DispGetParam

// OLEAUT32.dll
#include <windows.h>

HRESULT DispGetParam(
    DISPPARAMS* pdispparams,
    DWORD position,
    VARENUM vtTarg,
    VARIANT* pvarResult,
    DWORD* puArgErr   // optional
);

<DllImport("OLEAUT32.dll", ExactSpelling:=True)>
Public Shared Function DispGetParam(
    pdispparams As IntPtr,   ' DISPPARAMS*
    position As UInteger,   ' DWORD
    vtTarg As UShort,   ' VARENUM
    pvarResult As IntPtr,   ' VARIANT* out
    puArgErr As IntPtr   ' DWORD* optional, out
) As Integer
End Function

' pdispparams : DISPPARAMS*
' position : DWORD
' vtTarg : VARENUM
' pvarResult : VARIANT* out
' puArgErr : DWORD* optional, out
Declare PtrSafe Function DispGetParam Lib "oleaut32" ( _
    ByVal pdispparams As LongPtr, _
    ByVal position As Long, _
    ByVal vtTarg As Integer, _
    ByVal pvarResult As LongPtr, _
    ByVal puArgErr 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

DispGetParam = ctypes.windll.oleaut32.DispGetParam
DispGetParam.restype = ctypes.c_int
DispGetParam.argtypes = [
    ctypes.c_void_p,  # pdispparams : DISPPARAMS*
    wintypes.DWORD,  # position : DWORD
    ctypes.c_ushort,  # vtTarg : VARENUM
    ctypes.c_void_p,  # pvarResult : VARIANT* out
    ctypes.POINTER(wintypes.DWORD),  # puArgErr : DWORD* optional, out
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('OLEAUT32.dll')
DispGetParam = Fiddle::Function.new(
  lib['DispGetParam'],
  [
    Fiddle::TYPE_VOIDP,  # pdispparams : DISPPARAMS*
    -Fiddle::TYPE_INT,  # position : DWORD
    -Fiddle::TYPE_SHORT,  # vtTarg : VARENUM
    Fiddle::TYPE_VOIDP,  # pvarResult : VARIANT* out
    Fiddle::TYPE_VOIDP,  # puArgErr : DWORD* optional, out
  ],
  Fiddle::TYPE_INT)

#[link(name = "oleaut32")]
extern "system" {
    fn DispGetParam(
        pdispparams: *mut DISPPARAMS,  // DISPPARAMS*
        position: u32,  // DWORD
        vtTarg: u16,  // VARENUM
        pvarResult: *mut VARIANT,  // VARIANT* out
        puArgErr: *mut u32  // DWORD* optional, out
    ) -> i32;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("OLEAUT32.dll")]
public static extern int DispGetParam(IntPtr pdispparams, uint position, ushort vtTarg, IntPtr pvarResult, IntPtr puArgErr);
"@
$api = Add-Type -MemberDefinition $sig -Name 'OLEAUT32_DispGetParam' -Namespace Win32 -PassThru
# $api::DispGetParam(pdispparams, position, vtTarg, pvarResult, puArgErr)

#uselib "OLEAUT32.dll"
#func global DispGetParam "DispGetParam" sptr, sptr, sptr, sptr, sptr
; DispGetParam varptr(pdispparams), position, vtTarg, varptr(pvarResult), varptr(puArgErr)   ; 戻り値は stat
; pdispparams : DISPPARAMS* -> "sptr"
; position : DWORD -> "sptr"
; vtTarg : VARENUM -> "sptr"
; pvarResult : VARIANT* out -> "sptr"
; puArgErr : DWORD* optional, 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 "OLEAUT32.dll"
#cfunc global DispGetParam "DispGetParam" var, int, int, var, var
; res = DispGetParam(pdispparams, position, vtTarg, pvarResult, puArgErr)
; pdispparams : DISPPARAMS* -> "var"
; position : DWORD -> "int"
; vtTarg : VARENUM -> "int"
; pvarResult : VARIANT* out -> "var"
; puArgErr : DWORD* optional, 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。

; HRESULT DispGetParam(DISPPARAMS* pdispparams, DWORD position, VARENUM vtTarg, VARIANT* pvarResult, DWORD* puArgErr)
#uselib "OLEAUT32.dll"
#cfunc global DispGetParam "DispGetParam" var, int, int, var, var
; res = DispGetParam(pdispparams, position, vtTarg, pvarResult, puArgErr)
; pdispparams : DISPPARAMS* -> "var"
; position : DWORD -> "int"
; vtTarg : VARENUM -> "int"
; pvarResult : VARIANT* out -> "var"
; puArgErr : DWORD* optional, 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 (
	oleaut32 = windows.NewLazySystemDLL("OLEAUT32.dll")
	procDispGetParam = oleaut32.NewProc("DispGetParam")
)

// pdispparams (DISPPARAMS*), position (DWORD), vtTarg (VARENUM), pvarResult (VARIANT* out), puArgErr (DWORD* optional, out)
r1, _, err := procDispGetParam.Call(
	uintptr(pdispparams),
	uintptr(position),
	uintptr(vtTarg),
	uintptr(pvarResult),
	uintptr(puArgErr),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // HRESULT

function DispGetParam(
  pdispparams: Pointer;   // DISPPARAMS*
  position: DWORD;   // DWORD
  vtTarg: Word;   // VARENUM
  pvarResult: Pointer;   // VARIANT* out
  puArgErr: Pointer   // DWORD* optional, out
): Integer; stdcall;
  external 'OLEAUT32.dll' name 'DispGetParam';

result := DllCall("OLEAUT32\DispGetParam"
    , "Ptr", pdispparams   ; DISPPARAMS*
    , "UInt", position   ; DWORD
    , "UShort", vtTarg   ; VARENUM
    , "Ptr", pvarResult   ; VARIANT* out
    , "Ptr", puArgErr   ; DWORD* optional, out
    , "Int")   ; return: HRESULT

●DispGetParam(pdispparams, position, vtTarg, pvarResult, puArgErr) = DLL("OLEAUT32.dll", "int DispGetParam(void*, dword, int, void*, void*)")
# 呼び出し: DispGetParam(pdispparams, position, vtTarg, pvarResult, puArgErr)
# pdispparams : DISPPARAMS* -> "void*"
# position : DWORD -> "dword"
# vtTarg : VARENUM -> "int"
# pvarResult : VARIANT* out -> "void*"
# puArgErr : DWORD* optional, 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)。