Summary and analysis of common commands in Linux

Command summary

Mkdir-p (Recursive Create directory) command to create a directory Mkdirdirectorys

Ls-l (Long)-D (directory) displays the directory or the file name list (the first file in Linux belongs to the hidden file) use-A to view such files

CD switch directory hierarchy change directory CD ~ represents switch home Directory CD-Switch to the previous location of the directory

PWD View the current directory

echo Print output (printf complex output)

Printf-format and print data

Vi/vim similar to the win Notepad/emeditor Editor, Command mode (: wq:q: q! : wq!) <==> Insert mode (ESC Toggle Command mode)

w write Q quit! Mandatory

: Set Nu Display line number, DD delete the current line, yy copy the current line, p paste, line number GG positioning to the line, G Switch to the end of the file, GG to the head of the file.

Cat view file contents, can append multiple lines of text cat-n display line number

Cat>> a.txt<<eof (>> reverse re-append, input redirection (his feature is multi-line re-append, single-line words with ECHO, usually appended to the end)

[email protected] ~]# cat >> a.txt<<eof

> ASD

> Nihao

> Linux

> EOF

[email protected] ~]# cat A.txt

Asd

Nihao

Linux

TAC Invert content output

CP-APR copy file or directory-P can only copy directories to copy files to add-R

MV Move directory or rename (rename command) move (rename) file

Rm-f Force Delete files,-r recursively delete deleted files or directories-FR delete specified directories and files

Redir Delete Empty directory

Head header shows file header-N rows-number of rows, default header 10 rows

Tail-f (Track changes in a file's log) tail display file trailing-N lines-number of lines, default end 10 lines

One of the grep (filtering) core commands excludes-V "paichu" directly Filters "Xiangyaode"-ei

- e You can filter multiple strings at the same time, - I ignore case

Egrep equivalent to Grep-e

SED takes various content-N cancels the default output P=print D=delete

Alias Display settings Aliases Unalias

Which view the path where the command is located whereis,locate,find

The Find Lookup command-type (f D)-name "ddd" is searched by name-mtime by the modified time.

Tree-l Viewing the directory structure

Xargs is used to give the output of the find/ls to the back processing

Seq-s The specified delimiter, prints the number sequence echo {0..5}

Man view Help for commands and configuration files, etc.

Touch Create file or modify file timestamp

History-c (Clear All)-D line number view history

Diff Compare File content differences (compare files line byline)

Vimdiffedit, three, or fourversions of a file with vim and show difference

Useradd adding users

passwd--stdin Modify the user password, if you do not specify the user, then modify the current user password, ordinary users can only modify their own password.

Whoiam viewing the current command line end user

W View the currently logged on user

SU switches user roles, peasant uprising, overthrow emperor, attention to take on-

sudo allows a normal user to have a command that specifies the user root permission

Yum is an interactive,rpm based,package Namager. Package management tool to resolve RPM package dependencies

RPM-IVH Software Installation command RPM-IVH package name. rpm

Chkconfig View the command to set up automatic software

Netstart View network status Lntup or an

[--tcp|-t] [--udp|-u] [--listening|-1] [--all|-a] [--numeric|-n] [--program|-p]

lsof-i:p Ort view ports, list open files

Chatterchangefile attributes (-i+i)

Lsattrlist file attributes

Uname-a (View All)-R (view kernel)-m (view 32-bit or 64-bit) print System Informationca View the systems version, kernel version, etc.

Halt shut down the machine

Reboot restart

Shutdown-r Now (restart)-H now (shutdown)

Symbol:

; the delimiter for multiple commands.

/ the delimiter for the root or path

> or 1> Standard output redirection ( the data flow flows in the direction of the arrows), overwriting the original file contents

>> or 1>> Chase-weighted orientation (flow of data flow toward arrows), "End" of the original file, "Append" content

< or <0 standard input input redirection: Input redirection is used to change the input of the command, specifying the input, followed by the file name.

<< or <<0 input redirection: followed by a string to indicate "input end" or ctrl+d to end the input

{1 standard input (stdin): code 0, using < or <<. The flow of data flows. From left to right

2 standard Output (STDOUT): Code 1, using > or >>. From left to right

3 standard error Output (STDERR): Code 2, using 2> or 2>>.

Special:

2>&1 is to redirect the standard error to standard output (it can also be used >&) .

[[Email protected] ~] #date >a.txt

[[Email protected] ~] #cat a.txt

. years the Month - Day Tuesday 16:37:49 CST

[[Email protected] ~] #data >a.txt

-bash:data:commandnot found

[[Email protected] ~] #data 2>a.txt

[[Email protected] ~] #cat a.txt

-bash:data:commandnot found

}

.. Top level directory

. current directory

~ User's home directory

- last user's directory

| Pipe character Pass the output of the previous command to the last command with a pipe break to continue processing

{} with echo print sequence number sequence or alpha sequence echo {1 ... 6}

The PATH environment variable is capitalized, and all the paths contained within the environment variable can be directly knocked out to execute.

Global effective /etc/profile. Normal user ~/.bash_profile or ~/.BASHRC

Summary and analysis of common commands in Linux