Shell

First, the Logical volume label Logical Volume Label Express meaning 1. About the file and directory of the detection of Logical volume label! -F Common! Detect if "Archive" exists eg:if [-f

Suppose we define a variable as:File=/dir1/dir2/dir3/my.file.txtWe can replace each other with ${} to get different values:${file#*/}: Take out the first/its left string: dir1/dir2/dir3/my.file.txt${file##*/}: Take out the last/and left string:

There's a post on stack overflow, "What's your most controversial programming opinion?" translated into Chinese is " What do you think is the most controversial programming idea?" However, in more than 400 main huitie, as well as thousands of huitie,

String interception of Linux is useful. There are eight ways.Suppose there is a variable var=http://www.aaa.com/123.htm.1. # Intercept, delete the left character, leave the right character.echo ${var#*//}where Var is the variable name and the # is

Tag: The grep command of the Shell scripting toolgrep (abbreviated from globally search a Regular expression and Print) is a powerful text-search tool for Linux systems that can search for text using regular expressions , and print out the matching

The coffee is too much to drink. I guess I'll have no sleep tonight. Mom, Egg.The arithmetic operation of the shell. There are too many. There are many tools available to download on the Web. This article only selects the commonly used to carry on

The recent use of a partition on the line was too fast, and Nagios did not turn on the monitoring of partition usage, taking a few minutes to temporarily write a script to use first. The usage is relatively simple, directly on the code:Note: The

Shell principle Cognition:About wildcard characters in the shell *The shell expands the wildcard character before passing it to the command, such as "ls-ld/usr/include/*" first expands to "Ls-ld file-list,"View history:You can view the command

Previous note in the terminal Input shell command to achieve the LED lights and off, as a beginner, has been excited for a while, because finally has a 0 breakthrough. Manual light led always more trouble, or through the program let it go to light

Today, when running the shell script, the pin report is wrong as follows:　　　　-bash:./month_web_user_rc.sh:/bin/bash^m:bad interpreter:no such file or directoryThe cause of the problem and the solution are as follows: (excerpt from esther0401)One of

Awk:gsub Replacement NETSTAT-TNPL | Gawk ' $NF ~/\/mongod$/{gsub (/.+:/, "", $4);p rint $4} ' |sort-n to replace all $4: End with empty shell array ${#ports [@]} #得出数组长度 ${ports[@]} = ${p Orts[*]} to derive the array value ${ports[@]:8} to get the

$ () and "(anti-quote ) are used to do command substitution. Next, let's see ${} ... It's actually used for variable substitution. Shell if interpretation statements are common:[Front and rear spaces] Front Space[-D file] True if file exists and

  from the Code Farm supplement Linus and Linux, Chapter: Shell you may not know.   recently finished reading this book, feel that there are a lot of good content, this is one of the shell small dessert, bring to share with you, add some of my own

Remember that once wrote the script by the days of the cycle, the real date can be any day, like this:1start_day=$ (Date-D"$TODAY -1days"+%y%m%d);2 3end_day=$ (Date-D"$TODAY-${cycle}days"+%y%m%d);4 5 for((; $END _dayDate-D"$END _day +1days"+%y%m%d )

The Shell history record audit and monitoringHttp://netkiller.github.io/journal/shell.history.html Mr.Neo Chen(Chen Jingfeng),Netkiller, Bg7nyt China Guangdong province Shenzhen Khe Sanh Street, Longhua District, civil Administration518131+86 1311366

Linux Auto-install JDK shell scriptA: This script runs the machine, LinuxB: The machine to install the JDK, LinuxFirst, on machine a where the script is running, you can log on to the machine B where the JDK is to be installed without SSH password,

If statement:It used to be a test.Example 1: Notify the manager when the hard drive is over 80%Example 2:apache Auto-restart when closedExample 3: Multi-branch if statementExample 4: Backup etc directoryCase statement:For statement:Bulk

First, the regular expression:Metacharacters is a character used to illustrate the meaning of a character expression, in short, a character used to describe a character.The regular expression re (Regular expression) is a string of characters

The Hill sort (Shell sort) is a kind of insertion sort, which is an improvement on the direct insertion sorting algorithm. This method is also known as narrowing the incremental sort, because of the DL. The shell was named after it was introduced in

Use of shell (1) variables in Linux, linuxshell One Variable Echo $ a: output variable a. If it does not exist, a variable a is created. Unset a: Cancel variable 1.1 environment variables: Env: View descriptions of environment variables and common