How to Create an Explicitly Bound Socket

This topic describes how create an explicitly bound socket.

Start the network interface connection with RConnection::Start() to create an explicitly bound socket.

Creating an explicitly bound socket

Explicitly bound sockets can be created in two ways:

  1. Open a socket and bind the socket to a network interface connection.
  2. Open a socket and bind the socket to an IP address of the network interface connection.
    • Call RSocket::Bind() and bind the socket to an IP address of the network interface connection.

      RSocket::Bind() binds the socket to a unique IP address of the network interface connection.

      The following example code shows how to open a socket and bind the socket to a unique IP address of the WiFi connection.

      // open an implicit socket
      TInt err = iRecvSock.Open( iSs, KAfInet, KSockDatagram, KProtocolInetUdp); 
      User::LeaveIfError( err );
      // This IP address maps to WiFi in the ced.cfg file
      _LIT(KRasAddr,"192.168.220.4");
      const TInt KPort = 7000;
      TInetAddr addr;
      err = addr.Input( KRasAddr ); 
      User::LeaveIfError( err );
      addr.SetPort( KPort );
      // Now the socket is explicitly bound to WiFi  
      err = iRecvSock.Bind( addr ); 
      RDebug::Print( _L("testapp: ETH Bind() = %d"), err ); 
      User::LeaveIfError( err );
      

    The following code block shows an extract from the ced.cfg file.

    ## 
    [LANService]
    ADD_SECTION
    # COMMDB_ID = 1
    Name=Ethernet
    IfNetworks=ip
    IpNetMask=255.0.0.0
    IpGateway=0.0.0.0
    IpAddrFromServer=FALSE
    IpAddr=192.168.1.1
    IpDNSAddrFromServer=FALSE
    ConfigDaemonManagerName=NetCfgExtnDhcp
    ConfigDaemonName=!DhcpServ
    FIELD_COUNT=9
    END_ADD
    
    ADD_SECTION
    # COMMDB_ID = 2
    Name=Ethernet WiFi
    IfNetworks=ip
    IpNetMask=255.0.0.0
    IpGateway=0.0.0.0
    IpAddrFromServer=FALSE
    -// This IP address maps to WiFi
    IpAddr=192.168.220.4
    IpDNSAddrFromServer=FALSE
    IpNameServer1=194.72.6.51
    IpNameServer2=194.72.6.52
    ConfigDaemonManagerName=NetCfgExtnDhcp
    ConfigDaemonName=!DhcpServ
    LanServiceExtensionTableName=WLANServiceExtensionTable
    LanServiceExtensionTableRecordId=4
    FIELD_COUNT=13
    END_ADD
    

The socket is explicitly bound to the specific IP address of the network interface connection.

Explicit binding example

Client A creates a socket with explicit binding using the specified interface connection.

sock1 = RSocket.Open(srv,conn);

ESock creates the socket within the default connection and subconnection.

A socket can also be opened over a sub-connection using RSubConnection. When the socket is opened, a new Service Access Point (SAP) is created for the socket in ESock. The SAP is used to handle inbound and outbound data.