RtlAllocateAndInitializeSidEx - NtDoc

#ifndef _NTRTL_H
#if (PHNT_VERSION >= PHNT_WINBLUE)

_Must_inspect_result_
NTSYSAPI
NTSTATUS
NTAPI
RtlAllocateAndInitializeSidEx(
    _In_ PSID_IDENTIFIER_AUTHORITY IdentifierAuthority,
    _In_ UCHAR SubAuthorityCount,
    _In_reads_(SubAuthorityCount) PULONG SubAuthorities,
    _Outptr_ PSID *Sid
    );

#endif
#endif
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