NAME
     wtmp - user login history

DESCRIPTION
     This file records all logins and logouts.  Its format is
     exactly like utmp (V) except that a null user name indicates
     a logout on the associated typewriter.  Furthermore, the
     typewriter name `~' indicates that the system was rebooted
     at the indicated time; the adjacent pair of entries with
     typewriter names `|' and `}' indicate the system-maintained
     time just before and just after a date command has changed
     the system's idea of the time.

     Wtmp is maintained by login (I) and init (VIII).  Neither of
     these programs creates the file, so if it is removed
     record-keeping is turned off.  It is summarized by ac
     (VIII).

FILES
     /usr/adm/wtmp

SEE ALSO
     utmp (V), login (I), init (VIII), ac (VIII), who (I)

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