OFNOTIFYW

using System;
using System.Runtime.InteropServices;

[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
public struct NMHDR
{
    public IntPtr hwndFrom;
    public UIntPtr idFrom;
    public uint code;
}

[StructLayout(LayoutKind.Sequential, Pack = 1, CharSet = CharSet.Unicode)]
public struct OFNOTIFYW
{
    public NMHDR hdr;
    public IntPtr lpOFN;
    public IntPtr pszFile;
}

Imports System.Runtime.InteropServices

<StructLayout(LayoutKind.Sequential, CharSet:=CharSet.Unicode)>
Public Structure NMHDR
    Public hwndFrom As IntPtr
    Public idFrom As UIntPtr
    Public code As UInteger
End Structure

<StructLayout(LayoutKind.Sequential, Pack:=1, CharSet:=CharSet.Unicode)>
Public Structure OFNOTIFYW
    Public hdr As NMHDR
    Public lpOFN As IntPtr
    Public pszFile As IntPtr
End Structure

import ctypes
from ctypes import wintypes

class NMHDR(ctypes.Structure):
    _fields_ = [
        ("hwndFrom", ctypes.c_void_p),
        ("idFrom", ctypes.c_size_t),
        ("code", wintypes.DWORD),
    ]

class OFNOTIFYW(ctypes.Structure):
    _pack_ = 1
    _fields_ = [
        ("hdr", NMHDR),
        ("lpOFN", ctypes.c_void_p),
        ("pszFile", ctypes.c_void_p),
    ]

#[repr(C)]
pub struct NMHDR {
    pub hwndFrom: *mut core::ffi::c_void,
    pub idFrom: usize,
    pub code: u32,
}

#[repr(C, packed(1))]
pub struct OFNOTIFYW {
    pub hdr: NMHDR,
    pub lpOFN: *mut core::ffi::c_void,
    pub pszFile: *mut core::ffi::c_void,
}

import "golang.org/x/sys/windows"

type NMHDR struct {
	hwndFrom uintptr
	idFrom uintptr
	code uint32
}

type OFNOTIFYW struct {
	hdr NMHDR
	lpOFN uintptr
	pszFile uintptr
}

type
  NMHDR = record
    hwndFrom: Pointer;
    idFrom: NativeUInt;
    code: DWORD;
  end;

  OFNOTIFYW = packed record
    hdr: NMHDR;
    lpOFN: Pointer;
    pszFile: Pointer;
  end;

const NMHDR = extern struct {
    hwndFrom: ?*anyopaque,
    idFrom: usize,
    code: u32,
};

const OFNOTIFYW = extern struct {
    hdr: NMHDR,
    lpOFN: ?*anyopaque,
    pszFile: ?*anyopaque,
};

type
  NMHDR {.bycopy.} = object
    hwndFrom: pointer
    idFrom: uint
    code: uint32

  OFNOTIFYW {.packed.} = object
    hdr: NMHDR
    lpOFN: pointer
    pszFile: pointer

struct NMHDR
{
    void* hwndFrom;
    size_t idFrom;
    uint code;
}

align(1)
struct OFNOTIFYW
{
    NMHDR hdr;
    void* lpOFN;
    void* pszFile;
}