Getting Started with BASH Linux/Unix

What is the Bash Shell?The GNU Bourne-Again SHell (BASH) incorporates features from the C Shell (csh) and the Korn Shell (ksh) and conforms to the POSTIX 2 shell specifications. It provides a Command Line Interface (CLI) for working on *nix systems and is the most common shell used on Linux systems. Useful bash features will be the subject of the rest of this document.Bash's Configuration FilesBecause what I want to say here has already been written I will quote the section entitled "Files used by Bash" from freeunix.dyndns.org's "Customizing your Bash environment"In your home directory, 3 files have a special meaning to Bash, allowing you to set up your environment automatically when you log in and when you invoke another Bash shell, and allow you to execute commands when you log out.These...

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Next Tutorial .htaccess

IntroductionIn the last part I introduced you to .htaccess and some of its useful features. In this part I will show you how to use the .htaccess file to implement some of these.Stop A Directory Index From Being ShownSometimes, for one reason or another, you will have no index file in your directory. This will, of course, mean that if someone types the directory name into their browser, a full listing of all the files in that directory will be shown. This could be a security risk for your site.To prevent against this (without creating lots of new 'index' files, you can enter a command into your .htaccess file to stop the directory list from being shown:Options -Indexes Deny/Allow Certian IP AddressesIn some situations, you may want to only allow people with specific IP addresses to access...

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.htaccess Tutorial

IntroductionIn this tutorial you will find out about the .htaccess file and the power it has to improve your website. Although .htaccess is only a file, it can change settings on the servers and allow you to do many different things, the most popular being able to have your own custom 404 error pages. .htaccess isn't difficult to use and is really just made up of a few simple instructions in a text file.Will My Host Support It?This is probably the hardest question to give a simple answer to. Many hosts support .htaccess but don't actually publicise it and many other hosts have the capability but do not allow their users to have a .htaccess file. As a general rule, if your server runs Unix or Linux, or any version of the Apache web server it will support .htaccess, although your host may not...

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PHP and Cookies

This section of the tutorial covers the use of the PHP scripting language to set and read cookies. Cookies in PHP are not difficult to implement, and there are only two commands that need to be used with them. PHP makes it easy to set and read cookies and provides all the features needed to give their details.Setting a Basic CookieThe PHP function for setting cookies is called:setcookie()It is a PHP function which can be used without returning a value (for example you can simply execute a setcookie()) command, or you can take the return value and use it. The setcookie() function returns a boolean (true or false) value depending on whether it is successful. So you could execute:if(setcookie()){echo "Cookie set";}else{echo "Cookie not set";}For the purposes of this tutorial, though, we will...

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Cookies Tutorial

IntroductionCookies are a technology which can be easily and simply used by a Webmaster to achieve a great many very useful tasks when creating websites. Although cookies are well known to users, many people are not really sure what they are used for, and a large amount of webmasters don't realise the possibilities open to them when they use cookies. Others have been put off, thinking that they must be difficult to use, but in reality, cookies can be set and used by a simple command in most scripting languages. In this tutorial I'll cover setting and using cookies in PHP, JavaScript and ASP, as well as giving some basic information on how cookies can be used.What Is A Cookie?Apart from being a type of biscuit, a cookie is also a very useful piece of technology for use on the web. One of the...

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Caching Tutorial

What’s a Web Cache? Why do people use them?A Web cache sits between one or more Web servers (also known as origin servers) and a client or many clients, and watches requests come by, saving copies of the responses — like HTML pages, images and files (collectively known as representations) — for itself. Then, if there is another request for the same URL, it can use the response that it has, instead of asking the origin server for it again.There are two main reasons that Web caches are used:To reduce latency — Because the request is satisfied from the cache (which is closer to the client) instead of the origin server, it takes less time for it to get the representation and display it. This makes the Web seem more responsive.To reduce network traffic — Because representations are reused, it reduces...

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Bank ATM Security

ATM bank cash machines have been incorporated in our way of life. They offer a real convenience to those on the run, but at the same time offer an element of risk. Using a bank ATM machine safely requires awareness and a little planning. Just because a bank ATM machine is open and available 24-hours a day doesn't mean it is always safe to use it.ATM Robbery FactsMost bank ATM robberies occur at night between 7pm and midnight when the machine only produces 10% of the daily transactions. Between 7pm and 4am, the ATMs handle only 11% of the total daily transactions but suffer 60% of the crime.Who Are the Robbers?Bank ATM robbers are usually males under 25 years of age and most work alone. ATM robbers usually position themselves nearby (50 feet) waiting for a victim to approach and withdraw cash....

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How to Make a User Defined TagLike

most things in CMS, adding a new plug-in is simple, although it's not quite like a holiday.To add your own plugin follow these steps...1. The plugin editor is in the back-end so you need to login as admin, or a user with appropriate permissions.2. In the admin panel click on 'Plugin Management' on the menu bar on the left.3. At the bottom of the page click 'Add User Defined Tag'. 4. In the 'Name' text-box type the name of the tag. This is what you'll have to type in parenthesies to add a tag into a page so be descriptive but don't make it long. 5. In the 'Code' text-box type the php code that the tag will be replaced with when the page is requested. (Check the next section for more info) 6. Click on the 'Submit'. Your First UDTInstead of me rambling on about every last detail of plugins and...

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Introduction to XML Schema

XML Schema is an XML-based alternative to DTD.An XML schema describes the structure of an XML document.The XML Schema language is also referred to as XML Schema Definition (XSD).What You Should Already KnowBefore you continue you should have a basic understanding of the following:HTML / XHTMLXML and XML NamespacesA basic understanding of DTDIf you want to study these subjects first, find the tutorials on our Home page.What is an XML Schema?The purpose of an XML Schema is to define the legal building blocks of an XML document, just like a DTD.An XML Schema:defines elements that can appear in a documentdefines attributes that can appear in a documentdefines which elements are child elementsdefines the order of child elementsdefines the number of child elementsdefines whether an element is empty...

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The Port Forwarding Progression

If you are wondering where to start or what exactly needs to be done, you have come to the right place. This guide will provide a overview of what you need to do and know to forward ports to your computer. It will also provide an order to the guides on these pages, and help you avoid several pitfalls.In order to forward properly you really need to understand what port forwarding is. This might seem like an irrelevant step, but it is not. Port forwarding is akin to driving a car. It's very difficult for most people. The more you know about port forwarding easier it will be to get your ports from point A to point B. Imagine if tried to goto the store without first learning how to drive your car. Well enough of this introduction, let's get to work. The very first thing you should do is to read...

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