bourne shell programming

Shell Introduction Shell is simply a command parser that converts user-input commands into programs that can be executed by corresponding machines. A Shell script is a text file (batch processing) that contains a series of command sequences ). When you run this script file, the command sequence contained in the file will be executed. HelloWorld The first line of

/*************************************** ******************************* Author: Samson* Date: 08/01/2013 **************************************** ****************************/ BASH Shell script programming learning summary: Variable:(1) environment variables: can be modified;(2) internal variables: provided by the system and cannot be modified;$ #: Get the number of parameters$? : ShellProgramReturn

frequently and do not need to be used when interacting )This method of assignment, which is followed by the argument directly behind the command, is then used by the system to refer to the first parameter.The fourth method is to use the output of the command to assign a value ( This method of assignment can directly process the data generated by the previous command )In a shell program, you can use the output of a command as a variable, but you'll ne

In the first two articles, we have mastered some of the basic syntax of the shell, the use of variables, and the operation of basic data types. So this time we will learn the shell's structured commands, which are conditional selection statements and looping statements in our other programming languages.However, when you learn shell-structured commands, we will f

One: Program concept? Program: Algorithm + data structure? data: Is the core of the programData structure: The type and organization of the information in the computer? algorithm: How data is processedProgram Programming Style:Program: command-centric, data-serving instructionObject type: Data-centric, instruction serves dataAdvanced Programming Languages:Compiled: High-level language--compilers--machine co

The use of conditional expressions in shell programming If conditionThenCommandElseCommandFi, don't forget this ending. If statement forgets the end fiTest.sh:line 14:syntax error:unexpected End of fi Three conditional expressions of IF IfCommandThenIfFunctionThen Command executed successfully, equal to return 0 (such as grep, find a match)Execution failed

Linux programming: Use PHP as a Shell script-general Linux technology-Linux programming and kernel information. For details, see the following. We all know that PHP is a very good dynamic web page development language (fast speed, short development cycle ......). However, only a few people realize that PHP can also be a good language for writing

Shell login mode, shell arithmetic operation, Shell logic operation, shell condition test, Shell selection statementShell programming in the first line indicates the path of the shell t

interface with BASHBASH provides a small statement format that allows the program to quickly design a menu of user interaction choices for a character interface that is implemented by the SELECT statement, with the syntax of the SELECT statement:Select Var in ; Do. Here is an example of using a For loop:#!/bin/bashFor day in Sun Mon Tue Wed Thu Fri SatDoEcho $dayDone# If the list is contained in a pair of double quotes, it is considered an elementFor day in "Sun Mon Tue Wed Thu

: Shell internal system variable random generates an integer number between 0~32767)Code:#!/bin/bashRead-p "Please input a number between 0 and:" xtemp=$ ((random%100))While [$x-ne$temp]Doecho "fail! Try it again! "If [$x-gt $temp];thenRead-p "Please input anumber smaller:" xElseRead-p "Please input anumber larger:" XFiDoneIf [$x-eq $temp];thenecho "Congratulations!"Fi：Summary: This experiment took a long time to complete it, unfortunately, did not co

1. Unix Shell functions A shell is a program that manages processes and runs programs. All the common shells have 3 main functions: (1) running the program; (2) Managing inputs and outputs (3) Programmable The shell is also a programming language with variable and process control. 2. UNIX Process Model A program is a

\$ $i $Done(2)#!/bin/bashfunction NL () {While read XDoecho "$x"Done}If [$#-le 1];thenecho "Error"ElseFn=$1While ["$"] [-F "$FN $"]DoNL ShiftDoneFi(3)#!/bin/bashFor file in *.c;doMV $file/home/huxingheng/cfileDoneLs-s/home/huxingheng/cfile(4)#!/bin/bashEcho-n "Please input a string:"Read Strecho $str | Cut-c $1-$2(5)#!/bin/bashRead-p "Please input a number between 0 and:" xtemp=$ ((random%100))While [$x-ne $temp]Doecho "fail! Try it again! "If [$x-gt $temp];thenRead-p "Please input a number sm

Shell Authoring Steps:1. Scripting Vim first.sh2. Write the complete test script Bash-n first.sh3. Granting permission chmod +x first.sh4. Execute the script./first.shPS Shell Script Learning first need to understand Linux, system commands and general structure familiar, able to skilled operating system and build common services to provide services, to better learn shel