SHOpenRegStreamW

// SHLWAPI.dll  (Unicode / -W)
#include <windows.h>

IStream* SHOpenRegStreamW(
    HKEY hkey,
    LPCWSTR pszSubkey,   // optional
    LPCWSTR pszValue,   // optional
    DWORD grfMode
);

<DllImport("SHLWAPI.dll", CharSet:=CharSet.Unicode, ExactSpelling:=True)>
Public Shared Function SHOpenRegStreamW(
    hkey As IntPtr,   ' HKEY
    <MarshalAs(UnmanagedType.LPWStr)> pszSubkey As String,   ' LPCWSTR optional
    <MarshalAs(UnmanagedType.LPWStr)> pszValue As String,   ' LPCWSTR optional
    grfMode As UInteger   ' DWORD
) As IntPtr
End Function

' hkey : HKEY
' pszSubkey : LPCWSTR optional
' pszValue : LPCWSTR optional
' grfMode : DWORD
Declare PtrSafe Function SHOpenRegStreamW Lib "shlwapi" ( _
    ByVal hkey As LongPtr, _
    ByVal pszSubkey As LongPtr, _
    ByVal pszValue As LongPtr, _
    ByVal grfMode As Long) As LongPtr
' Unicode(W): 文字列は ByVal As LongPtr とし StrPtr(unicodeStr) を渡す
' VBA7前提(PtrSafe)。32bit Office では LongPtr→Long。Integer=16bit / Long=32bit / LongLong=64bit。

import ctypes
from ctypes import wintypes

SHOpenRegStreamW = ctypes.windll.shlwapi.SHOpenRegStreamW
SHOpenRegStreamW.restype = ctypes.c_void_p
SHOpenRegStreamW.argtypes = [
    wintypes.HANDLE,  # hkey : HKEY
    wintypes.LPCWSTR,  # pszSubkey : LPCWSTR optional
    wintypes.LPCWSTR,  # pszValue : LPCWSTR optional
    wintypes.DWORD,  # grfMode : DWORD
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('SHLWAPI.dll')
SHOpenRegStreamW = Fiddle::Function.new(
  lib['SHOpenRegStreamW'],
  [
    Fiddle::TYPE_VOIDP,  # hkey : HKEY
    Fiddle::TYPE_VOIDP,  # pszSubkey : LPCWSTR optional
    Fiddle::TYPE_VOIDP,  # pszValue : LPCWSTR optional
    -Fiddle::TYPE_INT,  # grfMode : DWORD
  ],
  Fiddle::TYPE_VOIDP)
# Wide strings: pass str.encode("UTF-16LE") + "\x00\x00"

#[link(name = "shlwapi")]
extern "system" {
    fn SHOpenRegStreamW(
        hkey: *mut core::ffi::c_void,  // HKEY
        pszSubkey: *const u16,  // LPCWSTR optional
        pszValue: *const u16,  // LPCWSTR optional
        grfMode: u32  // DWORD
    ) -> *mut core::ffi::c_void;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("SHLWAPI.dll", CharSet = CharSet.Unicode)]
public static extern IntPtr SHOpenRegStreamW(IntPtr hkey, [MarshalAs(UnmanagedType.LPWStr)] string pszSubkey, [MarshalAs(UnmanagedType.LPWStr)] string pszValue, uint grfMode);
"@
$api = Add-Type -MemberDefinition $sig -Name 'SHLWAPI_SHOpenRegStreamW' -Namespace Win32 -PassThru
# $api::SHOpenRegStreamW(hkey, pszSubkey, pszValue, grfMode)

#uselib "SHLWAPI.dll"
#func global SHOpenRegStreamW "SHOpenRegStreamW" wptr, wptr, wptr, wptr
; SHOpenRegStreamW hkey, pszSubkey, pszValue, grfMode   ; 戻り値は stat
; hkey : HKEY -> "wptr"
; pszSubkey : LPCWSTR optional -> "wptr"
; pszValue : LPCWSTR optional -> "wptr"
; grfMode : DWORD -> "wptr"
; ※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 "SHLWAPI.dll"
#cfunc global SHOpenRegStreamW "SHOpenRegStreamW" sptr, wstr, wstr, int
; res = SHOpenRegStreamW(hkey, pszSubkey, pszValue, grfMode)
; hkey : HKEY -> "sptr"
; pszSubkey : LPCWSTR optional -> "wstr"
; pszValue : LPCWSTR optional -> "wstr"
; grfMode : DWORD -> "int"

; IStream* SHOpenRegStreamW(HKEY hkey, LPCWSTR pszSubkey, LPCWSTR pszValue, DWORD grfMode)
#uselib "SHLWAPI.dll"
#cfunc global SHOpenRegStreamW "SHOpenRegStreamW" intptr, wstr, wstr, int
; res = SHOpenRegStreamW(hkey, pszSubkey, pszValue, grfMode)
; hkey : HKEY -> "intptr"
; pszSubkey : LPCWSTR optional -> "wstr"
; pszValue : LPCWSTR optional -> "wstr"
; grfMode : DWORD -> "int"

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

var (
	shlwapi = windows.NewLazySystemDLL("SHLWAPI.dll")
	procSHOpenRegStreamW = shlwapi.NewProc("SHOpenRegStreamW")
)

// hkey (HKEY), pszSubkey (LPCWSTR optional), pszValue (LPCWSTR optional), grfMode (DWORD)
r1, _, err := procSHOpenRegStreamW.Call(
	uintptr(hkey),
	uintptr(unsafe.Pointer(windows.StringToUTF16Ptr(pszSubkey))),
	uintptr(unsafe.Pointer(windows.StringToUTF16Ptr(pszValue))),
	uintptr(grfMode),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // IStream*

function SHOpenRegStreamW(
  hkey: THandle;   // HKEY
  pszSubkey: PWideChar;   // LPCWSTR optional
  pszValue: PWideChar;   // LPCWSTR optional
  grfMode: DWORD   // DWORD
): Pointer; stdcall;
  external 'SHLWAPI.dll' name 'SHOpenRegStreamW';

result := DllCall("SHLWAPI\SHOpenRegStreamW"
    , "Ptr", hkey   ; HKEY
    , "WStr", pszSubkey   ; LPCWSTR optional
    , "WStr", pszValue   ; LPCWSTR optional
    , "UInt", grfMode   ; DWORD
    , "Ptr")   ; return: IStream*

●SHOpenRegStreamW(hkey, pszSubkey, pszValue, grfMode) = DLL("SHLWAPI.dll", "void* SHOpenRegStreamW(void*, char*, char*, dword)")
# 呼び出し: SHOpenRegStreamW(hkey, pszSubkey, pszValue, grfMode)
# hkey : HKEY -> "void*"
# pszSubkey : LPCWSTR optional -> "char*"
# pszValue : LPCWSTR optional -> "char*"
# grfMode : DWORD -> "dword"
# 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)。
# ※-W(Unicode)関数。なでしこ1はANSIのため -A 版の利用を推奨。