WHO

Section: User Commands (1)
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BSD mandoc
 

NAME

who - display who is logged in  

SYNOPSIS

who [am I ] [file ]  

DESCRIPTION

The utility who displays a list of all users currently logged on, showing for each user the login name, tty name, the date and time of login, and hostname if not local.

Available options:

am I
Returns the invoker's real user name.
file
By default, who gathers information from the file /var/run/utmp An alternate file may be specified which is usually /var/run/wtmp (or /var/run/wtmp.[0-6] depending on site policy as wtmp can grow quite large and daily versions may or may not kept around after compression by ac(8)). The wtmp file contains a record of every login, logout, crash, shutdown and date change since wtmp was last truncated or created.

If /var/log/wtmp is being used as the file, the user name may be empty or one of the special characters '|', '}' and '~'. Logouts produce an output line without any user name. For more information on the special characters, see utmp(5).  

FILES

/var/run/utmp
/var/log/wtmp
/var/log/wtmp.[0-6]

 

SEE ALSO

last(1), users(1), getuid(2), utmp(5)  

HISTORY

A who command appeared in AT&T System v6 .


 

Index

NAME
SYNOPSIS
DESCRIPTION
FILES
SEE ALSO
HISTORY

This document was created by man2html, using the manual pages.
Time: 06:31:25 GMT, May 19, 2025