Book 7 does not load. It shows error I was downloading in Windows if that should be the problem. Thank you!! Thank you for great job! Exceptional collection! Mehedi hasan great work people should have a different approach towards linux and this article will change their prescriptive, meanwhile i would like to share one of the good material about linux i.
Linux From Scratch 8. Linux Shell Scripting Cookbook 9. Linux Hacks — Practical Examples to build a strong foundation on Linux The Linux Knowledge Base and Tutorial Advanced Bash-Scripting Guide Linux Dictionary Linux Filesystem Hierarchy Pro Ubuntu Server Administration Pocket Linux Guide Linux Fundamentals Little Orange Ubuntu Book — Ubuntu The Official Ubuntu Book Ubuntu Pocket Guide and Reference.
Featured Free e-Books Linux. Mehedi Hasan. Best Linux Tutorial Books This is why today I am going to share a list of best and useful free Linux Tutorial books to become a power and expert user. Table of Contents What is Linux? Bash Guide for Beginners This book shares in-depth knowledge about bash scripts, environment, GNU sed stream editor, awk programming language , variables, and so on.
User Mode Linux If you are learning about virtualization technologies, COW files, files system management, networking setup, host kernel, MConsole queries then this book is absolutely perfect for you. Linux Shell Scripting Cookbook This book is provided with more than tips and techniques to solve real-time shell scripting problems.
VTLS Chameleon iPortal Browse Results
Not At All! Shell Scripting: Expert Recipes for Linux, Bash, and More As like the above-mentioned books, this book also starts with the fundamental ingredients of Unix and Linux environment. The Linux Knowledge Base and Tutorial This book offers elementary and fundamental lessons of Linux system for the newbies.
Managing Linux Systems with Webmin: System Administration and Module Development This book is all about various system module management including file sharing, schedule commands, boot up and shutdown, system log management, php server configuration, database setup , proxy server setup, cluster software management, and much more for the newbies for becoming an expert.
Advanced Bash-Scripting Guide In no other Linux Tutorial books, you will be able to get with all in one solution for learning Advanced Bash script except this one. Table of Contents Shell Programming! Linux Dictionary Linux system includes some very confusing and difficult to remember commands and words which help the administrators to perform some specific task effectively and efficiently.
Linux Filesystem Hierarchy Linux files system is complex in nature and not easy to understand for the newbies. Pro Ubuntu Server Administration Ubuntu is the best and most popular Linux distro for desktop and server development. Pocket Linux Guide With the help of this Linux tutorial books, you will be able to learn Linux system starting from the basics and fundamental topic up to very complex theory with easy and step by step practical examples. Securing and Optimizing Linux: The Ultimate Solution Only learning the necessary things about Linux installation, upgrading, files management will not be proper and enough for those, who want to make their career on a Linux system.
The Linux Kernel Module Programming Guide In this book, you will not find any basic information of the Linux system rather this deals with a very fundamental core component of Unix or Linux base, that is Kernel module programming. Linux Fundamentals Just grabs this book. Table of Contents Ubuntu, your options, and is it right for you? Tags Linux Tutorial. Related Post. Script writing software is designed to play a vital role for writers from different writing sectors. As a newbie, it may not be simple Read more.
A-Z Commands. One of the main reasons behind the immense popularity enjoyed by Linux is its sheer prowess in networking. This escapes the foreign input ID before it is introduced to the database preventing potential SQL injection attacks. You should also be aware that database connections use up resources and it was not unheard-of to have resources exhausted if connections were not implicitly closed, however this was more common in other languages.
Using PDO you can implicitly close the connection by destroying the object by ensuring all remaining references to it are deleted, i. When developers first start to learn PHP, they often end up mixing their database interaction up with their presentation logic, using code that might look like this:.
While there are many other solutions to doing this - depending on if you prefer OOP or functional programming - there must be some element of separation. That is a good start. Create a simple. This is essentially the same as what most modern frameworks are doing, albeit a little more manual. You might not need to do all of that every time, but mixing together too much presentation logic and database interaction can be a real problem if you ever want to unit-test your application.
