Blog features Web development tips and tutorials. What is the Relationship of Linux to UNIX. The Origins and Development of UNIX Across the Decades and Its Relationship to Linux. A Brief History of UNIX UNIX development truly began in the 1960's under the name Multics, a project that yielded little monetary results and was abandoned by one of the major companies that contributed to its development.
However, work on the project was continued by some of the individuals involved and eventually culminated in the birth of Unics (a play on "Multics", later renamed to UNIX) in the 1970's. In the 1980s, AT&T implemented commercial licenses on UNIX distributions and streamlined all versions into one: UNIX System V. The University of California, Berkeley, continued development of its own version of UNIX, called BSD. Through the 80's and 90's, many companies commercialized and licensed their own versions of UNIX, including Sun Microsystems, Microsoft, and SCO, among others.
All of this buying, selling, licensing, de-licensing, and independent development of the 90's eventually led to law suits, disputes, and drama over who owned what parts of what UNIX. Why is Git so Fast? In the DVCS world, Git has a reputation for being really fast. I am curious about how Git got this way. When I started thinking about this question, seven different answers came to my mind. Some of those answers seem more interesting or correct than others. One: Maybe Git is fast simply because it's a DVCS. There's probably some truth here.
But this answer isn't enough. Two: Maybe Git is fast because Linus Torvalds is so smart. This might very well be correct. Fine. Three: Maybe Git is fast because it's written in C instead of one of those newfangled higher-level languages. Nah, probably not. And lots of people have written really slow software in traditional native languages like C/C++.
Four: Maybe Git is fast because being fast is the primary goal for Git. This is another one of those high-level answers that is probably correct but doesn't have the kind of details about which I am curious. Still. Five: Maybe Git is fast because it does less. But this guy was essentially correct. What is Node.js? What is 3 tier Architecture: and Why do You need it. What is 3 Tier Architecture and Why Do You Need It? Three-tier or multi-tier architecture is often used when describing how clients connect to database servers. But what does it all mean? Let me try to explain this in non-technical terms (or as close to it I can get). Software Let’s first take a look how a database software program (the software) works. There are three major tiers to the software: -User Interface (UI). 1-Tier Architecture This architecture has the UI, the BL, and the DB in one single software package.
Another issue is that 1-tier software packages are not very scalable and if the amount to data gets too big, the software may be very slow or stop working. So 1-tier architecture is simple and cheap, but usually unsecured and data can easily be lost if you are not careful. 2-Tier Architecture This architecture is also called Client-Server architecture because of the two components: The client that runs the application and the server that handles the database back-end. 7 reasons to switch from Drupal to Yii. Drupal 7 is about to be released, so many organizations need to decide whether to upgrade from Drupal 5 or 6. Drupal is fine if you're building lots of websites and need to create new sites quickly without much coding, or if you just need a blog-on-steroids content site. Running on Drupal is like living in a double-wide: it's the best solution if you can't afford a custom home.
If you have a site that started on Drupal and has grown enough to employ full-time developers, you should consider migrating your site to the Yii PHP framework. (PHP haters can follow The Onion and use the Django Python framework, although it will take more time to change frameworks and programming languages.) I'm the CTO of a site that switched from Drupal to Yii on April 30th 2010. It was hard to find information when we were debating a rewrite and there wasn't even a book about Yii yet. Yii was much faster than Drupal for our site with 150,000 nodes (each with a rewritten URL) and 50,000 visitors per day. Hello World · GitHub Guides. The Hello World project is a time-honored tradition in computer programming. It is a simple exercise that gets you started when learning something new. Let’s get started with GitHub! You’ll learn how to: Create and use a repository Start and manage a new branch Make changes to a file and push them to GitHub as commits Open and merge a pull request What is GitHub?
GitHub is a code hosting platform for version control and collaboration. This tutorial teaches you GitHub essentials like repositories, branches, commits, and Pull Requests. No coding necessary To complete this tutorial, you need a GitHub.com account and Internet access. Tip: Open this guide in a separate browser window (or tab) so you can see it while you complete the steps in the tutorial. Step 1. A repository is usually used to organize a single project. Your hello-world repository can be a place where you store ideas, resources, or even share and discuss things with others.
