VarCat

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

HRESULT VarCat(
    VARIANT* pvarLeft,
    VARIANT* pvarRight,
    VARIANT* pvarResult
);

<DllImport("OLEAUT32.dll", ExactSpelling:=True)>
Public Shared Function VarCat(
    pvarLeft As IntPtr,   ' VARIANT*
    pvarRight As IntPtr,   ' VARIANT*
    pvarResult As IntPtr   ' VARIANT* out
) As Integer
End Function

' pvarLeft : VARIANT*
' pvarRight : VARIANT*
' pvarResult : VARIANT* out
Declare PtrSafe Function VarCat Lib "oleaut32" ( _
    ByVal pvarLeft As LongPtr, _
    ByVal pvarRight As LongPtr, _
    ByVal pvarResult 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

VarCat = ctypes.windll.oleaut32.VarCat
VarCat.restype = ctypes.c_int
VarCat.argtypes = [
    ctypes.c_void_p,  # pvarLeft : VARIANT*
    ctypes.c_void_p,  # pvarRight : VARIANT*
    ctypes.c_void_p,  # pvarResult : VARIANT* out
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('OLEAUT32.dll')
VarCat = Fiddle::Function.new(
  lib['VarCat'],
  [
    Fiddle::TYPE_VOIDP,  # pvarLeft : VARIANT*
    Fiddle::TYPE_VOIDP,  # pvarRight : VARIANT*
    Fiddle::TYPE_VOIDP,  # pvarResult : VARIANT* out
  ],
  Fiddle::TYPE_INT)

#[link(name = "oleaut32")]
extern "system" {
    fn VarCat(
        pvarLeft: *mut VARIANT,  // VARIANT*
        pvarRight: *mut VARIANT,  // VARIANT*
        pvarResult: *mut VARIANT  // VARIANT* out
    ) -> i32;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("OLEAUT32.dll")]
public static extern int VarCat(IntPtr pvarLeft, IntPtr pvarRight, IntPtr pvarResult);
"@
$api = Add-Type -MemberDefinition $sig -Name 'OLEAUT32_VarCat' -Namespace Win32 -PassThru
# $api::VarCat(pvarLeft, pvarRight, pvarResult)

#uselib "OLEAUT32.dll"
#func global VarCat "VarCat" sptr, sptr, sptr
; VarCat varptr(pvarLeft), varptr(pvarRight), varptr(pvarResult)   ; 戻り値は stat
; pvarLeft : VARIANT* -> "sptr"
; pvarRight : VARIANT* -> "sptr"
; pvarResult : VARIANT* 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 VarCat "VarCat" var, var, var
; res = VarCat(pvarLeft, pvarRight, pvarResult)
; pvarLeft : VARIANT* -> "var"
; pvarRight : VARIANT* -> "var"
; pvarResult : VARIANT* 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 VarCat(VARIANT* pvarLeft, VARIANT* pvarRight, VARIANT* pvarResult)
#uselib "OLEAUT32.dll"
#cfunc global VarCat "VarCat" var, var, var
; res = VarCat(pvarLeft, pvarRight, pvarResult)
; pvarLeft : VARIANT* -> "var"
; pvarRight : VARIANT* -> "var"
; pvarResult : VARIANT* 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")
	procVarCat = oleaut32.NewProc("VarCat")
)

// pvarLeft (VARIANT*), pvarRight (VARIANT*), pvarResult (VARIANT* out)
r1, _, err := procVarCat.Call(
	uintptr(pvarLeft),
	uintptr(pvarRight),
	uintptr(pvarResult),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // HRESULT

function VarCat(
  pvarLeft: Pointer;   // VARIANT*
  pvarRight: Pointer;   // VARIANT*
  pvarResult: Pointer   // VARIANT* out
): Integer; stdcall;
  external 'OLEAUT32.dll' name 'VarCat';

result := DllCall("OLEAUT32\VarCat"
    , "Ptr", pvarLeft   ; VARIANT*
    , "Ptr", pvarRight   ; VARIANT*
    , "Ptr", pvarResult   ; VARIANT* out
    , "Int")   ; return: HRESULT

●VarCat(pvarLeft, pvarRight, pvarResult) = DLL("OLEAUT32.dll", "int VarCat(void*, void*, void*)")
# 呼び出し: VarCat(pvarLeft, pvarRight, pvarResult)
# pvarLeft : VARIANT* -> "void*"
# pvarRight : VARIANT* -> "void*"
# pvarResult : VARIANT* 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)。