KEY_FULL_INFORMATION - NtDoc

Native API online documentation, based on the System Informer (formerly Process Hacker) phnt headers
#ifndef _NTREGAPI_H

typedef struct _KEY_FULL_INFORMATION
{
    LARGE_INTEGER LastWriteTime;
    ULONG TitleIndex;
    ULONG ClassOffset;
    ULONG ClassLength;
    ULONG SubKeys;
    ULONG MaxNameLength;
    ULONG MaxClassLength;
    ULONG Values;
    ULONG MaxValueNameLength;
    ULONG MaxValueDataLength;
    WCHAR Class[1];
} KEY_FULL_INFORMATION, *PKEY_FULL_INFORMATION;

#endif

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This structure is documented in Windows Driver Kit.