Shell

Condition test(a) Concept: to determine the specific conditions to determine how to perform the operation, when the condition is set, the return value of the test statement is 0, otherwise, the other value, meaning if the echo $? The value is 0,

There are a number of commands in Linux that can be divided into 10 categories (see [1]): 1) file management; 2) document editing; 3) file transfer; 4) Disk Management; 5) disk maintenance; 6) network communication; 7) system management; 8) system

grep commandgrep Example:[OPTIONS] PATTERN [FILE ...][Email protected]:~# grep ' root '/etc/passwd root:x:0:0:root:/root:/bin/bash [email protected]:~# grep "$USER"/ ETC/PASSWD Root:x:0:0:root:/root:/bin/bash [email protected]:~# grep ' whoami '/etc/

Ctrl + A cursor moves to the beginning of the lineCtrl + E cursor moves to end of lineCtrl + R Search in the history commandCtrl + L Clear ScreenCtrl + U Clear the cursor to the beginning of the characterCtrl + K Clears the character of the cursor

Input and output in the shellStandard input: KeyboardStandard output: Terminal displayThe >> append is a newline appendEcho- n do not trailing line breaks-e enable escape function to interpret backslashes-e disables the escape function that

Recently need to do a distributed architecture of the site, is currently in the debugging phase, each time the boot to start a lot of tools, such as Zookeeper, ACTIVEMQ, Redis, Nginx and so on, take pains.Search the Internet on the Mac how to set up

If you want to find common commands, please click on the imageThe instructions in the shell script, in the uncertain case, do not arbitrarily use nohup, otherwise it may have disastrous consequences, such as-memory explosionShell random function

#!/bin/shFor1 () {For I in 1 2 3 4 5 6Doecho "$i"Done}For1#!/bin/shFor2 () {For i in {1..10}Doecho "$i"Done}For2#!/bin/shFor3 () {Sum=0#int =1For i in {1..100..2}DoLet "Sum+=i"Doneecho "Sum is $sum"}For3#!/bin/shFor4 () {Sum=0For I in $ (SEQ 1 2 100)

There are two directories A, B, two folders directory of some files are the same name, but the suffix is different, I want to a folder and B folder with the same file name of the files covered to B, and delete the name of B and different suffix file,

With "'"""todayis" ' date ' preceded by a character, followed by ' date ' Represents the Execute Date command. PDATE=""'date'is Date" Expr " is used to calculate the result of a=9b=tenvar1= $a +$becho $var 1 output is "9 +10"expr" is used

5.1 Printenv View Global variables Bash New shell Set Global variables and localvariables Export Test Local→global, so it can be

Shell scripts that perform fast and easy to understand code. In the process of writing shell code, it is often used to read the file contents. Notation One:----------------------------------------------------------------------------#!/bin/bash while

Please put the following stringstu494e222fstu495Bedf3stu49692236stu49749b91Switch to the following form:stu494=e222fStu495=bedf3stu496=92236Stu497=49b91Question 2:Echo I am Oldboy training, please put the output of each character to the order,

1#!/bin/Bash2prefix=192.168. the3num=14 while["$num"-lt"255"]; Do5 Echo-en"Pinging ${prefix}.${num} ..."6 Ping-c1-w1-t5 ${prefix}.${num} >/dev/NULL 2>&17 if["$?"-eq"0"]; Then8 Echo "OK"&&Echo"${prefix}.${num}" >>Ok.txt9 ElseTen Echo "Failed"&

Writing a script today meets a strange thing.Variable A is definedIf [-a $a];then echo "exists"; else echo "not exists"; fiResult output:ExistsIt's a blind moment, but it's going to change.If [-a "$a"]Of course, a here is a script input parameters,

1. Exclude portions of files from disk usage statisticsDu--exclude "*.iso" dir2. Find the maximum of 10 files in a specified directoryFind-type f-exec du-k {} \ |sort-nrk 1 |head-n 103. List the maximum 10 commands for the current systemCat.

The first thing to know is how to play color ball: 6 red balls (1~33) and a Blue ball (1~16) to choose a so-called 6+1To generate 6 random numbers between 1~33 and cannot be equal, this is key if you use traditional judging methods (the first with

#!/bin/bash############################### #FileName: Backuplogtimer.SH#Function: Scheduled backup log file #version:0.1#Authon: xueya#date:2014.06. -############################### #获取当前路径path=`pwd`Echo "current1 path: ${path}"#循环执行 while[[1-eq1 ]]

Analysis: Randomly generate 10 numbers? Generate a random number, here with the random function, I define the generated 10 numbers as an array of arrays, the initial value of the definition max is array[0] use for loop to compare with each element's

What is a shell?The shell itself is a C language program, it is the user use Unix/linux Bridge, most of the user's work is done through the shellThe shell has two ways of executing commands:Interactive (Interactive): Explains the execution of a user'