learn unix shell scripting

1. Linux Scripting Basics1.1 Basic Introduction to grammar1.1.1 StartThe program must start with the following line (must be placed on the first line of the file):#!/bin/shThe symbolic #! is used to tell the system that the parameters behind it are the programs used to execute the file. In 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

Tags: exit USB machine $ Example des user created Linu specifiedChapter 23rd using other shellsThe bash shell is the most widely used shell in the Linux distribution. But it's not the only option, and there are other shells you can choose from.23.1 What is dash shellBaidu Encyclopedia said: Dash Shell is a Unix

How to Learn C language in UNIX/Linux, unixlinux I. Tools "To do good deeds, you must first sharpen your tools ". Programming is a very practical job. In your future studies or work, you will often deal with the following tools. The following lists the software and tools that are often used to learn C programming. 1. Operating System It is easy to

Try to make your work more efficient, write scripts, and use scripts, often with less effort. So, take some time today to learn about shell scripting.--------------ahead of the high-energy warning, this article is written slightly entertain, if you have to look uncomfortable, please go to the top right corner----------------------The

.....Directory(i) Learn the Unix Environment Advanced Programming (APUE) Standard IO(ii) Study of UNIX Environment Advanced Programming (APUE) file IO(iii) Learn about the Unix Environment Advanced Programming (APUE) files and directories(iv)

Shell Scripting Learning The shell is the command parser that converts the user-entered instruction into a program that the appropriate machine can run.The shell is a program that acts as an interface between a user and a Linux system, allowing the user to enter commands to be executed to the operating system, which c

How can shell scripting be used better? Especially in UNIX and Linux operating systems. Next, let's take a look at how to use shell script programming. Like other UNIX operating systems and Linux systems, IBM? AIX? The operating system provides several powerful tools to help

shell is different from the normal program return value that we understand, and the Shell function return value can only be a numeric value, usually to indicate success or failure of the function, 0 for success, and other values to fail. Therefore, it is inappropriate to return the function execution result with the return value of the function. If you return a string, you get an error message: "Numeric ar

use it as the first command option. The FS parameter immediately following the-F option is a regular expression or is provided as the next argument. The field separator character can also be set to be specified using the built-in variable FS. Such as:Awk-f ' \ t ' {...} ' files fs= ' [\f\v] ' filesAbove example the value set by the-F option is applied to the first filegroup, and the value specified by FS is applied to the second group. The-v option initialized must be placed before any programs

Shell: It was a major shell in earlier versions and later became a standard. Written by Stephen Bourne from Bell Labs. Each Unix-like system has at least one shell compatible with it. The program of the Bourne Shell is named "sh", which is usually put in/bin/sh. C

the default format for shell scripts written in Windows systems is DOS instead of UNIX, resulting in incorrect output results.Look at the format of the shell script and edit the shell script with VI. Then enter ": Set FF?" If the output end is "Fileformat=dos", you need to modify the format of the file// modify file f

)Redirect in-depth explanationIn general, each Unix/linux command will open three files when it is run: Standard input file (stdin): stdin file descriptor for 0,unix program reads data from stdin by default. Standard output file (stdout): StdOut file descriptor for 1,unix program defaults to stdout output data Standard error file (stderr): The st

Http://www.runoob.com/linux/linux-shell.htmlShell Pass ParametersIn addition, there are several special characters for handling parameters: parameter Handling Description $# The number of arguments passed to the script $* Displays all parameters passed to the script in a single string $$ The current process ID number for the script to run $! ID number of the last process running in the background

Shell script is similar to batch processing under Windows/dos, that is, the use of various commands pre-placed into a file, convenient one-time execution of a program file, mainly for the convenience of administrator settings or management. The advantage of scripting languages over Perl and Python is that it handles the underlying business because there are a lot of Linux commands to support, such as "Alarm

, convert uppercase characters to lowercase. option allows you to specify the characters you want to delete, and to condense the inherited characters into one.Common options:-C take Source-char-list's inverse meaning. TR the character to be converted into a character that is not listed in the source-char-list. This option is typically used in conjunction with-D or-S.-C is similar to-C, but handles characters rather than binary byte values.-D self-standard input removes the characters listed in S

Head> 3 title>Test Python Web servertitle>4 Head>5 Body>6This is a test Python Web server,b>Hello!b>7 Body>8 HTML>View CodeHistory |awk ' {cmd[$ 2]++; count++;}END {for (a in CMD) print cmd[A] "" cmd[a]/count* "%" A} ' |Grep-v "./" |Column-c3-s ""-t |Sort-nr |NL | Head-n10 This line of script can output your most commonly used 10 commands, so you can even insight into what kind of programmer you are. Do you know the code? It doesn't matter, the system learns * nix

Find a very detailed Linux shell script tutorial, in fact, not only the shell script programming, but also introduced the system of various commandsHttp://vdisk.weibo.com/s/yVBlEojGMQMpvThis book is divided into five parts, in detail the shell programming skills, a variety of UNIX commands and syntax, but also related

Learning two months of Linux, remember a lot of commands, know the role of the script, also by the script killed about half of the brain cells, and now the script is not skilled use, feel lost. Love my brain cells, hate the script, but have to say that the script is a good thing ah, it is really convenient to use, but write it really burn the head! The following summary of this week to learn the scripting s

file from line 22nd to line 33rd to the end of line 44th. Sed ' 1,21h;22h;23,33h;44g ' pass 18, move the file from line 22nd to line 33rd to the end of line 44th. Sed ' 22{h;d};23,33{h;d};44g ' pass 19, only the first word of each line is displayed. Sed-nr ' s/([^a-z]*) ([a-z]+) ([^a-z]+] (. *)/\2/p '/etc/passwd 20, print the first word and the third word of each line. Sed-nr ' s/([^a-z]*) ([a-z]+] ([^a-z]+) ([a-z]+] ([^a-z]+) ([a-z]+] (. *)/\2

The VI Editor is an editor that unix/linux system administrators must learn to use. Read a lot of information about VI, finally get this summary. First, remember the two modes of the VI Editor: 1,Command mode2, editing mode . After a unix/linux shell command or a VI command that starts with a slash (/), question mark (