Displays information about the current status of the system. With no options, lists the names of users currently logged into the system. An optional system file (default is /var/run/utmp) can be supplied to give additional information. who is usually invoked without options, but useful options include am i and -u. For more examples, see cut , line, paste , tee , and wc .
Report only about the current terminal.
List names and number of users in columns.
Report whether terminals are writable (
+), not writable (
-), or unknown (
Report terminal usage (idle time). A dot (.) means less than one minute idle; old means more than 24 hours idle.
Print the username of the invoking user. (Similar to results from id.)
This sample output was produced at 1:55 p.m. on January 15:
who -uHUSER LINE WHEN IDLE FROM chuck console Jan 14 19:55 18:01 chuck ttyp1 Jan 15 13:11 . chuck ttyp2 Jan 15 13:55 .
The output shows that the user chuck has been idle for 18 hours and 1 minute (18:01, under the IDLE column).