What is the OSStatus error -9800?

In my iOS application using Bonjour i am listing out all networks with specific service type. Connecting one of the network by socket. Actually while sending text message to particular mac system(one of them on list) by NSStreamDelegate. Once the NSStreamEventOpenCompleted is Opened it through an error like

"error is Error Domain=NSOSStatusErrorDomain. The operation couldn’t be completed. (OSStatus error -9800.)" .

What is the actual problem?