phpman > man > ac(1)

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⚡ TLDR: ac (tldr-pages)

Print statistics on how long users have been connected.

Print how long the current user has been connected in hours
ac
Print how long users have been connected in hours
ac -p
Print how long a particular user has been connected in hours
ac -p {{username}}
Print how long a particular user has been connected in hours per day (with total)
ac -dp {{username}}

AC(1) General Commands Manual AC(1)

NAME
ac - print statistics about users' connect time

DESCRIPTION
ac prints out a report of connect time (in hours) based on the logins/logouts in the current
wtmp file. A total is also printed out.

The accounting file wtmp is maintained by init(8) and login(1). Neither ac nor login creates
the wtmp if it doesn't exist, no accounting is done. To begin accounting, create the file
with a length of zero.

NOTE: The wtmp file can get really big, really fast. You might want to trim it every once
and a while.

GNU ac works nearly the same UNIX ac, though it's a little smarter in several ways. You
should therefore expect differences in the output of GNU ac and the output of ac's on other
systems. Use the command info accounting to get additional information.

OPTIONS
-d, --daily-totals
Print totals for each day rather than just one big total at the end. The output looks
like this:
Jul 3 total 1.17
Jul 4 total 2.10
Jul 5 total 8.23
Jul 6 total 2.10
Jul 7 total 0.30
-p, --individual-totals
Print time totals for each user in addition to the usual everything-lumped-into-one
value. It looks like:
bob 8.06
goff 0.60
maley 7.37
root 0.12
total 16.15
people Print out the sum total of the connect time used by all of the users included in peo‐
ple. Note that people is a space separated list of valid user names; wildcards are
not allowed.
-f, --file filename
Read from the file filename instead of the system's wtmp file.
--complain
When the wtmp file has a problem (a time-warp, missing record, or whatever), print out
an appropriate error.
--reboots
Reboot records are NOT written at the time of a reboot, but when the system restarts;
therefore, it is impossible to know exactly when the reboot occurred. Users may have
been logged into the system at the time of the reboot, and many ac's automatically
count the time between the login and the reboot record against the user (even though
all of that time shouldn't be, perhaps, if the system is down for a long time, for in‐
stance). If you want to count this time, include the flag. *For vanilla ac compati‐
bility, include this flag.*
--supplants
Sometimes, a logout record is not written for a specific terminal, so the time that
the last user accrued cannot be calculated. If you want to include the time from the
user's login to the next login on the terminal (though probably incorrect), include
this you want to include the time from the user's login to the next login on the ter‐
minal (though probably incorrect), include this flag. *For vanilla ac compatibility,
include this flag.*
--timewarps
Sometimes, entries in a wtmp file will suddenly jump back into the past without a
clock change record occurring. It is impossible to know how long a user was logged in
when this occurs. If you want to count the time between the login and the time warp
against the user, include this flag. *For vanilla ac compatibility, include this
flag.*
--compatibility
This is shorthand for typing out the three above options.
-a, --all-days
If we're printing daily totals, print a record for every day instead of skipping in‐
tervening days where there is no login activity. Without this flag, time accrued dur‐
ing those intervening days gets listed under the next day where there is login activi‐
ty.
--tw-leniency num
Set the time warp leniency to num seconds. Records in wtmp files might be slightly
out of order (most notably when two logins occur within a one-second period - the sec‐
ond one gets written first). By default, this value is set to 60. If the program no‐
tices this problem, time is not assigned to users unless the --timewarps flag is used.
--tw-suspicious num
Set the time warp suspicious value to num seconds. If two records in the wtmp file
are farther than this number of seconds apart, there is a problem with the wtmp file
(or your machine hasn't been used in a year). If the program notices this problem,
time is not assigned to users unless the --timewarps flag is used.
-y, --print-year
Print year when displaying dates.
-z, --print-zeros
If a total for any category (save the grand total) is zero, print it. The default is
to suppress printing.
--debug
Print verbose internal information.
-V, --version
Print the version number of ac to standard output and quit.
-h, --help
Prints the usage string and default locations of system files to standard output and
exits.
FILES
wtmp
The system wide login record file. See wtmp(5) for further details.
AUTHOR
The GNU accounting utilities were written by Noel Cragg <noel AT gnu.edu>. The man page
was adapted from the accounting texinfo page by Susan Kleinmann <sgk AT sgk.net>.
SEE ALSO
login(1), wtmp(5), init(8), sa(8)

2010 August 16 AC(1)

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