Shell

1. Shell to determine the file, whether the directory exists or has permissions2. #!/bin/sh3.4. Mypath= "/var/log/httpd/"5. myfile= "/var/log/httpd/access.log"6.7. # the-x parameter here determines whether the $mypath exists and has executable

design a script that monitors the surviving state of a remote machine (assuming IP 123.23.11.21) and sends a message to yourself when it finds an outage. Tips:1. You can use the ping command ping-c10 www.baidu.com2. The order to send the email is

Ctrl+A-JumpTo the start of the lineCtrl+B-MoveBack aCharCtrl+C-TerminateThe commandIs it the most used?Ctrl+D-DeleteFromUnder the cursorCtrl+E-Jumpto theEndof the lineCtrl+F-MoveForward aCharCtrl+K-DeleteTo EOLCtrl+L-ClearThe screenClear screen,

The shell is a command interpreter that provides interaction between the user and the operating system for a non-interactive interface that is oriented to the command line. The user enters commands at the command line, the shell interprets them, and

Trap commandBasic format: Trap command SIG1 SIG2 ... signThere are 3 types of signals that can be captured:Exit: Exits from the function, or the entire script finishesERR: When a command returns a non-0 status code, the command execution is

Pre-defined variables:Predefined variables are a class of special variables that are predefined by bash programs, and users can only use predefined variables, not create new predefined variables, or assign values directly to predefined variables.

#!/bin/SH############################### -- -- the# # author Jackluo # # email [email protected] ############################## #version_list=$ (SVN log--limit2|sed '1d'|sed '$d'|awk-F'|' '{print $}'|awk-V rs="" '{gsub ("\ n", "");p Rint}')

1.shell between the operating system and the user. Responsible for interpreting the command line2./etc/shells Record login system effectively supports Shell3./ETC/PASSWD Finally, someone who can see the user's default shell4. Directly enter the name

recently debugging a MATLAB-based program, in the occasional found a few more interesting tricks, to share with you ( probably is too rookie, did not involve this aspect, the generous house does not have the laughed at, has the help to you to please

Write Shell script:1) Editor like VI or Mcedi2) Set Execute permission for your scriptchmod permission Your-script-namechmod +x your-script-namechmod 755 your-script-name　　This would set read write execute (7) permission for the owner, for group and

As Linux small white, only learn a little bit to remember:When deploying a server, it is often necessary to view the console output as if it were local, to be able to view log output overrides on Linux, and, of course, to have the logs displayed in

Linux shell commandWhat is a shell?The Shell is the interface that connects the operating system kernel to the user.The terminal is the representation of the shell.the kernel version of Linux consists of three parts: the main version . Minor version

[[email protected] ~]# cat guess.sh #!/bin/bash#guess number game;n=$[$ random%100]while :d o    read -p  "Please input a number:   " n1    n2= ' echo  $n 1 | sed  ' s/[0-9]//g '      if [ ! -z  $n 2 ]    then         echo 

Fixed version:#!/bin/sh#check memcache process and restart if downMm_bin= "/usr/local/bin/memcached"Mm_log= "/home/xxx/memcached_check.log"mm_ports= ("11211" "11212")Mm_param= ("-d-m 20480-p 11211-u www" "-d-m 256-p 11212-u www")mm_count=${#mm_ports

Summary of this chapterVariables are a must in a very small program . The shell variable retains the string value , and a large number of operators can be ${var ...} used in , let you control the result of the variable .Shellprovides a number of

1.Shell command line writing rules:Multiple commands can be executed on a command line, but required;Long command statements can be expanded with \ on the command line2. Execute Shell Program2.1./test.sh2.2 Bash test.sh2.3 In order to compile and

1. If you judge some special usageIf [-Z $a] This indicates what happens when the value of variable A is emptyif [!-e file]; Then what happens when the file doesn't exist?if (($a ,==,!=,>=,$ $ does not exist, so n is empty;[Email protected] ~]# n= '

first, direct insertion sortStability, time complexity: preferably O (n), worst O (n^2), average O (n^2). Space complexity O (1)void Insertsort (int l[], int n) {int I, j,key;for (i = 1; i= 0 && Key two or two points insert sortFinds the insertion

Fly2015I love cracking training first class elective assignments section 6 Practice example programs. Have to repeat that sentence, have not seen this shell, the shell is a compression shell, relative to the compression shell, the encryption shell

SSH is the abbreviation for secure Shell, developed by the IETF Network Working Group, and SSH is a security protocol based on the application layer and transport layer. SSH is currently a more reliable protocol that provides security for Telnet