Re: GNAT.Serial_Communications

[tonyg <tonythegair@gmail.com>]

On Apr 19, 1:09 pm, Ludovic Brenta <ludo...@ludovic-brenta.org> wrote:
> tonyg wrote on comp.lang.ada:
>
>
>
> >> Looking at the gnat sercom package it has a total lack of options for
> >> flow control. I am going to look at posix packages now and its options
> >> with serial interfaces. Does anyone know if Adacore are planning to
> >> add some more functionality to this package?
>
> > Just to let you all know ( I'm sure the world was waiting with baited
> > breath!) that thanks to the help received, its now all working. I'll
> > document what the problem was with some additional stuff to let future
> > people know.
>
> > It was the flow control setting and it can be fixed by opening another
> > terminal window and using the command
>
> > stty --file=/dev/ttyUSB0 -crtscts
>
> > However - any ada program compiled with the gnat serial communications
> > package if run again will reset the port to add flow control so this
> > needs it will need to be done again. Which is unfortunate for me and
> > anyone with non flow control electronics. I expect this will occur
> > everytime the port is opened. Out of interest do all you serial port
> > tinkerers out there use flow control?
>
> I think you'll have to create a task-specific binding to ioctl(2) to
> set the flow control options before writing to the port.  The fact
> that ioctl(2) is variadic, non-portable and non-standard may explain
> why there is nothing in GNAT.Serial_Communications related to flow
> control.
>
> If you're not sure what arguments to pass to ioctl, maybe you can try:
>
> strace stty --file=/dev/ttyUSB0 -crtscts
>
> --
> Ludovic Brenta.

HHhhmm a task specific binding? is that a c interface just for one
task? I ask because I know I want to do this but just not sure how to,
and I 've not heard of that phrase before.