GetDateFormatA

// KERNEL32.dll  (ANSI / -A)
#include <windows.h>

INT GetDateFormatA(
    DWORD Locale,
    DWORD dwFlags,
    const SYSTEMTIME* lpDate,   // optional
    LPCSTR lpFormat,   // optional
    LPSTR lpDateStr,   // optional
    INT cchDate
);

<DllImport("KERNEL32.dll", CharSet:=CharSet.Ansi, SetLastError:=True, ExactSpelling:=True)>
Public Shared Function GetDateFormatA(
    Locale As UInteger,   ' DWORD
    dwFlags As UInteger,   ' DWORD
    lpDate As IntPtr,   ' SYSTEMTIME* optional
    <MarshalAs(UnmanagedType.LPStr)> lpFormat As String,   ' LPCSTR optional
    <MarshalAs(UnmanagedType.LPStr)> lpDateStr As System.Text.StringBuilder,   ' LPSTR optional, out
    cchDate As Integer   ' INT
) As Integer
End Function

' Locale : DWORD
' dwFlags : DWORD
' lpDate : SYSTEMTIME* optional
' lpFormat : LPCSTR optional
' lpDateStr : LPSTR optional, out
' cchDate : INT
Declare PtrSafe Function GetDateFormatA Lib "kernel32" ( _
    ByVal Locale As Long, _
    ByVal dwFlags As Long, _
    ByVal lpDate As LongPtr, _
    ByVal lpFormat As String, _
    ByVal lpDateStr As String, _
    ByVal cchDate 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

GetDateFormatA = ctypes.windll.kernel32.GetDateFormatA
GetDateFormatA.restype = ctypes.c_int
GetDateFormatA.argtypes = [
    wintypes.DWORD,  # Locale : DWORD
    wintypes.DWORD,  # dwFlags : DWORD
    ctypes.c_void_p,  # lpDate : SYSTEMTIME* optional
    wintypes.LPCSTR,  # lpFormat : LPCSTR optional
    wintypes.LPSTR,  # lpDateStr : LPSTR optional, out
    ctypes.c_int,  # cchDate : INT
]
# GetLastError: use ctypes.GetLastError() (or ctypes.WinDLL(use_last_error=True))

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('KERNEL32.dll')
GetDateFormatA = Fiddle::Function.new(
  lib['GetDateFormatA'],
  [
    -Fiddle::TYPE_INT,  # Locale : DWORD
    -Fiddle::TYPE_INT,  # dwFlags : DWORD
    Fiddle::TYPE_VOIDP,  # lpDate : SYSTEMTIME* optional
    Fiddle::TYPE_VOIDP,  # lpFormat : LPCSTR optional
    Fiddle::TYPE_VOIDP,  # lpDateStr : LPSTR optional, out
    Fiddle::TYPE_INT,  # cchDate : INT
  ],
  Fiddle::TYPE_INT)

#[link(name = "kernel32")]
extern "system" {
    fn GetDateFormatA(
        Locale: u32,  // DWORD
        dwFlags: u32,  // DWORD
        lpDate: *const SYSTEMTIME,  // SYSTEMTIME* optional
        lpFormat: *const u8,  // LPCSTR optional
        lpDateStr: *mut u8,  // LPSTR optional, out
        cchDate: i32  // INT
    ) -> i32;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("KERNEL32.dll", CharSet = CharSet.Ansi, SetLastError = true)]
public static extern int GetDateFormatA(uint Locale, uint dwFlags, IntPtr lpDate, [MarshalAs(UnmanagedType.LPStr)] string lpFormat, [MarshalAs(UnmanagedType.LPStr)] System.Text.StringBuilder lpDateStr, int cchDate);
"@
$api = Add-Type -MemberDefinition $sig -Name 'KERNEL32_GetDateFormatA' -Namespace Win32 -PassThru
# $api::GetDateFormatA(Locale, dwFlags, lpDate, lpFormat, lpDateStr, cchDate)

