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?


-- 
Shane Voss, Computing Officer, School of GeoSciences, University of Edinburgh

The University of Edinburgh is a charitable body, registered in
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