bash amplifier

Bash should be the most popular shell script interpreter in Linux. (another shell is called Dash. I hate it too much .), As long as you work on Linux and want to enjoy yourself, you should be familiar with the most basic bash programming, because it will bring enough happiness to your work. This article will summarize some basic bash programming knowledge that I

Create scriptFunctional testing is a key part of software development-and bash loaded into Linux can help you easily complete functional testing. In this article, Angel Rivera describes how to use bash shell scripts to execute Linux applications by running commands. Program Function test. Because this script depends on the return code of the command line, you cannot apply this method to GUI applications.

1. Execute bash shell:(1) Go to the directory where the shell script is located: CD/root/tmp and execute./test. Sh. (2) execute shell script:/root/tmp/test. Sh in absolute path mode. (3) run the script CD/root/tmp bash test. Sh, sh test. Sh, or bash/root/tmp/test. Sh directly using bash or sh. (4) Execute./root/tmp/tes

] '#abc# Hello World# Hi WorldPractice:Pass a user name parameter to the script to determine if the user's user name is consistent with the group name of their base group, and the results are displayed.#!/bin/bash#if! ID $ >/dev/null; Thenecho "No such user"Exit 10Fiif [' id-n u $ ' = = ' id-n-G $ ']; Thenecho "The Same"Elseecho "Not the same"Fi=================================================================Exercise: Write a scriptPass a parameter (s

Bash string processing (against Java)-2. String Representation (String constant) In JavaYou know!Use single quotes to indicate character constants: 'C'Double quotation marks are used to indicate a String constant: "hello world"Java character escape\ U ???? Four-digit decimal Unicode Character\??? Three octal characters\ N newline (\ u000a) (Insert a newline in the text at this point .)\ T horizontal tab (\ u0009) (Insert a tab in the text at this poin

September 25, foreign exposure of a "destruction level" bash vulnerability, hackers can use this vulnerability to remotely execute arbitrary commands, complete control of the target system! the vulnerability is cve-2014-6271, mainly in bash version 1.14-4.3, and affected systems include: Red Hat Enterprise Linux (versions 4-7), Fedora distribution, CentOS ( Versions 5-7), Ubuntu 10.04 lts,12.04lts and 14.04

Bash An arbitrary code run vulnerability exists in the environment variable: "A CGI request can cause remote code to run, causing the server to be compromised." Serious harm . and the official release patch was also bypassed " ,"Vulnerability Impact":1) Bash affected version number: 3.0 ~ 4.3, the bash version number less than 3.0 may also be affected.2) Intrus

Linux security vulnerability exposure Bash is more serious than heartbleed September 25 message: a Linux security vulnerability that is more serious than "heartbleed" was found, although no attack by this vulnerability has been found, but a lower operating threshold than "heartbleed" makes it more risky than the former. Bash is a software used to control Linux computer command prompts. Dan gido, CEO of Tr

The following two tips to enhance Bash functions: one is to improve Bash command history management, and the other is to enable Bash to have a more intelligent automatic completion feature. The implementation process is not complex. You only need to modify the default configuration of Bash. Improve

BASH built-in Variables(1). BASHFunction: complete bash path. The default value is/bin/bash.(2). BASH_ENVPurpose: applicable only in non-interactive mode. When executing a shell script, the system first checks whether the variable has been specified to startScript. If it is specified, run the specified STARTUP script first.(3). BASH_VERSIONRole:

Recently write C # from Linux up and down to Windows. It feels a great difference. The biggest change is---a variety of GUI tools ah ... Everywhere, a variety of search menus. Not used!! Miss BSH's Flexibility AH ~ ~ ~Why to use GitGit is the most popular version manager of the moment. A lot of benefits, but the most important thing is actually a little Without always accessing the server, everyone has an entire warehouse PS: Git is probably the boss's favorite, we can not even go

Bash shortcut commands are stored in Bashshell. Note the following shortcut keys to greatly improve the efficiency of your command line operations. Edit command Ctrl + a: move to the beginning of the command line Ctrl + e: move to the end of the command line Ctrl + f: forward by character (right) Ctrl + B: by pressing the bash shortcut key command in Bash shell,

When you use some commands (such as ls and git), you just need to easily traverse all directories and files, and then search for them, finally, we found a "magic" wildcard "" ** "(two asterisks). After setting the Bash globstar option, ** we can match any current directory (including subdirectories) and the files. Therefore, I learned about the globstar option. When globstar is not set, ** the wildcard function is the same as *. After globstar is set,

One of the most exciting news for developers this year at Microsoft Build 2016 is that Linux bash natively runs on Windows, and for non-developers, it may not know what this means, and for developers, it means Windows makes up for the Mac OS terminal of the short board, you can run your familiar Linux Bash,python,perl, using some Linux under the library ... Instead of having to install a Cygwin or install a

Bash string processing (compared with Java)-3. assign values to the (string) Variable In JavaSimple assignmentS = "Hello ";Assignment of multiple variables at a timeS1 = s2 = "Same ";Assign a value to an integer (convert an integer to a string)Int I = 1234;S = String. valueOf (I );Or s = "" + I;In BashValue assignment (=)The value assignment operation is in the form of VAR = STRINGRemember: there cannot be spaces on both sides of the equal sign!Advanc

Bash Script Programming:If statement, Bash-n, Bash-xCONDITION:Bash command:The execution status result of the command;Success: TrueFailure: flaseThe meaning of success or failure: Depending on the command used;Single branch:if CONDITION; ThenIf-trueFiDual Branch:if CONDITION; ThenIf-trueElseIf-falseFiMulti-branch:if CONDITION1; ThenIf-trueElif CONDITION2; ThenIf-

We know that the management of the entire computer hardware is actually the kernel of the operating system (kernel), and the kernel is generally required to protect, so we generally users can only through the shell to communicate with the kernel, let the kernel do what we want to do the work. So how many shells does the system have available? Why are we using the shell? --we have to communicate our input commands to the kernel through the "shell" so that the kernel can control the hardware to wo

Bash Script Programming:???? Scripting: Interpreter interpretation execution; first of all have to clear up some trivial knowledge points, I try to do what I learned to help friends comb Programming Environment: (I will be in the next chapter, graphic examples three combinations way to take everyone to study together)???????????? Process Control statements;???????????????? sequential execution;???????????? Cyclic execution;

I. OverviewIn the previous chapter, we had an example of a script that detects if an IP address is online, but there is a problem, in the process of running, no matter Ctrl+c how to stop, and no egg, or continue to run, until the last IP address ping can not be stopped, just the current ping operation is finished, the next The ping operation will run, but if you press the shortcut key continuously, there is always a signal caught, but only by the script of the current process to be able to stop,

The shell in Linux is basically bash by default, and here are some tips I've summed up. Background Run Program() Use a child shell, for example (CD.. /.. /commlib/; Make$ () command substitution, and ' the function is the sameExamples of Use:For example, you want to use the awk script in a shell scriptAwk-f /abc/{print $;}Eof)$ (()) to perform an integer calculation $ ((66/2))if (arithmetic operation))if [[String operations]]Alias defines a command al