sessreg - manage utmpx/wtmpx entries for non-init clients
sessreg [-w wtmpx-file] [-u utmpx-file] [-L
  lastlog-file] [-l line-name] [-h host-name] [-s
  slot-number] [-x Xservers-file] [-t ttys-file] [-V] [-a]
  [-d] user-name
Sessreg is a simple program for managing utmpx/wtmpx and lastlog entries
  for xdm sessions.
System V has a better interface to utmp than BSD; it dynamically
    allocates entries in the file, instead of writing them at fixed positions
    indexed by position in /etc/ttys.
To manage BSD-style utmp files, sessreg has two strategies.
    In conjunction with xdm, the -x option counts the number of lines in
    /etc/ttys and then adds to that the number of the line in the
    Xservers file which specifies the display. The display name must be
    specified as the "line-name" using the -l option. This sum is used
    as the "slot-number" in the utmp file that this entry will be
    written at. In the more general case, the -s option specifies the
    slot-number directly. If for some strange reason your system uses a file
    other than /etc/ttys to manage init, the -t option can direct
    sessreg to look elsewhere for a count of terminal sessions.
Conversely, System V managers will not ever need to use these
    options (-x, -s and -t). To make the program easier to document and explain,
    sessreg accepts the BSD-specific flags in the System V environment
    and ignores them.
BSD and Linux also have a host-name field in the utmp file which
    doesn't exist in System V. This option is also ignored by the System V
    version of sessreg.
This version of sessreg is built using the modern POSIX
    pututxline(3c) interfaces, which no longer require the slot-number,
    ttys-file, or Xservers-file mappings. For compatibility with older versions
    and other operating systems, the -s, -t, and -x flags
    are accepted, but ignored.
In Xstartup, place a call like:
       sessreg -a -l $DISPLAY -x /etc/X11/xdm/Xservers $USER
and in Xreset:
       sessreg -d -l $DISPLAY -x /etc/X11/xdm/Xservers $USER
  - -w wtmpx-file
- This specifies an alternate wtmpx file, instead of /var/log/wtmp.
      The special name "none" disables writing records to the wtmpx
      file.
- -u utmpx-file
- This specifies an alternate utmpx file, instead of /var/run/utmp.
      The special name "none" disables writing records to the utmpx
      file.
- -L lastlog-file
- This specifies an alternate lastlog file, instead of lastlogx, if
      the platform supports lastlog files. The special name "none"
      disables writing records to the lastlog file.
- -l line-name
- This describes the "line" name of the entry. For terminal
      sessions, this is the final pathname segment of the terminal device
      filename (e.g. ttyd0). For X sessions, it should probably be the local
      display name given to the users session (e.g. :0). If none is specified,
      the terminal name will be determined with ttyname(3) and stripped of
      leading components.
- -h host-name
- This is set to indicate that the session was initiated from a remote host.
      In typical xdm usage, this options is not used.
- -s slot-number
- Each potential session has a unique slot number in BSD systems, most are
      identified by the position of the line-name in the
      /etc/ttysfile. This option overrides the default position
      determined with ttyslot(3). This option is inappropriate for use with xdm,
      the -x option is more useful. This option is accepted for compatibility,
      but does nothing in this version of sessreg.
- -x Xservers-file
- As X sessions are one-per-display, and each display is entered in this
      file, this options sets the slot-number to be the number of lines
      in the ttys-file plus the index into this file that the
      line-name is found. This option is accepted for compatibility, but
      does nothing in this version of sessreg.
- -t ttys-file
- This specifies an alternate file which the -x option will use to
      count the number of terminal sessions on a host. This option is accepted
      for compatibility, but does nothing in this version of
    sessreg.
- -V
- This option causes the command to print its version and exit.
- -a
- This session should be added to utmpx/wtmpx.
- -d
- This session should be deleted from utmpx/wtmpx. One of -a/-d must be
      specified.
xdm(1), utmpx(5), wtmpx(5)
Keith Packard, MIT X Consortium