gentoo-overlay/dev-libs/openct/metadata.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE pkgmetadata SYSTEM "http://www.gentoo.org/dtd/metadata.dtd">
<pkgmetadata>
  <herd>crypto</herd>
  <use>
    <flag name="pcsc-lite">
      Build a driver library for <pkg>sys-apps/pcsc-lite</pkg>,
      providing PC/SC API access to devices supported by OpenCT.
    </flag>

    <flag name="debug">
      Add debug output to the driver library for pcsc-lite.
    </flag>

    <flag name="udev">
      Install rules for <pkg>sys-fs/udev</pkg> to auto-start openct.
    </flag>
  </use>
</pkgmetadata>