<div>
I've changed the properties of the device port but have problem<br />
opening the port through a C program as the device is busy.<br />
How do I make the device not busy?<br />
<br />
FYI, I'm using Korn shell in AIX 4.1 <br />

</div>


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


<div>
Have you checked /dev/ty0's permissions? Do a ls -l /dev/tyt0<br />
and see what permissions are set; I bet it displays something<br />
like: <br />
<br />
crw------- &nbsp; 1 root &nbsp; &nbsp; system &nbsp; &nbsp;17, &nbsp;0 Jun 09 07:51 /dev/tty0<br />
<br />
in which case you have to have root privileges to access<br />
the console tty ...<br />
<br />
kind regards,<br />
<br />
Jos aka jos@and.nl<br />

</div>


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


<div>
<div class="content wysiwyg-content">
Scenario<br />
========<br />
I issued the command :<br />
chdev -l 'tty0' -a parity='odd' and received the following :<br />
Method error (/etc/methods/chgtty):<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; 0514-062 Cannot perform the requested function because the specified device is busy<br />
<br />
Question <br />
========<br />
1) I have checked through 'ps -ef | grep tty0' and there was no such process. &nbsp;Is this the correct command to issue to find out whether the device is used?<br />
<br />
2) How do I make the device not busy as I think my program causes the device to be busy? &nbsp;I've killed my program but the device is still busy!<br />
<br />
3) Is there a command that I can use to test whether tty is working?<br />
<br />
NB. My program was working perfectly on another machine's tty!!<br />

</div>
</div>


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!!


Device busy??

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