iproute2 question

i am trying to send "iproute2 get" requests in async fashion to the
kernel.....i mean i send a new request to get new route even before i have
response to the earlier request...the "route get" implementation in iproute2
library is synchronous...it uses "rtnl_talk" routine and works great...i am
breaking it up for my application into "rtnl_send" and "rtnl_recv" for async
operation.....but it looks like i dont get responses for some of my
requests....any clues ?????