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PdhEnumMachinesA

関数
データソース内のマシン名一覧を列挙する(ANSI版)。
DLLpdh.dll文字セットANSI (-A)呼出規約winapi対応OSWindows XP 以降
📘 Microsoft Learn (日本語) · English

シグネチャ

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

DWORD PdhEnumMachinesA(
    LPCSTR szDataSource,   // optional
    LPSTR mszMachineList,   // optional
    DWORD* pcchBufferSize
);

パラメーター

名前型方向説明
szDataSourceLPCSTRinoptional列挙元のログファイルパス(ANSI)。NULLでリアルタイムデータを使う。
mszMachineListLPSTRoutoptionalコンピューター名のNULL区切りリストを受け取るバッファ(ANSI)。NULLでサイズ取得。
pcchBufferSizeDWORD*inoutバッファの文字数を入出力するポインタ。

戻り値の型: DWORD

各言語での呼び出し定義

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

DWORD PdhEnumMachinesA(
    LPCSTR szDataSource,   // optional
    LPSTR mszMachineList,   // optional
    DWORD* pcchBufferSize
);
[DllImport("pdh.dll", CharSet = CharSet.Ansi, ExactSpelling = true)]
static extern uint PdhEnumMachinesA(
    [MarshalAs(UnmanagedType.LPStr)] string szDataSource,   // LPCSTR optional
    [MarshalAs(UnmanagedType.LPStr)] System.Text.StringBuilder mszMachineList,   // LPSTR optional, out
    ref uint pcchBufferSize   // DWORD* in/out
);
<DllImport("pdh.dll", CharSet:=CharSet.Ansi, ExactSpelling:=True)>
Public Shared Function PdhEnumMachinesA(
    <MarshalAs(UnmanagedType.LPStr)> szDataSource As String,   ' LPCSTR optional
    <MarshalAs(UnmanagedType.LPStr)> mszMachineList As System.Text.StringBuilder,   ' LPSTR optional, out
    ByRef pcchBufferSize As UInteger   ' DWORD* in/out
) As UInteger
End Function
' szDataSource : LPCSTR optional
' mszMachineList : LPSTR optional, out
' pcchBufferSize : DWORD* in/out
Declare PtrSafe Function PdhEnumMachinesA Lib "pdh" ( _
    ByVal szDataSource As String, _
    ByVal mszMachineList As String, _
    ByRef pcchBufferSize 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

PdhEnumMachinesA = ctypes.windll.pdh.PdhEnumMachinesA
PdhEnumMachinesA.restype = wintypes.DWORD
PdhEnumMachinesA.argtypes = [
    wintypes.LPCSTR,  # szDataSource : LPCSTR optional
    wintypes.LPSTR,  # mszMachineList : LPSTR optional, out
    ctypes.POINTER(wintypes.DWORD),  # pcchBufferSize : DWORD* in/out
]
require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('pdh.dll')
PdhEnumMachinesA = Fiddle::Function.new(
  lib['PdhEnumMachinesA'],
  [
    Fiddle::TYPE_VOIDP,  # szDataSource : LPCSTR optional
    Fiddle::TYPE_VOIDP,  # mszMachineList : LPSTR optional, out
    Fiddle::TYPE_VOIDP,  # pcchBufferSize : DWORD* in/out
  ],
  -Fiddle::TYPE_INT)
#[link(name = "pdh")]
extern "system" {
    fn PdhEnumMachinesA(
        szDataSource: *const u8,  // LPCSTR optional
        mszMachineList: *mut u8,  // LPSTR optional, out
        pcchBufferSize: *mut u32  // DWORD* in/out
    ) -> u32;
}
// crates: windows-sys provides ready-made bindings for this API.
$sig = @"
[DllImport("pdh.dll", CharSet = CharSet.Ansi)]
public static extern uint PdhEnumMachinesA([MarshalAs(UnmanagedType.LPStr)] string szDataSource, [MarshalAs(UnmanagedType.LPStr)] System.Text.StringBuilder mszMachineList, ref uint pcchBufferSize);
"@
$api = Add-Type -MemberDefinition $sig -Name 'pdh_PdhEnumMachinesA' -Namespace Win32 -PassThru
# $api::PdhEnumMachinesA(szDataSource, mszMachineList, pcchBufferSize)
#uselib "pdh.dll"
#func global PdhEnumMachinesA "PdhEnumMachinesA" sptr, sptr, sptr
; PdhEnumMachinesA szDataSource, varptr(mszMachineList), varptr(pcchBufferSize)   ; 戻り値は stat
; szDataSource : LPCSTR optional -> "sptr"
; mszMachineList : LPSTR optional, out -> "sptr"
; pcchBufferSize : DWORD* 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。
出力引数: 
#uselib "pdh.dll"
#cfunc global PdhEnumMachinesA "PdhEnumMachinesA" str, var, var
; res = PdhEnumMachinesA(szDataSource, mszMachineList, pcchBufferSize)
; szDataSource : LPCSTR optional -> "str"
; mszMachineList : LPSTR optional, out -> "var"
; pcchBufferSize : DWORD* 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。
出力引数: 
; DWORD PdhEnumMachinesA(LPCSTR szDataSource, LPSTR mszMachineList, DWORD* pcchBufferSize)
#uselib "pdh.dll"
#cfunc global PdhEnumMachinesA "PdhEnumMachinesA" str, var, var
; res = PdhEnumMachinesA(szDataSource, mszMachineList, pcchBufferSize)
; szDataSource : LPCSTR optional -> "str"
; mszMachineList : LPSTR optional, out -> "var"
; pcchBufferSize : DWORD* 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 (
	pdh = windows.NewLazySystemDLL("pdh.dll")
	procPdhEnumMachinesA = pdh.NewProc("PdhEnumMachinesA")
)

// szDataSource (LPCSTR optional), mszMachineList (LPSTR optional, out), pcchBufferSize (DWORD* in/out)
r1, _, err := procPdhEnumMachinesA.Call(
	uintptr(unsafe.Pointer(windows.BytePtrFromString(szDataSource))),
	uintptr(mszMachineList),
	uintptr(pcchBufferSize),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // DWORD
function PdhEnumMachinesA(
  szDataSource: PAnsiChar;   // LPCSTR optional
  mszMachineList: PAnsiChar;   // LPSTR optional, out
  pcchBufferSize: Pointer   // DWORD* in/out
): DWORD; stdcall;
  external 'pdh.dll' name 'PdhEnumMachinesA';
result := DllCall("pdh\PdhEnumMachinesA"
    , "AStr", szDataSource   ; LPCSTR optional
    , "Ptr", mszMachineList   ; LPSTR optional, out
    , "Ptr", pcchBufferSize   ; DWORD* in/out
    , "UInt")   ; return: DWORD
●PdhEnumMachinesA(szDataSource, mszMachineList, pcchBufferSize) = DLL("pdh.dll", "dword PdhEnumMachinesA(char*, char*, void*)")
# 呼び出し: PdhEnumMachinesA(szDataSource, mszMachineList, pcchBufferSize)
# szDataSource : LPCSTR optional -> "char*"
# mszMachineList : LPSTR optional, out -> "char*"
# pcchBufferSize : DWORD* 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)。