AddDllDirectory

// KERNEL32.dll
#include <windows.h>

void* AddDllDirectory(
    LPCWSTR NewDirectory
);

<DllImport("KERNEL32.dll", SetLastError:=True, ExactSpelling:=True)>
Public Shared Function AddDllDirectory(
    <MarshalAs(UnmanagedType.LPWStr)> NewDirectory As String   ' LPCWSTR
) As IntPtr
End Function

' NewDirectory : LPCWSTR
Declare PtrSafe Function AddDllDirectory Lib "kernel32" ( _
    ByVal NewDirectory 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

AddDllDirectory = ctypes.windll.kernel32.AddDllDirectory
AddDllDirectory.restype = ctypes.c_void_p
AddDllDirectory.argtypes = [
    wintypes.LPCWSTR,  # NewDirectory : LPCWSTR
]
# GetLastError: use ctypes.GetLastError() (or ctypes.WinDLL(use_last_error=True))

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('KERNEL32.dll')
AddDllDirectory = Fiddle::Function.new(
  lib['AddDllDirectory'],
  [
    Fiddle::TYPE_VOIDP,  # NewDirectory : LPCWSTR
  ],
  Fiddle::TYPE_VOIDP)

#[link(name = "kernel32")]
extern "system" {
    fn AddDllDirectory(
        NewDirectory: *const u16  // LPCWSTR
    ) -> *mut ();
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("KERNEL32.dll", SetLastError = true)]
public static extern IntPtr AddDllDirectory([MarshalAs(UnmanagedType.LPWStr)] string NewDirectory);
"@
$api = Add-Type -MemberDefinition $sig -Name 'KERNEL32_AddDllDirectory' -Namespace Win32 -PassThru
# $api::AddDllDirectory(NewDirectory)

#uselib "KERNEL32.dll"
#func global AddDllDirectory "AddDllDirectory" sptr
; AddDllDirectory NewDirectory   ; 戻り値は stat
; NewDirectory : LPCWSTR -> "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 "KERNEL32.dll"
#cfunc global AddDllDirectory "AddDllDirectory" wstr
; res = AddDllDirectory(NewDirectory)
; NewDirectory : LPCWSTR -> "wstr"

; void* AddDllDirectory(LPCWSTR NewDirectory)
#uselib "KERNEL32.dll"
#cfunc global AddDllDirectory "AddDllDirectory" wstr
; res = AddDllDirectory(NewDirectory)
; NewDirectory : LPCWSTR -> "wstr"

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

var (
	kernel32 = windows.NewLazySystemDLL("KERNEL32.dll")
	procAddDllDirectory = kernel32.NewProc("AddDllDirectory")
)

// NewDirectory (LPCWSTR)
r1, _, err := procAddDllDirectory.Call(
	uintptr(unsafe.Pointer(windows.StringToUTF16Ptr(NewDirectory))),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // void*

function AddDllDirectory(
  NewDirectory: PWideChar   // LPCWSTR
): Pointer; stdcall;
  external 'KERNEL32.dll' name 'AddDllDirectory';

result := DllCall("KERNEL32\AddDllDirectory"
    , "WStr", NewDirectory   ; LPCWSTR
    , "Ptr")   ; return: void*

●AddDllDirectory(NewDirectory) = DLL("KERNEL32.dll", "void* AddDllDirectory(char*)")
# 呼び出し: AddDllDirectory(NewDirectory)
# NewDirectory : 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)。