There are no set boundaries or any limitations. The visibility and easy access to the source code, which I mentioned earlier, can also be a double-edged sword as bad-intentioned people can find vulnerabilities and leave backdoors for future exploits. Processes begin life as executable object code, which is machine-runnable code …

Every process except the first has a parent. So, if the operation value is 2, then -2 is added to the adjustment entry for this semaphore. It is as old as computers themselves. What does this mean to you?

At the Linux terminal with Firejail

Each device driver tells the operating system how to use that specific device. The process tree is rooted at the first process, known as the init process, which is typically the init program. By and throughout the 1990s, you could find MINIX installations thriving in universities worldwide-and a young Linus …

In commercial UNIX development houses, the entire system is developed with a rigorous policy of quality assurance, source and revision control systems, documentation, and bug reporting and resolution. This was the beginning of techniques such as license keys. This is true even if the device is a modem being used …

From the filename, the kernel obtains the inode number. The command cd may be run without a location as we saw in the shortcut above but usually will be run with a single command line argument which is the location we would like to change into. A block device cannot …

But Unix has a much richer history beyond those bearded C programmers from the 1970s. By the time I was done, I had actually forgotten how to use my old piece of proprietary garbageware. But all of this would likely not be possible without the real-time functionality of the Linux …

Whereas pwd is just run by itself with no arguments, ls is a little more powerful. If this execution fails because the file is not in executable format, and the file is not a directory, it is assumed to be a shell script, a file containing shell commands. They are …

In this way, the Internet acts as the glue that binds together Linux developers in particular and OSS developers in general. Built in to the structure of the command-line environment are dozens of commands and several text-based help systems. Now, imagine that the execution of all the above commands is …

To make sure that even in a dual boot scenario office staff do not cling to their past desktop but acclimate quickly to the new desktop simply requires a "conversion plan." All of the employees know they will have a dual boot system that is fully functional for the first …

Interestingly, the ability of bash scripting is also one of the most compelling reasons why programmers prefer using Linux OS. Linux has two types of system timers, both queue routines to be called at some system time but they are slightly different in their implementations. Most open source Internet tools …

Of course, most system calls have only a couple of parameters. So now you are probably starting to see that we can refer to a location in a variety of different ways. The saved uid stores the original effective uid; its value is used in deciding what effective uid values …

Because Linux has such a large number of contributors from across multiple decades of development, contacting each individual author and getting them to agree to a new license is virtually impossible, so that Linux remaining licensed under the GPLv2 in perpetuity is all but assured. Linux tracks the usage of …

The issues with the Diebold [2] voting systems in the US is testament [3] to the need for transparent systems that are trustworthy. In the above example, the vfat and msdos modules are both dependent on the fat module and so it has a count of 2. For Linux, a …

For those companies, Linux supports most UNIX commands and standards, which makes transitioning to Linux very easy because the company likely would not need to pur- chase additional software or retrain staff. Also, the kernel compilation process is not as verbose in the 2.6 kernel series. A question that …

Where does the bash fit in? The keyboard, mouse and serial ports are controlled by a SuperIO chip, the IDE disks by an IDE controller, SCSI disks by a SCSI controller and so on. Linux is believed to comply with POSIX.1 and SUSv3, but as no official POSIX or …

In addition to the real uid, each process also has an effective uid, a saved uid, and a filesystem uid. The terminal in Linux is a wild card. Whereas sockets communicating over the Internet might use a hostname and port pair for identifying the target of communication, Unix domain sockets …