RtlUnicodeToMultiByteSize - NtDoc

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

#ifndef _NTRTL_H

NTSYSAPI
NTSTATUS
NTAPI
RtlUnicodeToMultiByteSize(
    _Out_ PULONG BytesInMultiByteString,
    _In_reads_bytes_(BytesInUnicodeString) PCWCH UnicodeString,
    _In_ ULONG BytesInUnicodeString
    );

#endif
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This function is documented in Windows Driver Kit.

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