UnregisterClassA

// USER32.dll  (ANSI / -A)
#include <windows.h>

BOOL UnregisterClassA(
    LPCSTR lpClassName,
    HINSTANCE hInstance   // optional
);

<DllImport("USER32.dll", CharSet:=CharSet.Ansi, SetLastError:=True, ExactSpelling:=True)>
Public Shared Function UnregisterClassA(
    <MarshalAs(UnmanagedType.LPStr)> lpClassName As String,   ' LPCSTR
    hInstance As IntPtr   ' HINSTANCE optional
) As <MarshalAs(UnmanagedType.Bool)> Boolean
End Function

' lpClassName : LPCSTR
' hInstance : HINSTANCE optional
Declare PtrSafe Function UnregisterClassA Lib "user32" ( _
    ByVal lpClassName As String, _
    ByVal hInstance 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

UnregisterClassA = ctypes.windll.user32.UnregisterClassA
UnregisterClassA.restype = wintypes.BOOL
UnregisterClassA.argtypes = [
    wintypes.LPCSTR,  # lpClassName : LPCSTR
    wintypes.HANDLE,  # hInstance : HINSTANCE optional
]
# GetLastError: use ctypes.GetLastError() (or ctypes.WinDLL(use_last_error=True))

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('USER32.dll')
UnregisterClassA = Fiddle::Function.new(
  lib['UnregisterClassA'],
  [
    Fiddle::TYPE_VOIDP,  # lpClassName : LPCSTR
    Fiddle::TYPE_VOIDP,  # hInstance : HINSTANCE optional
  ],
  Fiddle::TYPE_INT)

#[link(name = "user32")]
extern "system" {
    fn UnregisterClassA(
        lpClassName: *const u8,  // LPCSTR
        hInstance: *mut core::ffi::c_void  // HINSTANCE optional
    ) -> i32;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[return: MarshalAs(UnmanagedType.Bool)]
[DllImport("USER32.dll", CharSet = CharSet.Ansi, SetLastError = true)]
public static extern bool UnregisterClassA([MarshalAs(UnmanagedType.LPStr)] string lpClassName, IntPtr hInstance);
"@
$api = Add-Type -MemberDefinition $sig -Name 'USER32_UnregisterClassA' -Namespace Win32 -PassThru
# $api::UnregisterClassA(lpClassName, hInstance)

#uselib "USER32.dll"
#func global UnregisterClassA "UnregisterClassA" sptr, sptr
; UnregisterClassA lpClassName, hInstance   ; 戻り値は stat
; lpClassName : LPCSTR -> "sptr"
; hInstance : HINSTANCE optional -> "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 "USER32.dll"
#cfunc global UnregisterClassA "UnregisterClassA" str, sptr
; res = UnregisterClassA(lpClassName, hInstance)
; lpClassName : LPCSTR -> "str"
; hInstance : HINSTANCE optional -> "sptr"

; BOOL UnregisterClassA(LPCSTR lpClassName, HINSTANCE hInstance)
#uselib "USER32.dll"
#cfunc global UnregisterClassA "UnregisterClassA" str, intptr
; res = UnregisterClassA(lpClassName, hInstance)
; lpClassName : LPCSTR -> "str"
; hInstance : HINSTANCE optional -> "intptr"

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

var (
	user32 = windows.NewLazySystemDLL("USER32.dll")
	procUnregisterClassA = user32.NewProc("UnregisterClassA")
)

// lpClassName (LPCSTR), hInstance (HINSTANCE optional)
r1, _, err := procUnregisterClassA.Call(
	uintptr(unsafe.Pointer(windows.BytePtrFromString(lpClassName))),
	uintptr(hInstance),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // BOOL

function UnregisterClassA(
  lpClassName: PAnsiChar;   // LPCSTR
  hInstance: THandle   // HINSTANCE optional
): BOOL; stdcall;
  external 'USER32.dll' name 'UnregisterClassA';

result := DllCall("USER32\UnregisterClassA"
    , "AStr", lpClassName   ; LPCSTR
    , "Ptr", hInstance   ; HINSTANCE optional
    , "Int")   ; return: BOOL

●UnregisterClassA(lpClassName, hInstance) = DLL("USER32.dll", "bool UnregisterClassA(char*, void*)")
# 呼び出し: UnregisterClassA(lpClassName, hInstance)
# lpClassName : LPCSTR -> "char*"
# hInstance : HINSTANCE optional -> "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)。

const std = @import("std");

extern "user32" fn UnregisterClassA(
    lpClassName: [*c]const u8, // LPCSTR
    hInstance: ?*anyopaque // HINSTANCE optional
) callconv(std.os.windows.WINAPI) i32;

proc UnregisterClassA(
    lpClassName: cstring,  # LPCSTR
    hInstance: pointer  # HINSTANCE optional
): int32 {.importc: "UnregisterClassA", stdcall, dynlib: "USER32.dll".}

pragma(lib, "user32");
extern(Windows)
int UnregisterClassA(
    const(char)* lpClassName,   // LPCSTR
    void* hInstance   // HINSTANCE optional
);

ccall((:UnregisterClassA, "USER32.dll"), stdcall, Int32,
      (Cstring, Ptr{Cvoid}),
      lpClassName, hInstance)
# lpClassName : LPCSTR -> Cstring
# hInstance : HINSTANCE optional -> Ptr{Cvoid}
# stdcall は 32bit のみ意味を持つ(x64 では無視)。

