su and su - commands

[Just17]

Just su to root and use the rest of the line.

Should not that be su - ?

If using one of the newer ISOs you may find that "su" is aliased to "su -" .......  you can find out what aliases are set up by typing in a terminal

alias

[dvhenry]

On my system that alias is not set up, but I use a variety of distro's,  so will stick to my already formed habit of typing "su -".

[johnmart]

Excuse me for butting in with an off-topic question.
Is there a downside to using su -, instead of su?
I never use su - unless I am following someone's advice.
My concern is that the results of certain commands from root environment could cause an ownership issue later on.
But I am a dummy.  
Unfounded concern?

[jfdesign]

Just su to root and use the rest of the line.

Should not that be su - ?

If using one of the newer ISOs you may find that "su" is aliased to "su -" .......  you can find out what aliases are set up by typing in a terminal

alias

i'm not gonna install the new iso in near time because my system is in good shape, but i want that alias. may i know how tex set that alias ? if in .bash_profile ... what the syntax ?
tia

[Old-Polack]

Just su to root and use the rest of the line.

Should not that be su - ?

If using one of the newer ISOs you may find that "su" is aliased to "su -" .......  you can find out what aliases are set up by typing in a terminal

alias

i'm not gonna install the new iso in near time because my system is in good shape, but i want that alias. may i know how tex set that alias ? if in .bash_profile ... what the syntax ?
tia

You can add a line to your ~/.bashrc;

alias su='su -'

Save the file and that's it.

[Just17]

Just su to root and use the rest of the line.

Should not that be su - ?

If using one of the newer ISOs you may find that "su" is aliased to "su -" .......  you can find out what aliases are set up by typing in a terminal

alias

i'm not gonna install the new iso in near time because my system is in good shape, but i want that alias. may i know how tex set that alias ? if in .bash_profile ... what the syntax ?
tia

http://www.mediacollege.com/linux/command/alias.html

[Bald Brick]

Excuse me for butting in with an off-topic question.
Is there a downside to using su -, instead of su?

Perhaps a few minor annoyances.

For instance: when you run "su" your current directory remains your current directory; but after running "su -" your current directory always becomes /root. So if you want to run a command on a file in what used to be your current directory, you have to specify the path to it, or cd back to it.

Note that if you su to root and a program needs root's envirenment, you don't have to exit and start again with "su -" and root's password; just type "su -" as root and you'll get the whole environment.

I never use su - unless I am following someone's advice.
My concern is that the results of certain commands from root environment could cause an ownership issue later on.
But I am a dummy.  
Unfounded concern?

If you create a file or a folder as root that file or folder will be owned by root regardless of whether you've run "su" or "su -" to become root.

[jfdesign]

thank you old_polack and just19 for the help.  

[dvhenry]

A discussion on "su" verses "su -" that may be of interest to some is http://forums.opensuse.org/new-user-how-faq-read-only/unreviewed-how-faq/424498-become-su-terminal-howto.html
The discussion starts at post #7, and gets more interesting and detailed around post #20.
 It is from the openSUSE forums, but contains relevant info.

[johnmart]

Thanks BaldBrick. Cleared it up for me.  
Thanks too dvhenry. I'll give that a look. Haven't been there since suse.6, or was it 9?  

[dvhenry]

Thanks too dvhenry. I'll give that a look. Haven't been there since suse.6, or was it 9?

It's an interesting read, and worth a look.

At this point, might I suggest that a moderator move posts from reply #15 on, to a separate thread with an appropriate title, as this has become 2 subjects.
Those interested in variations of the "su" command are not likely to start looking in a thread about UUIDs.

[Archie]

Where are these new set of aliases hardcoded??

I've looked in the .bashrc, /etc/profile, /etc/profile.d/60alias.sh ... and can't seem to find it.

[AS]

Where are these new set of aliases hardcoded??

I've looked in the .bashrc, /etc/profile, /etc/profile.d/60alias.sh ... and can't seem to find it.

/home/<user>/.bashrc

'su=su -' alias has been added in recent PCLinuxOS versions (kde-2011-06, -kde-minime-2011-07, ...),
you can't find it in your installation if you are rolling up from previous releases   

AS

[Archie]

Thanks, AS.

I must be getting blind. I was expecting a whole bunch of aliases, i.e. .bash_aliases ... and thanks to you, I found it at the end of the .bashrc line.      LOL.

[Vorteggs]

There's a related command unalias for those interested in.