Bash If

Bash (GNU bourne-again shell) is the default shell of many Linux platforms, in fact, there are many traditional Unix shell, like tcsh, CSH, Ash, BSH, Ksh, and so on, SHell script is roughly similar, When you learn a shell, the rest of the shell will soon start, and most of the time, a shell script can often be used on many kinds of shells. By learning how to use bash scripting ...

This method is urgently needed to record what time to try ^^ In Linux, you can use the crontab + php method: 1, the use of crontab-e edit the contents of regular tasks: xx: xx: xx Execute a test.php File 2, php file must be in the first line of the file, with the interpreter path (as perl do) #! / Usr / local / bin / php PHP implementation requires Apache support, she ...

How to install a custom Linux kernel Linux kernel is the heart of the http://www.aliyun.com/zixun/aggregation/13835.html ">ubuntu operating system." Ubuntu's own kernel usually contains all the drivers you need, but sometimes you want to tweak your kernel or if you need to recompile for specific reasons, this manual will help you. Like this less detailed document can actually be found in the kernel compilation Guide. Want to ...

I believe you have seen in many places "Docker based on Mamespace, Cgroups, chroot and other technologies to build containers," but have you ever wondered why the construction of containers requires these technologies? 　　Why not a simple system call? The reason is that the Linux kernel does not have the concept of "Linux container", the container is a user state concept. Docker software engineer Michael Crosby will write some blog posts and dive into Docke ...

The friendly interactive shell, just like its name, fish is a very friendly shell, highly recommended! Use the command sudo apt install fish to install it. When you are done, run the command fish to switch to fish and exit back to bash. A brief introduction to its advantages: automatic completion, syntax highlighting the automatic completion of bash is only the completion of the full command, the path, if you want to complement the full variable, parameters, etc., usually need to use complex combination ...

Today, after testing a remote AIX host in Java, it suddenly occurred to me that Hadoop was installed on Linux, but did not attempt it on AIX, and wondered if the installation of Hadoop under Aix would be different, so the process was recorded as follows: 1. 　　Install the decompression software on AIX, install Java and so on, here do not say. 2. Download the Hadoop0.21.0 version, and extract to a specific directory, where the decompression to/home/cqq/hadoop-0 ...

If you only want to see the first 5 lines of the file, you can use the Head command, such as: Head-5 passwd If you want to view the last 10 lines of a file, you can use the tail command, example: [Root@localhost software]# head-5/etc/ Passwdroot:x:0:0:root:/root:/bin/bash &http://www.aliyun.com/zixun/aggregation ...

Overview distcp (Distributed copy) is a tool for copying within and between clusters of large clusters. It uses Map/reduce to implement file distribution, error handling and recovery, and report generation. It takes the list of files and directories as input to the map task, and each task completes a copy of some of the files in the source list. Because of the use of the Map/reduce method, the tool has a special place in semantics and execution. This document provides guidance for common DISTCP operations and describes its working model. Use method Basic Use Method D ...

You can use the flexibility inherent in the command shell of Linux to create scripting languages that help you simulate DOS commands in a Linux environment. 　　 　　The specific approach is as follows. If you are an IT support expert, you like the command of Windows very much, when you first use the Linux command line, you may soon find yourself confused. The DOS commands you've been familiar with for a long time don't exist in Linux. So you will find yourself facing a terrible task: to learn and be familiar with the whole ...

This page will teach you how to design your own personalized x (graphics desktop) session by editing the shell script. Desktop environments like Gnome usually have their own session manager. These session managers allow you to set what additional programs will be loaded at startup by providing a graphical interface. However, knowing how to create an X session script allows you to have greater flexibility in defining your desktop environment, whether you use Gnome, KDE, XFCE, Openbox, or any of the less-known window managers, like Blackbox or fvw ...