1. 命令提示符
- 作用：只有在命令提示符之后，才可以执行命令，比如，在
tail -f
- 查看命令提示符中的信息的相关命令
# 查看当前登陆用户
[root@node00 ~]# whoami
root
# 查看主机名
[root@node00 ~]# hostname
node00
# 查看当前所在的位置
[root@node00 ~]# pwd
/root 复制
- PS1环境变量
命令提示符由PS1环境变量控制
# 默认的PS1设置
[root@node00 ~]# echo $PS1
[\u@\h \W]\$ 复制
- 可以通过修改
/etc/bashrc
| PS1变量 | 含义 |
|---|---|
| \d | 代表日期，格式为weekday month day，例如"Mon Aug 1" |
| \H | 完整的主机名 |
| \h | 仅取主机的第一个名字 |
| \t | 显示24小时制的时间，格式为HH:mm:ss |
| \T | 显示12小时制的时间，格式为hh:mm:ss |
| \A | 显示24小时制的时间，格式为HH:mm |
| \u | 当前用户的名称 |
| \v | BASH版本信息 |
| \w | 显示完整的路径，家目录用"~"代替 |
| \W | 利用basename获取工作目录名称，只会列出最后一个目录 |
| \# | 执行的第几个命令 |
| \$ | 提示字符，如果是root，则提示符为#，普通用户为$ |
- 临时设置PS1变量
[root@node00 ~]# PS1='[\u@\h \w]\$ '
[root@node00 ~]# cd /etc/sysconfig/network-scripts/
# \w控制的显示全部路径已经生效了
[root@node00 /etc/sysconfig/network-scripts]# 复制
- 永久设置PS1变量
编辑
/etc/bashrc
文件
# 这是文件中默认的内容
[ "$PS1" = "\\s-\\v\\\$ " ] && PS1="[\u@\h \W]\\$ "
# 修改为你自己喜欢的格式，一个美观的PS1变量的格式如下
PS1="[\[\[\e[34;1m\]\t \[\[\e[34;1m\]\u@\[\e[0m\]\[\e[32;1m\]\h\[\e[0m\]\[\e[31;1m\] \W\[\e[0m\]]\\$ "
# 保存退出之后
source /etc/bashrc 复制
- 命令格式
# command [arg] [path]
# 名令 可选的参数选项(可选) 文件或目录(可选)
rm -rf /tmp/test.txt
# 名令和参数、参数和要操作的文件或目录之间必须有至少一个空格 复制
2. 退出登陆状态
- exit
- logout
- crtl + d
3. 终端
- 每次打开一个命令行窗口，都是开启一个新的终端，包括远程连接的窗口，使用
tty
- 终端与终端的通信
- 系统级别的命令可以自动广播到全部终端
- 使用
wall
4. Linux关机重启命令
4.1 shutdown
shutdown
命令可以安全的关闭或者重启系统，并广播关机或者重启的消息给全部的终端
# 默认在一分钟之后关机
[root@template ~]# shutdown
# 系统计划在2020-04-05 22:02:11关机,使用'shutdown -c'取消这个计划
Shutdown scheduled for Sun 2020-04-05 22:02:11 CST, use 'shutdown -c' to cancel.
# 来自root@template的广播消息,系统将在2020-04-05 22:02:11关机
# 消息将会广播给目前连接系统的所有终端
Broadcast message from root@template (Sun 2020-04-05 22:01:11 CST):
The system is going down for power-off at Sun 2020-04-05 22:02:11 CST!
