TcGetFlowNameA

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

DWORD TcGetFlowNameA(
    HANDLE FlowHandle,
    DWORD StrSize,
    LPSTR pFlowName
);

<DllImport("TRAFFIC.dll", CharSet:=CharSet.Ansi, ExactSpelling:=True)>
Public Shared Function TcGetFlowNameA(
    FlowHandle As IntPtr,   ' HANDLE
    StrSize As UInteger,   ' DWORD
    <MarshalAs(UnmanagedType.LPStr)> pFlowName As System.Text.StringBuilder   ' LPSTR out
) As UInteger
End Function

' FlowHandle : HANDLE
' StrSize : DWORD
' pFlowName : LPSTR out
Declare PtrSafe Function TcGetFlowNameA Lib "traffic" ( _
    ByVal FlowHandle As LongPtr, _
    ByVal StrSize As Long, _
    ByVal pFlowName 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

TcGetFlowNameA = ctypes.windll.traffic.TcGetFlowNameA
TcGetFlowNameA.restype = wintypes.DWORD
TcGetFlowNameA.argtypes = [
    wintypes.HANDLE,  # FlowHandle : HANDLE
    wintypes.DWORD,  # StrSize : DWORD
    wintypes.LPSTR,  # pFlowName : LPSTR out
]

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('TRAFFIC.dll')
TcGetFlowNameA = Fiddle::Function.new(
  lib['TcGetFlowNameA'],
  [
    Fiddle::TYPE_VOIDP,  # FlowHandle : HANDLE
    -Fiddle::TYPE_INT,  # StrSize : DWORD
    Fiddle::TYPE_VOIDP,  # pFlowName : LPSTR out
  ],
  -Fiddle::TYPE_INT)

#[link(name = "traffic")]
extern "system" {
    fn TcGetFlowNameA(
        FlowHandle: *mut core::ffi::c_void,  // HANDLE
        StrSize: u32,  // DWORD
        pFlowName: *mut u8  // LPSTR out
    ) -> u32;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("TRAFFIC.dll", CharSet = CharSet.Ansi)]
public static extern uint TcGetFlowNameA(IntPtr FlowHandle, uint StrSize, [MarshalAs(UnmanagedType.LPStr)] System.Text.StringBuilder pFlowName);
"@
$api = Add-Type -MemberDefinition $sig -Name 'TRAFFIC_TcGetFlowNameA' -Namespace Win32 -PassThru
# $api::TcGetFlowNameA(FlowHandle, StrSize, pFlowName)

#uselib "TRAFFIC.dll"
#func global TcGetFlowNameA "TcGetFlowNameA" sptr, sptr, sptr
; TcGetFlowNameA FlowHandle, StrSize, varptr(pFlowName)   ; 戻り値は stat
; FlowHandle : HANDLE -> "sptr"
; StrSize : DWORD -> "sptr"
; pFlowName : 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 "TRAFFIC.dll"
#cfunc global TcGetFlowNameA "TcGetFlowNameA" sptr, int, var
; res = TcGetFlowNameA(FlowHandle, StrSize, pFlowName)
; FlowHandle : HANDLE -> "sptr"
; StrSize : DWORD -> "int"
; pFlowName : 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 TcGetFlowNameA(HANDLE FlowHandle, DWORD StrSize, LPSTR pFlowName)
#uselib "TRAFFIC.dll"
#cfunc global TcGetFlowNameA "TcGetFlowNameA" intptr, int, var
; res = TcGetFlowNameA(FlowHandle, StrSize, pFlowName)
; FlowHandle : HANDLE -> "intptr"
; StrSize : DWORD -> "int"
; pFlowName : 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 (
	traffic = windows.NewLazySystemDLL("TRAFFIC.dll")
	procTcGetFlowNameA = traffic.NewProc("TcGetFlowNameA")
)

// FlowHandle (HANDLE), StrSize (DWORD), pFlowName (LPSTR out)
r1, _, err := procTcGetFlowNameA.Call(
	uintptr(FlowHandle),
	uintptr(StrSize),
	uintptr(pFlowName),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // DWORD

function TcGetFlowNameA(
  FlowHandle: THandle;   // HANDLE
  StrSize: DWORD;   // DWORD
  pFlowName: PAnsiChar   // LPSTR out
): DWORD; stdcall;
  external 'TRAFFIC.dll' name 'TcGetFlowNameA';

result := DllCall("TRAFFIC\TcGetFlowNameA"
    , "Ptr", FlowHandle   ; HANDLE
    , "UInt", StrSize   ; DWORD
    , "Ptr", pFlowName   ; LPSTR out
    , "UInt")   ; return: DWORD

●TcGetFlowNameA(FlowHandle, StrSize, pFlowName) = DLL("TRAFFIC.dll", "dword TcGetFlowNameA(void*, dword, char*)")
# 呼び出し: TcGetFlowNameA(FlowHandle, StrSize, pFlowName)
# FlowHandle : HANDLE -> "void*"
# StrSize : DWORD -> "dword"
# pFlowName : 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)。