Who command, Linux

From NetworkCommands

A command line program available on most Linux platforms; used to display who is logged on to the device.

Usage Syntax

who [-options]

Some of the available options are;

• -a - display all possible output (i.e. all options selected)
• -b - display time of last boot
• --login - display system login processes
• -s - display only name, line, and time (this is the default)

Linux Usage Notes

With most Linux or Unix commands;

• Brief help can be displayed using the option/keyword: -h or --help, for example: chmod --help
• A full command manual can be displayed using the man command followed by the command name, for example: man chmod
• Sometimes 'info' pages are used instead of or to provide more information than man pages; for example: info chmod
• Version information can be display using the option/keyword: -v or --version, for example: chmod --version

Typical Output

who;

testuser  pts/0        Feb 28 11:44 (11.12.13.100)

who -b;

system boot  Dec 11 18:14

who --login;

LOGIN    ttyS0        Dec 11 18:14              1525 id=co

who -a;

                        Dec 11 18:14                17 id=si    term=0 exit=0
           system boot  Dec 11 18:14
           run-level 3  Dec 11 18:14                   last=S
                        Dec 11 18:14               873 id=l3    term=0 exit=0
                        Dec 11 18:14              1523 id=SV
                        Dec 11 18:14              1524 id=od
LOGIN      ttyS0        Dec 11 18:14              1525 id=co
testuser + pts/0        Feb 28 11:44   .          4107 (11.12.13.100)
           pts/1        Feb 28 13:50              6340 id=ts/1  term=0 exit=0

Command Equivalents

The Zebra routing application suite command equivalent has the same name: who command, Zebra

The Cisco command equivalent is the who command, Cisco or the show users command which performs the same function

The Cisco CSS command equivalent is the show lines command

The Extreme command equivalent is the show session command, which includes ssh connection information.

Related Articles

Information on Linux commands

Information on F5 BigIP commands

Information on Cisco commands

Information on Vyatta commands

Information on Extreme commands

Information on Blue Coat SGOS commands

Information on Nokia IPSO commands

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