bourne shell programming

12 15 : 57 Bashbug 4.7. Switch to the new version of Bash to view the current version [[email protected] bin]#./echo4.3. - (3)-release 4.8. Using the new version of the shell From the above command, the current bash version is 4.3.30. This indicates that the new version of Bash has been compiled and installed successfully. However, the new shell is not yet available to

Getting started with SHELL Programming amp; Oslash; Shell Basics amp; Oslash; Process Control Syntax amp; Oslash; common commands amp; Oslash; sample presentation amp; Oslash; tip} solve the problem that cannot be solved on the interface} faster command line interface} manage bsh (BourneShell)} ksh (KornShell)} csh. getting started with

Article title: BourneShell and shell programming (2 ). Linux is a technology channel of the IT lab in China. Includes basic categories such as desktop applications, Linux system management, kernel research, embedded systems, and open source. Copyright: This article is a handout of the LINUX elective course of Dalian University of Technology. You are welcome to repost it, but this document is prohibited from

I said, the shell is my conventional weapons, although not yet proficient, but I love the shell of the language, under Linux mixed, always write a script. Programmers have genes, there is a preference for programming languages, you let me write C code, I will feel very cool, there will be difficulties, there will be painful groping and learning, but I am willing

variables (1) $? 0 for success, not 0 for failure [ [email protected]~]# Date May 01, 2018 Tuesday 18:58:42 CST [ [email protected]~]# echo $? 0 [ [email protected]~]# RM/ RM: Cannot delete "/": is a directory [ [email protected]~]# echo $? 1 In the enterprise scenario, the use of the $? Return value is as follows: ① to determine whether a program, such as a command, script, or function is successfully executed ② call Exit N in the script, will return this number to $?. ③ in the function, the n

Linux study NOTE 4: What is Shell programming? To put it simply, shell is a command parser that parses the command you entered to the system for "listening", that is, execution. There are many shell types, including Bourne shell (

http://c.biancheng.net/cpp/shell/ what the shell is. is a command line interpreter, it provides a user with a Linux kernel to send a request to run the program's interface system-level programs, users can start with the shell, hang, stop or even write some programs or a powerful to become a language, easy to write, easy to debug, flexibility strong. The

menufruit.sh nginx.sh piliangxiugai1.sh piliangxiugai2.sh piliangxiugai3.sh suijiwnjian.sh sum1-100.sh test uptime.sh usage.sh user.sh while1.sh while2.sh while3.sh while4.sh while.sh zhuajiu.sh [[emailprotected] jiaobenlianxi]# cat array03.sh array=( $(ls) ) for((i=0;i 4.Shell Array Knowledge Summary (1) Definition: Static array: array= (1 2 3) space separated Dynamic array: array= ($ (LS)) Assigning a v

this example we use/BIN/SH to execute the program. When you edit a good script, you must also make it executable if you want to execute the script. To make the script executable: Run chmod +x filename so you can use./filename to run 1.2 Notes In shell programming, comments are expressed in sentences that begin with # until the end of the line. We sincerely recommend that you use annotations in your pr

Standard input/output (read echo) of shell programming learning notes and shell learning notes 09:32:07 Input read: Purpose: Read a row from the standard input, or read a row from the file descriptor FD (file descriptor) and divide it into fields. Usage:Read [-ers] [-a array] [-d separator] [-I buffer text] [-n read characters] [-N read characters] [-p prompt]

Common commands and statements for Shell programming (SCRIPT) and Common commands for shellSome common Shell programming (SCRIPT) commands and statements can meet general requirements.Command Parameters received: Number of parameters: $ # Parameter value: Command itself: $0 first parameter: $1 second parameter: $2

From the programmer's point of view, the shell itself is a program written in C language, from the user's point of view, the shell is the user and the Linux operating system communication Bridge. The user can either enter command execution or use shell scripting to do more complicated operations. In the increasingly perfect Linux GUI today, in the field of system

ArrayBash supports one-dimensional arrays, does not support multidimensional arrays, and does not limit the size of arrays1.3.1 defining ArraysArray_name={1 2 3 4}or array_name={1234}Each component of an array is defined individually:Array_name[0]=1array_name[0]=21.3.2 reading an arrayValue=${array_name[0]}use @ or * to get all the elements in the arrayValue=${array_name[*]}Value=${array_name[@]}1.3.3 Gets the length of the arraynum=${#Array_name [@]} gets the number of array elementslength=${#

#!/bin/bash. Hellofunset"now going to thefuction Hello" hello# here will output the message:. /"back from thefunction Hello"6.6. function return Status valueExample 1:#!/bin/bashfunction Hello () { "Hello, today is ' date '" return 0 now going to thefunction Hellohello# next to output the return status value, with $? represents echo $? "back from thefunction Hello"Example 2: #!/bin/bashfunction Hello () {echo hello, today is ' date ' " return 0 }echo " now going to the functio

Shell programming learning method: shell reading files by Line Method 1 :----------------------------------------------------------------------------#! /Bin/bash while read linedo echo $ linedone

$catdowonload_image.sh#!/bin/bash######################################### #图片下载器 # #script_name:dowonload_image.sh # #author:weixiaoxinwriteby2017-09-20 ##########################################functionget_second_ Level_url () { #declare -aurl_arrayua= "mozilla/5.0 (WindowsNT 6.2;NBSP;WOW64) AppleWebKit/535.24 (Khtml,likegecko) Chrome/19.0.1055.1 safari/535.24 "curl-s-otmp.html-H" user-agent: $UA "$1 u= ' cattmp.html|grep-e-o "/html/63/[0-9]+\.html\" target=\ "_blank\" > This article is from

1.bash supports one-dimensional arrays (multidimensional arrays are not supported) and does not qualify the size of the array(1) define an array:Array_name= (value0 value1 value2 value3)OrArray_name= (Value0Value1value2Value3)or individually defined:Array_name[0]=value0Array_name[1]=value1Array_name[n]=valuen(2) Read array: ${array name [subscript]}Use the @ symbol to get all the elements in the array: Echo ${array_name[@]}(3) Get the length of the array#取得数组元素的个数length=${#array_name [@]}#或者Leng

to redirect stdout and stderr to file after merging, you can write:2>12>1(3) If you want both stdin and stdout to be redirected, you can write:Command A special redirect in 6.Here Document:shell to redirect input to an interactive shell script or program#它的基本的形式如下:: delimiter documentdelimiter! Content (document) between the #它的作用是将两个 delimiter is passed as input to command(1) At the end of the delimiter must be shelf write, the front cannot have

Linux System-shell programming-several shell scriptsone kill the userkilluser.sh#!/bin/sh# The script to kill login userUser_name= "$"/bin/ps aux | /bin/grep $user _name | /bin/awk ' {print $} ' >/tmp/temp.pidKill_id= ' Cat/tmp/temp.pid 'For PID in kill_iddo/bin/kill-9 $PID 2>/dev/nullDonetwo adding users in bulkuseradd.sh#/bin/shecho "Input name"Read nameecho "

redirected file descriptor number in front of the load > operator. Because the file descriptor for the standard error output is 2, use the 2> operator. This method is useful when you need to discard the error message and prevent it from appearing on the screen.PipelineYou can use the pipe operator | To connect to a process, unlike MS-DOS, where the process of connecting through a pipeline can run at the same time, and can be reconciled automatically as the data flow passes between them. For exa