Shell

Many friends of the notebook in less than a year, the appearance of the wear is very strong, it is very regrettable. As long as a little measure, you can effectively protect the appearance of your laptop. You know, whether it is mobile phone or

First of all, the CPU is a technical work, careless operation easily damage the CPU, please be cautious, the method introduced for reference only, we must be careful in dismantling. How does the CPU shell take apart? To disassemble the CPU Shell

#!/bin/bashyum-y Install BCKenel= ' Uname-r 'Kenel= ' echo ${kenel:0:3} 'If [$ (echo "${kenel} >= 3.10" | BC) = 1];thensudo yum install-y yum-utilssudo yum-config-manager--add-repo Https://download.docker.com/linux/centos/docker-ce.reposudo yum

Reference from Linux command DaquanTo see if the shell command is a shell built-in command, use the type to determine: $ Type cdCD is a shell builtin$ Type pingPing is/bin/ping All built-in commands are as follows:ShThe

1. Write a script, implement batch add 20 users, username user1-20, password is user followed by 5 random characters2. Shell Utility case: Batch generation of random character files3. Please use at least the 两种 method to achieve! Change all of the

The security and stability of the server is the goal that every operation and maintenance want to achieve, after all, once the website traffic is big, access is high, there will be some boring people to attack, to help detect the vulnerability is

3 Kinds of TEST commands:Test EXPRESSION[EXPRESSION][[EXPRESSION]]Note: You must have a white space character before and after expressionTest type of BashNumerical test:-eq: Is it equal-ne: Whether or not to wait-ge: is greater than or equal to-le:

Move cursor shortcut keysCtrl+f move forward one characterCtrl+b Move backward one characterCTRL + A moves to the beginning of the current homeCtrl+e move to the end of the current lineAlt+f move forward one wordAlt+b Move backward One wordCtrl+l

string-to-integer type! This requirement should be common in programming languages, and it's too cumbersome in the shell. Someone asked why the conversion? The problem I encountered is that the number of parameters is $ #需要进行整型运算, while $ #取出来的却是字符串,

Writing multiplication formulas with a for loopNew script File for.sh[[email protected] shell] #vim for.sh#!/bin/bashFor ((i=1;iDoFor ((j=1;jDoLet "Sum=i*j"Echo-n "$j * $i = $sum"DoneEchoDoneExecute script[[email protected] shell] #sh for.sh1*1=11*2=

Add: Send mailOutbox: [Email protected] alex3714 custom client login account and password are: [email protected] sbalex3714Inbox: [Email protected] alex371Python failed to send mail via SMTP:Error 1:SMTPLIB. Smtpauthenticationerror: (550, B ' User

Although expr is not very noticeable in the Linux shell command, it is very large in function! So far, I personally see the biggest role is two--arithmetic and string manipulation. first say arithmetic, in the shell arithmetic not simple subtraction,

Temporary Configuration network (IP, gateway, DNS) + permanent configurationDns:vim/etc/resolv.confGateway: Route add default GW 192.168.157.254 netmask255.255.255.0Route-nIp:ifconfig Ens33 192.168.157.130/24Permanent configuration: cd/etc/sysconfig/

Write the background of this script: because more and more machines are being managed, each login machine can display the information of the corresponding machine to prevent mis-operation.At the same time, the individual working environment has many

Write the Hello World script and execute the scriptTwo methods1, ls-a view all the files2. mkdir test.sh Create a file named test.sh3, CD test.sh into test.sh this file4, Vim test.sh open vim and enter into test.sh this file5, I (insert insertion,

In the shell command terminal, CTRL + N equals the direction-down direction key, ctrl+p the direction key that corresponds to the direction.   in the command terminal through them or the arrow keys can be used to quickly find the history command.

===========================================================================if define a PATH variable in a statement the path that raised the command bug where path change occurs problem Original script file: INotify +rsync Live Sharing

For example 123456.txt content is as follows90115601,2137786735 3668490115601,2137786735 3668490118301,17751822 3489890145133,2050186877 384790145133,2050186877 384790151825,3580430507 3797490151825,3580430507 3797490188754,2987861307 2453390188754,2

Bash features multiple command executions, such as: # COMMAND1 $ (COMMAND2), and communication between Processes (IPC): # COMMAND1 | COMMAND2 ...I. Command execution structure and algorithmIn command execution, there are sequential execution

Several Methods for executing shell This section describes four methods for python to execute shell commands: 1. the OS. system () function in the OS module executes shell commands. Note: This method cannot be output by shell commands. 2. popen ()