Linux

I'm hoping someone can help me out here.

I'm having a problem on my Red Hat Enterprise 5 Server where my tty devices "tty[a-d][1-16]" are being set to read only permissions.

I need them to be set to 777 in order to write to the serial printers through a custome application.

I have gone through many article and man pages on how to do this but have had no luck.

from root I can manually chmod the permissions on the devices.

So I attempted to write a script to chmod the devices and place it in the /etc/rc.local file. - This did not work

I created a 51-default.perms file in the console.perms.d directory with the elevated permissions (I have done this with ttyS0 and it has worked reliably)

I have created a 10-udev.rules file and a 99-udev.rules file with the elevated permissions and this did not work.

I have been in touch with red hat support and have had no luck there either.

Has anyone had a similar issue and can you suggest a resolution.

Thanks.

try
ls -lrt /dev/tty*
and look wich user and group they belong
if the group has write permision, add the user runing the app to that group

"tty" is the group that owns the tty[abcd]*
"uucp" is the group that owns ttyS*

However "tty" does not have crwx either.

and for some strange reason tty does not own all the devices. on some the root group is the owner.
Also the permissions are not consistant.
Some are crw--w
and others are crw---

I need crwxrwxrwx.