We help IT Professionals succeed at work.

Who command problem

unicorntech asked
Medium Priority
Last Modified: 2010-03-17
Why would when I type the w or who command on Linux would it only show me the first ten dial-up ttys (ie ttyE0 to
This makes it hard for me to know how long users have been online. What can I do to either fix it or find out how long users have been online???
Watch Question

finger @that.box.com

Not the solution you were looking for? Getting a personalized solution is easy.

Ask the Experts


But how do I know who to finger if they don't show up using who???

Don't finger by name... type it like I had it:
finger @that.box.com

That will tell you everybody logged in.


But I still get the same problem it only shows the users from ttyE0 to ttyE9 and when the tty goes to double figures like ttyE11 it doesn't show up???


Adjusted points to 75

okay.  what about "ps -ax | grep e[0-100]"
make an alias for it of course... don't want to be typing
that every time.


Thanks for the comment but that is what I've been doing except I've been doing "ps -ax|grep pppd" and that tells me how many ppp processes are running but not who is using them. What I really need to know is why who doesn't work and what I need to do to fix it. Please help 'cause the comments so far are great!!

May be there are corrupted /etc/{w,u}tmp  (or whereever they
reside) files. Remove them carefully.

try "last -20" for last 20 logons. Users who is online now
will be marked as "still logged in", for all other you will
see login/logout/total time.

Of course, you can grep it, if you need only
logged in users. :)


I've been looking thru the utmp.h file and found an entry for the length of the tty entry output. This is set to [2] - should I perhaps change this to [3], recompile and reinstall the kernel?

Kernel is not responsible for handling [wu]tmp files.
It is responsibility of programs like "login", "getty".
And, many programs depends on format of utmp file.

You can change it, of course, but after this you need
to recompile all programs which use it. At least, you
need to recompile: login, getty, agetty, mgetty, who,
finger, last...

But, look at utmp.h more close: entry, responsible for
storing device (line) name [ut_line], is 12 bytes long. And info
about tty stored here.

Devario JohnsonPrincipal Software Engineer

Does anyone know of a program that tells an administrator can check to see how how long users are logged into a client machine on a network?

Win 2000 pro
Access more of Experts Exchange with a free account
Thanks for using Experts Exchange.

Create a free account to continue.

Limited access with a free account allows you to:

  • View three pieces of content (articles, solutions, posts, and videos)
  • Ask the experts questions (counted toward content limit)
  • Customize your dashboard and profile

*This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.


Please enter a first name

Please enter a last name

8+ characters (letters, numbers, and a symbol)

By clicking, you agree to the Terms of Use and Privacy Policy.