RtlIsNameInExpression - NtDoc

Native API online documentation, based on the System Informer (formerly Process Hacker) phnt headers
#ifndef _NTRTL_H
#if (PHNT_VERSION >= PHNT_WIN7)

// ntifs:FsRtlIsNameInExpression
NTSYSAPI
BOOLEAN
NTAPI
RtlIsNameInExpression(
    _In_ PUNICODE_STRING Expression,
    _In_ PUNICODE_STRING Name,
    _In_ BOOLEAN IgnoreCase,
    _In_opt_ PWCH UpcaseTable
    );

#endif
#endif

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This function is documented in Windows SDK.