IrSock Client Application (Windows CE 5.0)
The basic procedure for using IrSock is similar to that for Winsock. IrSock uses only the stream socket connection-oriented communication method.
To create and use a socket with a client application
- Open a stream socket with socket, as with the server application. Use AF_IRDA for the address format parameter, SOCK_STREAM for the type and NULL for the protocol parameter
- Search for the available devices, and retrieve its address with getsockopt. For more information, see Discovering Devices Using IrSock.
- Connect to the server with the connect function using SOCKADDR_IRDA for the name parameter.
- Use send and recv to communicate with the server.
- Close the socket with closesocket.
For information about creating a server application, see IrSock Server Application
The following code sample shows how an IrSock client opens a socket and makes five attempts to locate a server. If no server is found, the client displays a dialog box to inform the user of the failure. When a server is detected, the client queries the server for its device identifier and sends a greeting to the service named My Server. It then waits for the server to respond, displays a message box with the response, and closes the socket.
#include <windows.h>
#include <af_irda.h>
#define NUMRETYR 5 // Maximum number of retries
int WINAPI WinMain (
HINSTANCE hInstance, // Handle to the current instance
HINSTANCE hPrevInstance,// Handle to the previous instance
LPTSTR lpCmdLine, // Pointer to the command line
int nCmdShow) // Show window state.
{
SOCKET sock; // Socket bound to the server
DEVICELIST devList; // Device list
SOCKADDR_IRDA address = {AF_IRDA, 0, 0, 0, 0, "IRServer"};
// Specifies the server socket address
int iCount = 0, // Number of retries
index = 0, // Integer index
iReturn, // Return value of recv function
iDevListLen = sizeof (devList);
// Size of the device list
char szClientA[100]; // ASCII string
TCHAR szClientW[100]; // Unicode string
TCHAR szError[100]; // Error message string
// Create a socket that is bound to the server.
if ((sock = socket (AF_IRDA, SOCK_STREAM, 0)) == INVALID_SOCKET)
{
wsprintf (szError, TEXT("Allocating socket failed. Error: %d"),
WSAGetLastError ());
MessageBox (NULL, szError, TEXT("Error"), MB_OK);
return FALSE;
}
// Initialize the number of devices to zero.
devList.numDevice = 0;
while ( (devList.numDevice == 0) && (iCount <= NUMRETYR))
{
// Retrieve the socket option.
if (getsockopt (sock, SOL_IRLMP, IRLMP_ENUMDEVICES,
(char *)&devList, &iDevListLen) == SOCKET_ERROR)
{
wsprintf (szError, TEXT("Server could not be located, getsockopt")
TEXT(" failed. Error: %d"), WSAGetLastError ());
MessageBox (NULL, szError, TEXT("Error"), MB_OK);
closesocket (sock);
return FALSE;
}
iCount++;
// Wait one second before retrying.
Sleep (1000);
}
if (iCount > NUMRETYR)
{
MessageBox (NULL, TEXT ("Server could not be located!"),
TEXT ("Error"), MB_OK);
closesocket (sock);
return FALSE;
}
// Get the server socket address.
for (index = 0; index <= 3; index++)
{
address.irdaDeviceID[index] = devList.Device[0].irdaDeviceID[index];
}
// Establish a connection to the socket.
if (connect (sock, (struct sockaddr *)&address,
sizeof (SOCKADDR_IRDA)) == SOCKET_ERROR)
{
wsprintf (szError,
TEXT("Connecting to the server failed. Error: %d"),
WSAGetLastError ());
MessageBox (NULL, szError, TEXT("Error"), MB_OK);
closesocket (sock);
return FALSE;
}
// Send a string from the client socket to the server socket.
if (send (sock, "To Server.", strlen ("To Server.") + 1, 0)
== SOCKET_ERROR)
{
wsprintf (szError,
TEXT("Sending data to the server failed. Error: %d"),
WSAGetLastError ());
MessageBox (NULL, szError, TEXT("Error"), MB_OK);
}
// Receive data from the server socket.
iReturn = recv (sock, szClientA, sizeof (szClientA), 0);
// Check if there is any data received. If there is, display it.
if (iReturn == SOCKET_ERROR)
{
wsprintf (szError, TEXT("No data is received, recv failed.")
TEXT(" Error: %d"), WSAGetLastError ());
MessageBox (NULL, szError, TEXT("Client"), MB_OK);
}
else if (iReturn == 0)
{
MessageBox (NULL, TEXT("Finished receiving data"), TEXT("Client"),
MB_OK);
}
else
{
// Convert the ASCII string to a Unicode string
szServerA[99] = 0;
MultiByteToWideChar(CP_ACP, 0, szServerA, -1,
szServerW, sizeof(szServerW)/sizeof(szServerW[0]));
// Display the string received from the server.
MessageBox (NULL, szClientW, TEXT("Received From Server"), MB_OK);
}
// Close the socket.
closesocket (sock);
return 0;
}
See Also
IrSock Server Application | Creating an Infrared Winsock Application | IrDA Application Development
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