"Open: Permission denied" from wall command.

[Rajesh SB]

Hi,

When a normal user broadcasted the message to all using command "wall" getting below error, but still message is reaching to root.

"Cannot send to root"
"Open: Permission denied"

What permission is denied, any pointer on this.

Thanks in advance,

Cheers,
Rajesh

[Mark Grant · Accepted solution]

This means that wall can not open the device file of the terminal that root is using. The user issueing the "wall" would need write access to this file. root can tell which file it is by typing "tty" when logged in.

However, if root is using xterminals or some other pseudo tty device then you would need to have write access to all the /dev/ptys

Hope this helps.

[James Murtagh]

Hi Rajesh,

You need to able to write to the tty of the user that owns it. This is controlled via the mesg command and not by changing permissions directly. As root execute :

# mesg

It will give one of three answers, see "man mesg". If it is set to n, execute as root :

# mesg -y

You can also run tty before and after and see the permissions on the terminal change.

Cheers,

James.

[Rajesh SB]

Hi guys,

Thank a lot for your quick response.
As per mark, I am able to reproduce the problem on other m/c.
This error is due to non-permission to terminal devices.

Cheers,
Rajesh