Lastlog

lastlog is a program available on most Linux distributions. It formats and prints the contents of the last login log file, codice_1 (which is a usually a very sparse file), including the login name, port, and last login date and time. It is similar in functionality to the BSD program last, also included in linux distributions; however, last parses a different binary database file (codice_2 and codice_3). 
Usage.
Lastlog prints its output in column format with login-name, port, and last-login-time of each and every user on the system mentioned in that order. The users are sorted by default according to the order in codice_4 However, it can also be used to modify the records kept in codice_1.
$ lastlog
Username Port From Latest
root **Never logged in**
user tty3 Sun Jan 14 16:29:24 +0130 2019