DhcpEnumClassesV6

// DHCPSAPI.dll
#include <windows.h>

DWORD DhcpEnumClassesV6(
    LPWSTR ServerIpAddress,   // optional
    DWORD ReservedMustBeZero,
    DWORD* ResumeHandle,
    DWORD PreferredMaximum,
    DHCP_CLASS_INFO_ARRAY_V6** ClassInfoArray,
    DWORD* nRead,
    DWORD* nTotal
);

<DllImport("DHCPSAPI.dll", ExactSpelling:=True)>
Public Shared Function DhcpEnumClassesV6(
    <MarshalAs(UnmanagedType.LPWStr)> ServerIpAddress As String,   ' LPWSTR optional
    ReservedMustBeZero As UInteger,   ' DWORD
    ByRef ResumeHandle As UInteger,   ' DWORD* in/out
    PreferredMaximum As UInteger,   ' DWORD
    ClassInfoArray As IntPtr,   ' DHCP_CLASS_INFO_ARRAY_V6** in/out
    ByRef nRead As UInteger,   ' DWORD* in/out
    ByRef nTotal As UInteger   ' DWORD* in/out
) As UInteger
End Function

' ServerIpAddress : LPWSTR optional
' ReservedMustBeZero : DWORD
' ResumeHandle : DWORD* in/out
' PreferredMaximum : DWORD
' ClassInfoArray : DHCP_CLASS_INFO_ARRAY_V6** in/out
' nRead : DWORD* in/out
' nTotal : DWORD* in/out
Declare PtrSafe Function DhcpEnumClassesV6 Lib "dhcpsapi" ( _
    ByVal ServerIpAddress As LongPtr, _
    ByVal ReservedMustBeZero As Long, _
    ByRef ResumeHandle As Long, _
    ByVal PreferredMaximum As Long, _
    ByVal ClassInfoArray As LongPtr, _
    ByRef nRead As Long, _
    ByRef nTotal As Long) As Long
' VBA7前提(PtrSafe)。32bit Office では LongPtr→Long。Integer=16bit / Long=32bit / LongLong=64bit。

import ctypes
from ctypes import wintypes

DhcpEnumClassesV6 = ctypes.windll.dhcpsapi.DhcpEnumClassesV6
DhcpEnumClassesV6.restype = wintypes.DWORD
DhcpEnumClassesV6.argtypes = [
    wintypes.LPCWSTR,  # ServerIpAddress : LPWSTR optional
    wintypes.DWORD,  # ReservedMustBeZero : DWORD
    ctypes.POINTER(wintypes.DWORD),  # ResumeHandle : DWORD* in/out
    wintypes.DWORD,  # PreferredMaximum : DWORD
    ctypes.c_void_p,  # ClassInfoArray : DHCP_CLASS_INFO_ARRAY_V6** in/out
    ctypes.POINTER(wintypes.DWORD),  # nRead : DWORD* in/out
    ctypes.POINTER(wintypes.DWORD),  # nTotal : DWORD* in/out
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('DHCPSAPI.dll')
DhcpEnumClassesV6 = Fiddle::Function.new(
  lib['DhcpEnumClassesV6'],
  [
    Fiddle::TYPE_VOIDP,  # ServerIpAddress : LPWSTR optional
    -Fiddle::TYPE_INT,  # ReservedMustBeZero : DWORD
    Fiddle::TYPE_VOIDP,  # ResumeHandle : DWORD* in/out
    -Fiddle::TYPE_INT,  # PreferredMaximum : DWORD
    Fiddle::TYPE_VOIDP,  # ClassInfoArray : DHCP_CLASS_INFO_ARRAY_V6** in/out
    Fiddle::TYPE_VOIDP,  # nRead : DWORD* in/out
    Fiddle::TYPE_VOIDP,  # nTotal : DWORD* in/out
  ],
  -Fiddle::TYPE_INT)

