u_unescape

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

INT u_unescape(
    LPCSTR src,
    WORD* dest,
    INT destCapacity
);

<DllImport("icuuc.dll", ExactSpelling:=True, CallingConvention:=CallingConvention.Cdecl)>
Public Shared Function u_unescape(
    <MarshalAs(UnmanagedType.LPStr)> src As String,   ' LPCSTR
    ByRef dest As UShort,   ' WORD* in/out
    destCapacity As Integer   ' INT
) As Integer
End Function

' src : LPCSTR
' dest : WORD* in/out
' destCapacity : INT
Declare PtrSafe Function u_unescape Lib "icuuc" ( _
    ByVal src As String, _
    ByRef dest As Integer, _
    ByVal destCapacity 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

u_unescape = ctypes.cdll.icuuc.u_unescape
u_unescape.restype = ctypes.c_int
u_unescape.argtypes = [
    wintypes.LPCSTR,  # src : LPCSTR
    ctypes.POINTER(ctypes.c_ushort),  # dest : WORD* in/out
    ctypes.c_int,  # destCapacity : INT
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('icuuc.dll')
u_unescape = Fiddle::Function.new(
  lib['u_unescape'],
  [
    Fiddle::TYPE_VOIDP,  # src : LPCSTR
    Fiddle::TYPE_VOIDP,  # dest : WORD* in/out
    Fiddle::TYPE_INT,  # destCapacity : INT
  ],
  Fiddle::TYPE_INT, Fiddle::Function::CDECL)

#[link(name = "icuuc")]
extern "C" {
    fn u_unescape(
        src: *const u8,  // LPCSTR
        dest: *mut u16,  // WORD* in/out
        destCapacity: i32  // INT
    ) -> i32;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("icuuc.dll", CallingConvention = CallingConvention.Cdecl)]
public static extern int u_unescape([MarshalAs(UnmanagedType.LPStr)] string src, ref ushort dest, int destCapacity);
"@
$api = Add-Type -MemberDefinition $sig -Name 'icuuc_u_unescape' -Namespace Win32 -PassThru
# $api::u_unescape(src, dest, destCapacity)

#uselib "icuuc.dll"
#func global u_unescape "u_unescape" sptr, sptr, sptr
; u_unescape src, varptr(dest), destCapacity   ; 戻り値は stat
; src : LPCSTR -> "sptr"
; dest : WORD* in/out -> "sptr"
; destCapacity : 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 "icuuc.dll"
#cfunc global u_unescape "u_unescape" str, var, int
; res = u_unescape(src, dest, destCapacity)
; src : LPCSTR -> "str"
; dest : WORD* in/out -> "var"
; destCapacity : 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 u_unescape(LPCSTR src, WORD* dest, INT destCapacity)
#uselib "icuuc.dll"
#cfunc global u_unescape "u_unescape" str, var, int
; res = u_unescape(src, dest, destCapacity)
; src : LPCSTR -> "str"
; dest : WORD* in/out -> "var"
; destCapacity : 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 (
	icuuc = windows.NewLazySystemDLL("icuuc.dll")
	procu_unescape = icuuc.NewProc("u_unescape")
)

// src (LPCSTR), dest (WORD* in/out), destCapacity (INT)
r1, _, err := procu_unescape.Call(
	uintptr(unsafe.Pointer(windows.BytePtrFromString(src))),
	uintptr(dest),
	uintptr(destCapacity),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // INT

function u_unescape(
  src: PAnsiChar;   // LPCSTR
  dest: Pointer;   // WORD* in/out
  destCapacity: Integer   // INT
): Integer; cdecl;
  external 'icuuc.dll' name 'u_unescape';

result := DllCall("icuuc\u_unescape"
    , "AStr", src   ; LPCSTR
    , "Ptr", dest   ; WORD* in/out
    , "Int", destCapacity   ; INT
    , "Cdecl Int")   ; return: INT

●u_unescape(src, dest, destCapacity) = DLL("icuuc.dll", "int u_unescape(char*, void*, int)")
# 呼び出し: u_unescape(src, dest, destCapacity)
# src : LPCSTR -> "char*"
# dest : WORD* in/out -> "void*"
# destCapacity : 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)。
# ※cdecl関数。DLL()宣言はstdcall前提。cdeclは EXEC_PTR(`cdecl`,…) を使用。