of the same package installed in the
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same generation of a profile will lead to an error in
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building the generation, due to file name clashes
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between the two versions. However, this is not the case
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for all packages.
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</para>
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</listitem>
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</varlistentry>
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</variablelist>
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</refsection>
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<refsection>
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<title>Examples</title>
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<screen>
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$ nix-env --install gcc-3.3.2 <lineannotation>(install specific version)</lineannotation>
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installing `gcc-3.3.2'
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uninstalling `gcc-3.1' <lineannotation>(previously installed version is removed)</lineannotation>
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$ nix-env --install gcc <lineannotation>(just pick any version)</lineannotation>
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$ nix-env -f ~/foo.nix -i '*' <lineannotation>(install everything in <filename>foo.nix</filename>)</lineannotation></screen>
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</refsection>
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</refsection>
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<!--######################################################################-->
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<refsection>
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<title>Operation <option>--upgrade</option></title>
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<refsection>
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<title>Synopsis</title>
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<cmdsynopsis>
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<command>nix-env</command>
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<group choice='req'>
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<arg choice='plain'><option>--upgrade</option></arg>
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<arg choice='plain'><option>-u</option></arg>
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</group>
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<group choice='opt'>
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<arg choice='plain'><option>--lt</option></arg>
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<arg choice='plain'><option>--leq</option></arg>
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<arg choice='plain'><option>--always</option></arg>
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</group>
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<arg choice='plain' rep='repeat'><replaceable>drvnames</replaceable></arg>
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</cmdsynopsis>
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</refsection>
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<refsection>
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<title>Description</title>
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<para>
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The upgrade operation creates a new user environment, based on
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the current generation of the active profile, in which all
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derivations designated by <replaceable>drvnames</replaceable>
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for which there are newer versions in the active Nix
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expression are replaced by those newer versions. Matching
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derivations for which there are no newer versions are left
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untouched; this is not an error. It is also not an error if
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an element of <replaceable>drvnames</replaceable> matches no
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installed derivations.
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</para>
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<para>
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If multiple derivations in the active Nix expression match an
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installed derivation, the one with the highest version is
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selected.
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</para>
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</refsection>
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<refsection>
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<title>Flags</title>
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<variablelist>
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<varlistentry>
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<term><option>--lt</option></term>
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<listitem>
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<para>
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Only upgrade a derivation to newer versions. This is
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the default.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><option>--leq</option></term>
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<listitem>
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<para>
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In addition to upgrading to newer versions, also
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<quote>upgrade</quote> to derivations that have the same
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version. Version are not a unique identification of a
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derivation, so there may be many derivations that have
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the same version. This flag may be useful to force
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<quote>synchronisation</quote> between the installed and
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available derivations.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><option>--always</option></term>
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<listitem>
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<para>
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In addition to upgrading to newer versions, also
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<quote>upgrade</quote> to derivations that have the same
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or a lower version. I.e., derivations may actually be
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downgraded depending on what is available in the active
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Nix expression.
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</para>
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</listitem>
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</varlistentry>
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</variablelist>
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</refsection>
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<refsection>
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<title>Examples</title>
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<screen>
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$ nix-env --upgrade gcc
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upgrading `gcc-3.3.1' to `gcc-3.4'
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$ nix-env -u gcc-3.3.2 --always <lineannotation>(switch to a specific version)</lineannotation>
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upgrading `gcc-3.4' to `gcc-3.3.2'
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$ nix-env --upgrade pan
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<lineannotation>(no upgrades available, so nothing happens)</lineannotation>
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$ nix-env -u '*' <lineannotation>(try to upgrade everything)</lineannotation>
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upgrading `hello-2.1.2' to `hello-2.1.3'
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upgrading `mozilla-1.2' to `mozilla-1.4'</screen>
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</refsection>
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<refsection>
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<title>Versions</title>
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<para>
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The upgrade operation determines whether a derivation
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<varname>y</varname> is an upgrade of a derivation
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<varname>x</varname> by looking at their respective
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<literal>name</literal> attributes. The names (e.g.,
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<literal>gcc-3.3.1</literal> are split into two parts: the
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package name (<literal>gcc</literal>), and the version
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(<literal>3.3.1</literal>). The version part starts after the
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first dash not following by a letter. <varname>x</varname> is
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considered an upgrade of <varname>y</varname> if their package
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names match, and the version of <varname>y</varname> is higher
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that that of <varname>x</varname>.
