.\" @(#)wtmp.5 4.1 (Berkeley) %G%
wtmp \- user login history
file records all logins and logouts.
Its format is exactly like
a null user name indicates a logout on the associated
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
command has changed the system's idea of the time.
Neither of these programs creates the file,
so if it is removed record-keeping is turned off.
utmp(5), login(1), init(8), ac(1), who(1)