local ffi = require("ffi")
ffi.cdef[[
int32_t UnregisterClassA(
    const char* lpClassName,
    void* hInstance);
]]
local user32 = ffi.load("user32")
-- user32.UnregisterClassA(lpClassName, hInstance)
-- lpClassName : LPCSTR
-- hInstance : HINSTANCE optional
-- 構造体/GUIDへのポインタは cdef が通るよう void* で表記(実型は各引数コメント参照)。値渡し構造体・enum は対応する typedef を cdef に追加すること。

const koffi = require('koffi');
const lib = koffi.load('USER32.dll');
const UnregisterClassA = lib.func('__stdcall', 'UnregisterClassA', 'int32_t', ['str', 'void *']);
// UnregisterClassA(lpClassName, hInstance)
// lpClassName : LPCSTR -> 'str'
// hInstance : HINSTANCE optional -> 'void *'
// 出力ポインタは koffi.out(...) で包む。構造体は koffi.struct で定義。

const lib = Deno.dlopen("USER32.dll", {
  UnregisterClassA: { parameters: ["buffer", "pointer"], result: "i32" },
});
// lib.symbols.UnregisterClassA(lpClassName, hInstance)
// lpClassName : LPCSTR -> "buffer"
// hInstance : HINSTANCE optional -> "pointer"
// 文字列は "buffer"。ANSI(-A) は new TextEncoder() で UTF-8/ANSI バイト列(末尾に \x00)を渡す。
// 値渡し構造体は { struct: [ ...field types... ] } を使用。

<?php
$ffi = FFI::cdef(<<<C
int32_t UnregisterClassA(
    const char* lpClassName,
    void* hInstance);
C, "USER32.dll");
// $ffi->UnregisterClassA(lpClassName, hInstance);
// lpClassName : LPCSTR
// hInstance : HINSTANCE optional
// 構造体/GUIDへのポインタは cdef が通るよう void* で表記(実型は各引数コメント参照)。値渡し構造体・enum は対応する typedef を cdef に追加すること。
// WINAPI(stdcall): x64 では呼出規約が統一されるため問題なし。x86 では __stdcall 対応のラッパが必要な場合あり。

import com.sun.jna.*;
import com.sun.jna.ptr.*;
import com.sun.jna.win32.StdCallLibrary;
import com.sun.jna.win32.W32APIOptions;

public interface User32 extends StdCallLibrary {
    User32 INSTANCE = Native.load("user32", User32.class, W32APIOptions.ASCII_OPTIONS);
    boolean UnregisterClassA(
        String lpClassName,   // LPCSTR
        Pointer hInstance   // HINSTANCE optional
    );
}

@[Link("user32")]
lib LibUSER32
  fun UnregisterClassA = UnregisterClassA(
    lpClassName : UInt8*,   # LPCSTR
    hInstance : Void*   # HINSTANCE optional
  ) : Int32
end
# 構造体/GUID/enum は lib 内に対応する型定義が必要。
# 呼出規約: x64 は規約統一のため OK。x86(32bit)は WINAPI=stdcall だが Crystal の fun に stdcall 付与構文がなく非対応。

import 'dart:ffi';
import 'package:ffi/ffi.dart';

typedef UnregisterClassANative = Int32 Function(Pointer<Utf8>, Pointer<Void>);
typedef UnregisterClassADart = int Function(Pointer<Utf8>, Pointer<Void>);
final UnregisterClassA = DynamicLibrary.open('USER32.dll')
    .lookupFunction<UnregisterClassANative, UnregisterClassADart>('UnregisterClassA');
// lpClassName : LPCSTR -> Pointer<Utf8>
// hInstance : HINSTANCE optional -> Pointer<Void>
// 文字列は package:ffi の "...".toNativeUtf16()/toNativeUtf8() で変換。

{$mode objfpc}{$H+}
function UnregisterClassA(
  lpClassName: PAnsiChar;   // LPCSTR
  hInstance: THandle   // HINSTANCE optional
): BOOL; stdcall;
  external 'USER32.dll' name 'UnregisterClassA';

import Foreign
import Foreign.C.Types
import Foreign.C.String

foreign import stdcall safe "UnregisterClassA"
  c_UnregisterClassA :: CString -> Ptr () -> IO CInt
-- lpClassName : LPCSTR -> CString
-- hInstance : HINSTANCE optional -> Ptr ()
-- 要 GHC(Windows)。stdcall は x64 では ccall として扱われる。ブロックする API は safe 呼び出し推奨。

open Ctypes
open Foreign

let unregisterclassa =
  foreign "UnregisterClassA"
    (string @-> (ptr void) @-> returning int32_t)
(* lpClassName : LPCSTR -> string *)
(* hInstance : HINSTANCE optional -> (ptr void) *)
(* foreign は cdecl 前提。x64 Windows では WINAPI と一致。構造体は ctypes structure を定義のこと。 *)

(cffi:define-foreign-library user32 (t "USER32.dll"))
(cffi:use-foreign-library user32)

(cffi:defcfun ("UnregisterClassA" unregister-class-a :convention :stdcall) :int32
  (lp-class-name :string)   ; LPCSTR
  (h-instance :pointer))   ; HINSTANCE optional
; isize/usize(INT_PTR/SIZE_T)は x64 前提で :int64/:uint64。x86 では :int32/:uint32。

use Win32::API;
my $UnregisterClassA = Win32::API::More->new('USER32',
    'BOOL UnregisterClassA(LPCSTR lpClassName, HANDLE hInstance)');
# my $ret = $UnregisterClassA->Call($lpClassName, $hInstance);
# lpClassName : LPCSTR -> LPCSTR
# hInstance : HINSTANCE optional -> HANDLE
# 値渡し構造体は pack() した文字列、または Win32::API::Struct を使用。