VOID
RtlInitUnicodeString(
IN OUT PUNICODE_STRING DestinationString,
IN PCWSTR SourceString
);
RtlInitUnicodeString initializes a counted Unicode string.
DestinationString is initialized to point to SourceString. The length and maximum length for DestinationString are initialized to the length of SourceString. If SourceString is NULL, the length is zero.
Callers of RtlInitUnicodeString can be running at IRQL <= DISPATCH_LEVEL if the DestinationString buffer is nonpageable. Usually, callers run at IRQL PASSIVE_LEVEL because most other Rtl..String routines cannot be called at raised IRQL.