Vista Tutorial - Is there a race condition reading the log?

# Return all events that have occured since a particular one ($start)
# If $start is negative, begin that many records from the current end
of log.
function read_log ([int]$start)
$log = new-object system.diagnostics.eventlog("MyCustApp")
if ($start -lt 0) {$start = $log.entries.count +
$log.entries[0].Index + $start}
if ($start -lt $log.entries[0].Index){$start =
$log.entries[0].Index}
$start = $start - $log.entries[0].Index - 1
while (++$start -lt $log.entries.count) {
$log.entries.item($start) }
}

If the $start message number is far enough back in the log it might
take a while to process all the messages. During that time it's
likely that new messages will be added. When I first created the log
and started reading it I didn't look at $log.entries[0].Index. Then
all hell broke loose when the log got big enough for messages to roll
off the back and $start no longer started in the right place. It
essentially skipped loads of records.

$start - $log.entries[0].Index takes care of that problem.

But now I'm worried about what will happen if a job that reads the log
happens to be reading when messages roll off. Imperically, it seems
as though a bunch of messages will be skipped because the event index
numbers will shift during processing.

Any thoughts or experience with this?