Hello,
I'm trying to call the function GetInterfaceInfo of iphlpapi.dll/runtimes of D, and it didn't work.
I don't know how to call it, or what parameters I should put in. I checked the Microsoft Windows APIs, the D documentation of the function, and still, don't succeed.
Can someone please explain me with an example how to use it?

On Thursday, 8 June 2023 at 05:29:07 UTC, Benny wrote:

Hi!

it would be nice to see the code

it would be nice to see specifics (error code, results, etc)

On Thursday, 8 June 2023 at 05:42:20 UTC, novice2 wrote:

import core.sys.windows.iphlpapi;
import std.stdio;

void main()
{
	auto h = GetInterfaceInfo(null, null);
	writeln("Hello, World!");
}

app.obj : error LNK2019: unresolved external symbol GetInterfaceInfo referenced in function _Dmain
app.exe : fatal error LNK1120: 1 unresolved externals
Error: linker exited with status 1120

On Thursday, 8 June 2023 at 05:52:43 UTC, Benny wrote:

That's a linker error telling you that you aren't linking anything that contains the symbol for GetInterfaceInfo. You need to link Iphlpapi.lib.

On Thursday, 8 June 2023 at 06:22:08 UTC, Mike Parker wrote:

I got something! thank you.
now I need to understand how can I get the properties of the GetInterfaceInfo

import core.sys.windows.iphlpapi;
import std.stdio;
import core.stdc.stdlib;

    void main()
    {
    	uint* i;
    	i = cast(uint*) malloc(10);
    	auto h = GetInterfaceInfo(null, i);
    	writefln("%s", h);
    	writeln("Hello, World!");
    }

this got me 122

On Thursday, 8 June 2023 at 07:01:44 UTC, Benny wrote:

import core.sys.windows.iphlpapi;
import std.stdio;
import core.stdc.stdlib;

    void main()
    {
    	uint* i;
    	i = cast(uint*) malloc(10);
    	auto h = GetInterfaceInfo(null, i);
    	writefln("%s", h);
    	writeln("Hello, World!");
    }

Alright. I've never used this function, so I referenced the documentation here:

https://learn.microsoft.com/en-us/windows/win32/api/iphlpapi/nf-iphlpapi-getinterfaceinfo

First, you don't need to allocate i with malloc. Just declare it as a uint and give the function a pointer to it.

Second, the function is intended to be called twice. The first time with null for the first parameter as you've done here. After that call, the value in i should be the size of the memory you need to allocate for the first parameter on the second call. In the second call, the data you want will be stored in that pointer.

Third, the first parameter is of type PIP_INTERACE_INFO, which in Windows lingo means "pointer to IP_INTERFACE_INFO". That's declared in the ipexport module.

Here's a working example. I chose to use the GC rather than malloc.

import core.sys.windows.windows,  // For the error codes
       core.sys.windows.iphlpapi,
       core.sys.windows.ipexport;

import std.stdio,
       std.string;

void main()
{

    IP_INTERFACE_INFO* pinfo;
    uint buflen;

    // Get the size needed to alloc pinfo
    uint ret = GetInterfaceInfo(null, &buflen);
    if(ret == ERROR_INSUFFICIENT_BUFFER) {
        // Allocate pinfo, but let's not use malloc
        ubyte[] buf = new ubyte[](buflen);
        pinfo = cast(IP_INTERFACE_INFO*)buf.ptr;
    }

    // Call the function a second time to get the data
    ret = GetInterfaceInfo(pinfo, &buflen);
    if(ret == NO_ERROR) {
        writeln("Number of adapters: ", pinfo.NumAdapters);
        for(size_t i = 0; i<pinfo.NumAdapters; ++i) {
            writefln("Adapter Index[%s]: %s", i, pinfo.Adapter[i].Index);
            writefln("Adapter Index[%s]: %s", i, fromStringz(pinfo.Adapter[i].Name));
        }
    }
    else if(ret == ERROR_NO_DATA) {
        writeln("No network adapters found");
    }
    else {
        writeln("GetInterfaceInfo failure: ", ret);
    }
}

On Thursday, 8 June 2023 at 07:01:44 UTC, Benny wrote:

don be shy, try to do something yourself, be curiosity!
use C:\Program Files\Microsoft Visual Studio\2022\Community\Common7\Tools\errlook.exe
or
https://learn.microsoft.com/en-us/windows/win32/debug/system-error-codes--0-499-
to find what means some error code