[PD] preventing comport freezes

[Hans-Christoph Steiner]

On May 8, 2009, at 8:14 AM, Martin Peach wrote:

> Hans-Christoph Steiner wrote:
>> So right now, when [comport] is open and that device gets  
>> disconnected, comport freezes and Pd crashes.  My guess is that  
>> comport is waiting and therefore blocking.  It seems like the  
>> select() call should prevent that, any other guesses on how to  
>> prevent comport from locking like this?  Many arduino users would  
>> be very happy.
>
> Is this on linux? It should be non-blocking on Windows.
> I suppose it crashes only when you try to send something, not if you  
> just pull the cable out. I would have thought that if hardware  
> handshaking was off, the port will send anyway. I seem to remember  
> sending into an oscilloscope probe with no cable present.
> Select is problematic, as we have seen with recent [tcpserver],  
> checking if each byte can be sent before it goes out slows the whole  
> thing down a lot.

This is on Mac OS X mostly, but maybe linux too.  It seems odd that  
select() would slow things down so much.  Perhaps there is some kind  
of flag that can lighten the load.

This stuff is definitely a pain.

.hc

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