As you said you are using Tk, why not give "after" a try. It allows you to sepcify ms, so 0.5 second is not a problem. For document, go "Tk", then "after".

my Re: setting up non-gui callbacks in Perl/Tk provides one example of using "after". It appears as "repeat", which is just a different face of "after".

In reply to Re: IP Packet count at regular intervals of time by pg
in thread IP Packet count at regular intervals of time by prakashrj

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