su, su -, sudo _and runuser_

[Rainer Traut]

Hi,

Tim schrieb:
> Gayal asked:
>>>>  Wuts the different between su, su - root and sudo ?

I think a better question is what is 'runuser' for?
It has less options than su but does the same thing?!

Thx
Rainer

> 
> Jafar concisely answered:
>>>  su will let you run a shell with substitute user without
>>> making the shell a login shell.
>>>  su - will let you run a shell with substitute user and make the shell
>>> a login shell. If you put no username, it assumes as root (same as su)
> 
> Minor elaboration:   "su - root" is the same as "su -".  While the
> omission or inclusion of the username is the same in "su" as "su -", the
> response could have been interpreted as "su -" = "su".
> 
>>>  sudo will let you run certain or all commands as if you are
>>> root, depending on the settings on visudo file.