uloc_getLocaleForLCID

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

INT uloc_getLocaleForLCID(
    DWORD hostID,
    LPSTR locale,
    INT localeCapacity,
    UErrorCode* status
);

<DllImport("icuuc.dll", ExactSpelling:=True, CallingConvention:=CallingConvention.Cdecl)>
Public Shared Function uloc_getLocaleForLCID(
    hostID As UInteger,   ' DWORD
    <MarshalAs(UnmanagedType.LPStr)> locale As String,   ' LPSTR
    localeCapacity As Integer,   ' INT
    ByRef status As Integer   ' UErrorCode* in/out
) As Integer
End Function

' hostID : DWORD
' locale : LPSTR
' localeCapacity : INT
' status : UErrorCode* in/out
Declare PtrSafe Function uloc_getLocaleForLCID Lib "icuuc" ( _
    ByVal hostID As Long, _
    ByVal locale As String, _
    ByVal localeCapacity As Long, _
    ByRef status 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

uloc_getLocaleForLCID = ctypes.cdll.icuuc.uloc_getLocaleForLCID
uloc_getLocaleForLCID.restype = ctypes.c_int
uloc_getLocaleForLCID.argtypes = [
    wintypes.DWORD,  # hostID : DWORD
    wintypes.LPCSTR,  # locale : LPSTR
    ctypes.c_int,  # localeCapacity : INT
    ctypes.c_void_p,  # status : UErrorCode* in/out
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('icuuc.dll')
uloc_getLocaleForLCID = Fiddle::Function.new(
  lib['uloc_getLocaleForLCID'],
  [
    -Fiddle::TYPE_INT,  # hostID : DWORD
    Fiddle::TYPE_VOIDP,  # locale : LPSTR
    Fiddle::TYPE_INT,  # localeCapacity : INT
    Fiddle::TYPE_VOIDP,  # status : UErrorCode* in/out
  ],
  Fiddle::TYPE_INT, Fiddle::Function::CDECL)

#[link(name = "icuuc")]
extern "C" {
    fn uloc_getLocaleForLCID(
        hostID: u32,  // DWORD
        locale: *mut u8,  // LPSTR
        localeCapacity: i32,  // INT
        status: *mut i32  // UErrorCode* in/out
    ) -> i32;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("icuuc.dll", CallingConvention = CallingConvention.Cdecl)]
public static extern int uloc_getLocaleForLCID(uint hostID, [MarshalAs(UnmanagedType.LPStr)] string locale, int localeCapacity, ref int status);
"@
$api = Add-Type -MemberDefinition $sig -Name 'icuuc_uloc_getLocaleForLCID' -Namespace Win32 -PassThru
# $api::uloc_getLocaleForLCID(hostID, locale, localeCapacity, status)

#uselib "icuuc.dll"
#func global uloc_getLocaleForLCID "uloc_getLocaleForLCID" sptr, sptr, sptr, sptr
; uloc_getLocaleForLCID hostID, locale, localeCapacity, status   ; 戻り値は stat
; hostID : DWORD -> "sptr"
; locale : LPSTR -> "sptr"
; localeCapacity : INT -> "sptr"
; status : UErrorCode* in/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 "icuuc.dll"
#cfunc global uloc_getLocaleForLCID "uloc_getLocaleForLCID" int, str, int, int
; res = uloc_getLocaleForLCID(hostID, locale, localeCapacity, status)
; hostID : DWORD -> "int"
; locale : LPSTR -> "str"
; localeCapacity : INT -> "int"
; status : UErrorCode* in/out -> "int"

; INT uloc_getLocaleForLCID(DWORD hostID, LPSTR locale, INT localeCapacity, UErrorCode* status)
#uselib "icuuc.dll"
#cfunc global uloc_getLocaleForLCID "uloc_getLocaleForLCID" int, str, int, int
; res = uloc_getLocaleForLCID(hostID, locale, localeCapacity, status)
; hostID : DWORD -> "int"
; locale : LPSTR -> "str"
; localeCapacity : INT -> "int"
; status : UErrorCode* in/out -> "int"

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

var (
	icuuc = windows.NewLazySystemDLL("icuuc.dll")
	proculoc_getLocaleForLCID = icuuc.NewProc("uloc_getLocaleForLCID")
)

// hostID (DWORD), locale (LPSTR), localeCapacity (INT), status (UErrorCode* in/out)
r1, _, err := proculoc_getLocaleForLCID.Call(
	uintptr(hostID),
	uintptr(unsafe.Pointer(windows.BytePtrFromString(locale))),
	uintptr(localeCapacity),
	uintptr(status),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // INT

function uloc_getLocaleForLCID(
  hostID: DWORD;   // DWORD
  locale: PAnsiChar;   // LPSTR
  localeCapacity: Integer;   // INT
  status: Pointer   // UErrorCode* in/out
): Integer; cdecl;
  external 'icuuc.dll' name 'uloc_getLocaleForLCID';

result := DllCall("icuuc\uloc_getLocaleForLCID"
    , "UInt", hostID   ; DWORD
    , "AStr", locale   ; LPSTR
    , "Int", localeCapacity   ; INT
    , "Ptr", status   ; UErrorCode* in/out
    , "Cdecl Int")   ; return: INT

●uloc_getLocaleForLCID(hostID, locale, localeCapacity, status) = DLL("icuuc.dll", "int uloc_getLocaleForLCID(dword, char*, int, void*)")
# 呼び出し: uloc_getLocaleForLCID(hostID, locale, localeCapacity, status)
# hostID : DWORD -> "dword"
# locale : LPSTR -> "char*"
# localeCapacity : INT -> "int"
# status : UErrorCode* in/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)。
# ※cdecl関数。DLL()宣言はstdcall前提。cdeclは EXEC_PTR(`cdecl`,…) を使用。