ac -  print statistics about users' connect time


   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 ]


   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.


   -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.
          When  the  wtmp file has a problem (a time-warp, missing record,
          or whatever), print out an appropriate error.
          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.*
          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.*
          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.*
          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.
          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.


          The system wide login  record  file.  See  wtmp(5)  for  further


   The   GNU   accounting   utilities   were   written   by   Noel   Cragg
   <>. The man page was  adapted  from  the  accounting
   texinfo page by Susan Kleinmann <>.


   login(1), wtmp(5), init(8), sa(8)

                            2010 August 16                           AC(1)


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