RtlULongToUChar - NtDoc

#ifndef _NTINTSAFE_H_INCLUDED_
#if WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_APP | WINAPI_PARTITION_SYSTEM | WINAPI_PARTITION_GAMES)

//
// ULONG -> UCHAR conversion
//
_Must_inspect_result_
__inline
NTSTATUS
RtlULongToUChar(
    _In_ ULONG ulOperand,
    _Out_ _Deref_out_range_(==, ulOperand) UCHAR* pch)
{
    NTSTATUS status;

    if (ulOperand <= 255)
    {
        *pch = (UCHAR)ulOperand;
        status = STATUS_SUCCESS;
    }
    else
    {
        *pch = '\0';
        status = STATUS_INTEGER_OVERFLOW;
    }

    return status;
}

#endif
#endif
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