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Basic use of who, cut, grep and pipes??

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# 1  
Old 02-12-2012
Basic use of who, cut, grep and pipes??
Hi, I'm new to shell scripting and i'm trying to write code which contains exactly three pipe commands (e.g. A | B | C) to return a list of the users currently logged into the system. I've been told three useful commands i could use are who, grep and cut. I know 'who' return a list of the users logged in with some information about them and a combination of the other two might be able to extract the exact user name. Can anyone help me out? Thanks.
# 2  
Old 02-12-2012
This sounds like homework. For that kind of requests we have special subforum: Homework & Coursework Questions. Read and follow rules that govern it.
# 3  
Old 02-12-2012
First thing when posting questions is to mention what Operating System and Version you have and what Shell you prefer.

We guess that the output you require is more interesting than just typing the "who" command. The output from "who", "who -q" and "who -u" has much variety across Operating Systems and versions.

It's usual to show sample input and sample output with an explanation of the process.

To us the "user name" would be the login name of the user. You might be referring to the Comments field in the password file and you might not.
# 4  
Old 02-12-2012
i'm using ubuntu 11.10...sorry I wasn't very specific.
# 5  
Old 02-12-2012
Please post sample input and expected output. We don't know what the output from your "who" command looks like or what your intended output should look like. While doing this perhaps post some of your ideas and tests.
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