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Go back to: Linux series Shell series Awk series Process control statement Note: statement blocks in awk have no scope and are global variables. if (condition) statement [ else statement ] expr1?expr2:expr3 while (condition) statement do statement while (condition) for (expr1; expr2; expr3) statement for (var in array) statement break co ...

Catalog chmod chown chgrp umask chmod explain Command name: chmod change the permissions mode of a file Command path / bin/chmod Execute permission: all users Function Description: change file or directory permissions grammar chmod [{ugoa}{+-=}{rwx}] [File or directory] chmod [mode=421] [File or directory] -R Recursive modification ...

1, Magic number in programming In the first article of constant definition in Section II of the programming specification of Alibaba Java Development Manual: Magic value (magic number) refers to an undefined constant, while the "ID × Taobao × U" in the opposite example is called ...

Preface Preceding text Overview of ADB (I)ADB(2) ﹣ adbd ﹣ main() function code sortingADB(3) ﹣ adbd ﹣ adbd ﹣ main() function code sortingCode sorting of the host side of ADB (IV)ADB(5) sorting out the code related to the adb server on the host side First of all, we know that ADB indirectly call ...

Variables in Shell System variables Common system variables $HOME, $PWD, $SHELL, $USER, etc 2. Case practice (1) View the value of the system variable [root@hadoop100 learnshell]# echo $HOME /root (2) Display all variables in the current Shell: set [root@hadoop100 learnshell]# set BASH=/bin/bash ...

Inspection content: Understand the role of Application (primary) Familiar with class inheritance and life cycle of Application (intermediate) In depth understanding of Application initialization principle (Advanced) What is the role of Application? (first of all, it is a system component with a long ...

Catalog man whatis apropos --help info help man explain Command name:man Command English original meaning:manual Command path: /usr/bin/man Execution rights: all users Function description: Get help information grammar man [command or configuration file] Example #View help for ls command man ls Page Down with Space Page Up U ...

I have a script that automates processes that need access to password protected systems. Access the system through a command-line program that accepts the user password as a parameter. I want to prompt the user to type their password, assign it to a shell variable, and then use that variable to build the command line of the accessor (which, ...

Browser plug in Google translation (Chinese and English) Markdown Preview Plus Github Tree Click view raw to download and install Word translation qiniu upload files Seven cattle online map Vim reference vim ~/.vimrc syntax on set number set tabstop=4 set expandtab set hlsearch VSCode Set up ...

shell programming condition test Shell Conditional Judgment InitialShell branch if statementShell Loop for StatementShell branch case statementSelect List Select LoopShell loop controls continue,break,exitShell loop while statement Shell Conditional Judgment Initial [] Represents a conditional test, ...