Prerequisite: Socket programming in C/C++.
In socket programming, when server and client are connected then client is provided any random port number by operating system to run and generally, we don’t care about it, But in some cases, there may be a firewall on the client side that only allows outgoing connections on certain port numbers. So, it is highly probable that the port number provided to client by operating system may have been blocked by client firewall. In that case, we need to explicitly or forcefully assign any port number to the client on which it can operate.
Some protocol like NFS protocol requires client program to run on only certain port number and so in this case, client need to forcefully assigned that port number only as it runs on port number either on 111 or on 2049. This can be done using bind() system call with specifying particular port number in client side socket.
Below is the implementation Server and Client program where client will be forcefully get assigned a port number.
Server Side Program
Server Created Binded Correctly Listening ... Connection Established connection established with IP : 10.32.40.213 and PORT : 12010 Client : Hello
Client Side Program
Client Created Binded Correctly Client Connected Server : Hello
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