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       writetmp - write special wtmp entries to a wtmp file.


       writetmp  [-w  wtmp|-]  [-X[3|4]] [-u user] [-l line] [-h host] [-i id]
       [-p pid] [-t type] [-c comment] [--help] [--version] [entry-type]


       Writetmp is a utility to write special entries to a wtmp file.   Useful
       as  either  a  replacement  for  the  functionality of the "halt -w" or
       "reboot -w" commands which are normally run  at  shutdown  time  or  to
       write  special  wtmp  entries  to  an alternate wtmp file to which such
       entries would normally not be written.

       Under normal conditions radius radtwmp or tacacs accounting logs do not
       contain  shutdown  and  boottime  entries  because  the  access control
       software is not setup to take into account these events.  In  the  case
       of  a  quick  shutdown  or  server  crash,  the  wtmp file(s) will lose
       coherency.  To avoid or minimize the amount of accounting error, it  is
       necessary to write shutdown and boottime entries to such logs.

       Also  changes  in  time  which  are  made manually with date or via the
       network with  a  program  such  as  rdate  are  not  reflected  in  the
       accounting logs, which, if the time difference is severe can improperly
       account time for logins active during the time change.

       If an entry-type is specified on the command line, the -u, -l, -h,  -i,
       -p,  -t  and  -c  options  are  ignored  as  writetmp  will fill in the
       username, line, id, and host entries as required  for  that  particular
       wtmp entry-type.

       Writetmp understands the following entry types:

              used  just prior to a normal system shutdown.  Also accepts halt
              or reboot as aliases for shutdown.

              used at system initialization time, to indicate  the  system  is

              Indicates the time is about to change.

              Indicates  the  time  has  changed.   The  difference in time is
              determined from the timestamp on the last oldtime entry.

              Indicates a change in runlevel (useless in an accounting sense).


       Writetmp understands the following command line switches:

       --help Outputs a verbose usage listing.

              Displays the version of writetmp.

       -w wtmp
              Select   a   different   output  file  instead  of  the  default

       -X[3]  Write to a wtmp file maintained by versions 3.3  or  3.4  Tacacs
              terminal server access control software.

       -X4    Write  to  a  wtmp  file  maintained  by  version  4.0 of Tacacs
              terminal server access control software.

       -u user
              Specify the username for the username field.

       -l line
              Specify the tty name for the line field.

       -h host
              Specify the hostname.

       -i id  Specify the init id name. Not applicable to tacacs wtmp files.

       -p pid Specify the pid number. Not appliccable to tacacs wtmp files.

       -t type
              Specify the type of wtmp entry for the ut_type field, not to  be
              confused  with  entry-type.  May be coded as a number or one of:
              unknown, runlevel, boottime, newtime, oldtime, init, login, user
              or dead.

       -c comment
              Specify  the  comment  for  the  tacacs 4 wtmp comment field (16
              characters max).


       Write a shutdown message to an alternate wtmp log:

            writetmp -w /var/adm/xtmp shutdown

       A shell script to update the  time  in  an  alternate  wtmp  file  when
       netdate is run:

            writetmp -w /var/adm/xtmp oldtime
            writetmp -w /var/adm/xtmp newtime

       Find out how often and for how long people run a specific program, such
       as pine:

            # /var/adm/cmdtmp must be globally writable.

            writetmp -w $cmdtmp -u pine -l cmd$$ -h $USER -t user
            /path/to/real-pine $*
            writetmp -w $cmdtmp -l cmd$$ -t dead


       /var/log/wtmp        login database.


       Steve Baker (


       Does not lock the wtmp file and does not guarantee a successful  write.
       Could in theory corrupt a log file.

       Rdate   and   netdate   can   take  seconds  to  complete,  so  writing
       oldtime/newtime records around them may not be entirely accurate.


       date(1), last(1), sac(8), netdate(8L), reboot(8)