NetNews Usenet Archive 1992 #19/NN_1992_19.iso/spool/comp/lang/tcl/1278

Internet Message Format | 1992-08-31 | 1.1 KB

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From: [e-mail] (Van Kelly)
Newsgroups: comp.lang.tcl
Subject: Periodic Actions in Tcl/Tk
Message-ID: <[e-mail]>
Date: 31 Aug 92 15:56:50 GMT
Sender: [e-mail]
Organization: AT&T Bell Laboratories, Murray Hill, NJ, USA
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What is the best way to define a period action (say, once every n seconds)
in a Tcl/TclX/Tk environment, given that there may be a number of these
one might wish to set up and later selectively cancel at a later date.

The first thing I thought of was to have a global variable, say FOO,
containing the code for a periodic action followed by an after command
to re-evaluate itself.  But this is obviously tail-recursive and may
explode its stack pretty fast.  If one could define a bunch of
pseudo-clocks as normal X-events to which one could bind actions, that would
clearly be a better approch, but there's no obvious way to do this in Tcl(X).

Any advice?  Email responses and followup posts are both satisfactory.

Van Kelly
[e-mail]