#define UT_NAMESIZE     16
#define UT_LINESIZE     8
#define UT_HOSTSIZE     16

struct utmp {
        char    ut_line[UT_LINESIZE];   /* Terminal line name */
        char    ut_name[UT_NAMESIZE];   /* User's login name */
        char    ut_host[UT_HOSTSIZE];   /* Host user came from */
        time_t  ut_time;                /* When user logged in */
};