Shell

1, consider the following requirements, in the main shell execution command, enter the other command, the input after, want to as the input of the command, instead of the main shell input, how to do?2, use 3. The EOF here is just a delimiter and can

#!/bin/bash while:do neterror=$ (/bin/netstat-a | GREP-CW "close_wait") echo "Get TCP netstate ' LISTEN ' num ber cuccessful! " echo "Neterror" $neterror if [$neterror-gt "]; then echo" too much net Error,system would reboot

1.4adding environment variables using functions1.4.1Introductionenvironment variables are typically used to store path lists, which are used to search for executables, library files, and so on. For example:$PATH,$ld_library_path, and they usually

Use Whil for if to print a prime number less than 100#!/bin/bash#author Alvin#version 1.0.0#test for 1-100 Zhishua=2While [$a-le 100];DoZ=1for ((j = 2; $j If [$ ($a% $j))-eq 0];thenZ=0BreakFiDoneIf [$z-eq 1];thenEcho-ne $a "\ T"FiLet A+=1Done2 3 5 7

If flow control:Conditional judgment statements in the shell are similar to other programming languages.If you need to know what the criteria are, you can get help with man testCommon formatsFormat Oneif condition; ThenStatementFiFormat Twoif

For loop:Used in the shell for looping. Similar to for in other programming languages, but somewhat different. The For loop is the most common syntax structure in bash.Common format Format OneFor variableDoStatementDoneFormat TwoFor variable in

#!/bin/bash## 1, check whether the current user's identity has permissions# 2, check if there is a Yum source, if there is no need to create a Yum source configuration file# 3, install DHCP, if already installed, we can first remove and then install,

The first step:SSH Password-free login "with public key, private key"Step Two:#!/bin/bash while read server; Do "[email protected]" 2 >& 1 "s/^/$ Server:/" &donewait./bunsan2.sh Free Note: While read server considers the input as a

Tag: megacli shell awk raid 1. cat megacli.sh #!/bin/bash#--------------------------------------------------   #Created : 2015-05-22#author:jimmygong#mail:[email protected] #Function: #Version: 1.0#------------------------------- -------------------

1, log structure/opt/online/{123com,abccom}/log/online[1-9]/[a-z]2, variable description # Whether to turn on the compression function (0: OFF, 1: on; If the compression function is turned off, the Compressdayn is not valid) Needcompress=1 Delete 14

Linux operating system can be divided into shell and kernel two parts, kernel is the kernel, provides the core functions of the operating system. The shell is the shell, which is connected to the kernel (kernel) and the user. This means that the

1. CommentsIf you use bash, then in the script file header comment: #/bin/bash2, the script file with the Read and execute permissions, you can use the./shell.sh to execute, you can also use the SH shell.sh way to execute directly, SH is the soft

1. View versionCat/etc/debian_version7.82, look at the memory (my side is 256MB memory swap divided by 4G)Free-mTotal used free shared buffers CachedMEM:231 124 106 0 8 79-/+ buffers/cache:36 194swap:3814 0 38143. Using stress to simulate the

$0: The current script has a file name of $num:num 1-based number,$ $ is the first argument, and $ is the second argument, and ${is thetenth argument $#: The number of arguments passed in the script $* : All positional parameters (as a single string)

Next look at some special variables$? : Receives the return status code of the previous command, so that you know whether the previous command was successful,If the previous command succeeds, the return status code is 0, and if the previous command

#/bin/Bashhint () {Read-P"Press Enter Tocontiune:"}check_a () {PS-ef |grepCxiang|awk '{for (i=1;i'Text1//use grep and awk to filter the process into Text1. sed '/^.*/s///g'Text1 >text3//delete Text1 in front of empty row in Text3grep-VWF Text3 Text2/

The feature of this series of blogs is--give the results of each orderOriginally wanted to write a good process, get a picture of what, but think online analysis too much, are better, so these blog even if it is a summary of their own it.#include

Linux learning-advanced shell script programming (2) first recognized by sed, gawk, and sedgawk Citation: Sometimes we need to automatically process text in text files without pulling out a fully armed interactive text editor. In this case, it is

Linux learning-advanced shell script programming (I) Functions and shell script Programming Citation:When writing shell scripts, you will find that the same code or functions are used in many places. It doesn't matter if it's a small piece of code.

Several methods of shell script executionYou can execute shell scripts in the following ways: 1. The relative path method must be cd to the script path first. [Root @ banking tmp] # cd/tmp [root @ banking tmp] #./ceshi. sh script executed