LOGIN(3) NetBSD Library Functions Manual LOGIN(3)
login, logout, logwtmp -- login utility functions
System Utilities Library (libutil, -lutil)
#include <util.h> void login(struct utmp *ut); int logout(const char *line); void logwtmp(const char *line, const char *name, const char *host);
The login(), logout(), and logwtmp() functions operate on the database of current users in /var/run/utmp and on the logfile /var/log/wtmp of logins and logouts. The login() function updates the /var/run/utmp and /var/log/wtmp files with user information contained in ut. The logout() function removes the entry from /var/run/utmp corresponding to the device line. The logwtmp() function adds an entry to /var/log/wtmp. Since login() will add the appropriate entry for /var/log/wtmp during a login, logwtmp() is usually used for logouts.
logout() returns non-zero if it was able to find and delete an entry for line, and zero if there is no entry for line in /var/run/utmp.
/dev/* /etc/ttys /var/run/utmp /var/log/wtmp
utmp(5) NetBSD 9.0 December 14, 1995 NetBSD 9.0
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