RtlDowncaseUnicodeChar - NtDoc

#ifndef _NTRTL_H

/**
 * The RtlDowncaseUnicodeChar routine converts the specified Unicode character to lowercase.
 *
 * \param[in] SourceCharacter Specifies the character to convert.
 * \return The lowercase version of the specified Unicode character.
 * \sa https://learn.microsoft.com/en-us/windows-hardware/drivers/ddi/wdm/nf-wdm-rtldowncaseunicodechar
 */
NTSYSAPI
WCHAR
NTAPI
RtlDowncaseUnicodeChar(
    _In_ WCHAR SourceCharacter
    );

#endif
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