RegisterWindowMessageA

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

DWORD RegisterWindowMessageA(
    LPCSTR lpString
);

<DllImport("USER32.dll", CharSet:=CharSet.Ansi, SetLastError:=True, ExactSpelling:=True)>
Public Shared Function RegisterWindowMessageA(
    <MarshalAs(UnmanagedType.LPStr)> lpString As String   ' LPCSTR
) As UInteger
End Function

' lpString : LPCSTR
Declare PtrSafe Function RegisterWindowMessageA Lib "user32" ( _
    ByVal lpString As String) As Long
' VBA7前提(PtrSafe)。32bit Office では LongPtr→Long。Integer=16bit / Long=32bit / LongLong=64bit。

import ctypes
from ctypes import wintypes

RegisterWindowMessageA = ctypes.windll.user32.RegisterWindowMessageA
RegisterWindowMessageA.restype = wintypes.DWORD
RegisterWindowMessageA.argtypes = [
    wintypes.LPCSTR,  # lpString : LPCSTR
]
# GetLastError: use ctypes.GetLastError() (or ctypes.WinDLL(use_last_error=True))

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('USER32.dll')
RegisterWindowMessageA = Fiddle::Function.new(
  lib['RegisterWindowMessageA'],
  [
    Fiddle::TYPE_VOIDP,  # lpString : LPCSTR
  ],
  -Fiddle::TYPE_INT)

#[link(name = "user32")]
extern "system" {
    fn RegisterWindowMessageA(
        lpString: *const u8  // LPCSTR
    ) -> u32;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("USER32.dll", CharSet = CharSet.Ansi, SetLastError = true)]
public static extern uint RegisterWindowMessageA([MarshalAs(UnmanagedType.LPStr)] string lpString);
"@
$api = Add-Type -MemberDefinition $sig -Name 'USER32_RegisterWindowMessageA' -Namespace Win32 -PassThru
# $api::RegisterWindowMessageA(lpString)

#uselib "USER32.dll"
#func global RegisterWindowMessageA "RegisterWindowMessageA" sptr
; RegisterWindowMessageA lpString   ; 戻り値は stat
; lpString : LPCSTR -> "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 RegisterWindowMessageA "RegisterWindowMessageA" str
; res = RegisterWindowMessageA(lpString)
; lpString : LPCSTR -> "str"

; DWORD RegisterWindowMessageA(LPCSTR lpString)
#uselib "USER32.dll"
#cfunc global RegisterWindowMessageA "RegisterWindowMessageA" str
; res = RegisterWindowMessageA(lpString)
; lpString : LPCSTR -> "str"

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

var (
	user32 = windows.NewLazySystemDLL("USER32.dll")
	procRegisterWindowMessageA = user32.NewProc("RegisterWindowMessageA")
)

// lpString (LPCSTR)
r1, _, err := procRegisterWindowMessageA.Call(
	uintptr(unsafe.Pointer(windows.BytePtrFromString(lpString))),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // DWORD

function RegisterWindowMessageA(
  lpString: PAnsiChar   // LPCSTR
): DWORD; stdcall;
  external 'USER32.dll' name 'RegisterWindowMessageA';

result := DllCall("USER32\RegisterWindowMessageA"
    , "AStr", lpString   ; LPCSTR
    , "UInt")   ; return: DWORD

●RegisterWindowMessageA(lpString) = DLL("USER32.dll", "dword RegisterWindowMessageA(char*)")
# 呼び出し: RegisterWindowMessageA(lpString)
# lpString : LPCSTR -> "char*"
# 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)。