WIn32API レジストリキーを列挙する RegEnumKeyEx

レジストリキーを列挙するには、RegEnumKeyEx関数を用いる。

LONG RegEnumKeyEx(
  HKEY hKey,                  // 列挙するべきキーのハンドル
  DWORD dwIndex,              // サブキーのインデックス番号
  LPTSTR lpName,              // サブキー名が格納されるバッファ
  LPDWORD lpcName,            // サブキー名バッファのサイズ
  LPDWORD lpReserved,         // 予約済み
  LPTSTR lpClass,             // クラス名が格納されるバッファ
  LPDWORD lpcClass,           // クラス文字列バッファのサイズ
  PFILETIME lpftLastWriteTime // 最終書き込み時刻
);

HKEY_LOCAL_MACHINEのサブキーを列挙するサンプルプログラム

HKEY_LOCAL_MACHINE直下のレジストリキーのキー名と最終書き込み時刻を表示している

#include <windows.h>
#include <stdio.h>

int main()
{
    TCHAR szSubkeyName[MAX_PATH];
    DWORD dwSubkeyNameSize;
    FILETIME ftLastWriteTime;
    
    for (DWORD dwIndex = 0; TRUE; dwIndex++) {
        
        DWORD dwResult;

        dwSubkeyNameSize = sizeof(szSubkeyName)/sizeof(szSubkeyName[0]);

        dwResult = RegEnumKeyEx(HKEY_LOCAL_MACHINE, 
                            dwIndex, 
                            szSubkeyName, 
                            &dwSubkeyNameSize, 
                            NULL, 
                            NULL, 
                            NULL, 
                            &ftLastWriteTime);
    
        if (dwResult == ERROR_SUCCESS) {

            FILETIME ftLocalTime;
            SYSTEMTIME LastWriteTime;
            TCHAR szLastWriteTime[32];
            
            ::FileTimeToLocalFileTime(&ftLastWriteTime, &ftLocalTime);
            ::FileTimeToSystemTime(&ftLocalTime, &LastWriteTime);

            _sntprintf(szLastWriteTime, 
                sizeof(szLastWriteTime)/sizeof(szLastWriteTime[0]),
                TEXT("%04d/%02d/%02d %02d:%02d:%02d"), 
                LastWriteTime.wYear, LastWriteTime.wMonth, LastWriteTime.wDay, 
                LastWriteTime.wHour, LastWriteTime.wMinute, LastWriteTime.wSecond);

            _tprintf(TEXT("SubkeyName: %s, LastWriteTime: %s\n"), szSubkeyName, szLastWriteTime);

        } else if (dwResult == ERROR_NO_MORE_ITEMS) {//列挙し終わるとRegEnumKeyExはERROR_NO_MORE_ITEMSを返す
            puts("ERROR_NO_MORE_ITEMS");
            break;
        } else {
            puts("RegEnumKeyEx error");
            break;
        }
 
    }
    
    return 0;
}

実行結果

SubkeyName: BCD00000000, LastWriteTime: 2012/03/05 03:04:22
SubkeyName: HARDWARE, LastWriteTime: 2012/03/05 03:04:16
SubkeyName: SAM, LastWriteTime: 2012/03/05 03:04:26
SubkeyName: SECURITY, LastWriteTime: 2012/03/05 03:04:25
SubkeyName: SOFTWARE, LastWriteTime: 2012/03/05 03:04:22
SubkeyName: SYSTEM, LastWriteTime: 2012/03/05 03:04:16
ERROR_NO_MORE_ITEMS

次のように、RegOpenKeyExで、HKEY_LOCAL_MACHINEのキーをオープンしてもよい

#include <windows.h>
#include <stdio.h>

int main()
{
    TCHAR szSubkeyName[MAX_PATH];
    DWORD dwSubkeyNameSize;
    FILETIME ftLastWriteTime;
    HKEY hKey;
    LONG lRet;

    lRet = RegOpenKeyEx(HKEY_LOCAL_MACHINE, NULL, 0, KEY_ENUMERATE_SUB_KEYS, &hKey);
    if (lRet != ERROR_SUCCESS) {
        return 1;
    }
    
    for (DWORD dwIndex = 0; TRUE; dwIndex++) {
        
        DWORD dwResult;

        dwSubkeyNameSize = sizeof(szSubkeyName)/sizeof(szSubkeyName[0]);

        dwResult = RegEnumKeyEx(hKey, 
                            dwIndex, 
                            szSubkeyName, 
                            &dwSubkeyNameSize, 
                            NULL, 
                            NULL, 
                            NULL, 
                            &ftLastWriteTime);
    
        if (dwResult == ERROR_SUCCESS) {

            FILETIME ftLocalTime;
            SYSTEMTIME LastWriteTime;
            TCHAR szLastWriteTime[32];
            
            ::FileTimeToLocalFileTime(&ftLastWriteTime, &ftLocalTime);
            ::FileTimeToSystemTime(&ftLocalTime, &LastWriteTime);

            _sntprintf(szLastWriteTime, 
                sizeof(szLastWriteTime)/sizeof(szLastWriteTime[0]),
                TEXT("%04d/%02d/%02d %02d:%02d:%02d"), 
                LastWriteTime.wYear, LastWriteTime.wMonth, LastWriteTime.wDay, 
                LastWriteTime.wHour, LastWriteTime.wMinute, LastWriteTime.wSecond);

