The scalability and flexibility of Linux enable many of these massive deployments to actually work, while the significantly reduced cost barriers of Linux make them more financially feasible. In times of spiraling student debt, that's an understandable reaction. The overhead of symbolic links is minimal, but it is still considered …

The analogy is also frequently made with recipes for cooking food. These applications are not going away anytime soon. It doesn't take long to realize that this isn't how open source software works. Kernel modules, like the kernel itself, are usually written in C.

No more mistakes with watch

Secondly, the DMA controller cannot access the whole of physical memory. You can also edit boot options on the fly from the GRUB menu. An INET socket would have an IP port address bound to it. It sounds counterintuitive and/or just plain stupid on paper, but is generally seen …

It sounds counterintuitive and/or just plain stupid on paper, but is generally seen as the traditional and conservative way to do it. Each approach has its advantages and disadvantages. The source code for proprietary software is usually not made publicly available, or, if it is, there are generally severe …

Every process except the first has a parent. Every transmitted ethernet frame can be seen by all connected hosts and so every ethernet device has a unique address. There is also the reverse function, Reverse ARP or RARP, which translates phsyical network addresses into IP addresses. This pragmatic approach forces …

Very little Free Software would be written, and that which was written may not be released to the public. (See "Shell Built-in Commands.") Readline has variables that can be used to further customize its behavior. Sections are linear chunks of the object code that load into linear chunks of memory …

Interfaces documented by standards, such as the standard C library, will obviously always remain source compatible. It is the responsibility of the developers to fix these bugs as reported. The smallest addressable unit on a block device is the sector. Developing the core is pretty serious business, involving pretty serious …

Members of this process group (processes whose process group ID is equal to the current terminal process group ID) receive keyboard-generated signals such as SIGINT. Often the quickest way to access KPPP to set up an Internet connection is to open a terminal window (i.e., a text-only window in …

The basics of Unix programming have existed untouched for decades. Reading and changing a data source: An exampleA Linux machine is going to generate a lot of data in its day-to-day activity. Major players in the commercial arena are taking serious notice of Linux. Thereafter all of the applications file …

If job control is in effect, bash ignores SIGTTIN, SIGTTOU, and SIGTSTP. If you are just getting started with operating system development, this is not really the place to start. If this company transitions to another operating system, its staff would need to be retrained or hired, and much of …

However, diving in without an understanding of those projects, their communities, and how they operate can lead to frustrations for those companies as well as the open source communities. Connecting to the Internet with Linux is fairly simple. Secondly, the DMA controller cannot access the whole of physical memory. None …

The reality is that not only are more and more businesses and other organizations finding out that Linux can help reduce the costs of using computers, but also that more and more companies are likewise discovering that Linux can also be a great way to make money. Critical mass will …

Each command comes with a manual page which can be used to learn about its function as well as what options and arguments each specific command accepts. Before I became involved in Free Software, I had far different opinions, ideas, and beliefs than I do today. A security breach unnoticed …

This translates into a lot of time for UNIX to get it right - something Microsoft is still struggling with. So, /dev/hda2, the second partition of the primary IDE disk has a major number of 3 and a minor number of 2. If you tried to code up something similar …

It is possible to install Linux on the same computer (and on the same HDD or on a second one) as Microsoft Windows or any other operating system(s). Even if you are an aged UNIX guru, what follows is probably of interest to you. Linux is not like this …

From the process's perspective, the view of the system is as though it alone were in control. Most systems built now use PCI and ISA buses to connect together the main system components. That's particularly important in a period of significant technological change. Thanks to Linux and the broader world …

It's highly recommended for advanced programmers and system administrators. Special files are kernel objects that are represented as files. Although, there's no rocket science in it. Or, you can make a profit on support and ancillary sales on things like manuals, mouse pads or whatever suits your fancy.

