RWSocketPortal
When you use the Essential Networking Module, you are usually either connecting to a remote server as a client, or waiting for remote clients to connect to you as a server. For either task, you use RWSocketPortal. We already used
RWSocketPortal when connecting to a remote server in
A Simple Code Example. Here's another example:
RWSocketPortal sp(RWInetAddr(80, "www.roguewave.com")); //1
In
//1, we create a connection to
www.roguewave.com, port
80, using class
RWSocketPortal. Notice that we initialize the
RWSocketPortal with an
RWInetAddr object.
RWInetAddr encapsulates an Internet address and can be constructed using a port and a host, as shown here.
Once we have created the connection using
RWSocketPortal, it can work with the familiar C++ iostreams to send and receive data. Let’s continue the example:
RWSocketPortal sp(RWInetAddr(80, "www.roguewave.com")); //1
RWPortalIStream istr(sp); //2
RWPortalOStream os(sp); //3
os << "GET / HTTP/1.0\r\n" << flush; //4
while(istr.good()) { //5
RWCString data;
data.readLine(istr);
cout << data << flush;
}
On
//2 and
//3, we use
RWPortalIStream and
RWPortalOStream to give us a high-level iostream interface to our network connection. These classes derive from
istream and
ostream, respectively, and can be used anywhere a standard iostream is used.
On
//4, we write our HTTP request. Finally, in the
while loop beginning on
//5, we read each line of the response using
RWCString::readLine(), a member function that reads a line from the given stream into the
RWCString, and echo it to
cout. That’s all there is to it. Of course, we could write an even simpler version of this program by using the prebuilt HTTP classes in the Internet Protocols Module, but this example shows how easy it is to use classes of the Essential Networking Module alone. For more information on transferring data using streams, see
Chapter 5, Streams.