# 5分钟之后关机，最大支持15min
shutdown -h 5
# 在14:00关机，也是最多支持15min的延迟
shutdown -h 14:00
# 立刻关机
shutdown -h now
# 立刻关机
shutdown -h 0
# 同理，以下为重启的时间设置
shutdown -r 5
shutdown -r 14:00
shutdown -r now
shutdown -r 0 复制
shutdown
命令的参数列表：
-r # 重启系统
-h # 关闭系统，可以再后面指定时间
-H # 关闭系统，不常用
-P # 关闭系统，不常用
-c # 取消正在执行的shutdown命令
-k # 只发送关机消息给所有终端，但并不会真正关机，极少使用 复制
4.2 halt
- 立即关机
4.3 poweroff
- 立即关机
4.4 reboot
- 立即重启
4.5 init
-
init 0
-
init 6
4.6 CentOS7的关机、重启命令
shutdown
、
reboot
、
poweroff
、
halt
在CentOS7中实际上是
systemctl
命令的参数，CentOS7还有以下系统关机重启相关的命令：
-
systemctl reboot
-
systemctl poweroff
-
systemctl halt
-
systemctl suspend
-
systemctl hibernate
-
systemctl hybrid-sleep
-
systemctl rescue
5. 查看命令帮助
5.1 man
-
man
[14:36:59 root@node00 ~]# man cp
# CP(1)
# 括号中的数字可以包括1-8
# 1 用户命令相关
# 2 系统调用相关
# 3 C的库函数相关
# 4 设备和特殊文件相关
# 5 文件的格式和规则
# 6 游戏及其他
# 7 宏、包及其他杂项
# 8 系统管理员命令和进程
CP(1) User Commands CP(1)
# 命令说明及介绍
NAME
cp - copy files and directories
# 命令的基于语法
SYNOPSIS
cp [OPTION]... [-T] SOURCE DEST
cp [OPTION]... SOURCE... DIRECTORY
cp [OPTION]... -t DIRECTORY SOURCE...
# 命令的详细描述
DESCRIPTION
Copy SOURCE to DEST, or multiple SOURCE(s) to DIRECTORY.
Mandatory arguments to long options are mandatory for short options too.
-a, --archive
same as -dR --preserve=all
--attributes-only
don't copy the file data, just the attributes
--backup[=CONTROL]
make a backup of each existing destination file
-b like --backup but does not accept an argument
--copy-contents
copy contents of special files when recursive
-d same as --no-dereference --preserve=links
-f, --force
if an existing destination file cannot be opened, remove it and try again (this option is ignored when the -n option
is also used)
-i, --interactive
prompt before overwrite (overrides a previous -n option)
-H follow command-line symbolic links in SOURCE
-l, --link
hard link files instead of copying
-L, --dereference
always follow symbolic links in SOURCE
-n, --no-clobber
do not overwrite an existing file (overrides a previous -i option)
-P, --no-dereference
never follow symbolic links in SOURCE
-p same as --preserve=mode,ownership,timestamps
--preserve[=ATTR_LIST]
preserve the specified attributes (default: mode,ownership,timestamps), if possible additional attributes: context,
links, xattr, all
-c deprecated, same as --preserve=context
--no-preserve=ATTR_LIST
don't preserve the specified attributes
--parents
use full source file name under DIRECTORY
-R, -r, --recursive
copy directories recursively
--reflink[=WHEN]
control clone/CoW copies. See below
--remove-destination
remove each existing destination file before attempting to open it (contrast with --force)
--sparse=WHEN
control creation of sparse files. See below
--strip-trailing-slashes
remove any trailing slashes from each SOURCE argument
-s, --symbolic-link
make symbolic links instead of copying
-S, --suffix=SUFFIX
override the usual backup suffix
-t, --target-directory=DIRECTORY
copy all SOURCE arguments into DIRECTORY
-T, --no-target-directory
treat DEST as a normal file
-u, --update
copy only when the SOURCE file is newer than the destination file or when the destination file is missing
-v, --verbose
explain what is being done
-x, --one-file-system
stay on this file system
-Z set SELinux security context of destination file to default type
--context[=CTX]
like -Z, or if CTX is specified then set the SELinux or SMACK security context to CTX
--help display this help and exit
--version
output version information and exit
By default, sparse SOURCE files are detected by a crude heuristic and the corresponding DEST file is made sparse as well.
That is the behavior selected by --sparse=auto. Specify --sparse=always to create a sparse DEST file whenever the SOURCE
file contains a long enough sequence of zero bytes. Use --sparse=never to inhibit creation of sparse files.
When --reflink[=always] is specified, perform a lightweight copy, where the data blocks are copied only when modified. If
this is not possible the copy fails, or if --reflink=auto is specified, fall back to a standard copy.
The backup suffix is '~', unless set with --suffix or SIMPLE_BACKUP_SUFFIX. The version control method may be selected via
the --backup option or through the VERSION_CONTROL environment variable. Here are the values:
none, off
never make backups (even if --backup is given)
numbered, t
make numbered backups
existing, nil
numbered if numbered backups exist, simple otherwise
simple, never
always make simple backups
As a special case, cp makes a backup of SOURCE when the force and backup options are given and SOURCE and DEST are the same
name for an existing, regular file.
