SHFormatDateTimeW

// SHLWAPI.dll  (Unicode / -W)
#include <windows.h>

INT SHFormatDateTimeW(
    const FILETIME* pft,
    DWORD* pdwFlags,   // optional
    LPWSTR pszBuf,
    DWORD cchBuf
);

<DllImport("SHLWAPI.dll", CharSet:=CharSet.Unicode, ExactSpelling:=True)>
Public Shared Function SHFormatDateTimeW(
    pft As IntPtr,   ' FILETIME*
    pdwFlags As IntPtr,   ' DWORD* optional, in/out
    <MarshalAs(UnmanagedType.LPWStr)> pszBuf As System.Text.StringBuilder,   ' LPWSTR out
    cchBuf As UInteger   ' DWORD
) As Integer
End Function

' pft : FILETIME*
' pdwFlags : DWORD* optional, in/out
' pszBuf : LPWSTR out
' cchBuf : DWORD
Declare PtrSafe Function SHFormatDateTimeW Lib "shlwapi" ( _
    ByVal pft As LongPtr, _
    ByVal pdwFlags As LongPtr, _
    ByVal pszBuf As LongPtr, _
    ByVal cchBuf As Long) As Long
' Unicode(W): 文字列は ByVal As LongPtr とし StrPtr(unicodeStr) を渡す
' VBA7前提(PtrSafe)。32bit Office では LongPtr→Long。Integer=16bit / Long=32bit / LongLong=64bit。

import ctypes
from ctypes import wintypes

SHFormatDateTimeW = ctypes.windll.shlwapi.SHFormatDateTimeW
SHFormatDateTimeW.restype = ctypes.c_int
SHFormatDateTimeW.argtypes = [
    ctypes.c_void_p,  # pft : FILETIME*
    ctypes.POINTER(wintypes.DWORD),  # pdwFlags : DWORD* optional, in/out
    wintypes.LPWSTR,  # pszBuf : LPWSTR out
    wintypes.DWORD,  # cchBuf : DWORD
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('SHLWAPI.dll')
SHFormatDateTimeW = Fiddle::Function.new(
  lib['SHFormatDateTimeW'],
  [
    Fiddle::TYPE_VOIDP,  # pft : FILETIME*
    Fiddle::TYPE_VOIDP,  # pdwFlags : DWORD* optional, in/out
    Fiddle::TYPE_VOIDP,  # pszBuf : LPWSTR out
    -Fiddle::TYPE_INT,  # cchBuf : DWORD
  ],
  Fiddle::TYPE_INT)
# Wide strings: pass str.encode("UTF-16LE") + "\x00\x00"

#[link(name = "shlwapi")]
extern "system" {
    fn SHFormatDateTimeW(
        pft: *const FILETIME,  // FILETIME*
        pdwFlags: *mut u32,  // DWORD* optional, in/out
        pszBuf: *mut u16,  // LPWSTR out
        cchBuf: u32  // DWORD
    ) -> i32;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("SHLWAPI.dll", CharSet = CharSet.Unicode)]
public static extern int SHFormatDateTimeW(IntPtr pft, IntPtr pdwFlags, [MarshalAs(UnmanagedType.LPWStr)] System.Text.StringBuilder pszBuf, uint cchBuf);
"@
$api = Add-Type -MemberDefinition $sig -Name 'SHLWAPI_SHFormatDateTimeW' -Namespace Win32 -PassThru
# $api::SHFormatDateTimeW(pft, pdwFlags, pszBuf, cchBuf)

#uselib "SHLWAPI.dll"
#func global SHFormatDateTimeW "SHFormatDateTimeW" wptr, wptr, wptr, wptr
; SHFormatDateTimeW varptr(pft), varptr(pdwFlags), varptr(pszBuf), cchBuf   ; 戻り値は stat
; pft : FILETIME* -> "wptr"
; pdwFlags : DWORD* optional, in/out -> "wptr"
; pszBuf : LPWSTR out -> "wptr"
; cchBuf : DWORD -> "wptr"
; ※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 "SHLWAPI.dll"
#cfunc global SHFormatDateTimeW "SHFormatDateTimeW" var, var, var, int
; res = SHFormatDateTimeW(pft, pdwFlags, pszBuf, cchBuf)
; pft : FILETIME* -> "var"
; pdwFlags : DWORD* optional, in/out -> "var"
; pszBuf : LPWSTR out -> "var"
; cchBuf : 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 SHFormatDateTimeW(FILETIME* pft, DWORD* pdwFlags, LPWSTR pszBuf, DWORD cchBuf)
#uselib "SHLWAPI.dll"
#cfunc global SHFormatDateTimeW "SHFormatDateTimeW" var, var, var, int
; res = SHFormatDateTimeW(pft, pdwFlags, pszBuf, cchBuf)
; pft : FILETIME* -> "var"
; pdwFlags : DWORD* optional, in/out -> "var"
; pszBuf : LPWSTR out -> "var"
; cchBuf : 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 (
	shlwapi = windows.NewLazySystemDLL("SHLWAPI.dll")
	procSHFormatDateTimeW = shlwapi.NewProc("SHFormatDateTimeW")
)

// pft (FILETIME*), pdwFlags (DWORD* optional, in/out), pszBuf (LPWSTR out), cchBuf (DWORD)
r1, _, err := procSHFormatDateTimeW.Call(
	uintptr(pft),
	uintptr(pdwFlags),
	uintptr(pszBuf),
	uintptr(cchBuf),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // INT

function SHFormatDateTimeW(
  pft: Pointer;   // FILETIME*
  pdwFlags: Pointer;   // DWORD* optional, in/out
  pszBuf: PWideChar;   // LPWSTR out
  cchBuf: DWORD   // DWORD
): Integer; stdcall;
  external 'SHLWAPI.dll' name 'SHFormatDateTimeW';

result := DllCall("SHLWAPI\SHFormatDateTimeW"
    , "Ptr", pft   ; FILETIME*
    , "Ptr", pdwFlags   ; DWORD* optional, in/out
    , "Ptr", pszBuf   ; LPWSTR out
    , "UInt", cchBuf   ; DWORD
    , "Int")   ; return: INT

●SHFormatDateTimeW(pft, pdwFlags, pszBuf, cchBuf) = DLL("SHLWAPI.dll", "int SHFormatDateTimeW(void*, void*, char*, dword)")
# 呼び出し: SHFormatDateTimeW(pft, pdwFlags, pszBuf, cchBuf)
# pft : FILETIME* -> "void*"
# pdwFlags : DWORD* optional, in/out -> "void*"
# pszBuf : LPWSTR out -> "char*"
# cchBuf : 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)。
# ※-W(Unicode)関数。なでしこ1はANSIのため -A 版の利用を推奨。