To create a new repository Click Create repository. Don’t Test Blindly: The Right Methods for Unit Testing Your Java Apps. Quick-tro In my previous blog post Why Your Next Cloud App Will Probably Suck Without…Unit Testing, we gave an overview promoting the benefits of unit tests, and how these small, simple actions can make a big difference in getting bug-free, solidly-built applications out the door. After reading this, I can assume that you have jumped out of your chair and started frantically writing them for your big enterprise project, right?
Well, stop now! Before writing a single unit test, it’s necessary to determine exactly what to test. A big enterprise application can hold a billion lines of code, so do you think it’s realistic to write tests for everything? Not exactly. What you should NOT test You can spend your entire life testing away if you like, but it’s probably best to to make some assumptions in the beginning to save yourself some time. I’ll ask you to trust my 8 years in software development when I say you should NOT write units tests for: What you SHOULD test Learn which tools rock! Teach Yourself Programming in Ten Years. Job title - When should you call yourself a senior developer? How to enable keep-alive for faster page speed. If the browser and server had to have this communication for each file transferred then the entire affair would take longer than if the server could just say "grab whatever files you need".
When a web browser wants to display a webpage it must first get the HTML file. It will then read the HTML file and request more files that the HTML references like CSS or images or whatever file the HTML is requesting. When keep alive is not enabled this can add alot of time to the downloading of a webpage. Webpages are often a collection of many files and if a new connection (the brief communication) has to be opened for each and everyone of those files it could take significantly longer to display that webpage. More officially the definition of HTTP keep-alive would be something like "a method to allow the same tcp connection for HTTP conversation instead of opening new one with each new request". How to enable keep-alive Since keep-alive is default, there is some reason your pages aren't using it.
Caching Tutorial for Web Authors and Webmasters. For Web Authors and Webmasters This is an informational document. Although technical in nature, it attempts to make the concepts involved understandable and applicable in real-world situations. Because of this, some aspects of the material are simplified or omitted, for the sake of clarity. If you are interested in the minutia of the subject, please explore the References and Further Information at the end. What’s a Web Cache? 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. 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. Kinds of Web Caches Browser Caches Proxy Caches Gateway Caches.
How big are PHP arrays (and values) really? (Hint: BIG!) Upfront I want to thank Johannes and Tyrael for their help in finding some of the more hidden memory usage. In this post I want to investigate the memory usage of PHP arrays (and values in general) using the following script as an example, which creates 100000 unique integer array elements and measures the resulting memory usage: $startMemory = memory_get_usage();$array = range(1, 100000);echo memory_get_usage() - $startMemory, ' bytes'; How much would you expect it to be? Simple, one integer is 8 bytes (on a 64 bit unix machine and using the long type) and you got 100000 integers, so you obviously will need 800000 bytes. That’s something like 0.76 MBs. Now try and run the above code. So, where does that extra factor of 18 come from?
Summary For those who don’t want to know the full story, here is a quick summary of the memory usage of the different components involved: | 64 bit | 32 bit The above numbers will vary depending on your operating system, your compiler and your compile options. Advantages of loading jQuery using CDN | Chetan Singh's b:log. Site Speed - Are You Fast? Does it Matter for SEO? Getting Started. Most webmasters are familiar with HTML tags on their pages. Usually, HTML tags tell the browser how to display the information included in the tag. For example, <h1>Avatar</h1> tells the browser to display the text string "Avatar" in a heading 1 format. However, the HTML tag doesn't give any information about what that text string means—"Avatar" could refer to the hugely successful 3D movie, or it could refer to a type of profile picture—and this can make it more difficult for search engines to intelligently display relevant content to a user.
Schema.org provides a collection of shared vocabularies webmasters can use to mark up their pages in ways that can be understood by the major search engines: Google, Microsoft, Yandex and Yahoo! 1. How to mark up your content using microdata 1a. Your web pages have an underlying meaning that people understand when they read the web pages. 1b. itemscope and itemtype Let's start with a concrete example. Back to top 1c. itemprop 1d. 2. 2b. 2c. 3. 3a. 3b.
