RegDeleteKeyValueW

// ADVAPI32.dll  (Unicode / -W)
#include <windows.h>

WIN32_ERROR RegDeleteKeyValueW(
    HKEY hKey,
    LPCWSTR lpSubKey,   // optional
    LPCWSTR lpValueName   // optional
);

<DllImport("ADVAPI32.dll", CharSet:=CharSet.Unicode, ExactSpelling:=True)>
Public Shared Function RegDeleteKeyValueW(
    hKey As IntPtr,   ' HKEY
    <MarshalAs(UnmanagedType.LPWStr)> lpSubKey As String,   ' LPCWSTR optional
    <MarshalAs(UnmanagedType.LPWStr)> lpValueName As String   ' LPCWSTR optional
) As UInteger
End Function

' hKey : HKEY
' lpSubKey : LPCWSTR optional
' lpValueName : LPCWSTR optional
Declare PtrSafe Function RegDeleteKeyValueW Lib "advapi32" ( _
    ByVal hKey As LongPtr, _
    ByVal lpSubKey As LongPtr, _
    ByVal lpValueName As LongPtr) As Long
' 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

RegDeleteKeyValueW = ctypes.windll.advapi32.RegDeleteKeyValueW
RegDeleteKeyValueW.restype = wintypes.DWORD
RegDeleteKeyValueW.argtypes = [
    wintypes.HANDLE,  # hKey : HKEY
    wintypes.LPCWSTR,  # lpSubKey : LPCWSTR optional
    wintypes.LPCWSTR,  # lpValueName : LPCWSTR optional
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('ADVAPI32.dll')
RegDeleteKeyValueW = Fiddle::Function.new(
  lib['RegDeleteKeyValueW'],
  [
    Fiddle::TYPE_VOIDP,  # hKey : HKEY
    Fiddle::TYPE_VOIDP,  # lpSubKey : LPCWSTR optional
    Fiddle::TYPE_VOIDP,  # lpValueName : LPCWSTR optional
  ],
  -Fiddle::TYPE_INT)
# Wide strings: pass str.encode("UTF-16LE") + "\x00\x00"

#[link(name = "advapi32")]
extern "system" {
    fn RegDeleteKeyValueW(
        hKey: *mut core::ffi::c_void,  // HKEY
        lpSubKey: *const u16,  // LPCWSTR optional
        lpValueName: *const u16  // LPCWSTR optional
    ) -> u32;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("ADVAPI32.dll", CharSet = CharSet.Unicode)]
public static extern uint RegDeleteKeyValueW(IntPtr hKey, [MarshalAs(UnmanagedType.LPWStr)] string lpSubKey, [MarshalAs(UnmanagedType.LPWStr)] string lpValueName);
"@
$api = Add-Type -MemberDefinition $sig -Name 'ADVAPI32_RegDeleteKeyValueW' -Namespace Win32 -PassThru
# $api::RegDeleteKeyValueW(hKey, lpSubKey, lpValueName)

#uselib "ADVAPI32.dll"
#func global RegDeleteKeyValueW "RegDeleteKeyValueW" wptr, wptr, wptr
; RegDeleteKeyValueW hKey, lpSubKey, lpValueName   ; 戻り値は stat
; hKey : HKEY -> "wptr"
; lpSubKey : LPCWSTR optional -> "wptr"
; lpValueName : LPCWSTR optional -> "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 "ADVAPI32.dll"
#cfunc global RegDeleteKeyValueW "RegDeleteKeyValueW" sptr, wstr, wstr
; res = RegDeleteKeyValueW(hKey, lpSubKey, lpValueName)
; hKey : HKEY -> "sptr"
; lpSubKey : LPCWSTR optional -> "wstr"
; lpValueName : LPCWSTR optional -> "wstr"

; WIN32_ERROR RegDeleteKeyValueW(HKEY hKey, LPCWSTR lpSubKey, LPCWSTR lpValueName)
#uselib "ADVAPI32.dll"
#cfunc global RegDeleteKeyValueW "RegDeleteKeyValueW" intptr, wstr, wstr
; res = RegDeleteKeyValueW(hKey, lpSubKey, lpValueName)
; hKey : HKEY -> "intptr"
; lpSubKey : LPCWSTR optional -> "wstr"
; lpValueName : LPCWSTR optional -> "wstr"

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

var (
	advapi32 = windows.NewLazySystemDLL("ADVAPI32.dll")
	procRegDeleteKeyValueW = advapi32.NewProc("RegDeleteKeyValueW")
)

// hKey (HKEY), lpSubKey (LPCWSTR optional), lpValueName (LPCWSTR optional)
r1, _, err := procRegDeleteKeyValueW.Call(
	uintptr(hKey),
	uintptr(unsafe.Pointer(windows.StringToUTF16Ptr(lpSubKey))),
	uintptr(unsafe.Pointer(windows.StringToUTF16Ptr(lpValueName))),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // WIN32_ERROR

function RegDeleteKeyValueW(
  hKey: THandle;   // HKEY
  lpSubKey: PWideChar;   // LPCWSTR optional
  lpValueName: PWideChar   // LPCWSTR optional
): DWORD; stdcall;
  external 'ADVAPI32.dll' name 'RegDeleteKeyValueW';

result := DllCall("ADVAPI32\RegDeleteKeyValueW"
    , "Ptr", hKey   ; HKEY
    , "WStr", lpSubKey   ; LPCWSTR optional
    , "WStr", lpValueName   ; LPCWSTR optional
    , "UInt")   ; return: WIN32_ERROR

