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The 20 good habits to be used in Unix are: 1) create a directory tree in a single command. 2) change the path. Do not move the archive. 3) combine commands with control operators. 4) exercise caution when referencing variables. 5) Use escape

Introduction to shell and introduction to shell Models 1) DescriptionThe shell file suffix is sh, which can be understood as writing multiple commands to one file. As long as the shell file is executed, many associated operations can be performed,

This is a good habit that should be observed in the ten command line operation modes in linux. They not only make your operations faster, but also reduce the possibility of mistakes. They are 1. Use a mkdir statement to create a complete directory

BASH command and usage summary, bash usage Summary I need to write a Linux script in my recent work and use a lot of BASH commands. To avoid forgetting it later, I will write them down here one by one. It may be messy. Just take a look. If something

As already mentioned, variable names can only contain numbers, letters, and underscores, because some variables that contain other characters have special meanings, and such variables are called special variables.For example, $ represents the ID of

To interact with Linux, the script gets keyboard input results that are essential, and read can read the keyboard input characters. 1. Restricting input characters For example, after you enter 5 characters, you end up with 5 characters entered into

Michael Stutz, author of the Linux Cookbook, has summed up 10 good habits with his many years of experience in using UNIX, and personally believes that it is really useful, and is summarized below to share with you.1. Create a hierarchy directory:

I. Declaration and reference of variables in the shell[[email protected] ~]# Var1=hello[[email protected] ~]# echo $var 1hello[[email protected] ~]# echo ${var1}worldhelloworldIn the shell, a reference to a variable uses $.In the above code, $var 1

Variable names can only contain numbers, letters, and underscores, because some variables that contain other characters have special meanings, and such variables are called special variables.For example, $ represents the ID of the current shell

$ represents the ID of the current shell process, which is the PID $echo $$Run results2934List of special variables variables meaning $0 filename of the current script arguments passed to

This article is intended to review shell variable definitions, use variables, delete variables, read-only variables, variable types, special variable instancesKnowledge Reserve The variable is essentially a specified area in the

As already mentioned, variable names can only contain numbers, letters, and underscores, because some variables that contain other characters have special meanings, and such variables are called special variables.For example, $ represents the ID of

Variable Description:$$ The shell itself PID (ProcessID)$! PID of the Shell's last running background process$? End code of last Run command (return value)$-flag at a glance using the SET command$* all parameter lists. such as "$*" in the Case of ""

PHP single and double quotation marks can modify the string type of data, if the decorated string contains variables (example $name), The biggest difference is: double quotation marks will replace the value of the variable, and the single quotation

1PHP2 /******************************************3 * Soon to graduate, to find a job, see the Test bar4 *author Zhaojintao5 *blog www.zhaojintao.cn6 *email [email protected]7 ******************************************8 */ 9 Ten One

This article collects a bunch of shell scripting tricks, I said, I write a blog mainly to make some learning notes to facilitate their own review, so I will make such an article, there is nothing incomprehensible. About the origin of these

Java EE Development of various types of resources download list, the history of the most complete IT resources, personal collection summary. This is a good habit to follow in the 10 Linux system command line operation mode, they can not only make

php: Parameter passing between functions 1. Value Delivery Copy Code code as follows: function Exam ($var 1) { $var 1++; echo "in Exam:". $var 1. ""; } $var 1 = 1; echo $var 1. ""; Exam ($var 1); echo $var 1. "";

single quotes, double quotes, and escape characters in PHP http://blog.csdn.net/river131/article/details/9186203Category: PHP notes 2013-06-27 11:37 875 people read Comments (0) Favorites report escape characters PHP PHP single and double quotes

Michael Stutz, author of The Linux Cookbook, has summed up 10 good habits based on his years of UNIX experience. I personally think it is really useful. The following is a summary of this article.1. Create a hierarchical Directory: Use the-p option