SnmpDecodeMsg

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

DWORD SnmpDecodeMsg(
    INT_PTR session,
    INT_PTR* srcEntity,
    INT_PTR* dstEntity,
    INT_PTR* context,
    INT_PTR* pdu,
    smiOCTETS* msgBufDesc
);

<DllImport("wsnmp32.dll", ExactSpelling:=True)>
Public Shared Function SnmpDecodeMsg(
    session As IntPtr,   ' INT_PTR
    ByRef srcEntity As IntPtr,   ' INT_PTR* in/out
    ByRef dstEntity As IntPtr,   ' INT_PTR* in/out
    ByRef context As IntPtr,   ' INT_PTR* in/out
    ByRef pdu As IntPtr,   ' INT_PTR* in/out
    msgBufDesc As IntPtr   ' smiOCTETS* in/out
) As UInteger
End Function

' session : INT_PTR
' srcEntity : INT_PTR* in/out
' dstEntity : INT_PTR* in/out
' context : INT_PTR* in/out
' pdu : INT_PTR* in/out
' msgBufDesc : smiOCTETS* in/out
Declare PtrSafe Function SnmpDecodeMsg Lib "wsnmp32" ( _
    ByVal session As LongPtr, _
    ByRef srcEntity As LongPtr, _
    ByRef dstEntity As LongPtr, _
    ByRef context As LongPtr, _
    ByRef pdu As LongPtr, _
    ByVal msgBufDesc 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

SnmpDecodeMsg = ctypes.windll.wsnmp32.SnmpDecodeMsg
SnmpDecodeMsg.restype = wintypes.DWORD
SnmpDecodeMsg.argtypes = [
    ctypes.c_ssize_t,  # session : INT_PTR
    ctypes.POINTER(ctypes.c_ssize_t),  # srcEntity : INT_PTR* in/out
    ctypes.POINTER(ctypes.c_ssize_t),  # dstEntity : INT_PTR* in/out
    ctypes.POINTER(ctypes.c_ssize_t),  # context : INT_PTR* in/out
    ctypes.POINTER(ctypes.c_ssize_t),  # pdu : INT_PTR* in/out
    ctypes.c_void_p,  # msgBufDesc : smiOCTETS* in/out
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('wsnmp32.dll')
SnmpDecodeMsg = Fiddle::Function.new(
  lib['SnmpDecodeMsg'],
  [
    Fiddle::TYPE_INTPTR_T,  # session : INT_PTR
    Fiddle::TYPE_VOIDP,  # srcEntity : INT_PTR* in/out
    Fiddle::TYPE_VOIDP,  # dstEntity : INT_PTR* in/out
    Fiddle::TYPE_VOIDP,  # context : INT_PTR* in/out
    Fiddle::TYPE_VOIDP,  # pdu : INT_PTR* in/out
    Fiddle::TYPE_VOIDP,  # msgBufDesc : smiOCTETS* in/out
  ],
  -Fiddle::TYPE_INT)

#[link(name = "wsnmp32")]
extern "system" {
    fn SnmpDecodeMsg(
        session: isize,  // INT_PTR
        srcEntity: *mut isize,  // INT_PTR* in/out
        dstEntity: *mut isize,  // INT_PTR* in/out
        context: *mut isize,  // INT_PTR* in/out
        pdu: *mut isize,  // INT_PTR* in/out
        msgBufDesc: *mut smiOCTETS  // smiOCTETS* in/out
    ) -> u32;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("wsnmp32.dll")]
public static extern uint SnmpDecodeMsg(IntPtr session, ref IntPtr srcEntity, ref IntPtr dstEntity, ref IntPtr context, ref IntPtr pdu, IntPtr msgBufDesc);
"@
$api = Add-Type -MemberDefinition $sig -Name 'wsnmp32_SnmpDecodeMsg' -Namespace Win32 -PassThru
# $api::SnmpDecodeMsg(session, srcEntity, dstEntity, context, pdu, msgBufDesc)

