目錄python
[root@localhost ~]# echo $SHELL /bin/bash
[root@localhost ~]# ip a 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000 link/ether 00:0c:29:ec:6b:40 brd ff:ff:ff:ff:ff:ff inet 192.168.234.129/24 brd 192.168.234.255 scope global noprefixroute ens33 valid_lft forever preferred_lft forever inet6 fe80::bce1:f5a5:d3b0:55a8/64 scope link noprefixroute valid_lft forever preferred_lft forever [root@localhost ~]# ip addr 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000 link/ether 00:0c:29:ec:6b:40 brd ff:ff:ff:ff:ff:ff inet 192.168.234.129/24 brd 192.168.234.255 scope global noprefixroute ens33 valid_lft forever preferred_lft forever inet6 fe80::bce1:f5a5:d3b0:55a8/64 scope link noprefixroute valid_lft forever preferred_lft forever
bash是linux系統的用戶界面,提供了用戶和操做系統之間的交互,它接收用戶的輸入,讓它送給操做系統執行(命令行操做)linux
[root@localhost ~]# echo $SHELL /bin/bash
[root@localhost ~]# cat /etc/shells /bin/sh /bin/bash /sbin/nologin /usr/bin/sh /usr/bin/bash /usr/sbin/nologin
echo "UseDNS no" >> /etc/ssh/sshd_config systemctl restart sshd
[root@localhost ~]# 管理員是# (命令提示符) 普通用戶時$
[root@localhost ~]# echo $PS1 [\u@\h \W]\$ \u 表明當前登陸的用戶 \h 表明當前主機的主機名 \W 表明當前的目錄 0表示默認字體,1表示加粗,4在字體下方加下劃線 5 閃爍 7 表明突出顯示 31-37 字體顏色 40-47 表示背景顏色 echo 'PS1="\[\e[1;35mm\][\u@\h \W]\\$\[\e[0m\]"' >> /etc/profile.d/ps.sh #永久生效
執行命令: 輸入命令回車shell
內部命令:shell 自帶的命令windows
外部命令:第三方提供的命令centos
查看命令的類型: typebash
[root@localhost ~]#type echo echo is a shell builtin [root@localhost ~]#type top top is /usr/bin/top
[root@localhost ~]# alias alias cp='cp -i' alias egrep='egrep --color=auto' alias fgrep='fgrep --color=auto' alias grep='grep --color=auto' alias l.='ls -d .* --color=auto' alias ll='ls -l --color=auto' alias ls='ls --color=auto' alias mv='mv -i' alias rm='rm -i' alias which='alias | /usr/bin/which --tty-only --read-alias --show-dot --show-tilde'
command [options.....] [args...]服務器
command 命令自己網絡
options:啓動或者關閉命令裏面的某些功能session
args:命令的做用體,通常狀況下是目錄或者文件,用戶名等等ssh
注意:
內部命令:
[root@localhost ~]# help command command: command [-pVv] command [arg ...] Execute a simple command or display information about commands. Runs COMMAND with ARGS suppressing shell function lookup, or display information about the specified COMMANDs. Can be used to invoke commands on disk when a function with the same name exists. Options: -p use a default value for PATH that is guaranteed to find all of the standard utilities -v print a description of COMMAND similar to the `type' builtin -V print a more verbose description of each COMMAND Exit Status: Returns exit status of COMMAND, or failure if COMMAND is not found.
