Why use "su -" rather than "su"

[Timothy Murphy]

John Bray wrote:

> and in any case, no matter if it is to root or another user, the -
> guarantees you've picked up that user's entire environment.  again, it's
> the key to having consistent behavior when you are being that user, root
> or otherwise.

Could you give an example where the difference matters?
(I usually say "su -" but I'm not really sure why.
When I forget it never seems to cause any problem.)


-- 
Timothy Murphy  
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