RealChildWindowFromPoint

// USER32.dll
#include <windows.h>

HWND RealChildWindowFromPoint(
    HWND hwndParent,
    POINT ptParentClientCoords
);

<DllImport("USER32.dll", ExactSpelling:=True)>
Public Shared Function RealChildWindowFromPoint(
    hwndParent As IntPtr,   ' HWND
    ptParentClientCoords As POINT   ' POINT
) As IntPtr
End Function

' hwndParent : HWND
' ptParentClientCoords : POINT
Declare PtrSafe Function RealChildWindowFromPoint Lib "user32" ( _
    ByVal hwndParent As LongPtr, _
    ByVal ptParentClientCoords As LongPtr) As LongPtr
' VBA7前提(PtrSafe)。32bit Office では LongPtr→Long。Integer=16bit / Long=32bit / LongLong=64bit。

import ctypes
from ctypes import wintypes

RealChildWindowFromPoint = ctypes.windll.user32.RealChildWindowFromPoint
RealChildWindowFromPoint.restype = ctypes.c_void_p
RealChildWindowFromPoint.argtypes = [
    wintypes.HANDLE,  # hwndParent : HWND
    POINT,  # ptParentClientCoords : POINT
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('USER32.dll')
RealChildWindowFromPoint = Fiddle::Function.new(
  lib['RealChildWindowFromPoint'],
  [
    Fiddle::TYPE_VOIDP,  # hwndParent : HWND
    Fiddle::TYPE_VOIDP,  # ptParentClientCoords : POINT
  ],
  Fiddle::TYPE_VOIDP)

#[link(name = "user32")]
extern "system" {
    fn RealChildWindowFromPoint(
        hwndParent: *mut core::ffi::c_void,  // HWND
        ptParentClientCoords: POINT  // POINT
    ) -> *mut core::ffi::c_void;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("USER32.dll")]
public static extern IntPtr RealChildWindowFromPoint(IntPtr hwndParent, POINT ptParentClientCoords);
"@
$api = Add-Type -MemberDefinition $sig -Name 'USER32_RealChildWindowFromPoint' -Namespace Win32 -PassThru
# $api::RealChildWindowFromPoint(hwndParent, ptParentClientCoords)

#uselib "USER32.dll"
#func global RealChildWindowFromPoint "RealChildWindowFromPoint" sptr, sptr
; RealChildWindowFromPoint hwndParent, ptParentClientCoords   ; 戻り値は stat
; hwndParent : HWND -> "sptr"
; ptParentClientCoords : POINT -> "sptr"
; ※値渡し構造体は直接渡せません。intにパック、または var で構造体変数を渡してください。
; ※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 "USER32.dll"
#cfunc global RealChildWindowFromPoint "RealChildWindowFromPoint" sptr, int
; res = RealChildWindowFromPoint(hwndParent, ptParentClientCoords)
; hwndParent : HWND -> "sptr"
; ptParentClientCoords : POINT -> "int"
; ※値渡し構造体は直接渡せません。intにパック、または var で構造体変数を渡してください。

; HWND RealChildWindowFromPoint(HWND hwndParent, POINT ptParentClientCoords)
#uselib "USER32.dll"
#cfunc global RealChildWindowFromPoint "RealChildWindowFromPoint" intptr, int
; res = RealChildWindowFromPoint(hwndParent, ptParentClientCoords)
; hwndParent : HWND -> "intptr"
; ptParentClientCoords : POINT -> "int"
; ※値渡し構造体は直接渡せません。intにパック、または var で構造体変数を渡してください。

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

var (
	user32 = windows.NewLazySystemDLL("USER32.dll")
	procRealChildWindowFromPoint = user32.NewProc("RealChildWindowFromPoint")
)

// hwndParent (HWND), ptParentClientCoords (POINT)
r1, _, err := procRealChildWindowFromPoint.Call(
	uintptr(hwndParent),
	uintptr(ptParentClientCoords),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // HWND

function RealChildWindowFromPoint(
  hwndParent: THandle;   // HWND
  ptParentClientCoords: POINT   // POINT
): THandle; stdcall;
  external 'USER32.dll' name 'RealChildWindowFromPoint';

result := DllCall("USER32\RealChildWindowFromPoint"
    , "Ptr", hwndParent   ; HWND
    , "Ptr", ptParentClientCoords   ; POINT
    , "Ptr")   ; return: HWND

●RealChildWindowFromPoint(hwndParent, ptParentClientCoords) = DLL("USER32.dll", "void* RealChildWindowFromPoint(void*, void*)")
# 呼び出し: RealChildWindowFromPoint(hwndParent, ptParentClientCoords)
# hwndParent : HWND -> "void*"
# ptParentClientCoords : POINT -> "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)。