Linux系統中的命令可分爲內部命令和外部命令。內部命令,又稱爲內建命令(builtin)。怎麼區份內部命令和外部命令了? 輸入man bash命令,就可查看全部的內部命令 BASH(1) General Commands Manual BASH(1) NAME bash - GNU Bourne-Again SHell SYNOPSIS bash [options] [file] COPYRIGHT Bash is Copyright (C) 1989-2011 by the Free Software Foundation, Inc. DESCRIPTION Bash is an sh-compatible command language interpreter that executes commands read from the standard input or from a file. Bash also incorporates useful features from the Korn and C shells (ksh and csh). Bash is intended to be a conformant implementation of the Shell and Utilities portion of the IEEE POSIX specification (IEEE Standard 1003.1). Bash can be configured to be POSIX-conformant by default. OPTIONS All of the single-character shell options documented in the description of the set builtin command can be used as options when the shell is invoked. In addi‐ tion, bash interprets the following options when it is invoked: -c string If the -c option is present, then commands are read from string. If there are arguments after the string, they are assigned to the posi‐ tional parameters, starting with $0. -i If the -i option is present, the shell is interactive. -l Make bash act as if it had been invoked as a login shell (see INVOCA‐ TION below). -r If the -r option is present, the shell becomes restricted (see Manual pape bash(1) line 1 (press h for help or q to quiit)
外部命令:
[root@localhost ~]#python --help usage: python [option] ... [-c cmd | -m mod | file | -] [arg] ... [] 可選項 <> 表示變化的數據 ... 表示列表 a|b|c 或者 -abc 表示-a -b -c {} 表示分組
1 Executable programs or shell commands #用戶命令 2 System calls (functions provided by the kernel) # 系統調用 3 Library calls (functions within program libraries) # 庫的調用 4 Special files (usually found in /dev) #設備文件與特殊文件 5 File formats and conventions eg /etc/passwd # 配置文件格式 6 Games #遊戲 7 Miscellaneous (including macro packages and conventions), e.g. man(7), groff(7) # 雜項 8 System administration commands (usually only for root) # 管理類的命令 9 Kernel routines [Non standard] # 內核的API 退出q 翻屏 空格 翻行 回車 man 章節 passwd
[root@localhost ~]#name=alexdsb [root@localhost ~]#echo "$name" alexdsb [root@localhost ~]#echo '$name' $name [root@localhost ~]#echo "wo shi `tty`" wo shi /dev/pts/2 [root@localhost ~]#tty /dev/pts/2 [root@localhost ~]#echo "wo shi $(tty)" wo shi /dev/pts/2
touch file{1..20} #建立20個文件 seq 0 2 10 echo file{1..20..2}
echo -e 'dadasda\ndasdasd' echo -e '\a' #播放聲音
[root@localhost ~]#whoami # 顯示當前的登陸用戶 root [root@localhost ~]#who am i #顯示當前登陸用戶的詳細信息 root pts/2 2019-08-22 15:54 (192.168.21.1) [root@localhost ~]#w 顯示全部的用戶並顯示執行的命令 16:27:54 up 5:19, 9 users, load average: 0.00, 0.01, 0.05 USER TTY FROM LOGIN@ IDLE JCPU PCPU WHAT root tty2 11:37 4:48m 0.02s 0.02s -bash wu tty3 11:39 4:48m 0.02s 0.02s -bash root :0 :0 11:30 ?xdm? 1:28 0.36s /usr/libexec/gnome-session-binary --session gnome-classi root pts/0 :0 11:35 4:43m 0.03s 0.03s bash root pts/1 192.168.21.1 12:11 4:03m 0.02s 0.02s -bash root pts/2 192.168.21.1 15:54 2.00s 0.18s 0.03s w wu pts/3 192.168.21.1 12:27 2:26 0.05s 0.05s -bash
[root@localhost ~]#date 顯示當前的時間 Thu Aug 22 16:30:06 CST 2019 Usage: date [OPTION]... [+FORMAT] or: date [-u|--utc|--universal] [MMDDhhmm[[CC]YY][.ss]] [root@localhost ~]#date 010923102018 #修改時間 Tue Jan 9 23:10:00 CST 2018 [root@localhost ~]#date Tue Jan 9 23:10:18 CST 2018 [root@localhost ~]#ntpdate time.windows.com #同步網絡服務器時間 unix元年 1970-01-01 [root@localhost ~]#date Thu Aug 22 16:35:44 CST 2019 [root@localhost ~]#date Thu Aug 22 16:35:47 CST 2019 [root@localhost ~]#date Thu Aug 22 16:35:48 CST 2019 [root@localhost ~]#date +%a Thu [root@localhost ~]#date +%A Thursday [root@localhost ~]#date +%F 2019-08-22 [root@localhost ~]#date +%H 16 [root@localhost ~]#date +%I 04 [root@localhost ~]#date +%m 08 [root@localhost ~]#date +%d 22 [root@localhost ~]#date +%M 38 [root@localhost ~]#date +%h Aug [root@localhost ~]#date +%c Thu 22 Aug 2019 04:38:42 PM CST [root@localhost ~]#date +%T 16:39:01 [root@localhost ~]#date +%y 19 [root@localhost ~]#date +%Y 2019 [root@localhost ~]#date +%Y/m/%d 2019/m/22 [root@localhost ~]#date +%Y/%m/%d 2019/08/22 [root@localhost ~]#date +%s 1566463197 [root@localhost ~]#date +%W 33
