DhcpGetClientOptions

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

DWORD DhcpGetClientOptions(
    LPCWSTR ServerIpAddress,   // optional
    DWORD ClientIpAddress,
    DWORD ClientSubnetMask,
    DHCP_OPTION_LIST** ClientOptions
);

<DllImport("DHCPSAPI.dll", ExactSpelling:=True)>
Public Shared Function DhcpGetClientOptions(
    <MarshalAs(UnmanagedType.LPWStr)> ServerIpAddress As String,   ' LPCWSTR optional
    ClientIpAddress As UInteger,   ' DWORD
    ClientSubnetMask As UInteger,   ' DWORD
    ClientOptions As IntPtr   ' DHCP_OPTION_LIST** in/out
) As UInteger
End Function

' ServerIpAddress : LPCWSTR optional
' ClientIpAddress : DWORD
' ClientSubnetMask : DWORD
' ClientOptions : DHCP_OPTION_LIST** in/out
Declare PtrSafe Function DhcpGetClientOptions Lib "dhcpsapi" ( _
    ByVal ServerIpAddress As LongPtr, _
    ByVal ClientIpAddress As Long, _
    ByVal ClientSubnetMask As Long, _
    ByVal ClientOptions As LongPtr) As Long
' VBA7前提(PtrSafe)。32bit Office では LongPtr→Long。Integer=16bit / Long=32bit / LongLong=64bit。

import ctypes
from ctypes import wintypes

DhcpGetClientOptions = ctypes.windll.dhcpsapi.DhcpGetClientOptions
DhcpGetClientOptions.restype = wintypes.DWORD
DhcpGetClientOptions.argtypes = [
    wintypes.LPCWSTR,  # ServerIpAddress : LPCWSTR optional
    wintypes.DWORD,  # ClientIpAddress : DWORD
    wintypes.DWORD,  # ClientSubnetMask : DWORD
    ctypes.c_void_p,  # ClientOptions : DHCP_OPTION_LIST** in/out
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('DHCPSAPI.dll')
DhcpGetClientOptions = Fiddle::Function.new(
  lib['DhcpGetClientOptions'],
  [
    Fiddle::TYPE_VOIDP,  # ServerIpAddress : LPCWSTR optional
    -Fiddle::TYPE_INT,  # ClientIpAddress : DWORD
    -Fiddle::TYPE_INT,  # ClientSubnetMask : DWORD
    Fiddle::TYPE_VOIDP,  # ClientOptions : DHCP_OPTION_LIST** in/out
  ],
  -Fiddle::TYPE_INT)

#[link(name = "dhcpsapi")]
extern "system" {
    fn DhcpGetClientOptions(
        ServerIpAddress: *const u16,  // LPCWSTR optional
        ClientIpAddress: u32,  // DWORD
        ClientSubnetMask: u32,  // DWORD
        ClientOptions: *mut *mut DHCP_OPTION_LIST  // DHCP_OPTION_LIST** in/out
    ) -> u32;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("DHCPSAPI.dll")]
public static extern uint DhcpGetClientOptions([MarshalAs(UnmanagedType.LPWStr)] string ServerIpAddress, uint ClientIpAddress, uint ClientSubnetMask, IntPtr ClientOptions);
"@
$api = Add-Type -MemberDefinition $sig -Name 'DHCPSAPI_DhcpGetClientOptions' -Namespace Win32 -PassThru
# $api::DhcpGetClientOptions(ServerIpAddress, ClientIpAddress, ClientSubnetMask, ClientOptions)

#uselib "DHCPSAPI.dll"
#func global DhcpGetClientOptions "DhcpGetClientOptions" sptr, sptr, sptr, sptr
; DhcpGetClientOptions ServerIpAddress, ClientIpAddress, ClientSubnetMask, varptr(ClientOptions)   ; 戻り値は stat
; ServerIpAddress : LPCWSTR optional -> "sptr"
; ClientIpAddress : DWORD -> "sptr"
; ClientSubnetMask : DWORD -> "sptr"
; ClientOptions : DHCP_OPTION_LIST** 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 DhcpGetClientOptions "DhcpGetClientOptions" wstr, int, int, var
; res = DhcpGetClientOptions(ServerIpAddress, ClientIpAddress, ClientSubnetMask, ClientOptions)
; ServerIpAddress : LPCWSTR optional -> "wstr"
; ClientIpAddress : DWORD -> "int"
; ClientSubnetMask : DWORD -> "int"
; ClientOptions : DHCP_OPTION_LIST** 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 DhcpGetClientOptions(LPCWSTR ServerIpAddress, DWORD ClientIpAddress, DWORD ClientSubnetMask, DHCP_OPTION_LIST** ClientOptions)
#uselib "DHCPSAPI.dll"
#cfunc global DhcpGetClientOptions "DhcpGetClientOptions" wstr, int, int, var
; res = DhcpGetClientOptions(ServerIpAddress, ClientIpAddress, ClientSubnetMask, ClientOptions)
; ServerIpAddress : LPCWSTR optional -> "wstr"
; ClientIpAddress : DWORD -> "int"
; ClientSubnetMask : DWORD -> "int"
; ClientOptions : DHCP_OPTION_LIST** 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")
	procDhcpGetClientOptions = dhcpsapi.NewProc("DhcpGetClientOptions")
)

// ServerIpAddress (LPCWSTR optional), ClientIpAddress (DWORD), ClientSubnetMask (DWORD), ClientOptions (DHCP_OPTION_LIST** in/out)
r1, _, err := procDhcpGetClientOptions.Call(
	uintptr(unsafe.Pointer(windows.StringToUTF16Ptr(ServerIpAddress))),
	uintptr(ClientIpAddress),
	uintptr(ClientSubnetMask),
	uintptr(ClientOptions),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // DWORD

function DhcpGetClientOptions(
  ServerIpAddress: PWideChar;   // LPCWSTR optional
  ClientIpAddress: DWORD;   // DWORD
  ClientSubnetMask: DWORD;   // DWORD
  ClientOptions: Pointer   // DHCP_OPTION_LIST** in/out
): DWORD; stdcall;
  external 'DHCPSAPI.dll' name 'DhcpGetClientOptions';

result := DllCall("DHCPSAPI\DhcpGetClientOptions"
    , "WStr", ServerIpAddress   ; LPCWSTR optional
    , "UInt", ClientIpAddress   ; DWORD
    , "UInt", ClientSubnetMask   ; DWORD
    , "Ptr", ClientOptions   ; DHCP_OPTION_LIST** in/out
    , "UInt")   ; return: DWORD

●DhcpGetClientOptions(ServerIpAddress, ClientIpAddress, ClientSubnetMask, ClientOptions) = DLL("DHCPSAPI.dll", "dword DhcpGetClientOptions(char*, dword, dword, void*)")
# 呼び出し: DhcpGetClientOptions(ServerIpAddress, ClientIpAddress, ClientSubnetMask, ClientOptions)
# ServerIpAddress : LPCWSTR optional -> "char*"
# ClientIpAddress : DWORD -> "dword"
# ClientSubnetMask : DWORD -> "dword"
# ClientOptions : DHCP_OPTION_LIST** 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)。