Shell

The command line can execute multiple commands at once, in the following ways:1. Separate each command;Note: The execution of each command will not affect the execution of other commands. In other words, each command executes,However, there is no

1. In the current directory, look for the files that were accessed within 20 minutes, and display the details of the file:Find./-name ' *.log '-mmin-20-exec ls-l {} \;Note: where {} is replaced by the file name, and the colon is used to indicate

1, dirs1) Functiondisplays all records in the current directory stack (the dirs command with no parameters displays the records in the current directory stack)2) Syntax(1) format: dirs [-CLPV] [+n] [-n](2) Options-C Delete all records in the

1. Get specific information from a string of stringsRequirement 1: Get the IP profile of the native IP:menu.lst as the system mirror, and need to obtain the native IP information from the file (get information from the files)1Timeout12 default 03 4

  1). Background:During cluster deployment, consistent configuration and environment settings are required. for Virtual Machine clusters, you can copy, copy, and restore cluster machines by using images. different from physical machine clusters, if

I. Condition statements 1, If [expression] Then # Code block Fi 2, If [expression] Then # Code block Else # Code block Fi 3, If [expression] Then # Code block Else if [expression] # Replace this field with Elif [expression] Then # Code block Else #

Since HDFS is a distributed file system for data access, operations on HDFS are basic operations on the file system, such as file creation, modification, deletion, and modification permissions, folder creation, deletion, and renaming. Pair HDFS

Echo-e "\ e [1; 31 m This is red text \ e [0 m" \ E [1; 31 m set the color to red, \ e [0 m "will reset the color. Each color has a corresponding color code, resetting 0, black 30, red 31, green 32, Blue 34, Magenta 35, cyan 36, white 37 To set

I. Regular Expression description · Concept: Describe data with common attributes with a string of characters · Note: when using regular expressions for matching, be sure to use the \ transfer symbol. · Format: A. grep [Option] 'regular expression'

Some linnux commands have very powerful functions, mainly because they support many Command Options. For example, the [IP] command can be used to configure and manage IP addresses and route entries. This command can complete all the functions

Convex hull diameter Detailed description of convex hull diameter // Calculate the convex hull diameter. Input convex hull Ch. The number of vertices is N, which is arranged counterclockwise. The square of the output diameter Int rotating_calipers

Traditional if statements -- use conditional expressions as if conditionsIf [conditional expression]ThenCommandCommandCommandElseCommandCommandFiConditional expressionsFile expressionIf [-F file] If the file existsIf [-d...] If the directory

Start:The URL of svnis in excel. I copied it to txt.pdf, while VIOs only extracted the URL and saved it as url.txt.You can use VI to process url.txt, add SVN checkout, and other words to become the svn. Sh that can be run. Each row isSVN checkout.../

Part 1 simple common commands 1. Date command   2. Display calendar Cal   3. display the current directory pwd   4. Switch the current working directory By default, the main directory of a Super User is/root, while that of a common user is the same

Preface: Take notes on network-related knowledge, including IP address A/B/C classification, static address configuration/DNS configuration, and nic information viewing. *) Division of A/B/C/D network addresses IP address = network address + host

Single branch if statement If condition; then statement1 statement2fi Dual-branch if statement If judgment condition; then statement1 statement2 ...... Else statement3 statement4 ...... Fi Multi-branch if statement If condition 1; then statement1

In the shell command terminal, Ctrl + n is equivalent to the downward direction key, and Ctrl + p is equivalent to the upward direction key. You can use them or the arrow keys in the Command terminal to quickly find historical commands. This is

Time when the file is read #! /Bin/bash For file in 'ls/root' Do Stat $ file> 1.txt Sed-n "7 p" 1.txt> 2.txt Usetime = awk-F ":" '{print $2}' 2.txt Echo "time =" $ file $ usetime Done The while statement that reads each row of a file. Cat afile |

Loop Control Structure of shell script Programming Loop Control-for Loop Syntax 1 For Variable in List Do Commands Done Syntax structure 2 For Variable in List; do Commands Done This List can be a List, variable, command, etc. A for Loop provides an

I. Command Format Gawk options program file Gawk options: -F fs specifies the file delimiter used to describe the data fields in a row -F file: Specifies the file name of the reader. -V var = value defines the variables and default values used