quick way to check that my local file system has NOT changed

[israel Gold]

Hi,
I use rsync to synchronize my file system with remote server.
Rsync is time consuming and I want to avoid it in many cases.
I am looking for a quick way to check that my local file system has NOT
changed
since a given time, so that I would not have to run rsync.
The trivial solution would be to scan the modification time of all
files.
Is there a faster trick ?
--
Israel Gold, WiGo Technologies, rhglaw1 at barak.net.il
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