Linxu's instructions
Usage scenario
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Basic grammar
man [command or configuration file]
NAME
ls - list directory contents
SYNOPSIS
ls [OPTION]... [FILE]...
DESCRIPTION
List information about the FILEs (the current directory by
default). Sort entries alphabetically if none of -cftuvSUX nor
--sort.
Mandatory arguments to long options are mandatory for short options
too.
-a, --all
do not ignore entries starting with .
-A, --almost-all
do not list implied . and ..
--author
with -l, print the author of each file
-b, --escape
print octal escapes for nongraphic characters
help instruction
help instruction
View help information of cd command
[root@localhost ~]# help cd
cd: cd [-L|-P] [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
The default is to follow symbolic links, as if `-L' were specified.
Exit Status:
Returns 0 if the directory is changed; non-zero otherwise.
[root@localhost ~]#
File directory class Command
pwd instruction
Displays the absolute directory of the current working directory
[root@localhost ~]# pwd /root [root@localhost ~]#
ls instruction
Displays all files and directories in the current directory, and the registration is hidden
ls -a displays all information
ls -l: displayed in list form
[root@localhost ~]# ls -l total 64 -rw-------. 1 root root 3350 Aug 9 05:52 anaconda-ks.cfg -rw-r--r--. 1 root root 41918 Aug 9 05:52 install.log -rw-r--r--. 1 root root 9154 Aug 9 05:50 install.log.syslog
cd instruction
Instructions for switching directories
parameter
cd ~: return home directory
cd... Return to the previous directory
Relative path and absolute path
Absolute path: locate from the root directory
Relative road strength: locate the required directory from the current working directory
mkdir instruction
Create directory
Common options: mkdir -p: create multi-level directory
[root@localhost home]# mkdir -p /dog/1/ [root@localhost home]# cd dog [root@localhost dog]# ls [root@localhost dog]# ll total 0 [root@localhost dog]# cd /1/ -bash: cd: /1/: No such file or directory [root@localhost dog]# cd .. [root@localhost home]# ls a dog test tiger xiaoming zwj [root@localhost home]# mkdir -p /home/animal/tiger/ [root@localhost home]# ls a animal dog test tiger xiaoming zwj [root@localhost home]# cd /animal -bash: cd: /animal: No such file or directory [root@localhost home]# cd /animal/ -bash: cd: /animal/: No such file or directory [root@localhost home]# pwd /home [root@localhost home]# cd animal/ [root@localhost animal]# cd tiger/ [root@localhost tiger]#
Delete directory
rmdir: delete directory
be careful:
If the directory is not empty, it cannot be deleted. If it is not empty, it needs to be deleted. If it is not empty, it needs to be instructed to rm -rf delete
touch command
Create an empty file
touch file name
cp instruction
cp [options] source dest
Common options- r: Copy entire folder recursively
[root@localhost home]# touch aa.txt [root@localhost home]# mkdir bbb [root@localhost home]# cp aa.txt bbb/ [root@localhost home]# cd bbb/ [root@localhost bbb]# ls aa.txt [root@localhost bbb]#
rm instruction
Remove file or directory
attribute
rm -rf: delete entire directory
rm -f: force deletion without reminder
mv instruction
Move or rename files
cat instruction
View file content cannot be modified
[root@localhost home]# cat aaa.txt sdhakjshdkj [root@localhost home]#
>Instructions and > > instructions
This file will be overwritten, and > > the contents of the file will continue to be appended
echo command
Output content to console
Common:
1. Output environment variables
[root@localhost home]# echo $PATH /usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin
2. Output simple text content
head instruction
Display the contents at the beginning of the file. The first 10 lines are displayed by default
head -n rows
Real time monitoring of text content changes
tail -f file name
In instruction
Soft connect instruction
Syntax: ln -s original file / directory connection name
Delete soft connection:
[root@localhost home]# clear [root@localhost home]# ls a aaa.txt test test2 tiger xiaoming zwj [root@localhost home]# Yes -bash: Yes: command not found [root@localhost home]# [root@localhost home]# ln -s aaa.txt b [root@localhost home]# ls a aaa.txt b test test2 tiger xiaoming zwj [root@localhost home]# head b total 24 drwx------. 26 a a 4096 Aug 9 18:57 a -rw-r--r--. 1 root root 0 Aug 9 19:11 aaa.txt drwxr-xr-x. 3 root root 4096 Aug 9 19:05 test drwx------. 4 test test 4096 Aug 9 18:54 test2 drwxr-xr-x. 2 root root 4096 Aug 9 07:53 tiger drwx------. 4 501 501 4096 Aug 9 08:14 xiaoming drwx------. 4 zwj wudang 4096 Aug 9 08:42 zwj total 28 drwx------. 26 a a 4096 Aug 9 18:57 a [root@localhost home]# rm -rf b [root@localhost home]# ls a aaa.txt test test2 tiger xiaoming zwj [root@localhost home]#
Histoy instruction
View instructions that have been executed
find instruction
find search scope options
grep directive and pipe symbol "I"
grep: filter and find. The pipeline symbol indicates that the processing result output of a command is passed to the subsequent instruction execution
Compression and decompression
gzip/gunzip
gzip: compressed file
gunzip: unzip
The original file will not be retained
zip/unzip: used for project upload
tar command
tar packing instruction