Ubuntu Manpage: ac - print statistics about users' connect time

NAME

       ac -  print statistics about users' connect time

SYNOPSIS

       ac     [ -d | --daily-totals ] [ -y | --print-year ]
              [ -p | --individual-totals ] [ people ]
              [ -f | --file filename ] [ -a | --all-days ]
              [ --complain ] [ --reboots ] [ --supplants ]
              [ --timewarps ] [ --compatibility ]
              [ --tw-leniency num ] [ --tw-suspicious num ]
              [ -z | --print-zeros ] [ --debug ]
              [ -V | --version ] [ -h | --help ]

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 u*x 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
people. 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 instance). If you want to count this time, include the flag.
*For vanilla ac compatibility, 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 terminal (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
intervening days where there is no login activity. Without this flag, time accrued
during those intervening days gets listed under the next day where there is login
activity.
--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
second one gets written first). By default, this value is set to 60. If the
program notices 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