silencing speakup with echo

[Chuck Hallenbeck]

Recently someone mentioned echoing 7 to the silent variable in speakup:

echo 7 > /sys/accessibility/speakup/silent

It seems to kill speakup on a per-user basis, in such a way that
pressing the print-screen key restores it to normal use.

The speakup user guide names that variable, but contains no other
information about it. What other values besides 7 can I echo to that
variable, and what will they do?  

Thanks,
Chuck

-- 
Chuck in Hudson.
My website is hallenbeck.ftml.net, and my Jabber ID is chuckh1 at jabber.org
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I'm an early riser: I normally wake up about o dark hundred hours.