PHPBridge has a great resource called Creating a Data Class which covers a very similar topic, and is great for developers just getting used to the concept of interacting with databases. Many frameworks provide their own abstraction layer which may or may not sit on top of PDO. These will often emulate features for one database system that is missing from another by wrapping your queries in PHP methods, giving you actual database abstraction instead of just the connection abstraction that PDO provides.
This will of course add a little overhead, but if you are building a portable application that needs to work with MySQL, PostgreSQL and SQLite then a little overhead will be worth it the sake of code cleanliness.
An overview of major Linux distributions and FreeBSD
Some abstraction layers have been built using the PSR-0 or PSR-4 namespace standards so can be installed in any application you like:. Templates provide a convenient way of separating your controller and domain logic from your presentation logic. The main benefit to using templates is the clear separation they create between the presentation logic and the rest of your application. Templates have the sole responsibility of displaying formatted content.
They are not responsible for data lookup, persistence or other more complex tasks. This leads to cleaner, more readable code which is especially helpful in a team environment where developers work on the server-side code controllers, models and designers work on the client-side code markup. Templates also improve the organization of presentation code. This approach encourages code reuse where larger blocks of code are broken into smaller, reusable pieces, often called partials. For example, your site header and footer can each be defined as templates, which are then included before and after each page template.
Finally, depending on the library you use, templates can offer more security by automatically escaping user-generated content. Some libraries even offer sand-boxing, where template designers are only given access to white-listed variables and functions. They are a natural choice since PHP is actually a template language itself.
This is beneficial to PHP developers as there is no new syntax to learn, they know the functions available to them, and their code editors already have PHP syntax highlighting and auto-completion built-in. Further, plain PHP templates tend to be very fast as no compiling stage is required. Outside of frameworks, libraries like Plates or Aura. View make working with plain PHP templates easier by offering modern template functionality such as inheritance, layouts and extensions.
From automatic escaping, to inheritance and simplified control structures, compiled templates are designed to be easier to write, cleaner to read and safer to use. Compiled templates can even be shared across different languages, Mustache being a good example of this. Since these templates must be compiled there is a slight performance hit, however this is very minimal when proper caching is used.
While it does have exceptions and more of the core is starting to use them when working with objects, most of PHP itself will try to keep processing regardless of what happens, unless a fatal error occurs. This is only a notice error, and PHP will happily carry on. The only real difference is that Python will freak out over any small thing, so that developers can be super sure any potential issue or edge-case is caught, whereas PHP will keep on processing unless something extreme happens, at which point it will throw an error and report it.
PHP has several levels of error severity.
The three most common types of messages are errors, notices and warnings. Notices are advisory messages caused by code that may or may not cause problems during the execution of the script, execution is not halted. Warnings are non-fatal errors, execution of the script will not be halted. These messages are used to suggest changes to your code to help ensure best interoperability and forward compatibility with upcoming versions of PHP. You can also control whether or not errors are displayed to the screen good for development or hidden, and logged good for production.
For more information on this check out the Error Reporting section. This might seem like a good idea, but there are a few undesirable tradeoffs. PHP handles expressions using an in a less performant way than expressions without an. Secondly, the error control operator completely swallows the error. The error is not displayed, and the error is not sent to the error log. For example, our code above could be rewritten like this:.
One instance where error suppression might make sense is where fopen fails to find a file to load. You could check for the existence of the file before you try to load it, but if the file is deleted after the check and before the fopen which might sound impossible, but it can happen then fopen will return false and throw an error. This is potentially something PHP should resolve, but is one case where error suppression might seem like the only valid solution.
However, Xdebug has an xdebug. You can set this via your php. Use scream with care, and as a temporary debugging tool. This is a common practice implemented by a large number of modern frameworks such as Symfony and Laravel. In debug mode or dev mode both of these frameworks will display a nice and clean stack trace.
