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FindFirstVolumeW

関数

システム上の最初のボリュームを列挙し検索を開始する。

DLLKERNEL32.dll文字セットUnicode (-W)呼出規約winapiSetLastErrorあり対応OSWindows XP 以降

シグネチャ

// KERNEL32.dll  (Unicode / -W)
#include <windows.h>

HANDLE FindFirstVolumeW(
    LPWSTR lpszVolumeName,
    DWORD cchBufferLength
);

パラメーター

名前	型	方向
lpszVolumeName	LPWSTR	out
cchBufferLength	DWORD	in

戻り値の型: HANDLE

各言語での呼び出し定義

// KERNEL32.dll  (Unicode / -W)
#include <windows.h>

HANDLE FindFirstVolumeW(
    LPWSTR lpszVolumeName,
    DWORD cchBufferLength
);

[DllImport("KERNEL32.dll", CharSet = CharSet.Unicode, SetLastError = true, ExactSpelling = true)]
static extern IntPtr FindFirstVolumeW(
    [MarshalAs(UnmanagedType.LPWStr)] System.Text.StringBuilder lpszVolumeName,   // LPWSTR out
    uint cchBufferLength   // DWORD
);

<DllImport("KERNEL32.dll", CharSet:=CharSet.Unicode, SetLastError:=True, ExactSpelling:=True)>
Public Shared Function FindFirstVolumeW(
    <MarshalAs(UnmanagedType.LPWStr)> lpszVolumeName As System.Text.StringBuilder,   ' LPWSTR out
    cchBufferLength As UInteger   ' DWORD
) As IntPtr
End Function

' lpszVolumeName : LPWSTR out
' cchBufferLength : DWORD
Declare PtrSafe Function FindFirstVolumeW Lib "kernel32" ( _
    ByVal lpszVolumeName As LongPtr, _
    ByVal cchBufferLength As Long) As LongPtr
' Unicode(W): 文字列は ByVal As LongPtr とし StrPtr(unicodeStr) を渡す
' VBA7前提(PtrSafe)。32bit Office では LongPtr→Long。Integer=16bit / Long=32bit / LongLong=64bit。

import ctypes
from ctypes import wintypes

FindFirstVolumeW = ctypes.windll.kernel32.FindFirstVolumeW
FindFirstVolumeW.restype = ctypes.c_void_p
FindFirstVolumeW.argtypes = [
    wintypes.LPWSTR,  # lpszVolumeName : LPWSTR out
    wintypes.DWORD,  # cchBufferLength : DWORD
]
# GetLastError: use ctypes.GetLastError() (or ctypes.WinDLL(use_last_error=True))

require 'fiddle'
require 'fiddle/import'

lib = Fiddle.dlopen('KERNEL32.dll')
FindFirstVolumeW = Fiddle::Function.new(
  lib['FindFirstVolumeW'],
  [
    Fiddle::TYPE_VOIDP,  # lpszVolumeName : LPWSTR out
    -Fiddle::TYPE_INT,  # cchBufferLength : DWORD
  ],
  Fiddle::TYPE_VOIDP)
# Wide strings: pass str.encode("UTF-16LE") + "\x00\x00"

#[link(name = "kernel32")]
extern "system" {
    fn FindFirstVolumeW(
        lpszVolumeName: *mut u16,  // LPWSTR out
        cchBufferLength: u32  // DWORD
    ) -> *mut core::ffi::c_void;
}
// crates: windows-sys provides ready-made bindings for this API.

$sig = @"
[DllImport("KERNEL32.dll", CharSet = CharSet.Unicode, SetLastError = true)]
public static extern IntPtr FindFirstVolumeW([MarshalAs(UnmanagedType.LPWStr)] System.Text.StringBuilder lpszVolumeName, uint cchBufferLength);
"@
$api = Add-Type -MemberDefinition $sig -Name 'KERNEL32_FindFirstVolumeW' -Namespace Win32 -PassThru
# $api::FindFirstVolumeW(lpszVolumeName, cchBufferLength)

#uselib "KERNEL32.dll"
#func global FindFirstVolumeW "FindFirstVolumeW" wptr, wptr
; FindFirstVolumeW varptr(lpszVolumeName), cchBufferLength   ; 戻り値は stat
; lpszVolumeName : LPWSTR out -> "wptr"
; cchBufferLength : DWORD -> "wptr"
; ※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 "KERNEL32.dll"
#cfunc global FindFirstVolumeW "FindFirstVolumeW" var, int
; res = FindFirstVolumeW(lpszVolumeName, cchBufferLength)
; lpszVolumeName : LPWSTR out -> "var"
; cchBufferLength : DWORD -> "int"
; ※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。#uselib "KERNEL32.dll"
#cfunc global FindFirstVolumeW "FindFirstVolumeW" sptr, int
; res = FindFirstVolumeW(varptr(lpszVolumeName), cchBufferLength)
; lpszVolumeName : LPWSTR out -> "sptr"
; cchBufferLength : DWORD -> "int"
; ※出力/バッファ引数はポインタ方式(token=sptr / 呼び出しは varptr(変数))。

出力引数:

; HANDLE FindFirstVolumeW(LPWSTR lpszVolumeName, DWORD cchBufferLength)
#uselib "KERNEL32.dll"
#cfunc global FindFirstVolumeW "FindFirstVolumeW" var, int
; res = FindFirstVolumeW(lpszVolumeName, cchBufferLength)
; lpszVolumeName : LPWSTR out -> "var"
; cchBufferLength : DWORD -> "int"
; ※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。; HANDLE FindFirstVolumeW(LPWSTR lpszVolumeName, DWORD cchBufferLength)
#uselib "KERNEL32.dll"
#cfunc global FindFirstVolumeW "FindFirstVolumeW" intptr, int
; res = FindFirstVolumeW(varptr(lpszVolumeName), cchBufferLength)
; lpszVolumeName : LPWSTR out -> "intptr"
; cchBufferLength : DWORD -> "int"
; ※出力/バッファ引数はポインタ方式(token=intptr / 呼び出しは varptr(変数))。

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

var (
	kernel32 = windows.NewLazySystemDLL("KERNEL32.dll")
	procFindFirstVolumeW = kernel32.NewProc("FindFirstVolumeW")
)

// lpszVolumeName (LPWSTR out), cchBufferLength (DWORD)
r1, _, err := procFindFirstVolumeW.Call(
	uintptr(lpszVolumeName),
	uintptr(cchBufferLength),
)
_ = err  // syscall.Errno (valid when the call sets last-error)
_ = r1   // HANDLE

function FindFirstVolumeW(
  lpszVolumeName: PWideChar;   // LPWSTR out
  cchBufferLength: DWORD   // DWORD
): THandle; stdcall;
  external 'KERNEL32.dll' name 'FindFirstVolumeW';

result := DllCall("KERNEL32\FindFirstVolumeW"
    , "Ptr", lpszVolumeName   ; LPWSTR out
    , "UInt", cchBufferLength   ; DWORD
    , "Ptr")   ; return: HANDLE

●FindFirstVolumeW(lpszVolumeName, cchBufferLength) = DLL("KERNEL32.dll", "void* FindFirstVolumeW(char*, dword)")
# 呼び出し: FindFirstVolumeW(lpszVolumeName, cchBufferLength)
# lpszVolumeName : LPWSTR out -> "char*"
# cchBufferLength : DWORD -> "dword"
# 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)。
# ※-W(Unicode)関数。なでしこ1はANSIのため -A 版の利用を推奨。