NAME    [Toc]    [Back]

       utmp, wtmp - Login records

SYNOPSIS    [Toc]    [Back]

       #include <utmp.h>

DESCRIPTION    [Toc]    [Back]

       The  utmp  file records information about who is currently
       using the system.  The file is a sequence of utmp entries,
       as defined in struct utmp in the utmp.h file.

       The  utmp  structure  gives  the  name of the special file
       associated with the  user's  terminal,  the  user's  login
       name,  and  the  time of the login in the form of time(3).
       The ut_type field is the type of entry, which can  specify
       several  symbolic  constant values. The symbolic constants
       are defined in the utmp.h file.

       The wtmp file records all logins and logouts.  A null user
       name  indicates  a  logout  on the associated terminal.  A
       terminal referenced with a tilde (~)  indicates  that  the
       system  was  rebooted at the indicated time.  The adjacent
       pair of entries with terminal names referenced by a vertical
 bar (|) or a right brace (}) indicate the system-maintained
 time just before and just after a date command  has
       changed the system's time frame.

       The wtmp file is maintained by login(1) and init(8).  Neither
 of these programs creates the  file,  so,  if  it  is
       removed,  record  keeping  is  turned  off.  See ac(8) for
       information on the file.

FILES    [Toc]    [Back]

RELATED INFORMATION
       ac(8), init(8), last(8),  lastcomm(8),  login(1),  who(1),
       wtmpconvert(8).  delim off



                                                          utmp(4)