There are also some packages available for better error and exception handling and reporting. Like Whoops! By throwing errors as exceptions in development you can handle them better than the usual result, and if you see an exception during development you can wrap it in a catch statement with specific instructions on how to handle the situation. Each exception you catch instantly makes your application that little bit more robust. More information on this and details on how to use ErrorException with error handling can be found at ErrorException Class.
Exceptions are a standard part of most popular programming languages, but they are often overlooked by PHP programmers. Languages like Ruby are extremely Exception heavy, so whenever something goes wrong such as a HTTP request failing, or a DB query goes wrong, or even if an image asset could not be found, Ruby or the gems being used will throw an exception to the screen meaning you instantly know there is a mistake. The problem here is that you have to go looking for a mistake and check the docs to see what the error method is for this class, instead of having it made extremely obvious.
Another problem is when classes automatically throw an error to the screen and exit the process. When you do this you stop another developer from being able to dynamically handle that error. Exceptions should be thrown to make a developer aware of an error; they then can choose how to handle this.
The generic Exception class provides very little debugging context for the developer; however, to remedy this, it is possible to create a specialized Exception type by sub-classing the generic Exception class:. This means you can add multiple catch blocks and handle different Exceptions differently. This can lead to the creation of a lot of custom Exceptions, some of which could have been avoided using the SPL Exceptions provided in the SPL extension. It is very important for every PHP developer to learn the basics of web application security , which can be broken down into a handful of broad topics:.
There are bad people ready and willing to exploit your web application. This is a must read for the security-conscious developer. Eventually everyone builds a PHP application that relies on user login. Usernames and passwords are stored in a database and later used to authenticate users upon login. It is important that you properly hash passwords before storing them. Hashing and encrypting are two very different things that often get confused.
Hashing is an irreversible, one-way function. This produces a fixed-length string that cannot be feasibly reversed. This means you can compare a hash against another to determine if they both came from the same source string, but you cannot determine the original string. If passwords are not hashed and your database is accessed by an unauthorized third-party, all user accounts are now compromised.
Unlike hashing, encryption is reversible provided you have the key. Encryption is useful in other areas, but is a poor strategy for securely storing passwords. Passwords should also be individually salted by adding a random string to each password before hashing. Hashing and salting are vital as often users use the same password for multiple services and password quality can be poor. Additionally, you should use a specialized password hashing algorithm rather than fast, general-purpose cryptographic hash function e. The short list of acceptable password hashing algorithms as of June to use are:.
In PHP 5. It will be updated in the future to support more algorithms as needed though. Below we hash a string, and then check the hash against a new string. Never ever ever trust foreign input introduced to your PHP code. Always sanitize and validate foreign input before using it in code.
Remember, foreign input is not limited to form data submitted by the user. Uploaded and downloaded files, session values, cookie data, and data from third-party web services are foreign input, too. While foreign data can be stored, combined, and accessed later, it is still foreign input.
Every time you process, output, concatenate, or include data in your code, ask yourself if the data is filtered properly and can it be trusted. Data may be filtered differently based on its purpose. Another example is passing options to be executed on the command line. One last example is accepting foreign input to determine a file to load from the filesystem. This can be exploited by changing the filename to a file path. When you use bound parameters with PDO , it will sanitize the input for you. This is very hard to do and many avoid it by using other more restricted formatting like Markdown or BBCode, although whitelisting libraries like HTML Purifier exists for this reason.
It is dangerous to unserialize data from users or other untrusted sources. You should therefore avoid unserializing untrusted data. Validation ensures that foreign input is what you expect. For example, you may want to validate an email address, a phone number, or age when processing a registration submission. When creating configuration files for your applications, best practices recommend that one of the following methods be followed:. This is only included as a warning for anyone in the process of upgrading a legacy application.
