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 …

The Graphical User Interface is much easier and I can already do most of what I need there." To a certain extent you would be right, and by no means am I suggesting you should ditch the GUI. Networking the critical aspects of a city, from manhole covers and traffic …

The smallest addressable unit on a block device is the sector. With the connection established both ends are free to send and receive data. When it is started up, usually at system boot time, it opens up an Inter-Process Communication (IPC) channel to the kernel. At kernel initialization time, the …

Its own Software Center has tons of free applications that make it a great Linux OS for programming. Another good example is the PCI bus which allows each device (for example a graphics card) to be accessed independently. Apart from the ability of a loaded module to crash the operating …

Keep in mind that these are only conventions---not rules. It is time for the opening of the tools that will be needed to build this new age. Numerous such standards exist but, technically speaking, Linux does not officially comply with any of them. When using Linux, you often face configurations …

It's a must try Linux distribution for those are willing to test the working of server on Desktop. But all things come to an end eventually. Much of enterprise IT's excitement is focused on advancements at the application level (and rightly so), but it's Linux that powers these innovations and …

The umbrella of system programming often includes kernel development, or at least device driver writing. The Linux kernel is the core of the operating system. If user space were allowed to manipulate directories without the kernel's mediation, it would be too easy for a single simple error to corrupt the …

If you're interested in writing code for the Linux kernel itself, a good place to get started is in the Kernel Newbies FAQ, which will explain some of the concepts and processes you'll want to be familiar with. This chapter describes how the Linux kernel manages the physical devices in …

Binary compatibility is maintained across a given major version of glibc, at the very least. Does it support my critical applications? Linux aims toward POSIX and SUS compliance. Of course, most system calls have only a couple of parameters.

Getting Enlightenment to work with a dual screen monitor

Very small company leadership, with less than ten personnel, often incorrectly assume that interpersonal issues and technical decisions are not correlated at all. The kernel does not impose any restrictions on concurrent file access. Each command comes with a manual page which can be used to learn about its function …

Some operating systems, such as VMS, provide highly structured files, supporting concepts such as records. Linux maintains the set of registered block devices as the blkdevs vector. A process is also associated with various system resources, which are arbitrated and managed by the kernel. Its own Software Center has tons …

To me, that is the distasteful and damaging side of the Linux world. Another difference, particularly as compared to a Windows system is that many Linux users prefer to compile their applications from source code. While Linus hacked away on the fledgling Linux kernel, Remy Card worked on the first …

I am a composer, and one of the biggest hurdles for me in switching to exclusively Free Software was my sheet music typesetting software. The way that FIFOs are opened is a little different from pipes. The exact mechanism varies from architecture to architecture. Linux itself is actually just the …

and insert it as the first line of your script. Arch Linux, the favorite Linux distribution of die-hard Linux enthusiasts, comes with Linux kernel and package manager. Linux keeps looking through the pending list from the start until there is a pass where no semaphore operations can be applied and …

Also, most OSS does not retire after a short period of time because collaborative open source development results in constant software improvement geared to the needs of the users. This software universe had been going on behind my back for years. Files may reside in any of these directories. There …

Even so, most software developers, even those who have grown up during this venerable "Linux revolution" have at least heard of Unix. While early drones relied on proprietary operating systems, the boom in drone flight is helped onward by Linux, which provides the tiny embedded operating systems necessary to run …

You can easily see the exported kernel symbols and their values by looking at /proc/ksyms or by using the ksyms utility. As the writing process writes to the pipe, bytes are copied into the shared data page and when the reading process reads from the pipe, bytes are copied …

This is one of those arguments that sounds good superficially but which is not borne out by the evidence. If the thief runs, he/she probably won't get caught, and it is a quick way to make some extra cash. If you've always wanted to learn programming, whether you want …

The four bytes are written as four decimal numbers in the 0-255 range, separated by dots. In this case the waiting process will be suspended and another, more deserving process will be chosen to run. The most difficult part of the installation process is, without a doubt, partitioning the hard …

In the Linux world, a large number of users will always prefer to compile applications from source, rather than using an installer package. While there are other options, the most common scripting language is Bash. It's a must try Linux distribution for those are willing to test the working of …

For example when user data is being written to the hard disk. ARP is not just restricted to ethernet devices, it can resolve IP addresses for other physical media, for example FDDI. One more thing, if you don't want your programming Linux distro to be devoid of systemd, there's an …

Processes are allowed to do non-blocking reads (it depends on the mode in which they opened the file or pipe) and, in this case, if there is no data to be read or if the pipe is locked, an error will be returned. When processes are deleted, as they exit …

Sed is the Spanish word for thirst, Though you may thirst (or hunger, or whatever) for an easier way to do things, its name did not derive from there. As of April 2008, Linux had fewer than 100 known viruses, whereas Windows had more than 1,000,000 known viruses …

The platters are attached to a central spindle and spin at a constant speed that can vary between 3000 and 10,000 RPM depending on the model. These applications are not going away anytime soon. When there are no more characters left to read, the device returns end-of-file (EOF). The …

The name is an acronym for the 'Bourne-Again SHell'. Track 0 is the outermost track and the highest numbered track is the track closest to the central spindle. If no output_file is supplied, output goes to stdout. The maximum file length, as with the maximum file position, is bounded only …

The IDE disks are controlled by the IDE controller chip and the SCSI disks by the SCSI disk controller chips and so on. The Raspberry Pi, popular with hobbyists and enthusiasts, is Linux-driven and has opened the door for an entire spectrum of IoT devices running Linux. The timer bottom …

To help bring order to chaos, standards groups codify system interfaces into official standards. Many of the best Linux experts are self taught and do not possess a single computer certification. It needs to be able to support what an IT team requires in the moment and in the future …

The IP protocol layer itself uses many different physical media to transport IP packets to other IP hosts. If you look at the output of lsmod, you will see that each module has a count associated with it. Until recently, most modems were 8 or 16 bit ISA cards. While …

True, they are often needed for one project or another and can be well worth the cost, but for a beginner or a learner -- and for many professionals -- free software is simply irreplaceable. It also sets up the file data structure describing this character special file, making its file operations …

If a developer needs a VM or if IT Ops needs to provision a server, they expect to do so quickly and painlessly; Linux's scalability allows for this rapid provisioning, as does its lack of cost-prohibitive licensing. The Linux command line offers a wealth of power and opportunity. A good …

The major identifier for the primary IDE controller is 3 and is 22 for the secondary IDE controller. The GPL subsequently became by far the most widely used license for free software. The analogy is also frequently made with recipes for cooking food. Multiple processes are free to read from …

insmod physically writes the address of the symbol into the appropriate place in the module. Aliases are expanded when the function definition is read, not when the function is executed, because a function definition is itself a compound command. Once connection has been made, any of the (usually) several browsers …

Although directories are treated like normal files, the kernel does not allow them to be opened and manipulated like regular files. Any ethernet frame transmitted to that address will be received by the addressed host but ignored by all the other hosts connected to the network. Some operating systems, such …

By calling bash executable binary explicitly, the content of our file date.sh is loaded and interpreted as Bash Shell Script. For most users, LILO works best. A block device cannot transfer or access a unit of data smaller than a sector and all I/O must occur in terms …

However, they seem to be forgetting that, while some action we make won't directly influence everybody, every action we make affects somebody. It is vital that we keep a philosophical approach so that our beliefs stand behind our actions. This instruction causes a switch into kernel space, the protected realm …