get_implementation_indices() {
local ret n
for (( n = 0; n < ${#XVMCLIBS[@]}; ++n )); do
[[ -e "${ROOT}/usr/lib/${XVMCLIBS[n]}" ]] && ret+=($n)
[[ -e "${ROOT}/usr/lib/${XVMCLIBS[n]##*/}" ]] && ret+=($n)
done
echo ${ret[@]}