#[link(name = "dhcpsapi")]
extern "system" {
    fn DhcpEnumClassesV6(
        ServerIpAddress: *mut u16,  // LPWSTR optional
        ReservedMustBeZero: u32,  // DWORD
        ResumeHandle: *mut u32,  // DWORD* in/out
        PreferredMaximum: u32,  // DWORD
        ClassInfoArray: *mut *mut DHCP_CLASS_INFO_ARRAY_V6,  // DHCP_CLASS_INFO_ARRAY_V6** in/out
        nRead: *mut u32,  // DWORD* in/out
        nTotal: *mut u32  // DWORD* in/out
    ) -> u32;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("DHCPSAPI.dll")]
public static extern uint DhcpEnumClassesV6([MarshalAs(UnmanagedType.LPWStr)] string ServerIpAddress, uint ReservedMustBeZero, ref uint ResumeHandle, uint PreferredMaximum, IntPtr ClassInfoArray, ref uint nRead, ref uint nTotal);
"@
$api = Add-Type -MemberDefinition $sig -Name 'DHCPSAPI_DhcpEnumClassesV6' -Namespace Win32 -PassThru
# $api::DhcpEnumClassesV6(ServerIpAddress, ReservedMustBeZero, ResumeHandle, PreferredMaximum, ClassInfoArray, nRead, nTotal)

#uselib "DHCPSAPI.dll"
#func global DhcpEnumClassesV6 "DhcpEnumClassesV6" sptr, sptr, sptr, sptr, sptr, sptr, sptr
; DhcpEnumClassesV6 ServerIpAddress, ReservedMustBeZero, varptr(ResumeHandle), PreferredMaximum, varptr(ClassInfoArray), varptr(nRead), varptr(nTotal)   ; 戻り値は stat
; ServerIpAddress : LPWSTR optional -> "sptr"
; ReservedMustBeZero : DWORD -> "sptr"
; ResumeHandle : DWORD* in/out -> "sptr"
; PreferredMaximum : DWORD -> "sptr"
; ClassInfoArray : DHCP_CLASS_INFO_ARRAY_V6** in/out -> "sptr"
; nRead : DWORD* in/out -> "sptr"
; nTotal : DWORD* in/out -> "sptr"
; ※HSP3.7は #func のため戻り値はシステム変数 stat に格納されます。

#uselib "DHCPSAPI.dll"
#cfunc global DhcpEnumClassesV6 "DhcpEnumClassesV6" wstr, int, var, int, var, var, var
; res = DhcpEnumClassesV6(ServerIpAddress, ReservedMustBeZero, ResumeHandle, PreferredMaximum, ClassInfoArray, nRead, nTotal)
; ServerIpAddress : LPWSTR optional -> "wstr"
; ReservedMustBeZero : DWORD -> "int"
; ResumeHandle : DWORD* in/out -> "var"
; PreferredMaximum : DWORD -> "int"
; ClassInfoArray : DHCP_CLASS_INFO_ARRAY_V6** in/out -> "var"
; nRead : DWORD* in/out -> "var"
; nTotal : DWORD* in/out -> "var"
; ※出力/バッファ引数は var 方式(変数を直接渡す)。varptr 方式にも切替可。

; DWORD DhcpEnumClassesV6(LPWSTR ServerIpAddress, DWORD ReservedMustBeZero, DWORD* ResumeHandle, DWORD PreferredMaximum, DHCP_CLASS_INFO_ARRAY_V6** ClassInfoArray, DWORD* nRead, DWORD* nTotal)
#uselib "DHCPSAPI.dll"
#cfunc global DhcpEnumClassesV6 "DhcpEnumClassesV6" wstr, int, var, int, var, var, var
; res = DhcpEnumClassesV6(ServerIpAddress, ReservedMustBeZero, ResumeHandle, PreferredMaximum, ClassInfoArray, nRead, nTotal)
; ServerIpAddress : LPWSTR optional -> "wstr"
; ReservedMustBeZero : DWORD -> "int"
; ResumeHandle : DWORD* in/out -> "var"
; PreferredMaximum : DWORD -> "int"
; ClassInfoArray : DHCP_CLASS_INFO_ARRAY_V6** in/out -> "var"
; nRead : DWORD* in/out -> "var"
; nTotal : DWORD* in/out -> "var"
; ※出力/バッファ引数は var 方式(変数を直接渡す)。varptr 方式にも切替可。

