RtlUpperChar - NtDoc

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

/**
 * The RtlUpperChar routine converts the specified character to uppercase.
 *
 * \param Character The character to convert.
 * \return The uppercase equivalent of the specified character.
 * \sa https://learn.microsoft.com/en-us/windows-hardware/drivers/ddi/ntddk/nf-ntddk-rtlupperchar
 */
NTSYSAPI
CHAR
NTAPI
RtlUpperChar(
    _In_ CHAR Character
    );

#endif

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// ntddk.h

NTSYSAPI CHAR RtlUpperChar(
  [in] CHAR Character
);
View the official Windows Driver Kit DDI reference

NtDoc

This function is documented in Windows Driver Kit.

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Windows Driver Kit DDI reference (nf-ntddk-rtlupperchar)

RtlUpperChar function

Description

The RtlUpperChar routine converts the specified character to uppercase.

Parameters

Character [in]

Specifies the character to convert.

Return value

RtlUpperChar returns the uppercase version of the specified character or returns the value specified by the caller for Character if the specified character cannot be converted.

Remarks

RtlUpperChar returns the input Character unconverted if it is the lead byte of a multibyte character or if the uppercase equivalent of Character is a double-byte character. To convert such characters, use RtlUpcaseUnicodeChar.

RtlUpperChar is not recommended because the function is designed to work for ASCII range A-Z letters. Instead, use RtlUpcaseUnicodeChar.

See also

RtlUpcaseUnicodeChar

RtlUpperString

View the official Windows Driver Kit DDI reference

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