[PD] comport port numbers :: bash trick

[Hans-Christoph Steiner]

On Sep 24, 2006, at 6:52 PM, Martin Peach wrote:

> Hans-Christoph Steiner wrote:
>>
>> On Sep 24, 2006, at 5:49 PM, Martin Peach wrote:
>>
>>> Martin Peach wrote:
>>>> Martin Peach wrote:
>>>>> Hans-Christoph Steiner wrote:
>>>>>>
>>>>>> On the latest version of [comport], the [info( message should  
>>>>>> print out a similar output to the Pd window.
>>>>> Don't try it on Windows though, you'll crash pd.
>>>>>    for(i=1; i<COMPORT_MAX; i++)
>>>>>    {
>>>>>        /* TODO: this should actually probe ports */
>>>>>        post("\t%d - COM%s", i, i);
>>>>>    }
>>>>> doesn't work as well as being useless and irritating (it is  
>>>>> supposed to just print 98 lines of COM names).
>>>>> But since i isn't a string, post() crashes.
>>>>> I'm looking into how to enumerate serial ports on Windows  
>>>>> properly.
>>>>> It looks like you have to open each device to find out about  
>>>>> it, unlike on linux where they are listed as files.
>>>>>
>>>> So I changed it in cvs. Now you get a list of available serial  
>>>> ports in Windows as well. At least it works for me but I only  
>>>> have one port here so I don't know if it _really_ works.
>>>>
>>>
>>> Now I'm trying it on linux where I have only two ports and I get  
>>> the full list of 32 devices. Maybe we should try probing them all  
>>> to see which ones actually exist?
>>
>> Nice work on the COM stuff, sorry for introducing a bug on  
>> Windows. :-/  I'll be getting a WinXP autobuild machine up in the  
>> next couple days, so that will help.
>>
>> That would be nice.  On Mac OS X, the exist if they are in the  
>> file system.  On newer Linux-based systems, that is also the  
>> case.  But the only manually created files are still prevalent.
>>
> They 'exist' virtually but there is not usually a real device to  
> plug your cable into except for the first one or two entries. It  
> seems like you have to open each virtual device and see if you get  
> a valid handle. If you do then the hardware exists (and you have to  
> close it again), otherwise you have to check the error code to see  
> if it wasn't opened because it's already in use or because it isn't  
> there.
>
> Martin

I guess I meant that and vice versa: on Mac OS X, if they are in the  
filesystem, they exist.  I think its the same with Linux udev systems.

I am wary of opening and closing every port to test if its there  
unless its absolutely necessary.  I don't know about Windows or GNU/ 
Linux, but some devices take a long time to open, so the whole system  
hangs waiting for it.  The Apple modem is an example of that.

I suppose that the testing phase could be in a background thread,  
then it wouldn't hang.  A simple thread that just iterated thru all  
possible ports, testing to see what exists, then making a report to  
the console and the status outlet when complete.

.hc


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