Web Forms. You are here: Home Dive Into HTML5 Diving In Everybody knows about web forms, right? Make a <form>, a few <input type="text"> elements, maybe an <input type="password">, finish it off with an <input type="submit"> button, and you’re done. You don’t know the half of it. HTML5 defines over a dozen new input types that you can use in your forms. Placeholder Text The first improvement HTML5 brings to web forms is the ability to set placeholder text in an input field. You’ve probably seen placeholder text before. When you click on (or tab to) the location bar, the placeholder text disappears: Here’s how you can include placeholder text in your own web forms: Browsers that don’t support the placeholder attribute will simply ignore it. Ask Professor Markup Q: Can I use HTML markup in the placeholder attribute? Autofocus Fields Web sites can use JavaScript to focus the first input field of a web form automatically.
Here’s how you can set a form field to autofocus: What’s that? Autofocus with fallback. HTML5 for the Mobile Web - Forms and Input Types. In this article we take a look at some of the new form enhancements available in HTML5, and look at how they contribute to an improved user experience for mobile forms. In particular we will see how forms can be enhanced with the additional input types offered by HTML5, and show what you can expect across various classes of mobile browser. HTML5 Input Types HTML5 has a bunch of new input types for forms. These input types allow better input control and validation, some of which are particularly useful for mobile users, where input is often more cumbersome than on desktop. The full list of input types is included below: In the following sections, we take a look at some of the more interesting ones, such as color, date, email, range, tel, which have fairly obvious application to mobile devices. Input type color When supported, using this input type will trigger a colour-picker on the client device.
Usage: Color input as implemented on Opera Mobile, and Chrome browsers on Android Try it: Try it: HTML5 forms input types. In the first article in this series we looked at the history of HTML5 forms and many of the new attributes available to us. In this second and final part of the series, we’ll look at the new input types available in HTML5. As we’ll see, these new features will go a long way toward making your life easier while delivering a delightful user experience. The best thing about all this? You can start using them now. HTML5 introduces no less than a baker’s dozen (yes, that’s 13!) Search Search seems like an appropriate place to start our foray into HTML5 input types.
Well, what if we could write something like … With HTML5 we can. On a mobile device, however, things start to get interesting. As you’ve seen with the new attributes, browsers that don’t understand them will simply degrade gracefully. Email In rendering terms, the email input type is no different than a standard text input type and allows for one or more e-mail addresses to be entered. Pretty cool, huh? Did you notice it this time? 12 PHP Debugging Tools for Developers. PHP is faster and most used scripting language in practice; contains many features such as detailed documentation, a huge community, myriad of ready-to-use scripts and well-supported frameworks.
Its quite easy to get started with PHP than with other scripting languages such as Python, or Ruby because of the features PHP provides. PHP Developers keep looking for useful PHP tools for creating innovative and interesting web applications. In this article I have gathered 12 PHP Debugging Tools for Developers which will help developers to easily find out and debug the errors in their applications and scripts. Following PHP debugging tool supports Ajax requests and includes generic data collectors and stack based error handling. If you like the article you might be interested in our other articles on 8 New PHP Tools for Developers and 10 Useful PHP Scripts. 1.
When debugging PHP code, var_dump(), print_r() and debug_backtrace()are usually our best friends. 2. 3. 5. 6. 7. 8. 9. 10. 11. 12. CSS Sprites: Image Slicing’s Kiss of Death. Back when video games were still fun (we’re talking about the 8-bit glory days here), graphics were a much simpler matter by necessity. Bitmapped 2-dimensional character data and background scenery was individually drawn, much like today’s resurgent pixel art.
Hundreds and later thousands of small graphics called sprites were the building blocks for all things visual in a game. Article Continues Below As game complexity increased, techniques developed to manage the multitude of sprites while keeping game play flowing. One variation saw sprites being plugged into a master grid, then later pulled out as needed by code that mapped positions of each individual graphic, and selectively painted them on the screen. And what does this have to do with the web? Everything old is new again, and though the rise of 3D games has made sprite maps obsolete, the concurrent rise of mobile devices with 2D gaming capabilities have brought them back into vogue. How do CSS Sprites work? On to the HTML. Single sign-on. OWASP Top 10 - 2010. CSRF Protection in CodeIgniter 2.0: A closer look - Bastian Heist - Webdesign Development Hosting.
Creating a new test case. Captain Debug's Blog: The Three Laws of Test Driven Development. Developing a Digital Video Library with the YouTube Data API. Death to Paging! - Rico LiveGrid Released.