AC(8) MachTen System Manager’s Manual AC(8)

NAME
ac - connect time accounting

SYNOPSIS
ac [-dp] [-t tty] [-w wtmp] [users ...]

DESCRIPTION
If the file /var/log/wtmp exists, a record of individual login and logout
times are written to it by login(8) and init(8), respectively. Ac exam-
ines these records and writes the accumulated connect time for all logins
to the standard output.

The options are as follows:

-d Display the connect times in 24 hour chunks.

-p Print individual users’ totals.

-t tty Only do accounting logins on certain ttys. The tty specifica-
tion can start with ’!’ to indicate not this tty and end with
’*’ to indicate all similarly named ttys. Multiple -t flags
may be specified.

-w wtmp Read connect time data from wtmp instead of the default file,
/var/log/wtmp.

users ... Display totals for the given individuals only.

If no arguments are given, ac displays the total connect time for all ac-
counts with login sessions recorded in wtmp.

The default wtmp file will increase without bound unless it is truncated.
It is normally truncated by the daily scripts run by cron(8), which re-
name and rotate the wtmp files, keeping a week’s worth of data on hand.
No login or connect time accounting is performed if /var/log/wtmp does
not exist.

For example,

ac -p -t "ttyd*" > modems
ac -p -t "!ttyd*" > other

allows times recorded in modems to be charged out at a different rate
than other.

The ac utility exits 0 on success, and >0 if a fatal error occurs.

FILES
/var/log/wtmp connect time accounting file
/var/log/wtmp.[0-7] rotated files