updwtmp(3) Library Functions Manual updwtmp(3) updwtmp, logwtmp - wtmp (libutil -lutil) #include void updwtmp(const char *wtmp_path, const struct utmp *ut); void logwtmp(const char *line, const char *user, const char *host); updwtmp() utmp ut wtmp. logwtmp() utmp line user host . updwtmp() wtmp. /var/log/wtmp attributes(7). +------+------------------------------------+--------------------------+ || | | +------+------------------------------------+--------------------------+ |updwtmp()| | MT-Unsafe sig:ALRM timer | |logwtmp()| | | +------+------------------------------------+--------------------------+ "utmpx" ( getutxent(3)) glibc ( glibc 2.1): #define _GNU_SOURCE /* feature_test_macros(7) */ #include void updwtmpx (const char *wtmpx_path, const struct utmpx *utx); updwtmp() utmpx . . Solaris NetBSD. getutxent(3) wtmp(5) 3 . . : . 6.18 8 2026 updwtmp(3)