Update .nixpkg description

doc/manual/command-ref/nix-install-package.xml

@@ -3,7 +3,7 @@
       xmlns:xi="http://www.w3.org/2001/XInclude"
       version="5.0"
       xml:id="sec-nix-install-package">
-  
+
 <refmeta>
   <refentrytitle>nix-install-package</refentrytitle>
   <manvolnum>1</manvolnum>
@@ -47,8 +47,7 @@
 <para>The command <command>nix-install-package</command> interactively
 installs a Nix Package file (<filename>*.nixpkg</filename>), which is
 a small file that contains a store path to be installed along with the
-URL of a <link linkend="sec-nix-push"><command>nix-push</command>
-manifest</link>.  The Nix Package file is either
+URL of a binary cache.  The Nix Package file is either
 <replaceable>file</replaceable>, or automatically downloaded from
 <replaceable>url</replaceable> if the <option>--url</option> switch is
 used.</para>
@@ -76,7 +75,7 @@ to restart itself with <command>xterm</command>,
 <refsection><title>Options</title>
 
 <variablelist>
-  
+
   <varlistentry><term><option>--non-interactive</option></term>
 
     <listitem><para>Do not open a new terminal window and do not ask
@@ -139,14 +138,14 @@ The elements are as follows:
 <variablelist>
 
   <varlistentry><term><literal>NIXPKG1</literal></term>
-  
+
     <listitem><para>The version of the Nix Package
     file.</para></listitem>
 
   </varlistentry>
 
   <varlistentry><term><replaceable>manifestURL</replaceable></term>
-  
+
     <listitem><para>The manifest to be pulled by
     <command>nix-pull</command>.  The manifest must contain
     <replaceable>outPath</replaceable>.</para></listitem>
@@ -154,21 +153,21 @@ The elements are as follows:
   </varlistentry>
 
   <varlistentry><term><replaceable>name</replaceable></term>
-  
+
     <listitem><para>The symbolic name and version of the
     package.</para></listitem>
 
   </varlistentry>
 
   <varlistentry><term><replaceable>system</replaceable></term>
-  
+
     <listitem><para>The platform identifier of the platform for which
     this binary package is intended.</para></listitem>
 
   </varlistentry>
 
   <varlistentry><term><replaceable>drvPath</replaceable></term>
-  
+
     <listitem><para>The path in the Nix store of the derivation from
     which <replaceable>outPath</replaceable> was built.  Not currently
     used.</para></listitem>
@@ -176,17 +175,21 @@ The elements are as follows:
   </varlistentry>
 
   <varlistentry><term><replaceable>outPath</replaceable></term>
-  
-    <listitem><para>The path in the Nix store of the package.  After
-    <command>nix-install-package</command> has obtained the manifest
-    from <replaceable>manifestURL</replaceable>, it performs a
-    <literal>nix-env -i</literal> <replaceable>outPath</replaceable>
-    to install the binary package.</para></listitem>
+
+    <listitem><para>The path in the Nix store of the
+    package.</para></listitem>
+
+  </varlistentry>
+
+  <varlistentry><term><replaceable>binaryCacheURL</replaceable></term>
+
+    <listitem><para>The URL of a binary cache containing the closure
+    of <replaceable>outPath</replaceable>.</para></listitem>
 
   </varlistentry>
 
 </variablelist>
-  
+
 </para>
 
 <para>An example follows: