OptionsOn who itself
-b
Time of last system boot
-H
Write column headings above the regular output
-l
Print system login processes (unsupported)
-m
Only print information about the current terminal
-p
Print active processes spawned by launchd(8) (unsupported)
-q
'Quick mode': List only names and number of users currently logged on
-r
Print the current runlevel
-s
List only the name, line and time fields (this is the default)
-T
Print a character after the user name indicating the state of the terminal line: '+' writable, '-' not writable, '?' bad
-t
Print last system clock change (unsupported)
-u
Print the idle time for each user and the associated process ID
ArgumentsPositional, in order
<file>
By default, who gathers information from the file /var/run/utmpx; an alternative file may be specified · optional · filepaths