[root@localhost ~]#timedatectl Local time: Thu 2019-08-22 16:42:43 CST Universal time: Thu 2019-08-22 08:42:43 UTC RTC time: Thu 2019-08-22 08:42:43 Time zone: Asia/Shanghai (CST, +0800) NTP enabled: no NTP synchronized: no RTC in local TZ: no DST active: n/a [root@localhost ~]#timedatectl set-timezone Asia/Tokyo
[root@localhost ~]# cal August 2019 Su Mo Tu We Th Fr Sa 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
[root@localhost ~]# cal -y 2019 January February March Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa 1 2 3 4 5 1 2 1 2 6 7 8 9 10 11 12 3 4 5 6 7 8 9 3 4 5 6 7 8 9 13 14 15 16 17 18 19 10 11 12 13 14 15 16 10 11 12 13 14 15 16 20 21 22 23 24 25 26 17 18 19 20 21 22 23 17 18 19 20 21 22 23 27 28 29 30 31 24 25 26 27 28 24 25 26 27 28 29 30 31 April May June Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa 1 2 3 4 5 6 1 2 3 4 1 7 8 9 10 11 12 13 5 6 7 8 9 10 11 2 3 4 5 6 7 8 14 15 16 17 18 19 20 12 13 14 15 16 17 18 9 10 11 12 13 14 15 21 22 23 24 25 26 27 19 20 21 22 23 24 25 16 17 18 19 20 21 22 28 29 30 26 27 28 29 30 31 23 24 25 26 27 28 29 30 July August September Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa 1 2 3 4 5 6 1 2 3 1 2 3 4 5 6 7 7 8 9 10 11 12 13 4 5 6 7 8 9 10 8 9 10 11 12 13 14 14 15 16 17 18 19 20 11 12 13 14 15 16 17 15 16 17 18 19 20 21 21 22 23 24 25 26 27 18 19 20 21 22 23 24 22 23 24 25 26 27 28 28 29 30 31 25 26 27 28 29 30 31 29 30 October November December Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa 1 2 3 4 5 1 2 1 2 3 4 5 6 7 6 7 8 9 10 11 12 3 4 5 6 7 8 9 8 9 10 11 12 13 14 13 14 15 16 17 18 19 10 11 12 13 14 15 16 15 16 17 18 19 20 21 20 21 22 23 24 25 26 17 18 19 20 21 22 23 22 23 24 25 26 27 28 27 28 29 30 31 24 25 26 27 28 29 30 29 30 31
[root@localhost ~]# cal 2008 2008 January February March Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa 1 2 3 4 5 1 2 1 6 7 8 9 10 11 12 3 4 5 6 7 8 9 2 3 4 5 6 7 8 13 14 15 16 17 18 19 10 11 12 13 14 15 16 9 10 11 12 13 14 15 20 21 22 23 24 25 26 17 18 19 20 21 22 23 16 17 18 19 20 21 22 27 28 29 30 31 24 25 26 27 28 29 23 24 25 26 27 28 29 30 31 April May June Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa 1 2 3 4 5 1 2 3 1 2 3 4 5 6 7 6 7 8 9 10 11 12 4 5 6 7 8 9 10 8 9 10 11 12 13 14 13 14 15 16 17 18 19 11 12 13 14 15 16 17 15 16 17 18 19 20 21 20 21 22 23 24 25 26 18 19 20 21 22 23 24 22 23 24 25 26 27 28 27 28 29 30 25 26 27 28 29 30 31 29 30 July August September Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa 1 2 3 4 5 1 2 1 2 3 4 5 6 6 7 8 9 10 11 12 3 4 5 6 7 8 9 7 8 9 10 11 12 13 13 14 15 16 17 18 19 10 11 12 13 14 15 16 14 15 16 17 18 19 20 20 21 22 23 24 25 26 17 18 19 20 21 22 23 21 22 23 24 25 26 27 27 28 29 30 31 24 25 26 27 28 29 30 28 29 30 31 October November December Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa Su Mo Tu We Th Fr Sa 1 2 3 4 1 1 2 3 4 5 6 5 6 7 8 9 10 11 2 3 4 5 6 7 8 7 8 9 10 11 12 13 12 13 14 15 16 17 18 9 10 11 12 13 14 15 14 15 16 17 18 19 20 19 20 21 22 23 24 25 16 17 18 19 20 21 22 21 22 23 24 25 26 27 26 27 28 29 30 31 23 24 25 26 27 28 29 28 29 30 31 30