<chapter 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-env-variables">

<title>Environment Variables</title>

<para>To use Nix, some environment variables should be set.  In
particular, <envar>PATH</envar> should contain the directories
<filename><replaceable>prefix</replaceable>/bin</filename> and
<filename>~/.nix-profile/bin</filename>.  The first directory contains
the Nix tools themselves, while <filename>~/.nix-profile</filename> is
a symbolic link to the current <emphasis>user environment</emphasis>
(an automatically generated package consisting of symlinks to
installed packages).  The simplest way to set the required environment
variables is to include the file
<filename><replaceable>prefix</replaceable>/etc/profile.d/nix.sh</filename>
in your <filename>~/.profile</filename> (or similar), like this:</para>

<screen>
source <replaceable>prefix</replaceable>/etc/profile.d/nix.sh</screen>

</chapter>