suse man page for lastlog

lastlog(5)							File Formats Manual							lastlog(5)

NAME
       lastlog - Login logging file

DESCRIPTION
       The log file /var/log/lastlog keeps track of the last successfull login of each user on the system. Not all programs logs this data and for
       some this is configurable.  The content of this file can be printed with the lastlog(8) command. Every entry has a fixed length,  the  file
       is indexed by numerical UID.  Each record contains the time, port and originating host that were used for the login.

       The structure of the file is

	      struct lastlog {
	      #if __WORDSIZE == 64 && defined __WORDSIZE_COMPAT32
		      int32_t ll_time;
	      #else
		      time_t  ll_time;
	      #endif
		      char    ll_line[UT_LINESIZE];
		      char    fail_host[UT_HOSTSIZE];
	      };

SEE ALSO
       faillog(5), faillog(8), lastlog(8), login.defs(5)

pam_login							   February 2004							lastlog(5)