import (
	"golang.org/x/sys/windows"
	"unsafe"
)

var (
	dhcpsapi = windows.NewLazySystemDLL("DHCPSAPI.dll")
	procDhcpEnumClassesV6 = dhcpsapi.NewProc("DhcpEnumClassesV6")
)

// ServerIpAddress (LPWSTR optional), ReservedMustBeZero (DWORD), ResumeHandle (DWORD* in/out), PreferredMaximum (DWORD), ClassInfoArray (DHCP_CLASS_INFO_ARRAY_V6** in/out), nRead (DWORD* in/out), nTotal (DWORD* in/out)
r1, _, err := procDhcpEnumClassesV6.Call(
	uintptr(unsafe.Pointer(windows.StringToUTF16Ptr(ServerIpAddress))),
	uintptr(ReservedMustBeZero),
	uintptr(ResumeHandle),
	uintptr(PreferredMaximum),
	uintptr(ClassInfoArray),
	uintptr(nRead),
	uintptr(nTotal),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // DWORD

function DhcpEnumClassesV6(
  ServerIpAddress: PWideChar;   // LPWSTR optional
  ReservedMustBeZero: DWORD;   // DWORD
  ResumeHandle: Pointer;   // DWORD* in/out
  PreferredMaximum: DWORD;   // DWORD
  ClassInfoArray: Pointer;   // DHCP_CLASS_INFO_ARRAY_V6** in/out
  nRead: Pointer;   // DWORD* in/out
  nTotal: Pointer   // DWORD* in/out
): DWORD; stdcall;
  external 'DHCPSAPI.dll' name 'DhcpEnumClassesV6';

result := DllCall("DHCPSAPI\DhcpEnumClassesV6"
    , "WStr", ServerIpAddress   ; LPWSTR optional
    , "UInt", ReservedMustBeZero   ; DWORD
    , "Ptr", ResumeHandle   ; DWORD* in/out
    , "UInt", PreferredMaximum   ; DWORD
    , "Ptr", ClassInfoArray   ; DHCP_CLASS_INFO_ARRAY_V6** in/out
    , "Ptr", nRead   ; DWORD* in/out
    , "Ptr", nTotal   ; DWORD* in/out
    , "UInt")   ; return: DWORD

●DhcpEnumClassesV6(ServerIpAddress, ReservedMustBeZero, ResumeHandle, PreferredMaximum, ClassInfoArray, nRead, nTotal) = DLL("DHCPSAPI.dll", "dword DhcpEnumClassesV6(char*, dword, void*, dword, void*, void*, void*)")
# 呼び出し: DhcpEnumClassesV6(ServerIpAddress, ReservedMustBeZero, ResumeHandle, PreferredMaximum, ClassInfoArray, nRead, nTotal)
# ServerIpAddress : LPWSTR optional -> "char*"
# ReservedMustBeZero : DWORD -> "dword"
# ResumeHandle : DWORD* in/out -> "void*"
# PreferredMaximum : DWORD -> "dword"
# ClassInfoArray : DHCP_CLASS_INFO_ARRAY_V6** in/out -> "void*"
# nRead : DWORD* in/out -> "void*"
# nTotal : DWORD* in/out -> "void*"
# なでしこ1は32bit・ANSI(Shift_JIS)。文字列=char*(ANSI)、ポインタ/ハンドル=void*(4byte)。