tcgetattr problem

Wed Sep 27 22:36:00 GMT 2006

On 2006年9月27日, ahnkle wrote:
> hi
>> I wrote a small program to test some serial stuff. I was puzzled because
> I recall that I was able to set baud rate on a serial port before, but
> now I cannot.
>> I call tcgetattr() after I open the serial port, but it fails (the
> tcsetattr() also fails which first got my attention).
>> I enclose a short example, and cygwin details, too. Any ideas?

Hmm... Either you've asked this before, or I saw an almost exactly the
same program posted within the past month or two. Quoting the first few
lines of your program:
#define PORT "com1"
...
 fd = open(PORT, O_RDWR | O_NOCTTY );
There's your problem. When you open a port as "com1", it looks like a
file to Cygwin, since it doesn't recognize it as a valid device name.
Thus any attempt to manipulate that fd as a device will fail.
Use the Cygwin device (e.g., "/dev/ttyS0").
HTH,
	Igor
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