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Date: Sat, 12 Jun 2010 11:31:04 +0200
From: Gilles Chanteperdrix <gilles.chanteperdrix@xenomai.org>
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Subject: Re: [Xenomai-help] error on rt_dev_read, code Success,
 what does it mean?
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To: Everett Wang <everteq@domain.hid>
Cc: xenomai@xenomai.org

Everett Wang wrote:
> Hi,
> 
> I am developing a real time programming using xenomai, RTDM. When
> I try to read serial port, I sometimes get this message:
> 
> error on rt_dev_read, code Success
> 
> I checked my program and found that when rt_dev_read returns a
> negative number, this message is printed. What does this error message
> mean? It seems that my port is open when I tried to read from it.

It means that you are probably using errno, and since rt_dev_read does
not set errno, you get "Success" as error message instead of the real
error message. If you want to print the real error message, you should
use strerror(-rc) where rc is the return code of rt_dev_read.

But of course, I am just guessing here, seeing your test code would help
more.


-- 
					    Gilles.