Becoming familiar with Linux can result in a substantial financial savings because the software (both the operating system and the application programs) is available for free and because Linux can run on older and cheaper computers. In 1978, Kernighan and Ritchie wrote, "The C Programming Language," a book that is …

If the kernel handles the signals, it will do the default actions required for this signal. The target host that owns the IP address, responds with an ARP reply that contains its physical hardware address. First, arrow to the boot option that you want to modify, and then press the …

Its entries are also device_struct data structures. Copyright does not protect facts, discoveries, ideas, systems or methods of operation, although it can protect the way they are expressed. Remember that the shell is a program providing you with an interface to the Linux system. Binary compatibility is maintained across a …

As such it is possible to have two or more files and directories with the same name but letters of different case. I say somewhat, because the use of sed in conjunction with pipes is somewhat more comfortable (at least to this author) for substitution of text in files. Software …

Each filesystem is mounted to a specific location in the namespace, known as a mount point. For the old system timers the timer_active bit mask is check for bits that are set. NASA spacecrafts, Motorola cell phones, Google Android smart- phones and tablets, Amazon Kindle eBook readers, TomTom GPS navigation …

It can also be a Macintosh or almost any other type of computer. The overhead of symbolic links is minimal, but it is still considered a negative. Setting up TCP/IP connections is very different from setting up an amateur radio X.25 connection. Red Hat or Slackware) comes with …

awk is actually a programming language designed particularly for text manipulation, but it is widely used as an on-the-spot tool for administration. Notably, Linux is the fastest growing operating system released to date. Linux is a multiprocessing operating system, its objective is to have a process running on each CPU …

Processes are generally associated with a user's login group, not any of the supplemental groups. Sometimes the DMA channel for a device can be set by jumpers; a number of ethernet devices use this technique. In user space, Linux implements threads in accordance with POSIX 1003.1c (known as Pthreads …

The read/write heads are moved across the surface of the platters by an actuator. The Linux kernel, supporting both preemptive multitasking and virtual memory, provides every process both a virtualized processor and a virtualized view of memory. Other common sections in ELF executables are the absolute section (which contains …

The IDE disks are controlled by the IDE controller chip and the SCSI disks by the SCSI disk controller chips and so on. Press the B key to boot the system using the new values. The source code for Linux is under copyright by its many individual authors, and licensed …

The new vm_area_struct structure is put into the list of vm_area_struct pointed at by the shmid_ds. Some such devices are partionable, which means that they can be divided up into multiple filesystems, all of which can be manipulated individually. Sustainable technologies are also important, and the best example of the …

Over the years, Unix systems have supported a handful of different special files. Like so many others I have always thought that one of the greatest attributes of Linux is its diversity of choice, but there are those outside of the Linux world that see this as a negative. Quite …

Where Linux has shown a significant advantage over proprietary Unix is in its availability across a vast number of hardware platforms and devices. Another type of open source license is the artistic license, which ensures that the source code of the program is freely available yet allows the original author …

In addition to steadfast stalwarts like Fortran and C/C++, many scripting and other computer languages are at home on (or were even designed to work best with) Linux. The Linux kernel must be able to interact with them in standard ways. It is the scheduler that must select the …

The character % introduces a job name. At kernel initialization time, the address families built into the kernel register themselves with the BSD socket interface. Both are very different from proprietary software (also commonly called commercial software), which is software that is controlled by a company or an individual. Source code …

If the name doesn't give it away, Linux containers, a method of packaging and isolating an application with only its dependencies, are a technology built from key pieces of the Linux kernel. Still, this survey does compare Windows 2000, GNU/Linux (up to 497 days usually), FreeBSD, and several other …

The receiving IP layer uses that protocol identifier to decide which layer to pass the received data up to, in this case the TCP layer. Kernel modules, like the kernel itself, are usually written in C. When Linux fixes up that page fault it finds the vm_area_struct data structure describing …

Windows implementation is very high-level. In the event of a total implosion, much of the software can be reinstalled with batch files made up of multiple sudo apt install statements. Ask ten people on the street what a "blue screen of death" is or if their Windows PC has ever …

First of all the DMA controller knows nothing of virtual memory, it only has access to the physical memory in the system. If they will then it removes the sem_queue data structure from the operations pending list and applies the semaphore operations to the semaphore array. Institutions that rely solely …

