SnmpOidToStr

// wsnmp32.dll
#include <windows.h>

DWORD SnmpOidToStr(
    smiOID* srcOID,
    DWORD size,
    LPSTR string
);

<DllImport("wsnmp32.dll", ExactSpelling:=True)>
Public Shared Function SnmpOidToStr(
    srcOID As IntPtr,   ' smiOID*
    size As UInteger,   ' DWORD
    <MarshalAs(UnmanagedType.LPStr)> [string] As System.Text.StringBuilder   ' LPSTR out
) As UInteger
End Function

' srcOID : smiOID*
' size : DWORD
' string : LPSTR out
Declare PtrSafe Function SnmpOidToStr Lib "wsnmp32" ( _
    ByVal srcOID As LongPtr, _
    ByVal size As Long, _
    ByVal string 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

SnmpOidToStr = ctypes.windll.wsnmp32.SnmpOidToStr
SnmpOidToStr.restype = wintypes.DWORD
SnmpOidToStr.argtypes = [
    ctypes.c_void_p,  # srcOID : smiOID*
    wintypes.DWORD,  # size : DWORD
    wintypes.LPSTR,  # string : LPSTR out
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('wsnmp32.dll')
SnmpOidToStr = Fiddle::Function.new(
  lib['SnmpOidToStr'],
  [
    Fiddle::TYPE_VOIDP,  # srcOID : smiOID*
    -Fiddle::TYPE_INT,  # size : DWORD
    Fiddle::TYPE_VOIDP,  # string : LPSTR out
  ],
  -Fiddle::TYPE_INT)

#[link(name = "wsnmp32")]
extern "system" {
    fn SnmpOidToStr(
        srcOID: *mut smiOID,  // smiOID*
        size: u32,  // DWORD
        string: *mut u8  // LPSTR out
    ) -> u32;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("wsnmp32.dll")]
public static extern uint SnmpOidToStr(IntPtr srcOID, uint size, [MarshalAs(UnmanagedType.LPStr)] System.Text.StringBuilder string);
"@
$api = Add-Type -MemberDefinition $sig -Name 'wsnmp32_SnmpOidToStr' -Namespace Win32 -PassThru
# $api::SnmpOidToStr(srcOID, size, string)

#uselib "wsnmp32.dll"
#func global SnmpOidToStr "SnmpOidToStr" sptr, sptr, sptr
; SnmpOidToStr varptr(srcOID), size, varptr(string)   ; 戻り値は stat
; srcOID : smiOID* -> "sptr"
; size : DWORD -> "sptr"
; string : LPSTR 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 "wsnmp32.dll"
#cfunc global SnmpOidToStr "SnmpOidToStr" var, int, var
; res = SnmpOidToStr(srcOID, size, string)
; srcOID : smiOID* -> "var"
; size : DWORD -> "int"
; string : LPSTR out -> "var"
; ※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。

; DWORD SnmpOidToStr(smiOID* srcOID, DWORD size, LPSTR string)
#uselib "wsnmp32.dll"
#cfunc global SnmpOidToStr "SnmpOidToStr" var, int, var
; res = SnmpOidToStr(srcOID, size, string)
; srcOID : smiOID* -> "var"
; size : DWORD -> "int"
; string : LPSTR out -> "var"
; ※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 (
	wsnmp32 = windows.NewLazySystemDLL("wsnmp32.dll")
	procSnmpOidToStr = wsnmp32.NewProc("SnmpOidToStr")
)

// srcOID (smiOID*), size (DWORD), string (LPSTR out)
r1, _, err := procSnmpOidToStr.Call(
	uintptr(srcOID),
	uintptr(size),
	uintptr(string),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // DWORD

function SnmpOidToStr(
  srcOID: Pointer;   // smiOID*
  size: DWORD;   // DWORD
  string: PAnsiChar   // LPSTR out
): DWORD; stdcall;
  external 'wsnmp32.dll' name 'SnmpOidToStr';

result := DllCall("wsnmp32\SnmpOidToStr"
    , "Ptr", srcOID   ; smiOID*
    , "UInt", size   ; DWORD
    , "Ptr", string   ; LPSTR out
    , "UInt")   ; return: DWORD

●SnmpOidToStr(srcOID, size, string) = DLL("wsnmp32.dll", "dword SnmpOidToStr(void*, dword, char*)")
# 呼び出し: SnmpOidToStr(srcOID, size, string)
# srcOID : smiOID* -> "void*"
# size : DWORD -> "dword"
# string : LPSTR out -> "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)。