OSF

NAME

who − Identifies users currently logged in

SYNOPSIS

who [-a] | [-AbdHlpqrstTu] [file]

who am i

The who command displays information about users and processes on the the local system. 

FLAGS

-aSpecifies all options; processes /var/adm/utmp or the named file with all flags on. 

-ADisplays accounting entries. 

-bIndicates the most recent system start-up time and date.  The LC_TIME environment variable controls the format of the login time and date. 

-dDisplays all processes that have expired without being regenerated by init.  The exit_status field appears for dead processes and contains the termination and exit values (as returned by wait) of the dead processes.  (This flag is useful for determining why a process ended.) 

-HDisplays a header (title). 

-lLists only terminals not in use.  The user field is LOGIN in such cases.  Other fields are the same as for user entries except that the state field does not appear. 

-pLists any active process that is currently active and was previously generated by init. 

-qPrints a quick listing of users and the number of users on the local system. 

-rIndicates the current run-level of the system. 

-sLists only the user, line, time, and host (if not null) fields.  (This is the default; thus, who and who -s are equivalent.)  The LC_TIME environment variable controls the format of the time. 

-tIndicates the last change to the system clock by the superuser using the date command.  The LC_TIME environment variable controls the format of the time. 

-TDisplays the status of the terminal line and indicates who can write to that terminal as follows:

+Writable by anyone. 

-Writable only by the superuser or its owner. 

?Bad line encountered. 

-uDisplays the username, terminal name, login time, line activity, and process-ID of each current user.  The LC_TIME environment variable controls the format of the login time. 

DESCRIPTION

The who command displays the following information for the users and/or processes you specify:

       •Login name

       •Terminal name

       •Date

       •Time of login

       •Host

Entering who am i displays your login name, terminal name, date and time you logged in, and host. 

With flags, who can also display the elapsed time since line activity occurred, the process-ID of the command interpreter (shell), logins, logouts, restarts, and changes to the system clock, as well as other processes generated by the init process. 

The general output format of the who command is as follows:

user [state] line time activity process_ID [exit_status]

where:

       •user is the user’s login name. 

       •state indicates whether or not the line is readable by everyone (see the -T flag). 

       •line is the name of the line as found in the /dev directory. 

       •time is the time that user logged in. 

       •activity is the hours and minutes since activity last occurred on that user’s line.  A . (dot) here indicates line activity within the last minute.  If the line has been quiet more than 24 hours or has not been used since the last system start-up, the entry is marked as old. 

       •process_ID is the process-ID of the user’s shell. 

       •exit_status is the exit status of ended processes (see the -d flag). 

To obtain its information, who normally examines /var/adm/utmp.  If you specify another file, who examines the named file instead.  This file will usually be /var/adm/wtmp, which contains the history of all logins since the file was last created. 

Note that who only identifies users on the local node. 

EXAMPLES

     1.To display information about who is using the local system, enter:

who

Information similar to the following is displayed:

george  console Jun 8  08:34  (abcpa.pasc.abc.c)

     2.To display your username, enter:

who am i

huangconsole Jun 808:34  (maguro)

     3.To display a history of logins, logouts, system start-ups, and system shutdowns, enter:

who  /var/adm/wtmp

Information similar to the following is displayed:

huangconsoleJun 808:34
johnconsoleJun 808:34
rachelconsoleJun 808:22
spikettyp4Jun 809:19

     4.To find out who is logged on to the local system, enter:

who -A

betty
svi

     5.To display the run-level of the local system, enter:

who -r

run-level  2  June 8  04:15  from:S  to:2  by pid:0

     6.To display any active process that is currently active and was previously generated by init, enter:

who -p

Information similar to the following is displayed:

.tty4Jun 804:15
.tty7Jun 804:15
.tty14Jun 804:15

FILES

/var/adm/utmpContains user and accounting information. 

/var/adm/wtmpContains login history. 

RELATED INFORMATION

Commands:  date(1), init(8), login(1), mesg(1), su(1), whoami(1). 

Functions:  wait(2). 

Files:  utmp(4).