GetTimeZoneInformation

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

DWORD GetTimeZoneInformation(
    TIME_ZONE_INFORMATION* lpTimeZoneInformation
);

<DllImport("KERNEL32.dll", SetLastError:=True, ExactSpelling:=True)>
Public Shared Function GetTimeZoneInformation(
    lpTimeZoneInformation As IntPtr   ' TIME_ZONE_INFORMATION* out
) As UInteger
End Function

' lpTimeZoneInformation : TIME_ZONE_INFORMATION* out
Declare PtrSafe Function GetTimeZoneInformation Lib "kernel32" ( _
    ByVal lpTimeZoneInformation As LongPtr) As Long
' VBA7前提(PtrSafe)。32bit Office では LongPtr→Long。Integer=16bit / Long=32bit / LongLong=64bit。

import ctypes
from ctypes import wintypes

GetTimeZoneInformation = ctypes.windll.kernel32.GetTimeZoneInformation
GetTimeZoneInformation.restype = wintypes.DWORD
GetTimeZoneInformation.argtypes = [
    ctypes.c_void_p,  # lpTimeZoneInformation : TIME_ZONE_INFORMATION* out
]
# GetLastError: use ctypes.GetLastError() (or ctypes.WinDLL(use_last_error=True))

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('KERNEL32.dll')
GetTimeZoneInformation = Fiddle::Function.new(
  lib['GetTimeZoneInformation'],
  [
    Fiddle::TYPE_VOIDP,  # lpTimeZoneInformation : TIME_ZONE_INFORMATION* out
  ],
  -Fiddle::TYPE_INT)

#[link(name = "kernel32")]
extern "system" {
    fn GetTimeZoneInformation(
        lpTimeZoneInformation: *mut TIME_ZONE_INFORMATION  // TIME_ZONE_INFORMATION* out
    ) -> u32;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("KERNEL32.dll", SetLastError = true)]
public static extern uint GetTimeZoneInformation(IntPtr lpTimeZoneInformation);
"@
$api = Add-Type -MemberDefinition $sig -Name 'KERNEL32_GetTimeZoneInformation' -Namespace Win32 -PassThru
# $api::GetTimeZoneInformation(lpTimeZoneInformation)

#uselib "KERNEL32.dll"
#func global GetTimeZoneInformation "GetTimeZoneInformation" sptr
; GetTimeZoneInformation varptr(lpTimeZoneInformation)   ; 戻り値は stat
; lpTimeZoneInformation : TIME_ZONE_INFORMATION* out -> "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 GetTimeZoneInformation "GetTimeZoneInformation" var
; res = GetTimeZoneInformation(lpTimeZoneInformation)
; lpTimeZoneInformation : TIME_ZONE_INFORMATION* out -> "var"
; ※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 GetTimeZoneInformation(TIME_ZONE_INFORMATION* lpTimeZoneInformation)
#uselib "KERNEL32.dll"
#cfunc global GetTimeZoneInformation "GetTimeZoneInformation" var
; res = GetTimeZoneInformation(lpTimeZoneInformation)
; lpTimeZoneInformation : TIME_ZONE_INFORMATION* out -> "var"
; ※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 (
	kernel32 = windows.NewLazySystemDLL("KERNEL32.dll")
	procGetTimeZoneInformation = kernel32.NewProc("GetTimeZoneInformation")
)

// lpTimeZoneInformation (TIME_ZONE_INFORMATION* out)
r1, _, err := procGetTimeZoneInformation.Call(
	uintptr(lpTimeZoneInformation),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // DWORD

function GetTimeZoneInformation(
  lpTimeZoneInformation: Pointer   // TIME_ZONE_INFORMATION* out
): DWORD; stdcall;
  external 'KERNEL32.dll' name 'GetTimeZoneInformation';

result := DllCall("KERNEL32\GetTimeZoneInformation"
    , "Ptr", lpTimeZoneInformation   ; TIME_ZONE_INFORMATION* out
    , "UInt")   ; return: DWORD

●GetTimeZoneInformation(lpTimeZoneInformation) = DLL("KERNEL32.dll", "dword GetTimeZoneInformation(void*)")
# 呼び出し: GetTimeZoneInformation(lpTimeZoneInformation)
# lpTimeZoneInformation : TIME_ZONE_INFORMATION* out -> "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)。