NAME
     utmp - user information

DESCRIPTION
     This file allows one to discover information about who is
     currently using UNIX.  The file is binary; each entry is
     16(10) bytes long.  The first eight bytes contain a user's
     login name or are null if the table slot is unused.  The low
     order byte of the next word contains the last character of a
     typewriter name.  The next two words contain the user's
     login time.  The last word is unused.

FILES
     /etc/utmp

SEE ALSO
     init (VIII) and login (I), which maintain the file; who (I),
     which interprets it.

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