SHEmptyRecycleBinW

// SHELL32.dll  (Unicode / -W)
#include <windows.h>

HRESULT SHEmptyRecycleBinW(
    HWND hwnd,   // optional
    LPCWSTR pszRootPath,   // optional
    DWORD dwFlags
);

<DllImport("SHELL32.dll", CharSet:=CharSet.Unicode, ExactSpelling:=True)>
Public Shared Function SHEmptyRecycleBinW(
    hwnd As IntPtr,   ' HWND optional
    <MarshalAs(UnmanagedType.LPWStr)> pszRootPath As String,   ' LPCWSTR optional
    dwFlags As UInteger   ' DWORD
) As Integer
End Function

' hwnd : HWND optional
' pszRootPath : LPCWSTR optional
' dwFlags : DWORD
Declare PtrSafe Function SHEmptyRecycleBinW Lib "shell32" ( _
    ByVal hwnd As LongPtr, _
    ByVal pszRootPath As LongPtr, _
    ByVal dwFlags As Long) 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

SHEmptyRecycleBinW = ctypes.windll.shell32.SHEmptyRecycleBinW
SHEmptyRecycleBinW.restype = ctypes.c_int
SHEmptyRecycleBinW.argtypes = [
    wintypes.HANDLE,  # hwnd : HWND optional
    wintypes.LPCWSTR,  # pszRootPath : LPCWSTR optional
    wintypes.DWORD,  # dwFlags : DWORD
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('SHELL32.dll')
SHEmptyRecycleBinW = Fiddle::Function.new(
  lib['SHEmptyRecycleBinW'],
  [
    Fiddle::TYPE_VOIDP,  # hwnd : HWND optional
    Fiddle::TYPE_VOIDP,  # pszRootPath : LPCWSTR optional
    -Fiddle::TYPE_INT,  # dwFlags : DWORD
  ],
  Fiddle::TYPE_INT)
# Wide strings: pass str.encode("UTF-16LE") + "\x00\x00"

#[link(name = "shell32")]
extern "system" {
    fn SHEmptyRecycleBinW(
        hwnd: *mut core::ffi::c_void,  // HWND optional
        pszRootPath: *const u16,  // LPCWSTR optional
        dwFlags: u32  // DWORD
    ) -> i32;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("SHELL32.dll", CharSet = CharSet.Unicode)]
public static extern int SHEmptyRecycleBinW(IntPtr hwnd, [MarshalAs(UnmanagedType.LPWStr)] string pszRootPath, uint dwFlags);
"@
$api = Add-Type -MemberDefinition $sig -Name 'SHELL32_SHEmptyRecycleBinW' -Namespace Win32 -PassThru
# $api::SHEmptyRecycleBinW(hwnd, pszRootPath, dwFlags)

#uselib "SHELL32.dll"
#func global SHEmptyRecycleBinW "SHEmptyRecycleBinW" wptr, wptr, wptr
; SHEmptyRecycleBinW hwnd, pszRootPath, dwFlags   ; 戻り値は stat
; hwnd : HWND optional -> "wptr"
; pszRootPath : LPCWSTR optional -> "wptr"
; dwFlags : 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 "SHELL32.dll"
#cfunc global SHEmptyRecycleBinW "SHEmptyRecycleBinW" sptr, wstr, int
; res = SHEmptyRecycleBinW(hwnd, pszRootPath, dwFlags)
; hwnd : HWND optional -> "sptr"
; pszRootPath : LPCWSTR optional -> "wstr"
; dwFlags : DWORD -> "int"

; HRESULT SHEmptyRecycleBinW(HWND hwnd, LPCWSTR pszRootPath, DWORD dwFlags)
#uselib "SHELL32.dll"
#cfunc global SHEmptyRecycleBinW "SHEmptyRecycleBinW" intptr, wstr, int
; res = SHEmptyRecycleBinW(hwnd, pszRootPath, dwFlags)
; hwnd : HWND optional -> "intptr"
; pszRootPath : LPCWSTR optional -> "wstr"
; dwFlags : DWORD -> "int"

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

var (
	shell32 = windows.NewLazySystemDLL("SHELL32.dll")
	procSHEmptyRecycleBinW = shell32.NewProc("SHEmptyRecycleBinW")
)

// hwnd (HWND optional), pszRootPath (LPCWSTR optional), dwFlags (DWORD)
r1, _, err := procSHEmptyRecycleBinW.Call(
	uintptr(hwnd),
	uintptr(unsafe.Pointer(windows.StringToUTF16Ptr(pszRootPath))),
	uintptr(dwFlags),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // HRESULT

function SHEmptyRecycleBinW(
  hwnd: THandle;   // HWND optional
  pszRootPath: PWideChar;   // LPCWSTR optional
  dwFlags: DWORD   // DWORD
): Integer; stdcall;
  external 'SHELL32.dll' name 'SHEmptyRecycleBinW';

result := DllCall("SHELL32\SHEmptyRecycleBinW"
    , "Ptr", hwnd   ; HWND optional
    , "WStr", pszRootPath   ; LPCWSTR optional
    , "UInt", dwFlags   ; DWORD
    , "Int")   ; return: HRESULT

●SHEmptyRecycleBinW(hwnd, pszRootPath, dwFlags) = DLL("SHELL32.dll", "int SHEmptyRecycleBinW(void*, char*, dword)")
# 呼び出し: SHEmptyRecycleBinW(hwnd, pszRootPath, dwFlags)
# hwnd : HWND optional -> "void*"
# pszRootPath : LPCWSTR optional -> "char*"
# dwFlags : 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。