This can easily lead to security issues as your application cannot effectively tell where the data is coming from. Error logging can be useful in finding the problem spots in your application, but it can also expose information about the structure of your application to the outside world. To effectively protect your application from issues that could be caused by the output of these messages, you need to configure your server differently in development versus production live.
To show every possible error during development , configure the following settings in your php. Passing in the value -1 will show every possible error, even when new levels and constants are added in future PHP versions. What does this mean? In terms of reporting every possible error in version 5. To hide errors on your production environment, configure your php. With these settings in production, errors will still be logged to the error logs for the web server, but will not be shown to the user. For more information on these settings, see the PHP manual:.
Writing automated tests for your PHP code is considered a best practice and can lead to well-built applications.
- 21.2. IBM Redbooks Publications for IBM Z.
- Linux bible.
- 67 open source tools and resources for the Internet of Things (IoT).
Automated tests are a great tool for making sure your application does not break when you are making changes or adding new functionality and should not be ignored. Test-driven development TDD is a software development process that relies on the repetition of a very short development cycle: first the developer writes a failing automated test case that defines a desired improvement or new function, then produces code to pass that test and finally refactors the new code to acceptable standards.
Unit Testing is a programming approach to ensure functions, classes and methods are working as expected, from the point you build them all the way through the development cycle. By checking values going in and out of various functions and methods, you can make sure the internal logic is working correctly. When you create a class or function you should create a unit test for each behavior it must have. At a very basic level you should make sure it errors if you send it bad arguments and make sure it works if you send it valid arguments.
This will help ensure that when you make changes to this class or function later on in the development cycle that the old functionality continues to work as expected. The other use for unit tests is contributing to open source. If you can write a test that shows broken functionality i. If you run a project which accepts pull requests then you should suggest this as a requirement. PHPUnit is the de-facto testing framework for writing unit tests for PHP applications, but there are several alternatives. It occurs after unit testing and before validation testing. Integration testing takes as its input modules that have been unit tested, groups them in larger aggregates, applies tests defined in an integration test plan to those aggregates, and delivers as its output the integrated system ready for system testing.
Many of the same tools that can be used for unit testing can be used for integration testing as many of the same principles are used. Sometimes also known as acceptance testing, functional testing consists of using tools to create automated tests that actually use your application instead of just verifying that individual units of code are behaving correctly and that individual units can speak to each other correctly.
These tools typically work using real data and simulating actual users of the application. With StoryBDD, you write human-readable stories that describe the behavior of your application. These stories can then be run as actual tests against your application. With SpecBDD, you write specifications that describe how your actual code should behave. Instead of testing a function or method, you are describing how that function or method should behave. This framework is inspired by the RSpec project for Ruby.
Besides individual testing and behavior driven frameworks, there are also a number of generic frameworks and helper libraries useful for any preferred approach taken. PaaS provides the system and network architecture necessary to run PHP applications on the web. Recently PaaS has become a popular method for deploying, hosting, and scaling PHP applications of all sizes. It uses less memory than Apache and can better handle more concurrent requests.
PHP and Apache have a long history together. Apache is wildly configurable and has many available modules to extend functionality. It is a popular choice for shared servers and an easy setup for PHP frameworks and open source apps like WordPress. Unfortunately, Apache uses more resources than nginx by default and cannot handle as many visitors at the same time.
Apache has several possible configurations for running PHP. This configuration will be significantly more memory efficient and much faster but it is more work to set up. If you are running Apache 2. PHP has shared servers to thank for its popularity. Shared servers allow you and other developers to deploy websites to a single machine. The upside to this is that it has become a cheap commodity. The downside is that you never know what kind of a ruckus your neighboring tenants are going to create; loading down the server or opening up security holes are the main concerns.
If you find yourself doing manual database schema changes or running your tests manually before updating your files manually , think twice! With every additional manual task needed to deploy a new version of your app, the chances for potentially fatal mistakes increase. Deployment tools can be described as a collection of scripts that handle common tasks of software deployment. Here are a few examples:. Phing can control your packaging, deployment or testing process from within a XML build file. Phing which is based on Apache Ant provides a rich set of tasks usually needed to install or update a web application and can be extended with additional custom tasks, written in PHP.
