(MFC) Bind and Listen on a Randomly Selected Unused Port

Demonstrates how to bind and listen on a randomly selected unused port.

Note:The ListenPort property used in this example is available starting in Chilkat v9.5.0.59.

Chilkat C/C++ Library Downloads MS Visual C/C++ Libs

See Also: Using MFC CString in Chilkat

#include <CkSocket.h>

void ChilkatSample(void)
    {
    CkString strOut;

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    CkSocket listenSocket;

    // Pass a value of 0 for the port number to randomly select
    // an unused port.
    // (The 2nd argument allows for a backlog of 25 pending connection requests when accepting connections.)
    bool success = listenSocket.BindAndListen(5555,25);
    if (success != true) {
        strOut.append(listenSocket.lastErrorText());
        strOut.append("\r\n");
        SetDlgItemText(IDC_EDIT1,strOut.getUnicode());
        return;
    }

    // Find out what port was chosen.
    // Note: The ListenPort propety was added in Chilkat v9.5.0.59
    int listenPort = listenSocket.get_ListenPort();
    strOut.append("Chosen listen port = ");
    strOut.appendInt(listenPort);
    strOut.append("\r\n");


    SetDlgItemText(IDC_EDIT1,strOut.getUnicode());

    }