Yep write is blocked but not wall.

And as Shane says super user is not blocked. (Thanks Shane :-) )

What worried me is that the man page for wall says:

snip---

Wall  sends a message to everybody logged in with their mesg(1) permis-
        sion set to yes.

snip---

But look at this test on Sl5.5:

fgibbins@comp ~ 0$ tty
/dev/pts/0
fgibbins@comp ~ 0$ mesg n
fgibbins@comp ~ 0$ wall foo

Broadcast message from fgibbins (pts/0) (Thu Nov 25 08:48:53 2010):

foo
fgibbins@comp ~ 0$ ls -l `which wall`
-r-xr-sr-x 1 root tty 10484 Jan 21  2009 /usr/bin/wall
fgibbins@comp ~ 0$ ls -l /dev/pts/0
crw------- 1 fgibbins tty 136, 0 Nov 25 08:50 /dev/pts/0
fgibbins@comp ~ 0$

Strange no?

Faye

PS I am not a super user.

On 24/11/10 18:59, Shane Voss wrote:
> The man page for  write  (and for  wall  on another well known distro)
> mention that mesg does not block the super-user. I suspect this may be
> the cause of the confusion.
>
> Shane
>
>> I tested it on i386 SL5.1 with 'write yellin pts/6', where "yellin" is my
>> username on that computer and "pts/6" is the ttyname on which I had typed
>> 'mesg n'. The 'write ...' command was blocked to that terminal, though
>> not to
>> any of my other terminals for which 'mesg' returned "y". So as far as
>> I can
>> tell, 'mesg n' does what it's supposed to do.
>>
>> Steven Yellin
>>
>> On Wed, 24 Nov 2010, Faye Gibbins wrote:
>>
>>> Anyone know why 'mesg n' doesn't stop 'write' anymore on SL5.x?
>
>


-- 
---------------------------------------------------------
Faye Gibbins, Sys Admin.  GeoS KB.  Linux, Unix, Security
Beekeeper  - The Apiary Project, KB -   www.bees.ed.ac.uk
---------------------------------------------------------
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