CRMCLink::Disconnect Method

Closes the connection associated with this CRMCLink object, if one has been established.

Syntax

C++

void Disconnect();

Remarks

On serial connections, the serial port will be released for use by other applications. On Ethernet connection, the TCP/IP connection will be closed.

This method is synchronous, which means that it will not return until the link is disconnected. However, disconnecting generally takes only a fraction of a second.

WARNING: For Ethernet connections, it is highly recommended that the connection not be disconnected and re-connected between transactions. Doing so will have lower performance, and more importantly, each call to Connect() will consume a TCP connection in the Windows operating system. This TCP connection will not be fully released by the operating system until typically 2 minutes after Disconnect() is called. Therefore, it is possible to consume all available TCP connections by repeated calls to Connect()/Disconnect() and as a result be unable to re-connect over RMCLink or even adversely affect other applications running on the same PC.

Example

The following code example illustrates the use of the Disconnect method.

C++

#include <windows.h>
#include <stdio.h>
#include "RMCLink.h"
 
void main()
{
    // In order to create COM objects, we must initialize the COM sub-system.
    ::CoInitialize(0);
 
    // Create a new RMCLink object.
    CRMCLink* pRMC = CRMCLink::CreateEthernetLink(CRMCLink::dtRMC70, _T("192.168.0.22"));
    if ( pRMC != NULL )
    {
        // Establish the connection.
        HRESULT hr = pRMC->Connect();
        if ( SUCCEEDED(hr) )
        {
            // Read F8:8 and F8:9 (Axis 0 Actual Position and Velocity)
            float afData[2];
            hr = pRMC->ReadFFile(CRMCLink::fn70StatusAxis0, 8, 2, afData);
            if ( SUCCEEDED(hr) )
            {
                printf("Actual Position = %.3f, Actual Velocity = %.3f\n",
                    afData[0], afData[1]);
            }
 
            // Close the connection.
            pRMC->Disconnect();
        }
 
        // Free the RMCLink object we created.
        delete pRMC;
    }
 
    // Release the COM sub-system.
    ::CoUninitialize();
}