#uselib "KERNEL32.dll"
#func global GetDateFormatA "GetDateFormatA" sptr, sptr, sptr, sptr, sptr, sptr
; GetDateFormatA Locale, dwFlags, varptr(lpDate), lpFormat, varptr(lpDateStr), cchDate   ; 戻り値は stat
; Locale : DWORD -> "sptr"
; dwFlags : DWORD -> "sptr"
; lpDate : SYSTEMTIME* optional -> "sptr"
; lpFormat : LPCSTR optional -> "sptr"
; lpDateStr : LPSTR optional, out -> "sptr"
; cchDate : INT -> "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 GetDateFormatA "GetDateFormatA" int, int, var, str, var, int
; res = GetDateFormatA(Locale, dwFlags, lpDate, lpFormat, lpDateStr, cchDate)
; Locale : DWORD -> "int"
; dwFlags : DWORD -> "int"
; lpDate : SYSTEMTIME* optional -> "var"
; lpFormat : LPCSTR optional -> "str"
; lpDateStr : LPSTR optional, out -> "var"
; cchDate : INT -> "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 GetDateFormatA(DWORD Locale, DWORD dwFlags, SYSTEMTIME* lpDate, LPCSTR lpFormat, LPSTR lpDateStr, INT cchDate)
#uselib "KERNEL32.dll"
#cfunc global GetDateFormatA "GetDateFormatA" int, int, var, str, var, int
; res = GetDateFormatA(Locale, dwFlags, lpDate, lpFormat, lpDateStr, cchDate)
; Locale : DWORD -> "int"
; dwFlags : DWORD -> "int"
; lpDate : SYSTEMTIME* optional -> "var"
; lpFormat : LPCSTR optional -> "str"
; lpDateStr : LPSTR optional, out -> "var"
; cchDate : INT -> "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 (
	kernel32 = windows.NewLazySystemDLL("KERNEL32.dll")
	procGetDateFormatA = kernel32.NewProc("GetDateFormatA")
)

// Locale (DWORD), dwFlags (DWORD), lpDate (SYSTEMTIME* optional), lpFormat (LPCSTR optional), lpDateStr (LPSTR optional, out), cchDate (INT)
r1, _, err := procGetDateFormatA.Call(
	uintptr(Locale),
	uintptr(dwFlags),
	uintptr(lpDate),
	uintptr(unsafe.Pointer(windows.BytePtrFromString(lpFormat))),
	uintptr(lpDateStr),
	uintptr(cchDate),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // INT

function GetDateFormatA(
  Locale: DWORD;   // DWORD
  dwFlags: DWORD;   // DWORD
  lpDate: Pointer;   // SYSTEMTIME* optional
  lpFormat: PAnsiChar;   // LPCSTR optional
  lpDateStr: PAnsiChar;   // LPSTR optional, out
  cchDate: Integer   // INT
): Integer; stdcall;
  external 'KERNEL32.dll' name 'GetDateFormatA';

result := DllCall("KERNEL32\GetDateFormatA"
    , "UInt", Locale   ; DWORD
    , "UInt", dwFlags   ; DWORD
    , "Ptr", lpDate   ; SYSTEMTIME* optional
    , "AStr", lpFormat   ; LPCSTR optional
    , "Ptr", lpDateStr   ; LPSTR optional, out
    , "Int", cchDate   ; INT
    , "Int")   ; return: INT

●GetDateFormatA(Locale, dwFlags, lpDate, lpFormat, lpDateStr, cchDate) = DLL("KERNEL32.dll", "int GetDateFormatA(dword, dword, void*, char*, char*, int)")
# 呼び出し: GetDateFormatA(Locale, dwFlags, lpDate, lpFormat, lpDateStr, cchDate)
# Locale : DWORD -> "dword"
# dwFlags : DWORD -> "dword"
# lpDate : SYSTEMTIME* optional -> "void*"
# lpFormat : LPCSTR optional -> "char*"
# lpDateStr : LPSTR optional, out -> "char*"
# cchDate : INT -> "int"
# 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)。