●RegDeleteKeyValueW(hKey, lpSubKey, lpValueName) = DLL("ADVAPI32.dll", "dword RegDeleteKeyValueW(void*, char*, char*)")
# 呼び出し: RegDeleteKeyValueW(hKey, lpSubKey, lpValueName)
# hKey : HKEY -> "void*"
# lpSubKey : LPCWSTR optional -> "char*"
# lpValueName : LPCWSTR optional -> "char*"
# 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。

const std = @import("std");

extern "advapi32" fn RegDeleteKeyValueW(
    hKey: ?*anyopaque, // HKEY
    lpSubKey: [*c]const u16, // LPCWSTR optional
    lpValueName: [*c]const u16 // LPCWSTR optional
) callconv(std.os.windows.WINAPI) u32;
// Unicode(-W): UTF-16LE のヌル終端バッファ([*c]const u16)を渡す。

proc RegDeleteKeyValueW(
    hKey: pointer,  # HKEY
    lpSubKey: WideCString,  # LPCWSTR optional
    lpValueName: WideCString  # LPCWSTR optional
): uint32 {.importc: "RegDeleteKeyValueW", stdcall, dynlib: "ADVAPI32.dll".}
# Unicode(-W): WideCString は newWideCString("...") で生成。

pragma(lib, "advapi32");
extern(Windows)
uint RegDeleteKeyValueW(
    void* hKey,   // HKEY
    const(wchar)* lpSubKey,   // LPCWSTR optional
    const(wchar)* lpValueName   // LPCWSTR optional
);

ccall((:RegDeleteKeyValueW, "ADVAPI32.dll"), stdcall, UInt32,
      (Ptr{Cvoid}, Cwstring, Cwstring),
      hKey, lpSubKey, lpValueName)
# hKey : HKEY -> Ptr{Cvoid}
# lpSubKey : LPCWSTR optional -> Cwstring
# lpValueName : LPCWSTR optional -> Cwstring
# stdcall は 32bit のみ意味を持つ(x64 では無視)。
# Unicode(-W): Cwstring には transcode(UInt16, "...") 等で UTF-16 を渡す。

local ffi = require("ffi")
ffi.cdef[[
uint32_t RegDeleteKeyValueW(
    void* hKey,
    const uint16_t* lpSubKey,
    const uint16_t* lpValueName);
]]
local advapi32 = ffi.load("advapi32")
-- advapi32.RegDeleteKeyValueW(hKey, lpSubKey, lpValueName)
-- hKey : HKEY
-- lpSubKey : LPCWSTR optional
-- lpValueName : LPCWSTR optional
-- 構造体/GUIDへのポインタは cdef が通るよう void* で表記(実型は各引数コメント参照)。値渡し構造体・enum は対応する typedef を cdef に追加すること。
-- Unicode(-W): uint16_t* には UTF-16LE のバッファ(ffi.new("uint16_t[?]", ...))を渡す。

const koffi = require('koffi');
const lib = koffi.load('ADVAPI32.dll');
const RegDeleteKeyValueW = lib.func('__stdcall', 'RegDeleteKeyValueW', 'uint32_t', ['void *', 'str16', 'str16']);
// RegDeleteKeyValueW(hKey, lpSubKey, lpValueName)
// hKey : HKEY -> 'void *'
// lpSubKey : LPCWSTR optional -> 'str16'
// lpValueName : LPCWSTR optional -> 'str16'
// 出力ポインタは koffi.out(...) で包む。構造体は koffi.struct で定義。

const lib = Deno.dlopen("ADVAPI32.dll", {
  RegDeleteKeyValueW: { parameters: ["pointer", "buffer", "buffer"], result: "u32" },
});
// lib.symbols.RegDeleteKeyValueW(hKey, lpSubKey, lpValueName)
// hKey : HKEY -> "pointer"
// lpSubKey : LPCWSTR optional -> "buffer"
// lpValueName : LPCWSTR optional -> "buffer"
// 文字列は "buffer"。Unicode(-W) は new TextEncoder() ではなく UTF-16LE のバイト列(末尾に \x00\x00)を Uint8Array で渡す。
// 値渡し構造体は { struct: [ ...field types... ] } を使用。