#uselib "wsnmp32.dll"
#func global SnmpDecodeMsg "SnmpDecodeMsg" sptr, sptr, sptr, sptr, sptr, sptr
; SnmpDecodeMsg session, varptr(srcEntity), varptr(dstEntity), varptr(context), varptr(pdu), varptr(msgBufDesc)   ; 戻り値は stat
; session : INT_PTR -> "sptr"
; srcEntity : INT_PTR* in/out -> "sptr"
; dstEntity : INT_PTR* in/out -> "sptr"
; context : INT_PTR* in/out -> "sptr"
; pdu : INT_PTR* in/out -> "sptr"
; msgBufDesc : smiOCTETS* 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 "wsnmp32.dll"
#cfunc global SnmpDecodeMsg "SnmpDecodeMsg" sptr, var, var, var, var, var
; res = SnmpDecodeMsg(session, srcEntity, dstEntity, context, pdu, msgBufDesc)
; session : INT_PTR -> "sptr"
; srcEntity : INT_PTR* in/out -> "var"
; dstEntity : INT_PTR* in/out -> "var"
; context : INT_PTR* in/out -> "var"
; pdu : INT_PTR* in/out -> "var"
; msgBufDesc : smiOCTETS* in/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 SnmpDecodeMsg(INT_PTR session, INT_PTR* srcEntity, INT_PTR* dstEntity, INT_PTR* context, INT_PTR* pdu, smiOCTETS* msgBufDesc)
#uselib "wsnmp32.dll"
#cfunc global SnmpDecodeMsg "SnmpDecodeMsg" intptr, var, var, var, var, var
; res = SnmpDecodeMsg(session, srcEntity, dstEntity, context, pdu, msgBufDesc)
; session : INT_PTR -> "intptr"
; srcEntity : INT_PTR* in/out -> "var"
; dstEntity : INT_PTR* in/out -> "var"
; context : INT_PTR* in/out -> "var"
; pdu : INT_PTR* in/out -> "var"
; msgBufDesc : smiOCTETS* in/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")
	procSnmpDecodeMsg = wsnmp32.NewProc("SnmpDecodeMsg")
)

// session (INT_PTR), srcEntity (INT_PTR* in/out), dstEntity (INT_PTR* in/out), context (INT_PTR* in/out), pdu (INT_PTR* in/out), msgBufDesc (smiOCTETS* in/out)
r1, _, err := procSnmpDecodeMsg.Call(
	uintptr(session),
	uintptr(srcEntity),
	uintptr(dstEntity),
	uintptr(context),
	uintptr(pdu),
	uintptr(msgBufDesc),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // DWORD

function SnmpDecodeMsg(
  session: NativeInt;   // INT_PTR
  srcEntity: Pointer;   // INT_PTR* in/out
  dstEntity: Pointer;   // INT_PTR* in/out
  context: Pointer;   // INT_PTR* in/out
  pdu: Pointer;   // INT_PTR* in/out
  msgBufDesc: Pointer   // smiOCTETS* in/out
): DWORD; stdcall;
  external 'wsnmp32.dll' name 'SnmpDecodeMsg';

result := DllCall("wsnmp32\SnmpDecodeMsg"
    , "Ptr", session   ; INT_PTR
    , "Ptr", srcEntity   ; INT_PTR* in/out
    , "Ptr", dstEntity   ; INT_PTR* in/out
    , "Ptr", context   ; INT_PTR* in/out
    , "Ptr", pdu   ; INT_PTR* in/out
    , "Ptr", msgBufDesc   ; smiOCTETS* in/out
    , "UInt")   ; return: DWORD

●SnmpDecodeMsg(session, srcEntity, dstEntity, context, pdu, msgBufDesc) = DLL("wsnmp32.dll", "dword SnmpDecodeMsg(int, void*, void*, void*, void*, void*)")
# 呼び出し: SnmpDecodeMsg(session, srcEntity, dstEntity, context, pdu, msgBufDesc)
# session : INT_PTR -> "int"
# srcEntity : INT_PTR* in/out -> "void*"
# dstEntity : INT_PTR* in/out -> "void*"
# context : INT_PTR* in/out -> "void*"
# pdu : INT_PTR* in/out -> "void*"
# msgBufDesc : smiOCTETS* 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)。