基础命令

Linux系统的命令通常都是如下所示的格式：

命令名称 [命名参数] [命令对象]

1. 获取登录信息 - w / who / last。 [root@izwz97tbgo9lkabnat2lo8z ~]# w 23:31:16 up 12:16, 2 users, load average: 0.00, 0.01, 0.05 USER TTY FROM LOGIN@ IDLE JCPU PCPU WHAT root pts/0 182.139.66.250 23:03 4.00s 0.02s 0.00s w jackfrue pts/1 182.139.66.250 23:26 3:56 0.00s 0.00s -bash [root@izwz97tbgo9lkabnat2lo8z ~]# who root pts/0 2018-04-12 23:03 (182.139.66.250) jackfrued pts/1 2018-04-12 23:26 (182.139.66.250) [root@izwz97tbgo9lkabnat2lo8z ~]# who am i root pts/0 2018-04-12 23:03 (182.139.66.250)
2. 查看自己使用的Shell - ps。 Shell也被称为“壳”，它是用户与内核交流的翻译官，简单的说就是人与计算机交互的接口。目前很多Linux系统默认的Shell都是bash（Bourne Again SHell），因为它可以使用Tab键进行命令补全、可以保存历史命令、可以方便的配置环境变量以及执行批处理操作等。 [root@izwz97tbgo9lkabnat2lo8z ~]# ps PID TTY TIME CMD 3531 pts/0 00:00:00 bash 3553 pts/0 00:00:00 ps
3. 查看命令的说明 - whatis。 [root@izwz97tbgo9lkabnat2lo8z ~]# whatis ps ps (1) - report a snapshot of the current processes. [root@izwz97tbgo9lkabnat2lo8z ~]# whatis python python (1) - an interpreted, interactive, object-oriented programming language
4. 查看命令的位置 - which / whereis。 [root@izwz97tbgo9lkabnat2lo8z ~]# whereis ps ps: /usr/bin/ps /usr/share/man/man1/ps.1.gz [root@izwz97tbgo9lkabnat2lo8z ~]# whereis python python: /usr/bin/python /usr/bin/python2.7 /usr/lib/python2.7 /usr/lib64/python2.7 /etc/python /usr/include/python2.7 /usr/share/man/man1/python.1.gz [root@izwz97tbgo9lkabnat2lo8z ~]# which ps /usr/bin/ps [root@izwz97tbgo9lkabnat2lo8z ~]# which python /usr/bin/python
5. 查看帮助文档 - man / info / apropos。 [root@izwz97tbgo9lkabnat2lo8z ~]# ps --help Usage: ps [options] Try 'ps --help <simple|list|output|threads|misc|all>' or 'ps --help <s|l|o|t|m|a>' for additional help text. For more details see ps(1). [root@izwz97tbgo9lkabnat2lo8z ~]# man ps PS(1) User Commands PS(1) NAME ps - report a snapshot of the current processes. SYNOPSIS ps [options] DESCRIPTION ... [root@izwz97tbgo9lkabnat2lo8z ~]# info ps ...
6. 切换用户 - su。 [root@izwz97tbgo9lkabnat2lo8z ~]# su hellokitty [hellokitty@izwz97tbgo9lkabnat2lo8z root]$
7. 以管理员身份执行命令 - sudo。 [jackfrued@izwz97tbgo9lkabnat2lo8z ~]$ ls /root ls: cannot open directory /root: Permission denied [jackfrued@izwz97tbgo9lkabnat2lo8z ~]$ sudo ls /root [sudo] password for jackfrued: calendar.py code error.txt hehe hello.c index.html myconf result.txt 说明：如果希望用户能够以管理员身份执行命令，用户必须在sudoers（/etc/sudoers）名单中。
8. 登入登出相关 - logout / exit / adduser / userdel / passwd / ssh。 [root@izwz97tbgo9lkabnat2lo8z ~]# adduser jackfrued [root@izwz97tbgo9lkabnat2lo8z ~]# passwd jackfrued Changing password for user jackfrued. New password: Retype new password: passwd: all authentication tokens updated successfully. [root@izwz97tbgo9lkabnat2lo8z ~]# ssh hellokitty@1.2.3.4 hellokitty@1.2.3.4's password: Last login: Thu Apr 12 23:05:32 2018 from 10.12.14.16 [hellokitty@izwz97tbgo9lkabnat2lo8z ~]$ logout Connection to 1.2.3.4 closed. [root@izwz97tbgo9lkabnat2lo8z ~]#
9. 查看系统和主机名 - uname / hostname。 [root@izwz97tbgo9lkabnat2lo8z ~]# uname Linux [root@izwz97tbgo9lkabnat2lo8z ~]# hostname izwz97tbgo9lkabnat2lo8z [root@iZwz97tbgo9lkabnat2lo8Z ~]# cat /etc/centos-release CentOS Linux release 7.4.1708 (Core)
10. 重启和关机 - reboot / init 6 / shutdown / init 0。
11. 查看历史命令 - history。