ToUnicode

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

INT ToUnicode(
    DWORD wVirtKey,
    DWORD wScanCode,
    const BYTE* lpKeyState,   // optional
    LPWSTR pwszBuff,
    INT cchBuff,
    DWORD wFlags
);

<DllImport("USER32.dll", ExactSpelling:=True)>
Public Shared Function ToUnicode(
    wVirtKey As UInteger,   ' DWORD
    wScanCode As UInteger,   ' DWORD
    lpKeyState As IntPtr,   ' BYTE* optional
    <MarshalAs(UnmanagedType.LPWStr)> pwszBuff As System.Text.StringBuilder,   ' LPWSTR out
    cchBuff As Integer,   ' INT
    wFlags As UInteger   ' DWORD
) As Integer
End Function

' wVirtKey : DWORD
' wScanCode : DWORD
' lpKeyState : BYTE* optional
' pwszBuff : LPWSTR out
' cchBuff : INT
' wFlags : DWORD
Declare PtrSafe Function ToUnicode Lib "user32" ( _
    ByVal wVirtKey As Long, _
    ByVal wScanCode As Long, _
    ByVal lpKeyState As LongPtr, _
    ByVal pwszBuff As LongPtr, _
    ByVal cchBuff As Long, _
    ByVal wFlags 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

ToUnicode = ctypes.windll.user32.ToUnicode
ToUnicode.restype = ctypes.c_int
ToUnicode.argtypes = [
    wintypes.DWORD,  # wVirtKey : DWORD
    wintypes.DWORD,  # wScanCode : DWORD
    ctypes.POINTER(ctypes.c_ubyte),  # lpKeyState : BYTE* optional
    wintypes.LPWSTR,  # pwszBuff : LPWSTR out
    ctypes.c_int,  # cchBuff : INT
    wintypes.DWORD,  # wFlags : DWORD
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('USER32.dll')
ToUnicode = Fiddle::Function.new(
  lib['ToUnicode'],
  [
    -Fiddle::TYPE_INT,  # wVirtKey : DWORD
    -Fiddle::TYPE_INT,  # wScanCode : DWORD
    Fiddle::TYPE_VOIDP,  # lpKeyState : BYTE* optional
    Fiddle::TYPE_VOIDP,  # pwszBuff : LPWSTR out
    Fiddle::TYPE_INT,  # cchBuff : INT
    -Fiddle::TYPE_INT,  # wFlags : DWORD
  ],
  Fiddle::TYPE_INT)

#[link(name = "user32")]
extern "system" {
    fn ToUnicode(
        wVirtKey: u32,  // DWORD
        wScanCode: u32,  // DWORD
        lpKeyState: *const u8,  // BYTE* optional
        pwszBuff: *mut u16,  // LPWSTR out
        cchBuff: i32,  // INT
        wFlags: u32  // DWORD
    ) -> i32;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("USER32.dll")]
public static extern int ToUnicode(uint wVirtKey, uint wScanCode, IntPtr lpKeyState, [MarshalAs(UnmanagedType.LPWStr)] System.Text.StringBuilder pwszBuff, int cchBuff, uint wFlags);
"@
$api = Add-Type -MemberDefinition $sig -Name 'USER32_ToUnicode' -Namespace Win32 -PassThru
# $api::ToUnicode(wVirtKey, wScanCode, lpKeyState, pwszBuff, cchBuff, wFlags)

#uselib "USER32.dll"
#func global ToUnicode "ToUnicode" sptr, sptr, sptr, sptr, sptr, sptr
; ToUnicode wVirtKey, wScanCode, varptr(lpKeyState), varptr(pwszBuff), cchBuff, wFlags   ; 戻り値は stat
; wVirtKey : DWORD -> "sptr"
; wScanCode : DWORD -> "sptr"
; lpKeyState : BYTE* optional -> "sptr"
; pwszBuff : LPWSTR out -> "sptr"
; cchBuff : INT -> "sptr"
; wFlags : 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 ToUnicode "ToUnicode" int, int, var, var, int, int
; res = ToUnicode(wVirtKey, wScanCode, lpKeyState, pwszBuff, cchBuff, wFlags)
; wVirtKey : DWORD -> "int"
; wScanCode : DWORD -> "int"
; lpKeyState : BYTE* optional -> "var"
; pwszBuff : LPWSTR out -> "var"
; cchBuff : INT -> "int"
; wFlags : 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。

; INT ToUnicode(DWORD wVirtKey, DWORD wScanCode, BYTE* lpKeyState, LPWSTR pwszBuff, INT cchBuff, DWORD wFlags)
#uselib "USER32.dll"
#cfunc global ToUnicode "ToUnicode" int, int, var, var, int, int
; res = ToUnicode(wVirtKey, wScanCode, lpKeyState, pwszBuff, cchBuff, wFlags)
; wVirtKey : DWORD -> "int"
; wScanCode : DWORD -> "int"
; lpKeyState : BYTE* optional -> "var"
; pwszBuff : LPWSTR out -> "var"
; cchBuff : INT -> "int"
; wFlags : 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")
	procToUnicode = user32.NewProc("ToUnicode")
)

// wVirtKey (DWORD), wScanCode (DWORD), lpKeyState (BYTE* optional), pwszBuff (LPWSTR out), cchBuff (INT), wFlags (DWORD)
r1, _, err := procToUnicode.Call(
	uintptr(wVirtKey),
	uintptr(wScanCode),
	uintptr(lpKeyState),
	uintptr(pwszBuff),
	uintptr(cchBuff),
	uintptr(wFlags),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // INT

function ToUnicode(
  wVirtKey: DWORD;   // DWORD
  wScanCode: DWORD;   // DWORD
  lpKeyState: Pointer;   // BYTE* optional
  pwszBuff: PWideChar;   // LPWSTR out
  cchBuff: Integer;   // INT
  wFlags: DWORD   // DWORD
): Integer; stdcall;
  external 'USER32.dll' name 'ToUnicode';

result := DllCall("USER32\ToUnicode"
    , "UInt", wVirtKey   ; DWORD
    , "UInt", wScanCode   ; DWORD
    , "Ptr", lpKeyState   ; BYTE* optional
    , "Ptr", pwszBuff   ; LPWSTR out
    , "Int", cchBuff   ; INT
    , "UInt", wFlags   ; DWORD
    , "Int")   ; return: INT

●ToUnicode(wVirtKey, wScanCode, lpKeyState, pwszBuff, cchBuff, wFlags) = DLL("USER32.dll", "int ToUnicode(dword, dword, void*, char*, int, dword)")
# 呼び出し: ToUnicode(wVirtKey, wScanCode, lpKeyState, pwszBuff, cchBuff, wFlags)
# wVirtKey : DWORD -> "dword"
# wScanCode : DWORD -> "dword"
# lpKeyState : BYTE* optional -> "void*"
# pwszBuff : LPWSTR out -> "char*"
# cchBuff : INT -> "int"
# wFlags : 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)。