You can use the
watch command for that.
In the default setting it executes the trailing command every 2 seconds. The time can be specified with
To use it to monitor your filesystem you may either use
ls -1 (if you want to see only one directory) or
find (if you also want to watch subdirectories) as the command.
To check for changes in /tmp and all of its subdirectories in (near)real time execute
watch -n 0.1 find /tmp. An interval of 0.1 seconds is the fastest,
watch can go and should be sufficient for any human. And I assume you are human, aren't you?