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</para>
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<para>
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The versions are compared by splitting them into contiguous
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components of numbers and letters. E.g.,
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<literal>3.3.1pre5</literal> is split into <literal>[3, 3, 1,
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"pre", 5]</literal>. These lists are then compared
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lexicographically (from left to right). Corresponding
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components <varname>a</varname> and <varname>b</varname> are
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compared as follows. If they are both numbers, integer
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comparison is used. If <varname>a</varname> is an empty
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string and <varname>b</varname> is a number,
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<varname>a</varname> is considered less than
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<varname>b</varname>. The special string component
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<literal>pre</literal> (for <emphasis>pre-release</emphasis>)
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is considered to be less than other components. String
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components are considered less than number components.
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Otherwise, they are compared lexicographically (i.e., using
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case-sensitive string comparison).
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</para>
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<para>
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This is illustrated by the following examples:
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<screen>
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1.0 < 2.3
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2.1 < 2.3
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2.3 = 2.3
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2.5 > 2.3
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3.1 > 2.3
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2.3.1 > 2.3
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2.3.1 > 2.3a
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2.3pre1 < 2.3
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2.3pre3 < 2.3pre12
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2.3a < 2.3c
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2.3pre1 < 2.3c
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2.3pre1 < 2.3q</screen>
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</para>
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</refsection>
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</refsection>
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<!--######################################################################-->
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<refsection>
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<title>Operation <option>--uninstall</option></title>
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<refsection>
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<title>Synopsis</title>
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<cmdsynopsis>
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<command>nix-env</command>
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<group choice='req'>
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<arg choice='plain'><option>--uninstall</option></arg>
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<arg choice='plain'><option>-e</option></arg>
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</group>
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<arg choice='plain' rep='repeat'><replaceable>drvnames</replaceable></arg>
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</cmdsynopsis>
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</refsection>
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<refsection>
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<title>Description</title>
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<para>
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The uninstall operation creates a new user environment, based
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on the current generation of the active profile, from which the
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derivations designated by <replaceable>drvnames</replaceable>
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are removed.
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</para>
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</refsection>
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<refsection>
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<title>Examples</title>
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<screen>
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$ nix-env --uninstall gcc
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$ nix-env -e '*' <lineannotation>(remove everything)</lineannotation></screen>
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</refsection>
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</refsection>
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<!--######################################################################-->
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<refsection>
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<title>Operation <option>--query</option></title>
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<refsection>
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<title>Synopsis</title>
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<cmdsynopsis>
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<command>nix-env</command>
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<group choice='req'>
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<arg choice='plain'><option>--query</option></arg>
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<arg choice='plain'><option>-q</option></arg>
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</group>
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<group choice='opt'>
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<arg choice='plain'><option>--installed</option></arg>
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<arg choice='plain'><option>--available</option></arg>
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<arg choice='plain'><option>-a</option></arg>
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</group>
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<group choice='req'>
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<arg choice='plain'><option>--name</option></arg>
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<arg choice='plain'><option>--expr</option></arg>
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<arg choice='plain'><option>--status</option></arg>
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<arg choice='plain'><option>-s</option></arg>
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</group>
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</cmdsynopsis>
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</refsection>
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<refsection>
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<title>Description</title>
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<para>
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The query operation displays information about either the
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derivations that are installed in the current generation of
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the active profile (<option>--installed</option>), or the
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derivations that are available for installation in the active
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Nix expression (<option>--available</option>).
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</para>
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<para>
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The derivations are sorted by their <literal>name</literal>
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attributes.
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</para>
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</refsection>
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<refsection>
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<title>Source selection</title>
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<para>
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The following flags specify the set of derivations on which
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the query operates.
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</para>
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<variablelist>
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<varlistentry>
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<term><option>--installed</option></term>
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<listitem>
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<para>
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The query operates on the derivations that are installed
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in the current generation of the active profile. This
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is the default
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><option>--available</option> / <option>-a</option></term>
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<listitem>
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<para>
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The query operates on the derivations that are available
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in the active Nix expression.
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</para>
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</listitem>
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</varlistentry>
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</variablelist>
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</refsection>
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<refsection>
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<title>Queries</title>
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<para>
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The following flags specify what information to display about
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the selected derivations. Only one type of query may be
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specified.
