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    <h1><a id="installation">libvirt Installation</a></h1>

    <ul id="toc"></ul>

    <h2><a id="compiling">Compiling a release tarball</a></h2>

    <p>
      libvirt uses the standard configure/make/install steps:
    </p>

    <pre>
$ xz -c libvirt-x.x.x.tar.xz | tar xvf -
$ cd libvirt-x.x.x
$ ./configure</pre>

    <p>
      The <i>configure</i> script can be given options to change its default
      behaviour.
    </p>

    <p>
      To get the complete list of the options it can take, pass it the
      <i>--help</i> option like this:
    </p>

    <pre>
$ ./configure <i>--help</i></pre>

    <p>
      When you have determined which options you want to use (if any),
      continue the process.
    </p>

    <p>
      Note the use of <b>sudo</b> with the <i>make install</i> command
      below.  Using sudo is only required when installing to a location your
      user does not have write access to.  Installing to a system location
      is a good example of this.
    </p>

    <p>
      If you are installing to a location that your user <i>does</i> have write
      access to, then you can instead run the <i>make install</i> command
      without putting <b>sudo</b> before it.
    </p>

    <pre>
$ ./configure <i>[possible options]</i>
$ make
$ <b>sudo</b> <i>make install</i></pre>

    <p>
      At this point you <b>may</b> have to run ldconfig or a similar utility
      to update your list of installed shared libs.
    </p>

    <h2><a id="building">Building from a GIT checkout</a></h2>

    <p>
      The libvirt build process uses GNU autotools, so after obtaining a
      checkout it is necessary to generate the configure script and Makefile.in
      templates using the <code>autogen.sh</code> command. By default when
      the <code>configure</code> script is run from within a GIT checkout, it
      will turn on -Werror for builds. This can be disabled with
      --disable-werror, but this is not recommended.
    </p>
    <p>
      Libvirt takes advantage of
      the <a href="http://www.gnu.org/software/gnulib/">gnulib</a>
      project to provide portability to a number of platforms.  This
      is normally done dynamically via a git submodule in
      the <code>.gnulib</code> subdirectory, which is auto-updated as
      needed when you do incremental builds.  Setting the environment
      variable <code>GNULIB_SRCDIR</code> to a local directory
      containing a git checkout of gnulib will let you reduce local
      disk space requirements and network download time, regardless of
      which actual commit you have in that reference directory.
    </p>
    <p>
      However, if you are developing on a platform where git is not
      available, or are behind a firewall that does not allow for git
      to easily obtain the gnulib submodule, it is possible to instead
      use a static mode of operation where you are then responsible
      for updating the git submodule yourself.  In this mode, you must
      track the exact gnulib commit needed by libvirt (usually not the
      latest gnulib.git) via alternative means, such as a shared NFS
      drive or manual download, and run this any time libvirt.git
      updates the commit stored in the .gnulib submodule:</p>
    <pre>
$ GNULIB_SRCDIR=/path/to/gnulib ./autogen.sh --no-git
    </pre>

    <p>To build &amp; install libvirt to your home
      directory the following commands can be run:
    </p>

    <pre>
$ ./autogen.sh --prefix=$HOME/usr
$ make
$ <b>sudo</b> make install</pre>

    <p>
      Be aware though, that binaries built with a custom prefix will not
      interoperate with OS vendor provided binaries, since the UNIX socket
      paths will all be different. To produce a build that is compatible
      with normal OS vendor prefixes, use
    </p>

    <pre>
$ ./autogen.sh --system
$ make
    </pre>

    <p>
      When doing this for day-to-day development purposes, it is recommended
      not to install over the OS vendor provided binaries. Instead simply
      run libvirt directly from the source tree. For example to run
      a privileged libvirtd instance
    </p>

    <pre>
$ su -
# service libvirtd stop  (or systemctl stop libvirtd.service)
# /home/to/your/checkout/src/libvirtd
    </pre>

    <p>
      It is also possible to run virsh directly from the source tree
      using the ./run script (which sets some environment variables):
    </p>

    <pre>
$ ./run ./tools/virsh ....
    </pre>
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