I'm writting a server program, don't know how far I'll get but I'm giving it a try. What I need to do is open a new port for each user (connection). How, programaticly, do I check if a certain ...

System and network troubleshooting often involves checking and obtaining information about ports to ensure functionality and determine the source of problems. Learn handy tips to help keep systems ...

You could try telneting to port 139 from an outside machine. If you get anything other than an access denied, you likely have an open port.