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find out who you logged onto the machine as -- and not just who you are now

Terminal - find out who you logged onto the machine as -- and not just who you are now
who am i
2009-02-20 16:26:11
User: ozymandias
Functions: who
-18
find out who you logged onto the machine as -- and not just who you are now

In my work environment, we log onto the servers as our user ('user', in the sample ouput), and 'sudo su - root' to other accounts. This trick allows us to return the account name we logged in as -- and not the account name we currently are ('root', in this example).

Using this trick, you can build other commands:

Set your CVSROOT env variable to your account name:

CVSROOT=$(who am i | awk '{print $1}')@cvs.server.example.com:/cvsroot

SCP a file to another server:

scp file.txt $(who am i | awk '{print $1}')@some.other.server.com:.

This works out great in my environment, as we can include this in our documentation and make the comands more easy to copy/paste for different users, and not have to set all sorts of variables, or modify the docs for each user.

whoami gives you the name of the user you currently are, not the user you logged on originally as.

who gives you a listing of every single person logged onto the server.

who am i gives you the name of the user you logged on as, and not who you changed to with su.

Look at the following scenario:

whoami

user

su -

# whoami

root

# who am i

user pts/51 2009-02-13 10:24 (:0.0)

whoami != who am i

Alternatives

There are 2 alternatives - vote for the best!

Terminal - Alternatives

Know a better way?

If you can do better, submit your command here.

What others think

so is there a shell that this actually works on? Maybe you mean 'whoami' ?

Comment by bartman 286 weeks and 5 days ago

or maybe just 'who' ?

Comment by bartman 286 weeks and 5 days ago

Those are actually all distinct.

'who am i' gives you just the line of the 'who' output that relates

to your current session. whoami gives you your current username

and who gives you the complete list of logged in users including terminal

time and origination info.

As a side note, the critical thing is the *number* of arguments to 'who' and the 'am i' is just used as a mnemonic device. In face it's faster to type

who o o

which does the same thing.

Still, not really a 'Fu' command, though.

Comment by adminzim 286 weeks and 5 days ago

@adminzim

who o o

usage: who [-HmqsTu] [am I] [file]

whoami

grep

also works

Comment by grep 286 weeks and 5 days ago

bartman

whoami gives you the name of the user you currently are, not the user you logged on originally as.

who gives you a listing of every single person logged onto the server.

who am i gives you the name of the user you logged on as, and not who you changed to with su.

Grep, look at the following scenario:

whoami

user

su -

#whoami

root

#who am i

user pts/51 2009-02-13 10:24 (:0.0)

whoami != who am i

Comment by ozymandias 286 weeks and 5 days ago

bartman,

Also, this seems to work on the following machines -- and I just confirmed : RHEL3,4,5, (and CentOS), Fedora 8,9,10, Debian Etch, Sid, Ubuntu 7.10, 8.4, 8.10, 9.04 alpha, Solaris 9, 10, all with bash.

I tested ksh on the RHEL3,4,5, Fedora, and Solaris hosts, and they all worked in my test environment. I am not sure what shell/OS you are using, or if we perhaps installed some package on all these, but I doubt it.

Comment by ozymandias 286 weeks and 5 days ago

On Debian/Lenny, it seems that it does not work if I run it from an xterm. If I ssh in, it works. In both cases running just 'who' works.

Comment by bartman 286 weeks and 5 days ago

bartman,

When I run who, I get output for each user logged on with no indication of which one 'I' am...

Comment by ozymandias 286 weeks and 5 days ago

@grep

[zim@host ~]$ who o o

zim pts/4 2009-02-20 14:33 (:0.0)

gnu coreutils.

Comment by adminzim 286 weeks and 5 days ago

Your point of view

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