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Date: Mon, 17 Jan 2011 16:27:53 -0800
From: Donna Rigas <donna.rigas@gmail.com>
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To: linux-kernel@vger.kernel.org
Subject: serial port programming question (newbie)
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I see lots of serial port programming examples where the
port settings are saved before being changed to the desired settings,
then restored to the original before exiting the program via
tcgetattr and tgsetattr. 

I see one example where someone comments that this is not necessary.

Can someone tell me whether or not it is necessary to save and restore the
old settings and if so, why?