VOID
RtlCopyString(
IN OUT PSTRING DestinationString,
IN PSTRING SourceString /* optional */
);
RtlCopyString copies a source string to a destination string.
The DestinationString Length is set to zero if no source string is supplied, but this does not affect the length of the DestinationString buffer. The MaximumLength and Buffer members of the DestinationString are not modified by this routine.
The number of bytes copied from the SourceString is either the length of SourceString or the maximum length of DestinationString, whichever is smaller.
The DestinationString and SourceString buffers must be resident if the caller is running at IRQL >= DISPATCH_LEVEL.