GNU coreutils online help: <http://www.gnu.org/software/coreutils/> Report cp translation bugs to <http://translationpro‐
ject.org/team/>
# 命令的作者
AUTHOR
Written by Torbjorn Granlund, David MacKenzie, and Jim Meyering.
# 版权信息
COPYRIGHT
Copyright © 2013 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later
<http://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law.
# 命令的相关信息说明
SEE ALSO
The full documentation for cp is maintained as a Texinfo manual. If the info and cp programs are properly installed at
your site, the command
info coreutils 'cp invocation'
should give you access to the complete manual.
GNU coreutils 8.22 August 2019 CP(1)
Manual page cp(1) line 131/161 (END) (press h for help or q to quit) 复制
-
man
- Page Down：向下翻页
- Page Up：向上翻页
- Home：跳转到第一页
- End：跳转到最后一页
- /：向下查找，例如
/hello
- ?：向上查找，例如
?hello
- n,N：使用
/
?
n
N
- q：退出
man
5.2 command --help
使用
command --help
来查看该命令的帮助信息，例如
cp --help
：
[14:51:37 root@node00 ~]# cp --help
Usage: cp [OPTION]... [-T] SOURCE DEST
or: cp [OPTION]... SOURCE... DIRECTORY
or: cp [OPTION]... -t DIRECTORY SOURCE...
Copy SOURCE to DEST, or multiple SOURCE(s) to DIRECTORY.
Mandatory arguments to long options are mandatory for short options too.
-a, --archive same as -dR --preserve=all
--attributes-only don't copy the file data, just the attributes
--backup[=CONTROL] make a backup of each existing destination file
-b like --backup but does not accept an argument
--copy-contents copy contents of special files when recursive
-d same as --no-dereference --preserve=links
-f, --force if an existing destination file cannot be
opened, remove it and try again (this option
is ignored when the -n option is also used)
-i, --interactive prompt before overwrite (overrides a previous -n
option)
-H follow command-line symbolic links in SOURCE
-l, --link hard link files instead of copying
-L, --dereference always follow symbolic links in SOURCE
-n, --no-clobber do not overwrite an existing file (overrides
a previous -i option)
-P, --no-dereference never follow symbolic links in SOURCE
-p same as --preserve=mode,ownership,timestamps
--preserve[=ATTR_LIST] preserve the specified attributes (default:
mode,ownership,timestamps), if possible
additional attributes: context, links, xattr,
all
-c deprecated, same as --preserve=context
--no-preserve=ATTR_LIST don't preserve the specified attributes
--parents use full source file name under DIRECTORY
-R, -r, --recursive copy directories recursively
--reflink[=WHEN] control clone/CoW copies. See below
--remove-destination remove each existing destination file before
attempting to open it (contrast with --force)
--sparse=WHEN control creation of sparse files. See below
--strip-trailing-slashes remove any trailing slashes from each SOURCE
argument
-s, --symbolic-link make symbolic links instead of copying
-S, --suffix=SUFFIX override the usual backup suffix
-t, --target-directory=DIRECTORY copy all SOURCE arguments into DIRECTORY
-T, --no-target-directory treat DEST as a normal file
-u, --update copy only when the SOURCE file is newer
than the destination file or when the
destination file is missing
-v, --verbose explain what is being done
-x, --one-file-system stay on this file system
-Z set SELinux security context of destination
file to default type
--context[=CTX] like -Z, or if CTX is specified then set the
SELinux or SMACK security context to CTX
--help display this help and exit
--version output version information and exit
By default, sparse SOURCE files are detected by a crude heuristic and the
corresponding DEST file is made sparse as well. That is the behavior
selected by --sparse=auto. Specify --sparse=always to create a sparse DEST
file whenever the SOURCE file contains a long enough sequence of zero bytes.
Use --sparse=never to inhibit creation of sparse files.
When --reflink[=always] is specified, perform a lightweight copy, where the
data blocks are copied only when modified. If this is not possible the copy
fails, or if --reflink=auto is specified, fall back to a standard copy.
The backup suffix is '~', unless set with --suffix or SIMPLE_BACKUP_SUFFIX.
