Hello.

I am implementing UDP communication with other system, QNX is to be server in the communication waiting for requests 
from clients.

The "server" is supposed to be in "standby" mode, so the active one of the two servers will have assigned IP alias. 
Clients will send UDP packets to the alias IP.

So far, so good.

The server is able to receive packet via recvmsg(), via msghdr and IP_RECVDSTADDR I am able to find which interface 
received the packet.

But the hard part is to send the packet from given IP address.

According to information in Internet one should use either IP_SENDSRCADDR or IP_PKTINFO in msghdr in sendmsg, but none 
of these is defined in QNX.

Is there any way to accomplish what I need to?

Thank you.