名字
last, lastb - 显示最近登录的用户列表
总览
last [-R] [-num] [ -n num ] [-adiox] [ -f file ] [name...] [tty...]
lastb [-R] [-num] [ -n num ] [ -f file ] [-adiox] [name...] [tty...]
描述
Last 向后检索 /var/log/wtmp 文件(也可以用 -f 选项指定被检索的文件)，并显示自这个文件创建以来所有登录（退出）系统的用户列表。在指定了用户名和终端名的情况下，last 只显示符合这些参数的记录。终端的名字可以简写，因此 last 0 等同于 last tty0.
当 last 捕捉到了SIGINT 信号 （产生于中断键,通常是 control-C）或 SIGQUIT 信号（产生于退出键，通常是 control-\）时, last 会显示它对文件已经检索了多少；在 SIGINT 信号的情况下 last 将终止运行。
每次系统重新启动时，虚用户 reboot 都会被记录到日志中。所以last reboot 会列出自日志文件创建以来的所有重新启动的日志记录。.PP Lastb 缺省上列出 /var/log/btmp 文件中的日志记录，这个文件包含有所有不良的登录企图。除此之外，等同于 last。
选项
- -num指定 last 要显示多少行。
"-n num"等同 -num.- -R不显示主机名列。
- -a在***一列显示主机名. 和下一个选项合用时很有用
- -d对于非本地的登录，Linux 不仅保存远程主机名而且保存IP地址（IP number）。这个选项可以将IP地址（IP number）转换为主机名。
- -i这个选项类似于显示远程主机 IP 地址（IP number）的 -d 选项，只不过它用数字和点符号显示IP数
- -o读取一个旧格式的 wtmp 文件 (用linux-libc5应用程序写入的).
- -x显示系统关机记录和运行级别改变的日志。
注意
wtmp 和 btmp 等文件也许找不到。只有这些文件存在时，系统才记录日志信息。这是一个本地配置的问题。 要想这些文件起作用，你可以用一条简单的命令 touch(1) 创建它们(如, touch /var/log/wtmp).
相关文件
/var/log/wtmp.br/var/log/btmp
作者
Miquel van Smoorenburg, miquels@cistron.nl."}}}
另见
shutdown(8),.BRlogin(1),.BRinit(8)
#p#
NAME
last, lastb - show listing of last logged in users
SYNOPSIS
last [-R] [-num] [ -n num ] [-adiox] [ -f file ] [ -t YYYYMMDDHHMMSS ] [name...] [tty...]
lastb [-R] [-num] [ -n num ] [ -f file ] [ -t YYYYMMDDHHMMSS ] [-adiox] [name...] [tty...]
DESCRIPTION
Last searches back through the file /var/log/wtmp (or the file designated by the -f flag) and displays a list of all users logged in (and out) since that file was created. Names of users and tty's can be given, in which case last will show only those entries matching the arguments. Names of ttys can be abbreviated, thus last 0 is the same as last tty0.
When last catches a SIGINT signal (generated by the interrupt key, usually control-C) or a SIGQUIT signal (generated by the quit key, usually control-\), last will show how far it has searched through the file; in the case of the SIGINT signal last will then terminate.
The pseudo user reboot logs in each time the system is rebooted. Thus last reboot will show a log of all reboots since the log file was created.
Lastb is the same as last, except that by default it shows a log of the file /var/log/btmp, which contains all the bad login attempts.
OPTIONS
- -num
- This is a count telling last how many lines to show.
- -n num
- The same.
- -t YYYYMMDDHHMMSS
- Display the state of logins as of the specified time. This is useful, e.g., to determine easily who was logged in at a particular time -- specify that time with -t and look for "still logged in".
- -R
- Suppresses the display of the hostname field.
- -a
- Display the hostname in the last column. Useful in combination with the next flag.
- -d
- For non-local logins, Linux stores not only the host name of the remote host but its IP number as well. This option translates the IP number back into a hostname.
- -i
- This option is like -d in that it displays the IP number of the remote host, but it displays the IP number in numbers-and-dots notation.
- -o
- Read an old-type wtmp file (written by linux-libc5 applications).
- -x
- Display the system shutdown entries and run level changes.
NOTES
The files wtmp and btmp might not be found. The system only logs information in these files if they are present. This is a local configuration issue. If you want the files to be used, they can be created with a simple touch(1) command (for example, touch /var/log/wtmp).
FILES
/var/log/wtmp
/var/log/btmp
AUTHOR
Miquel van Smoorenburg, miquels@cistron.nl
SEE ALSO
shutdown(8), login(1), init(8)