            _tprintf(TEXT("SubkeyName: %s, LastWriteTime: %s\n"), szSubkeyName, szLastWriteTime);

        } else if (dwResult == ERROR_NO_MORE_ITEMS) {//列挙し終わるとRegEnumKeyExはERROR_NO_MORE_ITEMSを返す
            puts("ERROR_NO_MORE_ITEMS");
            break;
        } else {
            puts("RegEnumKeyEx error");
            break;
        }
 
    }
    
    RegCloseKey(hKey);
    
    return 0;
}

次は、HKEY_LOCAL_MACHINEのサブキーである「SOFTWARE」のサブキーを列挙する例。RegOpenKeyExの第２引数に、サブキー名を指定する。

#include <windows.h>
#include <stdio.h>

int main()
{
    TCHAR szSubkeyName[MAX_PATH];
    DWORD dwSubkeyNameSize;
    FILETIME ftLastWriteTime;
    HKEY hKey;
    LONG lRet;

    lRet = RegOpenKeyEx(HKEY_LOCAL_MACHINE, TEXT("SOFTWARE"), 0, KEY_ENUMERATE_SUB_KEYS, &hKey);
    if (lRet != ERROR_SUCCESS) {
        return 1;
    }
    
    for (DWORD dwIndex = 0; TRUE; dwIndex++) {
        
        DWORD dwResult;

        dwSubkeyNameSize = sizeof(szSubkeyName)/sizeof(szSubkeyName[0]);

        dwResult = RegEnumKeyEx(hKey, 
                            dwIndex, 
                            szSubkeyName, 
                            &dwSubkeyNameSize, 
                            NULL, 
                            NULL, 
                            NULL, 
                            &ftLastWriteTime);
    
        if (dwResult == ERROR_SUCCESS) {

            FILETIME ftLocalTime;
            SYSTEMTIME LastWriteTime;
            TCHAR szLastWriteTime[32];
            
            ::FileTimeToLocalFileTime(&ftLastWriteTime, &ftLocalTime);
            ::FileTimeToSystemTime(&ftLocalTime, &LastWriteTime);

            _sntprintf(szLastWriteTime, 
                sizeof(szLastWriteTime)/sizeof(szLastWriteTime[0]),
                TEXT("%04d/%02d/%02d %02d:%02d:%02d"), 
                LastWriteTime.wYear, LastWriteTime.wMonth, LastWriteTime.wDay, 
                LastWriteTime.wHour, LastWriteTime.wMinute, LastWriteTime.wSecond);

            _tprintf(TEXT("SubkeyName: %s, LastWriteTime: %s\n"), szSubkeyName, szLastWriteTime);

        } else if (dwResult == ERROR_NO_MORE_ITEMS) {//列挙し終わるとRegEnumKeyExはERROR_NO_MORE_ITEMSを返す
            puts("ERROR_NO_MORE_ITEMS");
            break;
        } else {
            puts("RegEnumKeyEx error");
            break;
        }
 
    }
    
    RegCloseKey(hKey);
    
    return 0;
}

実行結果（HKEY_LOCAL_MACHINE\SOFTWAREのサブキーを列挙）

SubkeyName: ABBYY, LastWriteTime: 2011/10/29 15:31:40
SubkeyName: Adobe, LastWriteTime: 2012/01/21 15:57:53
SubkeyName: Apple Computer, Inc., LastWriteTime: 2012/01/16 00:24:33
SubkeyName: Apple Inc., LastWriteTime: 2012/01/16 00:24:33
SubkeyName: AuthenTec, LastWriteTime: 2011/10/19 02:52:09
SubkeyName: calibre, LastWriteTime: 2011/12/11 12:11:00
SubkeyName: CyberLink, LastWriteTime: 2011/10/19 03:19:14
SubkeyName: Google, LastWriteTime: 2011/10/29 13:46:15
SubkeyName: Hewlett-Packard, LastWriteTime: 2011/11/12 10:36:34
SubkeyName: ICE, LastWriteTime: 2011/11/12 10:35:56
SubkeyName: IDT, LastWriteTime: 2011/10/19 03:19:14
SubkeyName: Intel, LastWriteTime: 2011/10/19 02:51:40
SubkeyName: JavaSoft, LastWriteTime: 2012/03/31 00:07:46
SubkeyName: JreMetrics, LastWriteTime: 2012/03/31 00:07:46
SubkeyName: Lake, LastWriteTime: 2011/10/19 03:19:14
SubkeyName: Licenses, LastWriteTime: 2012/03/31 15:08:27
SubkeyName: Macromedia, LastWriteTime: 2011/10/19 02:46:31
SubkeyName: Macrovision, LastWriteTime: 2011/12/03 19:41:14
SubkeyName: MAXSOFT-OCRON, LastWriteTime: 2011/10/29 15:46:11
SubkeyName: Microsoft, LastWriteTime: 2012/03/31 15:08:15
SubkeyName: Microsoft Corporation, LastWriteTime: 2012/03/18 13:48:18

・・・・・（さらに列挙は続く）

参考
http://msdn.microsoft.com/ja-jp/library/cc429912.aspx