CoInitialize

// OLE32.dll
#include <windows.h>

HRESULT CoInitialize(
    void* pvReserved   // optional
);

<DllImport("OLE32.dll", ExactSpelling:=True)>
Public Shared Function CoInitialize(
    pvReserved As IntPtr   ' void* optional
) As Integer
End Function

' pvReserved : void* optional
Declare PtrSafe Function CoInitialize Lib "ole32" ( _
    ByVal pvReserved 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

CoInitialize = ctypes.windll.ole32.CoInitialize
CoInitialize.restype = ctypes.c_int
CoInitialize.argtypes = [
    ctypes.POINTER(None),  # pvReserved : void* optional
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('OLE32.dll')
CoInitialize = Fiddle::Function.new(
  lib['CoInitialize'],
  [
    Fiddle::TYPE_VOIDP,  # pvReserved : void* optional
  ],
  Fiddle::TYPE_INT)

#[link(name = "ole32")]
extern "system" {
    fn CoInitialize(
        pvReserved: *mut ()  // void* optional
    ) -> i32;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("OLE32.dll")]
public static extern int CoInitialize(IntPtr pvReserved);
"@
$api = Add-Type -MemberDefinition $sig -Name 'OLE32_CoInitialize' -Namespace Win32 -PassThru
# $api::CoInitialize(pvReserved)

#uselib "OLE32.dll"
#func global CoInitialize "CoInitialize" sptr
; CoInitialize pvReserved   ; 戻り値は stat
; pvReserved : void* optional -> "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 "OLE32.dll"
#cfunc global CoInitialize "CoInitialize" sptr
; res = CoInitialize(pvReserved)
; pvReserved : void* optional -> "sptr"

; HRESULT CoInitialize(void* pvReserved)
#uselib "OLE32.dll"
#cfunc global CoInitialize "CoInitialize" intptr
; res = CoInitialize(pvReserved)
; pvReserved : void* optional -> "intptr"

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

var (
	ole32 = windows.NewLazySystemDLL("OLE32.dll")
	procCoInitialize = ole32.NewProc("CoInitialize")
)

// pvReserved (void* optional)
r1, _, err := procCoInitialize.Call(
	uintptr(pvReserved),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // HRESULT

function CoInitialize(
  pvReserved: Pointer   // void* optional
): Integer; stdcall;
  external 'OLE32.dll' name 'CoInitialize';

result := DllCall("OLE32\CoInitialize"
    , "Ptr", pvReserved   ; void* optional
    , "Int")   ; return: HRESULT

●CoInitialize(pvReserved) = DLL("OLE32.dll", "int CoInitialize(void*)")
# 呼び出し: CoInitialize(pvReserved)
# pvReserved : void* optional -> "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)。