Shell

1.1. After opening the terminal, a prompt will appear, usually in the following form: [email protected]$ Or is: [email protected] # It is either simply expressed in $ or #. ($ represents a normal user, #表示超级用户 (root

A ShiftParameter shift LeftUntil [$#-eq 0]Doecho "The first parameter is: The number of arguments is: $#"ShiftDoneTwo WcThis command is used to count the number of bytes, words, and lines in the specified file. The command options have the following

#!/bin/bash# Linux Shell multifile content replace withsed# Disclaimer: # The source code is mainly the use of two (Chinese and English) with the same key-value pairs of JSON data, the HTML in the Chinese language # Automatic text substitution code.

Shuffle question: Wash a pair of poker, what good way? Can be washed evenly, and can wash fast? How efficient is the order of chaos relative to a file? On the shuffle problem, there has been a good shell solution, here another three based on the

How scripts are executedFor example, we wrote a script under/root/, named Hello.sh. So how does the call execute it? There are two ways to do this:(1) Directly through bash, as follows:Bash hello.shNote: Execute scripts with bash and do not need to

Experiment (I.)Experimental purpose: Detect system once per minute "The root partition has less than 10G of free space to send warning messages to all terminals. "Experimental requirements: Write a script and automate the script.Experimental

First, what is the bean ShellBeanShell is a scripting language that conforms fully to the Java syntax specification and has its own syntax and methods. BeanShell is a loosely typed scripting language (this is similar to JS); BeanShell is written in

The relationship between the computer and the kernel, the shell: first, the management of the entire computer hardware is actually the operating system kernel (kernel), the kernel is required to protect, so our average user can only through the

ls: View file name and directory, usage: $ ls [option]1. $ lsEnter the LS command directly, listing all files and directories in the current directory, without displaying details such as type, size, date permissions, and so on.2. $ ls-lThe-l option

WC: View File Statistics usage: $ WC filename1. $ WC fileName$ WC FileNameX Y Z/desktop/helloX: Indicates the number of rowsY: Indicates the number of wordsZ: Indicates the number of bytes/desktop/hello: Indicates file name2. $ wc-l FileName-l

Cat: View the contents of a file, connect a file, create one or more files, and redirect output to a terminal or file usage: cat [options] [file]1. $ Cat Hello.txtdisplaying content in a hello.txt text file2. $ cat-n File-N option to display the

Existing file1, file2, file3 three files, the contents are as follows$cat File1f1_1f1_2f1_3$cat File2f2_1f2_2f2_3$cat File3f3_1f3_2f3_3Write a shell script to read these three files line by row#!/bin/bashcat file1 file2 file3 |while read P do echo

Transfer from http://www.cnblogs.com/chengmo/archive/2010/10/20/1855805.htmlBefore we get to the redirect, let's take a look at the Linux file descriptor.Linux File Descriptor : Can be understood as a Linux trace open file, and the allocation of a

1) How do I pass parameters to a script?./script argumentExample : Show file name script./show.sh File1.txtcat Show.sh#!/bin/bashcat $2) How do I use parameters in a script?First parameter: $ $, second argument: $ AExample: The script will copy the

Hardware Chapter CPU-related Lscpu #查看的是cpu的统计信息. Cat/proc/cpuinfo #查看CPU信息详细信息, such as the model of each CPU, frequency, etc. Memory-related Free-m #概要查看内存情况 The unit here is

First, IntroductionShell two command execution mode:1. Interactive: single Command execution2. Batch processing: scriptShell scripts are interpreted and do not need to be compiledtips: try to use a regular user accountSecond, the InterpreterRole:

1. How Shell scripts work The Linux shell script is similar to Windows batch, but it has a lot more powerful features than Windows batch processing. The shell script is actually a stack of shell commands, with syntax such as shell operations,

Bash Script Programming:Variable: variable nameArray: Contiguous number of independent memory spaces, each memory space equivalent to a variable;Element: array name [index]Bash 4.0+Traditional arrays: Indexed as numbers, numbering starting from

The SED editor processes the input line by row, and then sends the results to the screen.-i option: Direct Action source file, source file will be modified. sed commands and options: A\ Add one or more rows after the current line

/** *  java calling DOS command for Windows  */public class RunDocInJava{     Public static void main (String[] args)  {         inputstream ins = null;        string[] cmd  = new String[] {  "cmd.exe",  "/C",  "ipconfig"  };  //  Command line