When a command terminates on a fatal signal, bash uses the value of 128+signal as the exit status. Let's look at creating an image file so we can start a container which we created. Much of enterprise IT's excitement is focused on advancements at the application level (and rightly …

Users of closed source operating systems must report the bug to the manufacturer and wait for the manufacturer to develop, test, and release a solution to the problem, known as a hot fix. Unlike the MINIX filesystem before it, ext could address up to 2GB of storage and handle 255-character …

This might be a bit of a controversial statement, but I've not seen any Linux GUIs that are quite as good as Windows. In 1978, Kernighan and Ritchie wrote, "The C Programming Language," a book that is today as it was 20 years ago: THE book on C programming. Like …

Linux and other open source projects built on top of it have helped to drive the a standardization of IT, allowing for more interoperability across the world's business environment. Many of the devices you own probably, such as Android phones, digital storage devices, personal video recorders, cameras, wearables, and more …

Dynamically loading code as it is needed is attractive as it keeps the kernel size to a minimum and makes the kernel very flexible. For DOS formatted disks, those formatted by fdisk, there are four primary disk partitions. Linux is that power. The originator of the request, the client, creates …

When provided with a relative pathname, the kernel begins the pathname resolution in the current working directory. Linux systems always have a root filesystem. I've been in Free Software for a few years now and learned a ton from it. Modularity is common in nature, and its application to man-made …

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 that platform - mostly this means a Microsoft Office equivalent. If, however, that company transitions to Linux …

There are various other shell interpreters available, such as Korn shell, C shell and more. The first method is most often the easiest, as long as your system UEFI boot manager allows you to disable the secure boot feature. For the operating system to accomplish this, it must contain the …

Newbies can directly cat crontab file to see the syntax in case they forget it. The API merely defines the interface; the piece of software that actually provides the API is known as the implementation of the API. There are editors, compilers and interpreters for nearly every language ever created …

A security breach unnoticed by the vendor can easily be exploited by the wrong person. That aside, FIFOs are handled almost exactly the same way as pipes and they use the same data structures and operations. Although there are numerous distributions available, most of the older, well-known distributions are good …

The code is supplied on CDROMs or other media with the executable program and/or it is made available for downloading from the Internet. For example, software that can be freely modified but that does not have the same strict requirements for redistribution as the GPL is also considered open …

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 many of these devices while allowing for more innovation on top of it. Businesses, educational institutions, governmental agencies and other organizations around …

For example, when we add a user named "paul," Linux creates a directory /home/paul. It is just the way Linux works that makes it a secure operating system. insmod copies the module into the allocated space and relocates it so that it will run from the kernel address that …

Written originally for the Digital Equipment Corporation (DEC) family of PDP microcomputers, this most popular of multi-user, general-purpose operating systems has taken over roles in all areas of computing -- even those once held by mainframes. Although, there's no rocket science in it. Because of the rarity of malware threats, there …

The IP protocol is a transport layer that is used by other protocols to carry their data. One interesting feature it has is that every instruction is conditional. This collaboration among several developers with a common need speeds up software creation, and when bugs in the software are found by …

All Unix versions and workalikes, including Linux, communciate between devices (computers, printers, cash registers, etc) using TCP/IP. Where Linux has shown a significant advantage over proprietary Unix is in its availability across a vast number of hardware platforms and devices. As both communities have matured over the past decade …

The instructions executed by the processor are very simple; for example ``read the contents of memory at location X into register Y'. The target host that owns the IP address, responds with an ARP reply that contains its physical hardware address. Staff and students in the school have the tcsh …

The API user (generally, the higher-level software) has zero input into the API and its implementation. The file position starts at zero; it cannot be negative. Processes are generally associated with a user's login group, not any of the supplemental groups. (Even of the large corporately-funded developer base, many have …

There are many ways to make money, so why choose a method that requires investing just as much time and effort into making software that lots of people want to use as trying to prevent the usage of said software? Most shells offer a similar set of internal commands, but …

The exact wording of a recipe as it is written by its author is protected under copyright law, but the information itself (i.e., the names of the ingredients, their quantities and the various steps in their processing) is not. Even so, if a process executes until it waits then …

Mostly Linux kernel modules are device drivers, pseudo-device drivers such as network drivers, or file-systems. The IP protocol layer itself uses many different physical media to transport IP packets to other IP hosts. Software and other creative works enter the public domain only if the author deliberately surrenders the copyright …