Network Management

Posted by TechGuru on Sep 10, 2025

The Network Management section of the Win32 API provides developers with a set of functions to configure, monitor, and control network interfaces, routes, and protocols on a Windows system. This article covers the most commonly used functions, structures, and best practices.

Key Functions

GetIfTable – Retrieves a list of network interfaces.
GetAdaptersAddresses – Provides detailed information about each adapter.
AddIPAddress – Assigns a new IP address to a specific interface.
DeleteIPAddress – Removes an IP address from an interface.
SetIfEntry – Modifies the operational state of an interface.

Example: Enumerating Network Interfaces

#include <windows.h>
#include <iphlpapi.h>
#pragma comment(lib, "iphlpapi.lib")

int main() {
    DWORD size = 0;
    GetIfTable(NULL, &size, FALSE); // get required size
    MIB_IFTABLE *iftable = (MIB_IFTABLE*)malloc(size);
    if (GetIfTable(iftable, &size, FALSE) == NO_ERROR) {
        for (DWORD i = 0; i < iftable->dwNumEntries; ++i) {
            MIB_IFROW *row = &iftable->table[i];
            wprintf(L"%s (Index: %lu) - %lu bytes sent\\n",
                row->wszName, row->dwIndex, row->dwOutOctets);
        }
    }
    free(iftable);
    return 0;
}

This snippet demonstrates how to retrieve and display basic information about each network interface using GetIfTable.

Best Practices

Always check the return value of API calls for ERROR_INSUFFICIENT_BUFFER and allocate the necessary memory.
Prefer GetAdaptersAddresses over older functions for IPv6 compatibility.
When modifying interface state, ensure you have administrative privileges.
Use the SetIfEntry function carefully, as disabling an adapter can affect system connectivity.

Comments (2)

JaneDoe

Very helpful example! I used this to build a network monitor for my app.

MikeSmith

Remember to free the memory allocated for GetAdaptersAddresses as well.

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