serial port question

QNX Newsgroups (Archives) qdn.public.qnxrtp.os
1

Is it possible to have a process watching data going in/out of a serial port
without effecting the other process that I have already running on that
serial port ?

This is for both the standard QNX serial port driver and the CTI serial
cards.

Thanks for any ideas/feedback.

2

Brett Wilton <bdwilton@xtra.co.nz> wrote:

Is it possible to have a process watching data going in/out of a serial
port without effecting the other process that I have already running on
that serial port ?

Bret

I don’t know of a way to get the relevant drivers to do that. But you
could write your own resource manager that manages the serial ports and
provides mapped devices that your application can open.

So to monitor /dev/ser1, your resource manager creates a device
/dev/myser1 and your application uses that instead of /dev/ser1. The
resource manager responds to open/read/write/devctl/close etc on
/dev/myser1 by accessing the real /dev/ser1. It can then log or display
traffic as required.

There would be a performance hit involved in this of course.

Hope this helps. If you want someone to write such a process for
you, let me know.

William Morris
william@bangel.demon.co.uk

3

“William Morris” <wrm@bangel.demon.co.uk> wrote in message
news:bkmckf$l90$1@inn.qnx.com…

Brett Wilton <> bdwilton@xtra.co.nz> > wrote:
Is it possible to have a process watching data going in/out of a serial
port without effecting the other process that I have already running on
that serial port ?

Bret

I don’t know of a way to get the relevant drivers to do that. But you
could write your own resource manager that manages the serial ports and
provides mapped devices that your application can open.

So to monitor /dev/ser1, your resource manager creates a device
/dev/myser1 and your application uses that instead of /dev/ser1. The
resource manager responds to open/read/write/devctl/close etc on
/dev/myser1 by accessing the real /dev/ser1. It can then log or display
traffic as required.

Or you could get the source of serial port driver and modify it.

There would be a performance hit involved in this of course.

Hope this helps. If you want someone to write such a process for
you, let me know.

William Morris
william@bangel.demon.co.uk