UTMPX(5)                    BSD File Formats Manual                   UTMPX(5)

NAME
     utmpx -- user accounting database

SYNOPSIS
     #include <utmpx.h>

DESCRIPTION
     In contrast to utmp and wtmp, the extended databases in utmpx and wtmpx
     reserve more space for logging hostnames, and also information on a
     process' ID, termination signal and exit status.

     The <utmpx.h> header defines the structures and functions for logging
     user.  Currently logged in users are tracked in /var/run/utmpx.  The
     interface to the utmpx file is described in endutxent(3).  The file is
     not automatically created if they do not exist; it must be created manu-
     ally.

     Traditionally, separate files would be used to store the running log of
     the logins and logouts (wtmpx), and the last login of each user
     (lastlogx).  With the availability of the Apple system log facility
     asl(3), these separate files can be replace with log entries, which are
     automatically generated when utmpx entries are written.  The API to
     access the logins and logouts is described in endutxent_wtmp(3) while the
     last login info is accessible with getlastlogx(3).

     For compatibility, changes to utmpx are reflected in utmp(3) (in the
     utmp, wtmp and lastlog files), but not the other way around.

FILES
     /var/run/utmpx  The utmpx file.

SEE ALSO
     asl(3), endutxent(3), endutxent_wtmp(3), getlastlogx(3), utmp(5)

BSD                            January 31, 2007                            BSD