ucnv_open

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

UConverter* ucnv_open(
    LPCSTR converterName,
    UErrorCode* err
);

<DllImport("icuuc.dll", ExactSpelling:=True, CallingConvention:=CallingConvention.Cdecl)>
Public Shared Function ucnv_open(
    <MarshalAs(UnmanagedType.LPStr)> converterName As String,   ' LPCSTR
    ByRef err As Integer   ' UErrorCode* in/out
) As IntPtr
End Function

' converterName : LPCSTR
' err : UErrorCode* in/out
Declare PtrSafe Function ucnv_open Lib "icuuc" ( _
    ByVal converterName As String, _
    ByRef err As Long) As LongPtr
' VBA7前提(PtrSafe)。32bit Office では LongPtr→Long。Integer=16bit / Long=32bit / LongLong=64bit。

import ctypes
from ctypes import wintypes

ucnv_open = ctypes.cdll.icuuc.ucnv_open
ucnv_open.restype = ctypes.c_void_p
ucnv_open.argtypes = [
    wintypes.LPCSTR,  # converterName : LPCSTR
    ctypes.c_void_p,  # err : UErrorCode* in/out
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('icuuc.dll')
ucnv_open = Fiddle::Function.new(
  lib['ucnv_open'],
  [
    Fiddle::TYPE_VOIDP,  # converterName : LPCSTR
    Fiddle::TYPE_VOIDP,  # err : UErrorCode* in/out
  ],
  Fiddle::TYPE_VOIDP, Fiddle::Function::CDECL)

#[link(name = "icuuc")]
extern "C" {
    fn ucnv_open(
        converterName: *const u8,  // LPCSTR
        err: *mut i32  // UErrorCode* in/out
    ) -> *mut isize;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("icuuc.dll", CallingConvention = CallingConvention.Cdecl)]
public static extern IntPtr ucnv_open([MarshalAs(UnmanagedType.LPStr)] string converterName, ref int err);
"@
$api = Add-Type -MemberDefinition $sig -Name 'icuuc_ucnv_open' -Namespace Win32 -PassThru
# $api::ucnv_open(converterName, err)

#uselib "icuuc.dll"
#func global ucnv_open "ucnv_open" sptr, sptr
; ucnv_open converterName, err   ; 戻り値は stat
; converterName : LPCSTR -> "sptr"
; err : 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 ucnv_open "ucnv_open" str, int
; res = ucnv_open(converterName, err)
; converterName : LPCSTR -> "str"
; err : UErrorCode* in/out -> "int"

; UConverter* ucnv_open(LPCSTR converterName, UErrorCode* err)
#uselib "icuuc.dll"
#cfunc global ucnv_open "ucnv_open" str, int
; res = ucnv_open(converterName, err)
; converterName : LPCSTR -> "str"
; err : UErrorCode* in/out -> "int"

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

var (
	icuuc = windows.NewLazySystemDLL("icuuc.dll")
	procucnv_open = icuuc.NewProc("ucnv_open")
)

// converterName (LPCSTR), err (UErrorCode* in/out)
r1, _, err := procucnv_open.Call(
	uintptr(unsafe.Pointer(windows.BytePtrFromString(converterName))),
	uintptr(err),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // UConverter*

function ucnv_open(
  converterName: PAnsiChar;   // LPCSTR
  err: Pointer   // UErrorCode* in/out
): Pointer; cdecl;
  external 'icuuc.dll' name 'ucnv_open';

result := DllCall("icuuc\ucnv_open"
    , "AStr", converterName   ; LPCSTR
    , "Ptr", err   ; UErrorCode* in/out
    , "Cdecl Ptr")   ; return: UConverter*

●ucnv_open(converterName, err) = DLL("icuuc.dll", "void* ucnv_open(char*, void*)")
# 呼び出し: ucnv_open(converterName, err)
# converterName : LPCSTR -> "char*"
# err : 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。