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AC(8) NetBSD System Manager's Manual AC(8)
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by Kimmo Suominen.
Based on man-cgi by Panagiotis Christias.
ac -- display connect time accounting
ac [-d | -p] [-t tty] [-w file] [users ...]
If the file /var/log/wtmp exists, a record of individual login and logout
times are written to it by login(1) and init(8), respectively. The pro-
gram ac examines these records and writes the accumulated connect time
for all logins to the standard output.
-d Display the connect times in 24 hour chunks.
-p Display individual user 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 file Read raw connect time data from file instead of the default
users ... Display totals for the given individuals only.
If no arguments are given, ac displays the total amount of login time for
all active accounts on the system.
The default wtmp file is an infinitely increasing file unless frequently
truncated. This is normally done by the daily daemon scripts scheduled
by cron(8), which rename and rotate the wtmp files before truncating them
(and keep about a week's worth on hand). No login times are collected,
however, if the file does not exist.
ac -p -t "ttyd*" > modems
ac -p -t "!ttyd*" > other
allows times recorded in modems to be charged out at a different rate
The ac utility exits 0 on success, and >0 if a fatal error occurs.
/var/log/wtmp connect time accounting file
/var/log/wtmp.[0-7] rotated files
login(1), utmp(5), init(8), sa(8)
An ac command appeared in Version 6 AT&T UNIX. This version of ac was
written for NetBSD 1.0 from the specification provided by various sys-
tems' manual pages.
NetBSD 5.0.1 April 19, 1994 NetBSD 5.0.1