Server and client running in same app on same socket

Server and client running in same app on same socket

I have a client and server running in the same app, server's thread is
always running to listen for the data, but when the client has to send the
data and it creates its own thread my app crashes because it also tries to
bind the socket on the same port on which server is listening, I have no
other choice other than to use the same port on client and server.How to
tackle this problem,and how can I send and receive on the same port with
two different sockets? Please help....