Wed Sep 27 23:12:00 GMT 2006
On 18:36 Wed 27 Sep , Igor Peshansky wrote:
> #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").
Strangely, com1 *does* work in the call to open. Having tried "/dev/ttyS0",
tcgetattr() works ok.
I also note that read() and write() work ok too using "com1", but
tcsetattr() also fails.
BTW, I obtained the CVS source, but couldn't find the _ioctl() call
anywhere in my (brief) grepping. Is there any documentation about internal
structure, and whats going on under the hood?
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