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</para>
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|
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<variablelist>
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<varlistentry>
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|
<term><option>--name</option></term>
|
|
<listitem>
|
|
<para>
|
|
Prints the <literal>name</literal> attribute of each
|
|
derivation. This is the default.
|
|
</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><option>--expr</option></term>
|
|
<listitem>
|
|
<para>
|
|
Prints the store expression in the Nix store that
|
|
described the derivation.
|
|
</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><option>--status</option> / <option>-s</option></term>
|
|
<listitem>
|
|
<para>
|
|
Prints the <emphasis>status</emphasis> of each
|
|
derivation, followed by its <literal>name</literal>
|
|
attribute. The status consists of three characters.
|
|
The first is <literal>I</literal> or
|
|
<literal>-</literal>, indicating whether the derivation
|
|
is currently installed in the current generation of the
|
|
active profile. This is by definition the case for
|
|
<option>--installed</option>, but not for
|
|
<option>--available</option>. The second is
|
|
<literal>P</literal> or <literal>-</literal>, indicating
|
|
whether the derivation is present on the system. This
|
|
indicates whether installation of an available
|
|
derivation will require the derivation to be built. The
|
|
third is <literal>S</literal> or <literal>-</literal>,
|
|
indicating whether a substitute is available for the
|
|
derivation.
|
|
</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
|
|
</variablelist>
|
|
|
|
</refsection>
|
|
|
|
<refsection>
|
|
<title>Examples</title>
|
|
|
|
<screen>
|
|
$ nix-env -q <lineannotation>(show installed derivations)</lineannotation>
|
|
MozillaFirebird-0.7
|
|
bison-1.875c
|
|
docbook-xml-4.2
|
|
...
|
|
|
|
$ nix-env -qa <lineannotation>(show available derivations)</lineannotation>
|
|
GConf-2.4.0.1
|
|
MPlayer-1.0pre3
|
|
MozillaFirebird-0.7
|
|
ORBit2-2.8.3
|
|
...
|
|
|
|
$ nix-env -qas <lineannotation>(show status of available derivations)</lineannotation>
|
|
-P- GConf-2.4.0.1 <lineannotation>(not installed but present)</lineannotation>
|
|
--S MPlayer-1.0pre3 <lineannotation>(not present, but there is a substitute for fast installation)</lineannotation>
|
|
--S MozillaFirebird-0.7 <lineannotation>(i.e., this is not the installed Firebird, even though the version is the same!)</lineannotation>
|
|
IP- bison-1.875c <lineannotation>(installed and by definition present)</lineannotation>
|
|
...
|
|
|
|
$ nix-env -f ./foo.nix -qa <lineannotation>(show available derivations in the Nix expression <filename>foo.nix</filename>)</lineannotation>
|
|
foo-1.2.3</screen>
|
|
|
|
</refsection>
|
|
|
|
</refsection>
|
|
|
|
|
|
|
|
<!--######################################################################-->
|
|
|
|
<refsection>
|
|
<title>Operation <option>--switch-profile</option></title>
|
|
|
|
<refsection>
|
|
<title>Synopsis</title>
|
|
<cmdsynopsis>
|
|
<command>nix-env</command>
|
|
<group choice='req'>
|
|
<arg choice='plain'><option>--switch-profile</option></arg>
|
|
<arg choice='plain'><option>-S</option></arg>
|
|
</group>
|
|
<arg choice='req'><replaceable>path</replaceable></arg>
|
|
</cmdsynopsis>
|
|
</refsection>
|
|
|
|
<refsection>
|
|
<title>Description</title>
|
|
|
|
<para>
|
|
This operation makes <replaceable>path</replaceable> the
|
|
current profile for the user. That is, the symlink
|
|
<filename>~/.nix-profile</filename> is made to point to
|
|
<replaceable>path</replaceable>.
|
|
</para>
|
|
|
|
</refsection>
|
|
|
|
<refsection>
|
|
<title>Examples</title>
|
|
|
|
<screen>
|
|
$ nix-env -S ~/my-profile</screen>
|
|
|
|
</refsection>
|
|
|
|
</refsection>
|
|
|
|
|
|
|
|
<!--######################################################################-->
|
|
|
|
<refsection>
|
|
<title>Operation <option>--list-generations</option></title>
|
|
|
|
<refsection>
|
|
<title>Synopsis</title>
|
|
<cmdsynopsis>
|
|
<command>nix-env</command>
|
|
<arg choice='req'><option>--list-generations</option></arg>
|
|
</cmdsynopsis>
|
|
</refsection>
|
|
|
|
<refsection>
|
|
<title>Description</title>
|
|
|
|
<para>
|
|
This operation print a list of all the currently existing
|
|
generations for the active profile. These may be switched to
|
|
using the <option>--switch-generation</option> operation. It
|
|
also prints the creation date of the generation, and indicates
|
|
the current generation.
