Device busy??

Scenario
========
I issued the command :
chdev -l 'tty0' -a parity='odd' and received the following :
Method error (/etc/methods/chgtty):
          0514-062 Cannot perform the requested function because the specified device is busy

Question
========
1) I have checked through 'ps -ef | grep tty0' and there was no such process.  Is this the correct command to issue to find out whether the device is used?

2) How do I make the device not busy as I think my program causes the device to be busy?  I've killed my program but the device is still busy!

3) Is there a command that I can use to test whether tty is working?

NB. My program was working perfectly on another machine's tty!!
Rita060297Asked:
Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

x
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

jos010697Commented:
A device can be in one of three different 'states':

   defined
   stopped
   available

If a device is 'available' (read: busy), some changes can not
be made to the device. You can however use the chdev
command with the '-P' flag. The changes will not be made
immediately then; just the configured device database
will be updated. If you restart the device (normally by
simply rebooting the machine), the device will be changed
accordingly.

You didn't mention your flavor of Un*x your using; check your
manuals for the 'lsdev' command (usually found in /usr/sbin).
It lists all devices and their states ...

kind regards,

Jos aka jos@and.nl
0

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
Rita060297Author Commented:
I've changed the properties of the device port but have problem
opening the port through a C program as the device is busy.
How do I make the device not busy?

FYI, I'm using Korn shell in AIX 4.1
0
jos010697Commented:
Have you checked /dev/ty0's permissions? Do a ls -l /dev/tyt0
and see what permissions are set; I bet it displays something
like:

crw-------   1 root     system    17,  0 Jun 09 07:51 /dev/tty0

in which case you have to have root privileges to access
the console tty ...

kind regards,

Jos aka jos@and.nl
0
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
Unix OS

From novice to tech pro — start learning today.