Who's On? (Unix Power Tools, 3rd Edition) 2.8. Who's On? The who command lists the users logged on to the system now. Here's an example of the output on my system: % who naylor ttyZ1 Nov 6 08:25 hal ttyp0 Oct 20 16:04 (zebra.ora.com:0.) pmui ttyp1 Nov 4 17:21 (dud.ora.com:0.0) jpeek ttyp2 Nov 5 23:08 (jpeek.com) hal ttyp3 Oct 28 15:43 (zebra.ora.com:0.) ... Each line shows a different terminal or window. The columns show the username logged on, the tty (Section 2.7) number, the login time, and, if the user is coming in via a network (Section 1.21), you'll see their location (in parentheses). The user hal is logged on twice, for instance. It's handy to search the output of who with grep (Section 13.1) -- especially on systems with a lot of users. For example: % who | grep "^hal " ...where is hal logged on? % who | grep "Nov 6" ...who logged on today? -v Section 13.3 % who | grep -v "Nov 6" ...who logged on before today? ... The GNU who, on the CD-ROM [see http://examples.oreilly.com/upt3], has more features than some other versions. -- JP 2.7. What tty Am I On?2.9. The info Command Copyright © 2003 O'Reilly & Associates. All rights reserved.