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1. Set the environment variable histsize so that it can save 10,000 command history.Vim/etc/profile changed histsize=1000 to histsize=100002. Why does setting PS1 (ps1= "[\[email protected]\h \w]\$") show a different result than we expected, and how

Reprint: http://blog.csdn.net/ronliu/article/details/6446251The use of function pointer hooks in Linux makes it difficult to read code. For example, if you want to know the invocation path of a function, you can only look at the code with a tool

1. Single quotation mark (')grep403-212-4921212-234-2343If we're looking for Susan Goldberg and can't use the grep Susan Goldberg Phonebook command directly, GREP will treat Goldberg and phonebook as files that need to be searchedgrep ' Susan Gold '

First, the basics of learning Shell scripts" Special symbols in theLinux shell "1. * : Represents 0 or more characters or numbers.Test can have no characters, or multiple characters, or it can be matched.2.? : represents only one arbitrary

The company's wireless environment uses the MAC address authentication method, the MAC address is bound to the radius of the users configuration file, the registered MAC address as the user name and password. In order to manage these MAC addresses

First, understand the computer hardware components:Von. Neumann architecture defines the computer has the arithmetic, the controller, the memory, the input device, the output device five major parts, also has one principle is: must be the binary

1. Display the default shell of root, fedora or User1 user on the current system;650) this.width=650; "src=" Http://s1.51cto.com/wyfs02/M00/86/D6/wKiom1fMzN2TL7unAAASBVeKqHA424.png "style=" float: none; "title=" 1.png "alt="

1) Use if, case, readExample 1:#!/bin/bash#读取终端输入的字符Read-p "Please input a number:" NN1= ' echo $n |sed ' s/[0-9]//g '#使用if语句进行判断if [!-Z $n 1]Thenecho "Please input a number."Exit 1elif [$n-lt 0] | | [$n-GT 100]Thenecho "The number Ranger is

1. Set the environment variable histsize so that it can save 10,000 command history.   vim/etc/profile   change histsize=1000 to histsize=10000 2. Why do I set PS1 (ps1= "[\[email protected]\h \w]\$")    display the results to be different from

String-related operations are often involved in the shell batch process. There are a lot of command statements, such as: awk,sed can do string various operations. In fact, the shell built a series of operating symbols, you can achieve similar

First, Tomcat introduction Tomcat is a core project in the Jakarta Project of the Apache Software Foundation (Apache Software Foundation), developed jointly by Apache, Sun and other companies and individuals. With Sun's involvement and support, the

The following script backs up all the source files to be edited into the/bak directory, and all path locations remain unchanged, such as Vii/etc/hosts, and the/etc/hosts is copied to/bak/etc/hosts. # CAT/SH/VII #!/usr/bin/bash #判断源文件是否存在, exist

Prepare an article First, firewall configuration CentOS 7.x defaults to use firewall as a firewall, here to iptables firewall. 1. Close firewall: Systemctl Stop Firewalld.service #停止firewall

Upload the Tengine compressed package tengine-2.1.0.tar.gz to the server via SSH.Upload to/opt path Decompression tengine-2.1.0.tar.gzTAR-ZXVF tengine-2.1.0.tar.gz Access to the Tengine directoryCD tengine-2.1.0 Installation of Tengine

1.2.1 Echo's quote questionFor the use of ECHO, note that the special case of single and double quotes is the point. To print "Hello world!" As an example.Echo Hello world!Hello world!Echo ' Hello world! 'Hello world!Echo " Hello world! "

One day to receive the telecommunications network Supervisor email notification, the content is a website is * * *, there is a link to display "xxx" information. command to fix it immediately.Resolution process:1, view the server, found the server

The requirement for batch processing is that the randomly displayed number (6,7,8,9,10,11,12,14,15,16,17) is one of the Note: There is no 13 in the The following two code, the first error, the second is successful, but their difference is only the

Prepare the article:CentOS 7.0 System installation Configuration Diagram tutorialHttp://www.jb51.net/os/188487.html First, configure the firewall, open 80 ports, 3306 ports CentOS 7.0 uses firewall as a firewall by default, and this is iptables

1. First introduces WordPress's two powerful plug-ins: (1) Count per day is a very powerful number of visitors statistics plug-ins, can be counted daily, yesterday, weekly, monthly and so on the number of visitors (based on IP statistics),

Applicable system: Linux (Redhat, Centos,debian,ubuntu) * Linux Server data disk is not partitioned and formatted, you can follow the following steps to partition and format the operation. The following operation will divide