logic for checking what is the input data

can any one help me开发者_开发百科 in this logic, when i enter a source ip is should call a particular function XXX()if i enter destination ip or destination port or source port it should call a different function say YYY(), my doubt is how can i recognise whether the input address is source ip address or destination address

With assumption that you are referring to Command Line Arguments. You should have options to your program. For example :

program_name --source-ip <source ip> --source-port <source-port> --destination-ip <destination-ip> --destination-port <destination-port>

You should then parse those and call the functions accordingly.