NAME
ac - login accounting

SYNOPSIS
ac [ -w wtmp ] [ -p ] [ -d ] [ people ] ...

DESCRIPTION
Ac produces a printout giving connect time for each user who has
logged in during the life of the current wtmp file. A total is
also produced. -w is used to specify an alternate wtmp file. -p
prints individual totals; without this option, only totals are
printed. -d causes a printout for each midnight to midnight
period. Any people will limit the printout to only the specified
login names. If no wtmp file is given, /usr/adm/wtmp is used.

The accounting file /usr/adm/wtmp is maintained by init and login.
Neither of these programs creates the file, so if it does not exist
no connect-time accounting is done. To start accounting, it should
be created with length 0. On the other hand if the file is left
undisturbed it will grow without bound, so periodically any
information desired should be collected and the file truncated.

FILES
/usr/adm/wtmp

SEE ALSO
init(8), sa(8), login(1), utmp(5).