Shell

In the bash shell, there are 2 main classes of Process Control commands: " condition ", " loop ". "Conditions" are: If, case, the "loop" has: for, while, until; command select is both "condition" and "loop". Either way, the condition test is

Practice Environment:(1) All servers will shut down firewalls and SELinux(2) The root password for all servers is set to AIXOCM(3) All servers are 10.0.100.* network segments and are guaranteed to communicate with other hosts(4) All servers ensure

Safety planning for Springboard machine:Back-end server--center machine, Springboard machineSpringboard machine: Used as a springboard Landing center machineCentral machine: Commonly used for distribution, used to log on to the backend serverIn the

EmbeddedLinux Bare Metal Development (16)--Shell implementation First,Shell Introduction The shell is the interface between the user and the operating system and provides the user with an interface to use the operating system.1. Graphical interface

Replace: If the expression contains special characters, the shell will replace it. For example, using a variable in double quotes is a substitution. The escape character is also a replacement#！ /bin/Basha=tenecho"Value of A is ${a} \ n"The #-e

#!/bin/sh#date:2015-12-13#filename:fang-dos.sh  #version: v1.0while truedo     #awk ' {print $} ' Access_2015-12-15.log|grep-v "^$" |sort|uniq-c >/tmp/tmp.log    netstat-an|grep est|awk-f ' [:]+ ' { Print $6} ' |sort|uniq-c >/tmp/tmp.log     exec

The shell can recognize 4 different types of cited symbols: single quote character ' double quote character ' backslash character \ anti-quote character ' 1. Single quotation mark (')# grep Susan PhonebookSusan Goldberg 403-212-4921Susan Topple 21

Environment:Ansible End:ip:192.168.100.129Hostname:node1.lansgg.comClient side:ip:192.168.100.131Hostname:v2.lansgg.comip:192.168.100.132Hostname:v3.lansgg.com[Email protected] ansible]# Pwd/etc/ansible[[email protected] ansible]# cat

If syntax:if [expression]ThenCommandselif [Expression2]ThenCommandsElseCommandsFiCase Syntax: Case string1 inSTR1)commands;;STR2)commands;;*)Commans;;EsacLoop statement for syntax: for Var in listDoCommands done  In this form, for each item in the

Shell: Can batch processing, automation to complete a series of maintenance tasks, greatly reduce the burden of administrators! The shell is a special application that acts as a "command interpreter" between the operating system kernel and the user.

Abstract: 1) The Linux shell uses let, [], (()) Three operators to manipulate shell variables for simple basic operations; 2) The Linux shell uses expr and BC two programs to achieve advanced operations; 1, basic operation of

This example of the book needs to be supported in Ubuntu's lower version of the system, and now basically does not support, want to implement it is very simple to write a script to back up and then delete.Alias has just made a replacement.Alias rm= '

If the expression contains special characters, the Shell will replace it. For example, using a variable in double quotes is a substitution, and an escape character is also a substitution.As an example: #!/bin/bash A=ten echo-

Http://wenku.baidu.com/link?url=9Q9VU54XuvlN77urP1zwOLVMMrS2EFNx4HcvFizdPl-zQy3K_ Ipd3o-mdu4sbihezumnq0blbwhusuaol_y6quvkxtgjiaem9gq9i-jb5_e Shell in the condition to determine if in the-Z to-D meaning 2011-09-05 [-a file] if the file The existence

One, Bash command processing of 12 steps; 1. Divide the command line into tokens delimited by the fixed element character set; SPACE, TAB, NEWLINE, ; , (, ),, |,& Token types include words, keywords, I/o redirects, and semicolons.2. Check the first

The meaning of shell variable $#,[email protected],$0,$1,$2 in Linux is explained:Variable Description:$$The PID of the shell itself (ProcessID)$!PID of the Shell's last running background process$?End code of the last Run command (return

3.Shell Input and output3.1.echoThe echo command can display a line of text or a variable, or output a string to a fileecho [option] string-E: Parsing escape characters-N: Carriage return is not newline, Linux system default carriage return

Reprint Address: http://www.cnblogs.com/pipelone/archive/2009/04/17/1437879.htmlExecutes. sh script in Linux, exception/bin/sh^m:bad interpreter:no such file or directory.Analysis: This is caused by different system encoding formats: the. sh file

Bash Shell Basic features three (array)One, the array definitionAn array is a contiguous number of independent memory spaces, each of which corresponds to a variable. The bash shell supports only one-dimensional arrays, but there is no limit to the

Use Shell in Linux to monitor network traffic, and use linuxshell #input the network name if [ -n "$1" ]; then eth_name=$1else eth_name="eth0"fi send_o=`ifconfig $eth_name | grep bytes | awk '{print $6}' | awk -F : '{print