Redirecting output …

The stuff which really needs to be automated is automated and the stuff which can teach you something is left manual. Not often are our basic rights thought of in the context of technology, but as more and more our lives are dependent on technology, it is a rapidly growing …

Moreover, most programming languages (if they aren't limited to a particular OS) work on Linux. Because your server will be probably Linux-based as well, it will be easier for you to mimic behaviors, use similar software and packages and automate work flows for your deployment processes. You can easily see …

Its entries are also device_struct data structures. Over the years, Unix systems have supported a handful of different special files. This must happen as the module cannot expect to be loaded at the same address twice let alone into the same address in two different Linux systems. Most open source …

When you boot a system that uses the GRUB Legacy bootloader, you'll see a menu that shows the boot options that you defined in the configuration file. In a very real sense Linux is a product of the Internet or World Wide Web (WWW). Device drivers have to be careful …

Its purpose is to provide a financial incentive for producing such works in order to benefit society as a whole. How does the kernel know which directory to look in to find a given filename? Any microprocessor that wishes to support an operating system must have a programmable interval timer …

Once the parent process has waited on its terminated child, the child is fully destroyed. That is, there are no legal restrictions on anyone using, studying, copying, modifying, improving or publishing any recipe. Each time a device driver runs, maybe as an interrupt is received or as a bottom half …

There is yet one other weakness: if a computer switches operating systems later, the long uptime is credited to the new OS. Imagine if you wanted to become a great writer but weren't allowed to read any books. In general, there is a tendency for advocates of the term term …

The mini-bootloader acts as a middleman in the boot process. If you hit Tab again it will show you those possibilities. Even if you are an aged UNIX guru, what follows is probably of interest to you. If a match is found, that builtin is invoked.

A lazy person's guide …

Everything a good programmer can wish for is available: compilers, libraries, development and debugging tools. I use Linux for everything. Almost certainly, but it's doubtful that it would maintain the presence that Android currently enjoys in today's consumer market. Usually, as bytes in the file are read from or written …

Its latest releases often inspire the other Linux distributions to adopt new features and make changes. Any site that is requested through the "what's that site running" query form at Netcraft.com is added to the set of sites that are routinely sampled; Netcraft doesn't routinely monitor all 22 million …

and insert it as the first line of your script. Some people, particularly members of the Free Software Foundation, refer to this collection as GNU/Linux, because many of the tools included are GNU components. These categories determine what powers are available to a user. Unlike Windows, Linux requires each …

An inode stores metadata associated with a file, such as its modification timestamp, owner, type, length, and the location of the file's data-but no filename! Sed, as you saw in our example, is basically used for altering a text file without actually having to open it up in a traditional …

You might be amazed that such a nonstructured system of volunteers, programming and debugging a complete UNIX system, could get anything done at all. The first way is to use the insmod command to manually insert the it into the kernel. There is also a devout following of Linux. It's …

In this article we will introduce you to why these accounts are important. Whenever a process has to wait the operating system takes the CPU away from that process and gives it to another, more deserving process. If you love the rolling Linux distributions (here are some fixed vs rolling …

However, Linux does not require the use of such Anti-Virus programs. The kernel modules are linked object files just like other programs in the system except that they are linked as a relocatable images. For many people, the next step will be to carefully read a good introductory book on …

One more thing, if you don't want your programming Linux distro to be devoid of systemd, there's an OpenRC spin for that. Thanks to Linux and the broader world of open source, this methodology becomes clearer and easier to implement on an almost daily basis, as new Linux-based innovations, like …

The list goes on. Although the terms free software and open source software are usually used more or less interchangeably, there are some subtle differences. Advocates of copyleft respond by pointing out that there is no such thing as absolute freedom. So, the FAT module contains a reference to the …

Until recently, most modems were 8 or 16 bit ISA cards. Free software is also very different from public domain software. There are times when controllers need to read or write large amounts of data directly to or from system memory. The device driver places bytes onto the queue, one …

There are editors, compilers and interpreters for nearly every language ever created, debuggers, parser generators, you name it. What exactly do the kernel and the C library provide? Whereas it had previously been the norm to assist colleagues and freely share ideas and software, such cooperation suddenly became forbidden and …

Sustainable technologies are about ensuring access to knowledge forever. Traditionally, all Unix programming was system-level programming. Critical mass will be reached when people are given a CD that they can install just as easily as Windows and will provide them with all the tools that they are accustomed to on …

By applying the foundational principals behind two factors, even the most techno-phobic and proprietary software entrenched small sized companies can painlessly move to Linux on the Desktop. It looks at each member of the operations pending queue (sem_pending) in turn, testing to see if the semphore operations will succeed this …

It interprets the commands the user types in and arranges for them to be carried out. The process of booting your Linux system can sometimes be easy and sometimes be difficult. Upgrading from one version to another is also painless. In addition to implementing the standard C library, glibc provides …

Hard links allow for complex filesystem structures with multiple pathnames pointing to the same data. You may need to go through several rounds of resubmission and additional feedback before your code is accepted, and in some cases it may be rejected. Share your personal experiences (good and bad) with Linux …