C / C++ / MFC

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PMIB_IPFORWARDROW pRow = NULL;<br />
ULONG dwSize = 0;<br />
DWORD dwStatus = 0;<br />
<br />
// Allocate some memory to store the row in<br />
pRow = (PMIB_IPFORWARDROW)malloc(sizeof(MIB_IPFORWARDROW));<br />
<br />
if (!pRow) {<br />
MessageBox("Malloc failed, Out of Memory!\r\n");<br />
exit(1);<br />
}<br />
<br />
// changing dwForwardNextHop into anything else works...<br />
// 172.31.64.9 is the ip address assigned (through DHCP) to my ethernetcard.<br />
// route add 172.0.0.0 mask 255.0.0.0 172.31.64.9 metric 30 if 2<br />
// works just fine.<br />
pRow->dwForwardDest = inet_addr("172.0.0.0");<br />
pRow->dwForwardNextHop = inet_addr("172.31.64.9"); // --> this doesn't work, any other value does<br />
pRow->dwForwardMask = inet_addr("255.0.0.0");<br />
pRow->dwForwardIfIndex = 2;<br />
pRow->dwForwardType = 4;<br />
pRow->dwForwardProto = MIB_IPPROTO_NETMGMT;<br />
pRow->dwForwardAge = 0;<br />
pRow->dwForwardMetric1 = 30; <br />
<br />
// Create a new route entry for the default gateway.<br />
dwStatus = createipForwardEntry(pRow);<br />
<br />
if (dwStatus == NO_ERROR)<br />
MessageBox("Route Added Successfully\n");<br />
else if (dwStatus == ERROR_INVALID_PARAMETER)<br />
MessageBox("Invalid Parameter\n");<br />
else <br />
DisplayErrorMessage(dwStatus);<br />
<br />
// Free resources<br />
if (pRow)<br />
free(pRow); <br />