Shell

650) this.width=650; "style=" Float:none; "title=" Image 3.png "alt=" wkiom1nnubjx4zb9aaamaxpzm1a628.jpg "src="/http S3.51cto.com/wyfs02/m00/25/e9/wkiom1nnubjx4zb9aaamaxpzm1a628.jpg "/>1, first check whether the environment variable is configured or

Instance 1: Step 1: Use VI to create a file **. Sh (this is not introduced here) #! /Bin/bash Note: This specifies the shell to explain the following command. CD/var/log # Switch the directory to/var/log (# It is the annotator in

Each line read by shell from a standard input or script is called a pipeline; it contains one or more commands ), these commands are separated by one or more pipe characters (|. In fact, there are many special symbols that can be used to

The special folder name is used to index the set to retrieve the required special folders. The following special folders are listed in the document:

1,! $ Is a special environment variable, which represents the last string of the previous command. For example, you may: You can change it: $ Mkdir mydir $ MV! $ Yourdir#$ MV mydir yourdir $ CD! $  2. ^ old ^ new Replace some strings in

What is data stream redirection? What is data stream redirection? This should be explained by the running result of the command! Generally, if you want to run a command, it will usually be like this: Figure 5.1.1 data transmission

1.Use the value assignment statement:Format:LetValue assignment expression【Tip] The Value assignment expression can be omitted as follows:((Value assignment expression))Example: Give the independent variableIAdd1Let I = I + 1Or(I = I + 1) -----------

> Array Names = (max Helen Sam Zach) Names [*] extracts all data and returns it as an element. Names [@] Retrieves all data, but returns an array, which can be used to assign values to the array. > Export Make the variables of the parent

You can execute multiple commands at a time in the command line, including the following: 1. Use between each command;SeparateNote: The execution of each command does not affect the execution of other commands. In other words, each command is

I don't have a tutorial. Let's talk about it!We get a shell. If we want to know more about it, we can't trace it in depth. There is no shortcut! You have to pay a lot of time and thinking and analysis. If you cannot do this, please give up. It is

[email protected]:~$ cat b.sh#!/bin/bashdir=`pwd`dir=$dir‘/‘for f in `ls *.png`do echo $dir$fdone Check the execution of each line of code: [email protected]:~$ bash -x b.sh++ pwd+ dir=/home/wade+ dir=/home/wade/++ ls chrome_1407299385726.png

ShellList the 10 most frequently used shellsHistory | awk '{A [$2] ++} end {for (I in a) {print a [I] "" I}' | sort-Rn | HEADHistory | awk '{A [$4] ++} end {for (I in a) {print a [$ I] & quot; i} '| sort-Rn | HEADGrep-V "#". bash_history | awk '{++

Job Management For example, after logging on to bash, we want to copy files, search data, compile data, and write vi programs! Of course, we can log on to the terminal environment of the six text interfaces again. However, can we achieve this in a

Read a file, assign each row to an array variable, and print it out in a for loop. Copy codeThe Code is as follows :#! /Bin/sh I = 1 SUM = 'sed-n' $ = 'tmp.txt '# calculates the total number of lines in the file. Echo "$ SUM" While read line

Copy codeThe Code is as follows :#! /Usr/bin/CT-f Set ipaddress [lindex $ argv 0] Set passwd [lindex $ argv 1] Set timeout 30 Spawn ssh root @ $ ipaddress # CT "yes/no" # Send "yesr" Reset CT "password :" Send "$ passwdr" CT "] *" Send

1. backup_run.sh Copy codeThe Code is as follows :#! /Bin/sh # Backup_run # Script to run the backups # Loads in a setting file for the user to change SOURCE =/home/bob/backup. defaults Check_source () { # Check_source # Can we load the file #

This small program is simple, but it is the first shell script written by the novice. It has many factors to consider, but some errors are not handled ,, #! /Bin/bash# Auth: dhh Clear Addr =/etc/yum. repos. d Mkdir $ addr/bf>/dev/null 2> & 1 Mv $

When writing a program, printing out the progress or log information properly often helps us track the running results of the program. However, printing these results or logs on the screen does not serve as a basis for future checks. This is the

Preparation: 1. Prepare the rpm file to be installed.2. Write the rpm file to the file list pkg. lst (the file name is optional)3. install. shDirectory structure|-Install. sh|-Pkg. lst|-Readme.txt|-Xxxx. rpm|-Yyyy. rpm|-Installation process: 1. Put

Many people use third-party software to build FTP and WEB servers, which means IIS is complicated and difficult to use. it may be said that IIS is not secure. This is because you do not pay attention to your security policy settings, and then others