|
|
</para>
|
|
|
|
</refsection>
|
|
|
|
<refsection>
|
|
<title>Examples</title>
|
|
|
|
<screen>
|
|
$ nix-env --list-generations
|
|
95 2004-02-06 11:48:24
|
|
96 2004-02-06 11:49:01
|
|
97 2004-02-06 16:22:45
|
|
98 2004-02-06 16:24:33 (current)</screen>
|
|
|
|
</refsection>
|
|
|
|
</refsection>
|
|
|
|
|
|
|
|
<!--######################################################################-->
|
|
|
|
<refsection>
|
|
<title>Operation <option>--switch-generation</option></title>
|
|
|
|
<refsection>
|
|
<title>Synopsis</title>
|
|
<cmdsynopsis>
|
|
<command>nix-env</command>
|
|
<group choice='req'>
|
|
<arg choice='plain'><option>--switch-generation</option></arg>
|
|
<arg choice='plain'><option>-G</option></arg>
|
|
</group>
|
|
<arg choice='req'><replaceable>generation</replaceable></arg>
|
|
</cmdsynopsis>
|
|
</refsection>
|
|
|
|
<refsection>
|
|
<title>Description</title>
|
|
|
|
<para>
|
|
This operation makes generation number
|
|
<replaceable>generation</replaceable> the current generation
|
|
of the active profile. That is, if the
|
|
<filename><replaceable>profile</replaceable></filename> is the
|
|
path to the active profile, then the symlink
|
|
<filename><replaceable>profile</replaceable></filename> is
|
|
made to point to
|
|
<filename><replaceable>profile</replaceable>-<replaceable>generation</replaceable>-link</filename>,
|
|
which is in turn a symlink to the actual user environment in
|
|
the Nix store.
|
|
</para>
|
|
|
|
<para>
|
|
Switching will fail if the specified generation does not
|
|
exist.
|
|
</para>
|
|
|
|
</refsection>
|
|
|
|
<refsection>
|
|
<title>Examples</title>
|
|
|
|
<screen>
|
|
$ nix-env -G 42
|
|
switching from generation 50 to 42</screen>
|
|
|
|
</refsection>
|
|
|
|
</refsection>
|
|
|
|
|
|
|
|
<!--######################################################################-->
|
|
|
|
<refsection>
|
|
<title>Operation <option>--rollback</option></title>
|
|
|
|
<refsection>
|
|
<title>Synopsis</title>
|
|
<cmdsynopsis>
|
|
<command>nix-env</command>
|
|
<arg choice='req'><option>--rollback</option></arg>
|
|
</cmdsynopsis>
|
|
</refsection>
|
|
|
|
<refsection>
|
|
<title>Description</title>
|
|
|
|
<para>
|
|
This operation switches to the <quote>previous</quote>
|
|
generation of the active profile, that is, the highest
|
|
numbered generation lower than the current generation, if it
|
|
exists. It is just a convenience wrapper around
|
|
<option>--list-generations</option> and
|
|
<option>--switch-generation</option>.
|
|
</para>
|
|
|
|
</refsection>
|
|
|
|
<refsection>
|
|
<title>Examples</title>
|
|
|
|
<screen>
|
|
$ nix-env --rollback
|
|
switching from generation 92 to 91
|
|
|
|
$ nix-env --rolback
|
|
error: no generation older than the current (91) exists</screen>
|
|
|
|
</refsection>
|
|
|
|
</refsection>
|
|
|
|
|
|
|
|
<!--######################################################################-->
|
|
|
|
<refsection>
|
|
<title>Operation <option>--import</option></title>
|
|
|
|
<refsection>
|
|
<title>Synopsis</title>
|
|
<cmdsynopsis>
|
|
<command>nix-env</command>
|
|
<group choice='req'>
|
|
<arg choice='plain'><option>--import</option></arg>
|
|
<arg choice='plain'><option>-I</option></arg>
|
|
</group>
|
|
<arg choice='req'><replaceable>path</replaceable></arg>
|
|
</cmdsynopsis>
|
|
</refsection>
|
|
|
|
<refsection>
|
|
<title>Description</title>
|
|
|
|
<para>
|
|
This operation makes <replaceable>path</replaceable> the
|
|
default active Nix expression for the user. That is, the
|
|
symlink <filename>~/.nix-userenv</filename> is made to point
|
|
to <replaceable>path</replaceable>.
|
|
</para>
|
|
|
|
</refsection>
|
|
|
|
<refsection>
|
|
<title>Examples</title>
|
|
|
|
<screen>
|
|
$ nix-env -I ~/nixpkgs-0.5/</screen>
|
|
|
|
</refsection>
|
|
|
|
</refsection>
|
|
|
|
|
|
|
|
</refentry>
|