ioctl() support

Kern Sibbald
Mon Nov 20 01:06:00 GMT 2000


I'm running CYGWIN 1.1.2 (my Xlib didn't work with 1.1.4; will
soon try 1.1.5), and am very happy with it. I have built a
version of apcupsd (UPS daemon) that works great on Win32
except for "dumb" UPSes which require serial line control
with ioctl() TIOCMBIS, TIOCMBIC, and TIOCMGET.  My ioctl()
calls always return with "Invalid argument".  

In a quick look at the CYGWIN source, it appears that you do
Is this true or am I missing something?

If you do not support them, do you have any plans to support

Assuming that you do not support them, is there any way after
I do an open() on the serial port that I can get the Windows
serial port handle so that I can interface directly to the
port with GetCommModemStatus() and EscapeCommFunction()
without having to rewrite all the open()/close() code 
that you have already so nicely done?

Thanks for the great product.

Best regards,


Want to unsubscribe from this list?
Send a message to

More information about the Cygwin mailing list