<fontconfig>

  <alias>

    <family>Khmer OS Content</family>

    <default>

      <family>monospace</family>

    </default>

  </alias>

  <match>

    <test name="lang" compare="contains">

      <string>km</string>

    </test>

    <test name="family">

      <string>monospace</string>

    </test>

    <edit name="family" mode="prepend">

      <string>Khmer OS Content</string>

    </edit>

  </match>

</fontconfig>