linux scripting basics

Linux entry basics: Linux expansion permissions default permissions each terminal has an umask attribute to determine the default permissions for new files and folders umask are represented by digital permissions, for example, the default permission for the 022 directory is: the default permission for the 777-umask file is: 666-umask. For common users, the defaul

Linux basics-initialization and service of Unit 10 system, linux InitializationUnit 10 system initialization and service Linux boot sequenceLinux boot sequenceBOIS initialization and Boot LoaderWhat is BIOS?GRUB program and grub. conf fileWhat is grub?Grub configuration file grub. confKernel initialization and init Ini

practical practice, batch of hundreds of server management4, the Enterprise Automation tool puppet use scene, realizes constructs the enterprise operation and maintenance Automation platform architecture5. Full explanation of Git version control, script automation management, git branch merging, git server Setup6. In-depth presentation of shell-based scripting enterprise advanced usage and common implementation shell automation management7, Python ba

...) ...;; EsacExample#!/bin/Bash Case " $" inch"1") Echo 1;;"2") Echo " Both";;*) Echo "your input is $";;EsacCycleWhile expression while Do ... Donefor-expression for inch Do ... DoneBoth of these expressions are relatively simple, and there is nothing special to say. I found some differences between the different systems. I found that red Hat can use the following expressions, but Debian is not. I don't know whether the system version or the system itself is different. for (i=0;i

--help //ls--helphelp //helplsman // Man lsinfo //info lsSecond, the Linux system command　Ps-af//List all Processes Ps-efNetstat-anop//list all network processesNano 1.txt //put the Nano 1.txt in the backgroundJobs//View current task processfg%1//put process number 1th in front of the foreground .bg%1//put it in the backgroundKill [-9] PID//kill Process, [9] Optional: Strong killWC 1.txt//Word statistics for 1.txt content, separated by inv

associated to the same inode number, so the two files represent the same file, and the reference count is 2. The inode for the Symbol_link file is different from Test.file because Symbol_link is a standalone file, but it is a connection file to Test.file, and you can observe that the Symbol_link file length is 9 bytes. is actually test.file the file's filename length.Finally, explain the number of connections to the directory. Each time a new empty directory is created, the number of connection

I. Introduction to Linux Shell1. Shell overviewThe shell is an interface that the user interacts with the kernel, and the most popular shell is now called the Bash shellThe shell is a programming language The Shell is a scripting language, so you have to have an interpreter to execute the scripts.The common shell scripting interpreters on Unix/

# type COMWORun commandCommand format:Comwo "Options ..." "Arglments ..."Options: One or some of the features used to enable or disable commandsShort options:-C, for example:-l,-hMultiple segment options can be ordered using: For example-l-h, can write-LH;Long options:--word, e.g.--long,--human-readableParameters: The Action object of the commandProviding data to the order;File system/root文件有两类数据： 元数据：metadata（名字，大小等其他信息） 数据：data1.文件名严格区分大小写2.文件名可使用处/以外的任意字符，不建议使用特殊字符 /：根目录，路径分割

popular Web server-side software due to its widespread use across platforms and security.BSD (Berkeley software distribution, Berkeley Software suite) is a UNIX derivative system, and BSD today is not specifically a BSD derivative version, but a branch of Unix-like operating system.Package ManagerRPM;RPM Package Manager, although the file format ranked Redhat logo, but its original design concept is open, now includes OpenLinux, Rhel,fedora,s,u,s,e, and Turbo

, and each memory area is associated with an array that manages the physical pages that belong to that memory area, and is represented by the struct page struct for each physical page.3, Memory domain watermarkThe memory watermark is represented by the pages_min,pages_high,pages_low in the struct zone struct, if the free page is more than Pages_high, the state of the memory domain is ideal, and the number of memory pages is less than Pages_low. The kernel begins to swap the page out to the hard

.jpg "style=" float: none; "title=" Qq20150216215850.png "alt=" Wkiol1th-agcqnhgaaedcl6qslo226.jpg "/>#centos6.5 You need to press ESC at startup to stay in the grub interface.#grub界面也可以按下c来进入command模式, not recommended, too many things to enter too hard to rememberRescue modeSingle-player mode can do a lot of maintenance action, but if you encounter system crashes, grub and other system-level errors we should respond to, the answer is to insert the system CD into the rescue mode.Personal Underst

1 shell overviewThe shell is a command interpreter that provides the user with an interface system-level program that sends a request to the Linux kernel to run the program. The user can start, suspend, stop, or even write some programs with the shell.The shell is a powerful programming language that is easy to write, easy to debug, and highly flexible. The shell is a scripting language that interprets exec

tasksc) Try to avoid capturing user interfaces (laying the groundwork for scripting and automating certain functions)d) The configuration file is saved in plain text format (the system configuration work can be done with a text editor)3.7 How to get the release versionA) http://mirrors.aliyun.comb) http://mirrors.sohu.comc) http://mirrors.163.com3.8 TerminalThe terminal is the device that the user must use to interact with the host.The terminal is di

Linux operating system basics, linux operating system Basic Principles of Linux: 1. It is composed of a single small program with a single purpose; it is combined to complete complex tasks; 2. Everything is a file; 3. Avoid capturing user interfaces as much as possible; (Avoid interacting with users as much as possible