Capistrano is a system for intermediate-to-advanced programmers to execute commands in a structured, repeatable way on one or more remote machines. It is pre-configured for deploying Ruby on Rails applications, however you can successfully deploy PHP systems with it. Successful use of Capistrano depends on a working knowledge of Ruby and Rake. Ansistrano is a couple of Ansible roles to easily manage the deployment process deploy and rollback for scripting applications such as PHP, Python and Ruby.
Rocketeer gets its inspiration and philosophy from the Laravel framework. Its goal is to be fast, elegant and easy to use with smart defaults. It features multiple servers, multiple stages, atomic deploys and deployment can be performed in parallel. Everything in the tool can be hot swapped or extended, and everything is written in PHP. Deployer is a deployment tool written in PHP.
Features include running tasks in parallel, atomic deployment and keeping consistency between servers. It has support for multiple servers and environments, atomic deployment, and has some built in tasks that you can leverage for common tools and frameworks. Managing and configuring servers can be a daunting task when faced with many servers.
They often integrate with the larger cloud hosting providers Amazon Web Services, Heroku, DigitalOcean, etc for managing instances, which makes scaling an application a lot easier. Ansible is a tool that manages your infrastructure through YAML files. Canonical Ubuntu and Snappy Ubuntu Core. Qeo Tinq. Chimera IoT. Pico Labs Kynetx open source assigned to Pico Labs.
M2MLabs Mainspring. Arduino Ethernet Shield. Intel Galileo. Eclipse SmartHome. The Thing System. Open Source Robotics Foundation.
- Browse Search.
- Trump Strategies for Real Estate: Billionaire Lessons for the Small Investor.
- Share this article.
- Catching Midnight (Upyr).
- Mental Floss Presents Be Amazing: Glow in the Dark, Control the Weather, Perform Your Own Surgery, Get Out of Jury Duty, Identify a Witch, Colonize a Nation, ... Girl, Make a Zombie, Start Your Own Religion!
HabitatMap Airbeam. Oxford Flood Network. For most businesses, the top priority in building an IoT solution is interoperability. These standards and protocols enable systems and devices to find each another and communicate across profiles, such as mobile, wearables, in-vehicle infotainment, TV, cameras, printers, and appliances. The standard plus the implementation reference helps to ensure interoperability among products, regardless of the manufacturer or vertical.
The AllSeen Alliance describes themselves as "dedicated to enabling and driving the widespread adoption of products, systems, and services that support the Internet of Everything with an open, universal development framework supported by a vibrant ecosystem and thriving technical community. It is the broadest cross-industry consortium to date that advances adoption and innovation in the Internet of Everything in homes and industry and looks to expand to healthcare, education, automotive, and enterprise. Its salient capability is in the abstraction transport layer.
Because a critical market requirement is the ability to scale, firms are looking for platforms that can support large-scale deployments. So, what are some available options for businesses to consider?
Described by mqtt. Constrained Application Protocol CoAP is an application layer protocol intended for use in resource-constrained Internet devices, such as wireless sensor network nodes, low power sensors, switches, valves, and components controlled or monitored remotely through Internet networks. The key here is resource constrained. XMPP has been extended to use in publish-subscribe systems and IoT applications, such as for the smart grid. An open-standard application layer protocol designed for message-oriented middleware, Advanced Message Queuing Protocol AMQP features message orientation, queuing, routing including point-to-point and publish-and-subscribe , reliability, and security.
SiteWhere enables businesses to create IoT solutions without custom coding. Devices can be assigned to physical or logical assets via pluggable, commercial, off-the-shelf modules.
