RtlDowncaseUnicodeChar - NtDoc

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

NTSYSAPI
WCHAR
NTAPI
RtlDowncaseUnicodeChar(
    _In_ WCHAR SourceCharacter
    );

#endif

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This function is documented in Windows Driver Kit.

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