RtlFindUnicodeSubstring - NtDoc

#ifndef _NTRTL_H
#if (PHNT_VERSION >= PHNT_THRESHOLD)

_Must_inspect_result_
NTSYSAPI
PWCHAR
NTAPI
RtlFindUnicodeSubstring(
    _In_ PUNICODE_STRING FullString,
    _In_ PUNICODE_STRING SearchString,
    _In_ BOOLEAN CaseInSensitive
    );

#endif
#endif
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