Event data can be stored in the cloud or on local servers. The solution is fault tolerant, scalable, and cost efficient. Communication with devices is bidirectional and asynchronous. This allows SiteWhere to manage solutions that require very large numbers of devices and event cycles. SiteWhere provides interfaces for customized event triggering, searching, and analytics, as well as out-of-the-box support for rapidly integrating customized device data into other platforms.
SiteWhere claims that their solution is faster to deploy than Xively, with the advantage of deploying in the cloud and the local server. Each gateway consists of a complete end-to-end specification of reference hardware, core platform, and example applications. When we talk about scale and fragmented device environment, nothing poses a greater challenge than smart cities.
For those firms looking for a smart city open source toolset, consider these projects for the OS layer. Both RIOT and Contiki focus on sensors with very minimal processing and memory, allowing the full OS capability on tiny sensor devices that otherwise wouldn't be able to support Linux or Android because of the lack of power, memory, and processing. It has highly efficient memory allocation, full IP networking, low power consumption, and dynamic module loading.
OpenRemote is a middleware solution with a focus on home automation, commercial buildings, public spaces, and healthcare. OpenRemote is protocol-agnostic and operates on off-the-shelf hardware. OpenRemote's architecture enables fully autonomous and user-independent intelligent buildings. End user control interfaces are available for iOS, Android, and web-browser-based devices.
User interface design, installation management, and configuration can be handled remotely with OpenRemote's cloud-based design tools. A public space case study is based on the City of Eindhoven's use of OpenRemote. They were able to build a crowd management system with workflow and messaging. Data visualization software was integrated with devices, sensors, and subsystems via a local controller or hub. Using street sensors, the system was able to count the number of people passing, measure city sound levels, and use lighting as an actuator. A UI dashboard was available on mobile devices to view crowd management metrics.
For those companies interested in entering the smart home category, what are some open source projects that can give you a head start? Here are two smart home platforms to consider:. Eclipse SmartHome tries to address the fragmented smart home ecosystem with common interfaces and APIs to integrate connectivity, automation, user interfaces, and persistence.
HGI is a consortium of major broadband service providers Deutsche Telekom, Telecom Italia, NTT and home consumer electronics manufacturers to build a smart home ecosystem. HGI publishes requirements and test plans for home gateways and wireless home networks with the goal of enabling applications, home gateway middleware, and home-network-based devices to connect seamlessly.
Piecing together various components and services is no simple matter.
Yet, your stakeholders demand quick benefits. So, how can organizations achieve this? Zetta powers commercial platforms like Apigee. On the middleware side, OpenIoT creates an open source middleware for pulling information from sensor clouds, without having to worry about what sensors are used. It explores efficient ways to use and manage cloud environments for IoT entities and resources, such as sensors, actuators, and smart devices, and offers a cloud- and utility-based sensing-as-a-service model via an adaptive middleware framework for deploying and providing services in cloud environments.
OpenIoT has developed use cases for smart agriculture, intelligent manufacturing, urban crowdsensing, smart living, and smart campuses. Depending on the solution you're building, there may be use cases where Wi-Fi and cellular coverage will be limited. What do you do then? Whether we're talking about live events, remote areas, or agricultural land, a mesh network offers connectivity when there's limited Wi-Fi or cellular service.
Open Garden SDK enables connected devices to connect to the Internet and communicate with other nearby devices using peer-to-peer mesh networking connectivity to share and receive data faster and more efficiently by automatically and actively choosing and switching to the best available network without requiring a user's involvement. Founders claims that more than five million people are using Open Garden.
Some startups are using Open Garden and a low-power wide-area network LPWAN to create an off-the-grid, wireless messaging network that claims to work over a mile radius and support up to 50 kilobits per second over 50 channels. The routing layer is responsible for relaying packets across multiple hops separating source and destination nodes. It's divided into a forwarding engine, which uses a routing table to decide which neighbor node is the next hop for that packet, as well as a routing protocol, which populates the routing table.
Another market requirement we hear about often is the ability to monetize based on utility.