Timeouts when reading from a serial port

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3 total messages Started by Steven T. Abell Mon, 03 Aug 1992 18:18

#424

Author: Steven T. Abell
Date: Mon, 03 Aug 1992 18:18

9 lines
797 bytes

The read function blocks until it has read enough stuff from the port.
But if there is nothing out there to respond, the application hangs.
Very annoying. I've dealt with this kind of thing a zillion times on
embedded realtime systems, but I don't know how to approach it in this
programming environment. Is there a preferred way of solving this problem?

Thanks,

Steve abell@netcom.com

Re: Timeouts when reading from a serial port

#430

Author: Sean T. Lamont
Date: Tue, 04 Aug 1992 05:36

12 lines
1116 bytes

In article <71tmbc#.abell@netcom.com> abell@netcom.com (Steven T. Abell) writes:
>The read function blocks until it has read enough stuff from the port.
>But if there is nothing out there to respond, the application hangs.

Look at select();


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Sean T. Lamont, Abstract Software        |   "Don't oppress me, It's
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----------------"My employers opinions are my own, not yours."-----------------

Re: Timeouts when reading from a serial port

#451

Author: moose
Date: Tue, 04 Aug 1992 16:30

19 lines
1221 bytes

In article <71tmbc#.abell@netcom.com> abell@netcom.com (Steven T. Abell)  
writes:
> The read function blocks until it has read enough stuff from the port.
> But if there is nothing out there to respond, the application hangs.
> Very annoying. I've dealt with this kind of thing a zillion times on
> embedded realtime systems, but I don't know how to approach it in this
> programming environment. Is there a preferred way of solving this problem?
> 

There is an ioctl called FIONBIO which will handle this problem for you.  The  
only documentation is in the header file /usr/include/sys/ioctl.h, but this one  
is pretty straight forward.

 
--
Michael Rutman			|	moose@svcdudes.com
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Software Ventures		|	maker of MicroPhone II
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