<?php
$ffi = FFI::cdef(<<<C
uint32_t RegDeleteKeyValueW(
    void* hKey,
    const uint16_t* lpSubKey,
    const uint16_t* lpValueName);
C, "ADVAPI32.dll");
// $ffi->RegDeleteKeyValueW(hKey, lpSubKey, lpValueName);
// hKey : HKEY
// lpSubKey : LPCWSTR optional
// lpValueName : LPCWSTR optional
// 構造体/GUIDへのポインタは cdef が通るよう void* で表記(実型は各引数コメント参照)。値渡し構造体・enum は対応する typedef を cdef に追加すること。
// WINAPI(stdcall): x64 では呼出規約が統一されるため問題なし。x86 では __stdcall 対応のラッパが必要な場合あり。

import com.sun.jna.*;
import com.sun.jna.ptr.*;
import com.sun.jna.win32.StdCallLibrary;
import com.sun.jna.win32.W32APIOptions;

public interface Advapi32 extends StdCallLibrary {
    Advapi32 INSTANCE = Native.load("advapi32", Advapi32.class, W32APIOptions.UNICODE_OPTIONS);
    int RegDeleteKeyValueW(
        Pointer hKey,   // HKEY
        WString lpSubKey,   // LPCWSTR optional
        WString lpValueName   // LPCWSTR optional
    );
}
// Unicode(-W): WString(入力)/char[](出力)で UTF-16 をマーシャリング。

@[Link("advapi32")]
lib LibADVAPI32
  fun RegDeleteKeyValueW = RegDeleteKeyValueW(
    hKey : Void*,   # HKEY
    lpSubKey : UInt16*,   # LPCWSTR optional
    lpValueName : UInt16*   # LPCWSTR optional
  ) : UInt32
end
# 構造体/GUID/enum は lib 内に対応する型定義が必要。
# 呼出規約: x64 は規約統一のため OK。x86(32bit)は WINAPI=stdcall だが Crystal の fun に stdcall 付与構文がなく非対応。

import 'dart:ffi';
import 'package:ffi/ffi.dart';

typedef RegDeleteKeyValueWNative = Uint32 Function(Pointer<Void>, Pointer<Utf16>, Pointer<Utf16>);
typedef RegDeleteKeyValueWDart = int Function(Pointer<Void>, Pointer<Utf16>, Pointer<Utf16>);
final RegDeleteKeyValueW = DynamicLibrary.open('ADVAPI32.dll')
    .lookupFunction<RegDeleteKeyValueWNative, RegDeleteKeyValueWDart>('RegDeleteKeyValueW');
// hKey : HKEY -> Pointer<Void>
// lpSubKey : LPCWSTR optional -> Pointer<Utf16>
// lpValueName : LPCWSTR optional -> Pointer<Utf16>
// 文字列は package:ffi の "...".toNativeUtf16()/toNativeUtf8() で変換。

{$mode objfpc}{$H+}
function RegDeleteKeyValueW(
  hKey: THandle;   // HKEY
  lpSubKey: PWideChar;   // LPCWSTR optional
  lpValueName: PWideChar   // LPCWSTR optional
): DWORD; stdcall;
  external 'ADVAPI32.dll' name 'RegDeleteKeyValueW';

import Foreign
import Foreign.C.Types
import Foreign.C.String

foreign import stdcall safe "RegDeleteKeyValueW"
  c_RegDeleteKeyValueW :: Ptr () -> CWString -> CWString -> IO Word32
-- hKey : HKEY -> Ptr ()
-- lpSubKey : LPCWSTR optional -> CWString
-- lpValueName : LPCWSTR optional -> CWString
-- 要 GHC(Windows)。stdcall は x64 では ccall として扱われる。ブロックする API は safe 呼び出し推奨。

open Ctypes
open Foreign

let regdeletekeyvaluew =
  foreign "RegDeleteKeyValueW"
    ((ptr void) @-> (ptr uint16_t) @-> (ptr uint16_t) @-> returning uint32_t)
(* hKey : HKEY -> (ptr void) *)
(* lpSubKey : LPCWSTR optional -> (ptr uint16_t) *)
(* lpValueName : LPCWSTR optional -> (ptr uint16_t) *)
(* foreign は cdecl 前提。x64 Windows では WINAPI と一致。構造体は ctypes structure を定義のこと。 *)

(cffi:define-foreign-library advapi32 (t "ADVAPI32.dll"))
(cffi:use-foreign-library advapi32)

(cffi:defcfun ("RegDeleteKeyValueW" reg-delete-key-value-w :convention :stdcall) :uint32
  (h-key :pointer)   ; HKEY
  (lp-sub-key (:string :encoding :utf-16le))   ; LPCWSTR optional
  (lp-value-name (:string :encoding :utf-16le)))   ; LPCWSTR optional
; isize/usize(INT_PTR/SIZE_T)は x64 前提で :int64/:uint64。x86 では :int32/:uint32。

use Win32::API;
my $RegDeleteKeyValueW = Win32::API::More->new('ADVAPI32',
    'DWORD RegDeleteKeyValueW(HANDLE hKey, LPCWSTR lpSubKey, LPCWSTR lpValueName)');
# my $ret = $RegDeleteKeyValueW->Call($hKey, $lpSubKey, $lpValueName);
# hKey : HKEY -> HANDLE
# lpSubKey : LPCWSTR optional -> LPCWSTR
# lpValueName : LPCWSTR optional -> LPCWSTR
# 値渡し構造体は pack() した文字列、または Win32::API::Struct を使用。
# Unicode(-W): LPCWSTR/LPWSTR は Win32::API が UTF-16 変換を行う。