Be alert for the heimdal port's instance of "su"

[Ryan Schmidt]

On Apr 16, 2007, at 06:28, Tabitha McNerney wrote:

> $ sudo su - postgres81
>
> Whoops! That "su" is not the "su" you might be thinking of. That  
> "su" is:
>
> /path/to/macports/bin/su as in /opt/local/bin/su
>
> installed by the heimdal port.

A bit unrelated to your question, but: I've seen others use "sudo su  
-" but I haven't understood it. Why not use "sudo -s"? Isn't that  
equivalent?