Shell

There are several ways to see what shell you are currently using, and the easiest way is to use the shell's special parameters. First, a special parameter named "$$" represents the PID of the shell instance that you are currently running. This

Certificate Generation method in Apache+mod_sslThe certificate request is generated first: The code is as follows Copy Code #openssl req-new > SERVER.CSR After you follow the prompts to enter the relevant

Core code You can try these small functions when you encounter a system with a date command that does not give you power. #日期转天数 function Date2days {echo "$*" | awk ' {z=int (14-$2)/12); y=$1+4800-z; J=int ((153*m+2)/5) +$3+y*365+int (

Shell scripts can have a very large impact when they run an exception. This article describes some of the techniques that make bash scripts robust. Using Set-u How many times did the script crash because there was no initialization of the

Question Description: How do you deal with command-line options such as Tail-n Access.log in a Linux shell? In bash, command line arguments can be handled in three ways, each with its own scenario. 1, direct processing, in turn to the $1,$2,..., $n,

The variable is a string, and we assign a value. The assigned value can be a number, text, file name, device, or any other type of data. A variable is a pointer that does not exceed the actual data. Shell, you can create, assign, and delete

What is a shell script. First, it is a script and cannot be used as a formal programming language. Because it's running in the shell of Linux, it's called a shell script. To be blunt, a shell script is a collection of commands. For example, I want

Shell Script Introduction Shell is a scripting language Aming_linux (public number) blog.lishiming.net (blog) You can use logical judgments, loops, and other syntax Functions can be custom-defined The shell is a collection of system

I. Shell special symbol, Cut command* Any character[Email protected] ~]# Ls/tmp/*.txt/tmp/1.txt/tmp/2.txt/tmp/q.txt[Email protected] ~]#？ Any one character[Email protected] ~]# Mkdir/tmp/test1[Email protected] ~]# Touch/tmp/test1[Email protected] ~]#

Reprinted from: http://dos2unix.cn/link/4801. Standard input stdin file descriptor is 0, standard output stdout file descriptor is 1, standard error stderr file descriptor is 22./dev/null empty equipment, equivalent to garbage bin3. REDIRECT Symbol:>

The knowledge points in this article are related to conditional testing of shell scripts.Often in shell scripts we need to do a variety of conditional judgments, such as testing whether a file exists, whether it is a file or directory, whetherhas

Recently has been studying the shell script this piece, just idle down to the bottom of their own better information on some of the examples, the following is the bird in my brother's private dishes inside the regular expression inside the

Transfer from http://c.biancheng.net/cpp/view/2739.htmlAs already mentioned, variable names can only contain numbers, letters, and underscores, because some variables that contain other characters have special meanings, and such variables are called

In daily work, a lot of things to deal with the computer often, especially high frequency use of some professional software, or play some keyboard streaming nature of the game, you should be familiar with the commonly used shortcut keys, so play not

SSH is a toolkit to replace Telnet, FTP, and R commands, mainly to solve the problem of password transmission on the Internet. For system security and user's own rights, it is necessary to promote SSH. SSH is the abbreviated form of the English

Reprint Please specify source: http://blog.csdn.net/hellomxj1/Function: Realize the conversion of WiFi STA and AP function on Linux systemAchieve results: 1, add wifi password account Add_wifi_account; 2, wifi two mode to start the script

We all know that zabbix is a very powerful monitoring tool. Our company is also using zabbix to monitor the status of all websites. A recent requirement is that we need to generate a report that includes the time nodes and corresponding response

The following content is based on the Linux bash Environment There are many ways to run shell scripts in Unix. Suppose there is a script that can be run called test. sh. You can add the script file name, source test. sh (= .. /test. sh two .), you

Convert other hexadecimal values to hexadecimal values Octal to decimal: [Chengmo @ centos5 ~] $ (Num = 0123 ));[Chengmo @ centos5 ~] $ Echo $ num;83 [Chengmo @ centos5 ~] $ (Num = 8 #123 ));[Chengmo @ centos5 ~] $ Echo $ num;83 (Expression), (

Execute shell commands in the program to automatically obtain all online IP addresses and open ports in the LAN (Linux)Preface The question is a bit long. It is actually the following: first, let the Shell command be executed in the program, and