The version control method may be selected via the --backup option or through
the VERSION_CONTROL environment variable. Here are the values:
none, off never make backups (even if --backup is given)
numbered, t make numbered backups
existing, nil numbered if numbered backups exist, simple otherwise
simple, never always make simple backups
As a special case, cp makes a backup of SOURCE when the force and backup
options are given and SOURCE and DEST are the same name for an existing,
regular file.
GNU coreutils online help: <http://www.gnu.org/software/coreutils/>
For complete documentation, run: info coreutils 'cp invocation'
# 设置系统字符集之后，可以查看中文描述
[14:54:27 root@node00 ~]# LANG="zh_CN.UTF-8"
[14:55:12 root@node00 ~]# cp --help
用法：cp [选项]... [-T] 源文件 目标文件
或：cp [选项]... 源文件... 目录
或：cp [选项]... -t 目录 源文件...
Copy SOURCE to DEST, or multiple SOURCE(s) to DIRECTORY.
Mandatory arguments to long options are mandatory for short options too.
-a, --archive 等于-dR --preserve=all
--attributes-only 仅复制属性而不复制数据 --backup[=CONTROL 为每个已存在的目标文件创建备份
...... 复制
5.3 help
bash程序的内置命令无法使用
command --help
来获取帮助，需要使用
help command
：
[14:57:53 root@node00 ~]# help cd
cd: cd [-L|[-P [-e]]] [dir]
Change the shell working directory.
Change the current directory to DIR. The default DIR is the value of the
HOME shell variable.
The variable CDPATH defines the search path for the directory containing
DIR. Alternative directory names in CDPATH are separated by a colon (:).
A null directory name is the same as the current directory. If DIR begins
with a slash (/), then CDPATH is not used.
If the directory is not found, and the shell option `cdable_vars' is set,
the word is assumed to be a variable name. If that variable has a value,
its value is used for DIR.
Options:
-L force symbolic links to be followed
-P use the physical directory structure without following symbolic
links
-e if the -P option is supplied, and the current working directory
cannot be determined successfully, exit with a non-zero status
The default is to follow symbolic links, as if `-L' were specified.
Exit Status:
Returns 0 if the directory is changed, and if $PWD is set successfully when
-P is used; non-zero otherwise. 复制
5.4 info
info command
可以提供一份最详细的关于该命令的介绍，通常是用不到的。
6. Linux系统快捷键
| 快捷键 | 说明 |
|---|---|
| tab | 补全命令或者路径 |
| Ctrl + a | 光标回到命令行行首 |
| Ctrl + e | 光标回到命令行行尾 |
| Ctrl + → | 光标以单词为单位向右跳动 |
| Ctrl + ← | 光标以单词为单位向左跳动 |
| Ctrl + f | 光标向右移动一个字符 |
| Ctrl + b | 光标向左移动一个字符 |
| Ctrl + Insert | 复制选中内容 |
| Shift + Insert | 粘贴选中内容 |
| Ctrl + k | 剪切光标处到行尾的内容 |
| Ctrl + u | 剪切光标处到行首的内容 |
| Ctrl + w | 剪切光标前的一个单词 |
| Ctrl + y | 粘贴Ctrl + k、Ctrl + u、Ctrl + w剪切的内容 |
| Ctrl + c | 终止正在执行的前台任务或者删除整行 |
| Ctrl + h | 删除光标所在处的前一个字符，同Backspace |
| Ctrl + d | 删除光标所在处的后一个字符，同Delete |
| Ctrl + d | 当命令行无字符的时候，退出当前终端 |
| Ctrl + r | 搜索执行过的命令 |
| Ctrl + g | 从搜索历史命令的UI中退出 |
| Esc + . | 获取上一条命令使用空格分隔后的最后一部分 |
| Ctrl + l | 清除屏幕内容 |
| Ctrl + s | 锁定终端 |
| Ctrl + q | 解锁终端 |
| Ctrl + z | 暂停执行在终端运行任务 |
| !! | 执行上一条命令 |
| !pw | 执行最近以pw开头的命令 |
| !pw:p | 打印最近以pw开头的命令，但不执行 |
| !num | 执行历史命令列表中第num条命令 |
| !$ | 同Esc + . |
| Esc + b | 移动到当前单词的开头 |
| Esc + f | 移动到当前单词的结尾 |
| Esc + t | 颠倒光标所在处及其相邻单词的位置 |