# ac

## 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 lo‐
           gins/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 ac‐
           counting 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 _people._  Note that _people_ is a space
                  separated list of valid user names; wildcards are not al‐
                  lowed.
           **-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 termi‐
                  nal (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 lo‐
                  gin 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.
    


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