xhost: unable to open display ":0.0"

[jbk at mail2.gis.net (jbk)]

jbk wrote:
> David Kramer wrote:
> 
>> jbk wrote:
>>
>>> # su -
>>> -bash: \e[3~:delete-char: command not found
>>> Xlib: connection to ":0.0" refused by server
>>> Xlib: No protocol specified
>>>
>>> xhost:  unable to open display ":0.0"
>>>
>>> This symptom occured after upgrading Fc3 to Fc4. It only happens when 
>>> I login as root locally. If I SSH from another machine and then 'su 
>>> -' I have no trouble.
>>>
>>> "xhost +localhost" is defined in root's .bash_profile.
>>>
>>> A fresh install on my laptop did not exhibit this problem.
>>>
>>> I am googling the mailing lists but have yet to find reference to 
>>> this particular circumstance.
>>
>>
>>
>> I assume you started X as a regular user.  That regular user has to 
>> adjust the security of the X session, not root.  Put the "xhost 
>> +localhost" in _that_ user's .bash_profile.
> 
> 
> It is. In fact if I just "su" instead of "su -" I have no problem.

I just discovered a subtilety in the behavior. If I "su -" 
directly from user I do not have the problem. It is when I 
first "su" and then "su -" that xhost is unable to open the 
display.
So does this narrow the possibilities? I have two Fc4 
systems I can compare. Or should I leave it as a quirk that 
isn't worth figuring out?