RtlInitUnicodeString

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

void RtlInitUnicodeString(
    UNICODE_STRING* DestinationString,
    LPCWSTR SourceString
);

<DllImport("ntdll.dll", ExactSpelling:=True)>
Public Shared Sub RtlInitUnicodeString(
    DestinationString As IntPtr,   ' UNICODE_STRING* in/out
    <MarshalAs(UnmanagedType.LPWStr)> SourceString As String   ' LPCWSTR
)
End Sub

' DestinationString : UNICODE_STRING* in/out
' SourceString : LPCWSTR
Declare PtrSafe Sub RtlInitUnicodeString Lib "ntdll" ( _
    ByVal DestinationString As LongPtr, _
    ByVal SourceString As LongPtr)
' VBA7前提(PtrSafe)。32bit Office では LongPtr→Long。Integer=16bit / Long=32bit / LongLong=64bit。

import ctypes
from ctypes import wintypes

RtlInitUnicodeString = ctypes.windll.ntdll.RtlInitUnicodeString
RtlInitUnicodeString.restype = None
RtlInitUnicodeString.argtypes = [
    ctypes.c_void_p,  # DestinationString : UNICODE_STRING* in/out
    wintypes.LPCWSTR,  # SourceString : LPCWSTR
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('ntdll.dll')
RtlInitUnicodeString = Fiddle::Function.new(
  lib['RtlInitUnicodeString'],
  [
    Fiddle::TYPE_VOIDP,  # DestinationString : UNICODE_STRING* in/out
    Fiddle::TYPE_VOIDP,  # SourceString : LPCWSTR
  ],
  Fiddle::TYPE_VOID)

#[link(name = "ntdll")]
extern "system" {
    fn RtlInitUnicodeString(
        DestinationString: *mut UNICODE_STRING,  // UNICODE_STRING* in/out
        SourceString: *const u16  // LPCWSTR
    );
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("ntdll.dll")]
public static extern void RtlInitUnicodeString(IntPtr DestinationString, [MarshalAs(UnmanagedType.LPWStr)] string SourceString);
"@
$api = Add-Type -MemberDefinition $sig -Name 'ntdll_RtlInitUnicodeString' -Namespace Win32 -PassThru
# $api::RtlInitUnicodeString(DestinationString, SourceString)

#uselib "ntdll.dll"
#func global RtlInitUnicodeString "RtlInitUnicodeString" sptr, sptr
; RtlInitUnicodeString varptr(DestinationString), SourceString
; DestinationString : UNICODE_STRING* in/out -> "sptr"
; SourceString : LPCWSTR -> "sptr"

#uselib "ntdll.dll"
#func global RtlInitUnicodeString "RtlInitUnicodeString" var, wstr
; RtlInitUnicodeString DestinationString, SourceString
; DestinationString : UNICODE_STRING* in/out -> "var"
; SourceString : LPCWSTR -> "wstr"
; ※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。

; void RtlInitUnicodeString(UNICODE_STRING* DestinationString, LPCWSTR SourceString)
#uselib "ntdll.dll"
#func global RtlInitUnicodeString "RtlInitUnicodeString" var, wstr
; RtlInitUnicodeString DestinationString, SourceString
; DestinationString : UNICODE_STRING* in/out -> "var"
; SourceString : LPCWSTR -> "wstr"
; ※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 (
	ntdll = windows.NewLazySystemDLL("ntdll.dll")
	procRtlInitUnicodeString = ntdll.NewProc("RtlInitUnicodeString")
)

// DestinationString (UNICODE_STRING* in/out), SourceString (LPCWSTR)
r1, _, err := procRtlInitUnicodeString.Call(
	uintptr(DestinationString),
	uintptr(unsafe.Pointer(windows.StringToUTF16Ptr(SourceString))),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // void

procedure RtlInitUnicodeString(
  DestinationString: Pointer;   // UNICODE_STRING* in/out
  SourceString: PWideChar   // LPCWSTR
); stdcall;
  external 'ntdll.dll' name 'RtlInitUnicodeString';

result := DllCall("ntdll\RtlInitUnicodeString"
    , "Ptr", DestinationString   ; UNICODE_STRING* in/out
    , "WStr", SourceString   ; LPCWSTR
    , "Int")   ; return: void

●RtlInitUnicodeString(DestinationString, SourceString) = DLL("ntdll.dll", "int RtlInitUnicodeString(void*, char*)")
# 呼び出し: RtlInitUnicodeString(DestinationString, SourceString)
# DestinationString : UNICODE_STRING* in/out -> "void*"
# SourceString : LPCWSTR -> "char*"
# 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)。