linux command line and shell scripting bible

One way is to useCatand anti-quotePS: Anti-quotes play the role of command substitution in Linux. Command substitution refers to the ability of the shell to interpolate the standard output of a command anywhere on a command line.The input format is as follows:20151207[email protected]. com20151225155581558905678As followsThe internal field delimiter (Internal field Separator, IFS) is an important concept in

distinguish between different kinds of devices, while the secondary device number is used to differentiate multiple devices of the same type.The Linux kernel uses a virtual file system (SYSTEM,VFS) as an interface for interacting with each file system. This provides a standard interface for any type of file system communication within Linux. When each file system is mounted and used, the VFS will slow down

Learn Linux, starting with the commandThe graphical interface just makes simple things simpler graphical interface can quickly handle simple things, such as opening/closing a file Then, as transaction complexity increases, the graphical interface is cumbersome to manipulate For example, insert a picture in Word: Toolbar--insert--picture--Browse directory--OK This feature is not really complicated, but the whole process, click at least 4 times and t

= 0;i = 1; does {total + = $i; i++} while (total Gawk ' {total =0;-(i = 1;i Chapter 23rd using other shellsYou can try to learn to use zsh and support modularity.24th. Writing a simple script utilitySlightly25th. Create DATABASE, Web, and e-mail related scriptsThe side that writes the script to MySQL is available:MySQL mytest-u test Show tables;SELECT * FROM Employees where salary > 40000;Eofecho "This is a text message." | mail-s "Subject" [email protected]-b [email protected]-C [email protec

"Linux Command Line and shell script programming Daquan" sed advanced multi-line command sed Editor contains three commands that can be used to process multi-line text 1.N: Add the next line in the data stream to create multiple r

Create functions in Linux Command Line and shell script ProgrammingBASIC script function creation function 1. use the function keyword, followed by the function name [plain] function name {commands} 2. the function name is followed by an empty parentheses, indicating that a function is being defined [plain] name () {commands}. If the names of the two functions ar

Chapter 25th: Using E-mailLinuxE-mail in Linux, the E-mail process is generally divided into three functions: MailTransferAgent (MTA) mailDeliveryAgent (MDA ( Chapter 2: Use e-mail Linux E-mail Basics E-mail in Linux In Linux, the E-mail process is generally divided into three functions: Mail Transfer Agent (MTA) Mai

This article is one of the book notes in Chapter 6 "learning the bash shell" 3rd edition "command-line options and typed varilables, but we will not limit this article. In Linux commands, parameters such as [-Option] are often included. There may be 0 or more options in the command line. We learned the location paramet

", as4. It is also possible to add two commands together, adding the character "HEAD", "TAIL" to each line of Test.file, and the command: sed '/./{s/^/head/;s/$/tail/} ' test.fileIn fact, the above is OK, spend too much time yesterday, mainly because the file is processed by MySQL from the database extracted from the results of the guide, others gave me after I directly deal with, too brain remnants =-I have been a little doubt the result is wrong, th

Early knowledge of sed and gawk in Linux Command Line and shell script ProgrammingThe sed editor of the Text Processing editor can process data in a data stream based on commands that are input to the command line or stored in the Command text file. It reads a row each time, matches the data with the provided editor co

-N: Add line numbers to all lines -B: Add line numbers to lines with text only -S: Compress multiple blank rows into a single blank line -T: Hide tabs More commands The more command implements the text content, but stops after each page of data is displayed Command op