DdeGetData

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

DWORD DdeGetData(
    HDDEDATA hData,
    BYTE* pDst,   // optional
    DWORD cbMax,
    DWORD cbOff
);

<DllImport("USER32.dll", ExactSpelling:=True)>
Public Shared Function DdeGetData(
    hData As IntPtr,   ' HDDEDATA
    pDst As IntPtr,   ' BYTE* optional, out
    cbMax As UInteger,   ' DWORD
    cbOff As UInteger   ' DWORD
) As UInteger
End Function

' hData : HDDEDATA
' pDst : BYTE* optional, out
' cbMax : DWORD
' cbOff : DWORD
Declare PtrSafe Function DdeGetData Lib "user32" ( _
    ByVal hData As LongPtr, _
    ByVal pDst As LongPtr, _
    ByVal cbMax As Long, _
    ByVal cbOff As Long) As Long
' VBA7前提(PtrSafe)。32bit Office では LongPtr→Long。Integer=16bit / Long=32bit / LongLong=64bit。

import ctypes
from ctypes import wintypes

DdeGetData = ctypes.windll.user32.DdeGetData
DdeGetData.restype = wintypes.DWORD
DdeGetData.argtypes = [
    wintypes.HANDLE,  # hData : HDDEDATA
    ctypes.POINTER(ctypes.c_ubyte),  # pDst : BYTE* optional, out
    wintypes.DWORD,  # cbMax : DWORD
    wintypes.DWORD,  # cbOff : DWORD
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('USER32.dll')
DdeGetData = Fiddle::Function.new(
  lib['DdeGetData'],
  [
    Fiddle::TYPE_VOIDP,  # hData : HDDEDATA
    Fiddle::TYPE_VOIDP,  # pDst : BYTE* optional, out
    -Fiddle::TYPE_INT,  # cbMax : DWORD
    -Fiddle::TYPE_INT,  # cbOff : DWORD
  ],
  -Fiddle::TYPE_INT)

#[link(name = "user32")]
extern "system" {
    fn DdeGetData(
        hData: *mut core::ffi::c_void,  // HDDEDATA
        pDst: *mut u8,  // BYTE* optional, out
        cbMax: u32,  // DWORD
        cbOff: u32  // DWORD
    ) -> u32;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("USER32.dll")]
public static extern uint DdeGetData(IntPtr hData, IntPtr pDst, uint cbMax, uint cbOff);
"@
$api = Add-Type -MemberDefinition $sig -Name 'USER32_DdeGetData' -Namespace Win32 -PassThru
# $api::DdeGetData(hData, pDst, cbMax, cbOff)

#uselib "USER32.dll"
#func global DdeGetData "DdeGetData" sptr, sptr, sptr, sptr
; DdeGetData hData, varptr(pDst), cbMax, cbOff   ; 戻り値は stat
; hData : HDDEDATA -> "sptr"
; pDst : BYTE* optional, out -> "sptr"
; cbMax : DWORD -> "sptr"
; cbOff : DWORD -> "sptr"
; ※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 DdeGetData "DdeGetData" sptr, var, int, int
; res = DdeGetData(hData, pDst, cbMax, cbOff)
; hData : HDDEDATA -> "sptr"
; pDst : BYTE* optional, out -> "var"
; cbMax : DWORD -> "int"
; cbOff : DWORD -> "int"
; ※出力/バッファ引数は var 方式(変数を直接渡す)。varptr 方式にも切替可。

; DWORD DdeGetData(HDDEDATA hData, BYTE* pDst, DWORD cbMax, DWORD cbOff)
#uselib "USER32.dll"
#cfunc global DdeGetData "DdeGetData" intptr, var, int, int
; res = DdeGetData(hData, pDst, cbMax, cbOff)
; hData : HDDEDATA -> "intptr"
; pDst : BYTE* optional, out -> "var"
; cbMax : DWORD -> "int"
; cbOff : DWORD -> "int"
; ※出力/バッファ引数は var 方式(変数を直接渡す)。varptr 方式にも切替可。

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

var (
	user32 = windows.NewLazySystemDLL("USER32.dll")
	procDdeGetData = user32.NewProc("DdeGetData")
)

// hData (HDDEDATA), pDst (BYTE* optional, out), cbMax (DWORD), cbOff (DWORD)
r1, _, err := procDdeGetData.Call(
	uintptr(hData),
	uintptr(pDst),
	uintptr(cbMax),
	uintptr(cbOff),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // DWORD

function DdeGetData(
  hData: THandle;   // HDDEDATA
  pDst: Pointer;   // BYTE* optional, out
  cbMax: DWORD;   // DWORD
  cbOff: DWORD   // DWORD
): DWORD; stdcall;
  external 'USER32.dll' name 'DdeGetData';

result := DllCall("USER32\DdeGetData"
    , "Ptr", hData   ; HDDEDATA
    , "Ptr", pDst   ; BYTE* optional, out
    , "UInt", cbMax   ; DWORD
    , "UInt", cbOff   ; DWORD
    , "UInt")   ; return: DWORD

●DdeGetData(hData, pDst, cbMax, cbOff) = DLL("USER32.dll", "dword DdeGetData(void*, void*, dword, dword)")
# 呼び出し: DdeGetData(hData, pDst, cbMax, cbOff)
# hData : HDDEDATA -> "void*"
# pDst : BYTE* optional, out -> "void*"
# cbMax : DWORD -> "dword"
# cbOff : 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)。