The Linux system call uses the write routine pointed at by the file data structure describing this pipe. If you have a /etc/cron.allow file, this supersedes cron.deny (ie, cron.deny is ignored) and allows only those listed in it to use cron. The only rule is that …

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 …

The new module also exports symbols to the kernel and insmod builds a table of these exported images. Notably, Linux is the fastest growing operating system released to date. More importantly, Linux strives to behave in accordance with POSIX and SUS requirements. WinModems lack some basic hardware on the modem …

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 …

As you can see, by use of scripting, any shell interaction can be automated and scripted. A typical Linux distribution includes the Linux kernel, but it also contains many application programs and tools. The device identifier for the first partition of that disk (/dev/hdb1) is (3,65). Knowledge and …

The inode is both a physical object, located on disk in Unix-style filesystems, and a conceptual entity, represented by a data structure in the Linux kernel. It may not be the best choice for word processing (or maybe it is -- read on), but many see it as an "ISP in …

For example, you cannot unload the VFAT module if you have one or more VFAT file systems mounted. In fact, there is no difference between command execution directly via terminal or within a shell script apart from the fact that the shell script offers non-interactive execution of multiple commands as …

This modest computer's official Raspbian OS comes loaded with tons of programming tools, connector pins, and other useful ports. To accomplish more complex tasks, tools would simply be connected together, using pipes. For self study it can be useful to have a good introductory book. Organizations today do not need …

A server is a computer with an operating system that is configured to allow other computers to connect to it from across a network. Keep in mind that these are only conventions---not rules. Setting up TCP/IP connections is very different from setting up an amateur radio X.25 connection …

You need to start from the ground up, choose components, and build a customized operating system that could easily become a great Linux distro for programming and other development purposes. Each filesystem is mounted to a specific location in the namespace, known as a mount point. One who bases his …

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 …

Like the virtual filesystem, Linux abstracts the socket interface with the BSD socket layer being concerned with the BSD socket interface to the application programs which is in turn supported by independent address family specific software. This is especially important if a particularly vital application does not yet exist for …

This integration would result in efficient administration. Filesystems usually exist physically (i.e., are stored on disk), although Linux also supports virtual filesystems that exist only in memory, and network filesystems that exist on machines across the network. Most processes consist of only a single thread; they are called single-threaded …

They will not begin with a slash. In general, failing to agree with the standards is considered a bug. Not all four entries in the partition table have to be used. None other than the system call handler!

Scan the results of parameter expansion

At that time a new generation of computers with proprietary operating systems was introduced, and their vendors required that users sign non-disclosure statements in order to obtain copies of the operating systems. Software running on the CPU must be able to read and write those controlling registers. (To be a …

The other is part of OpenOffice, a full-fledged office productivity suite that is comparable to and compatible with Microsoft Office. Oracle Corporation, another heavyweight in the DBMS industry, recently announced it would be creating a Linux compatible Oracle. Likewise, some minimal restrictions are necessary for free software, namely the GPL …

In general, there is a tendency for advocates of the term term free software to emphasize the ideological aspects of software, including the ethical or moral aspects, and they view technical excellence as both a desirable and an unavoidable by-product of their ethical standards. The shell learns immediately whenever a …

For some small business leaders I've consulted, the human factor is either a notion to be rejected or ignored. For most users, LILO works best. Kerneld is just an agent of the kernel, scheduling work on its behalf. Not often are our basic rights thought of in the context of …

Whenever a VFS inode representing a character special file is created, its file operations are set to the default character device operations . For this reason, it is referred to as Open Source Software (OSS). Rather than having to satisfy a set of needs laid out by a single department head …

Installation can take a while, depending on the speed of the computer and the options selected. Apart from the ability of a loaded module to crash the operating system by being badly written, it presents another danger. Each approach has its advantages and disadvantages. If your memory is like mine …

The UEFI boot manager boots the mini-bootloader, then, in turn, it boots the standard Linux bootloader image. 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 …

Why make it easier for them. However, in most cases it is closed source (i.e., the source code is kept secret), and there are often restrictions on the use of the executable version. If all of the semaphore operations would have succeeded and the current process does not need …

In a multiprocessing system many processes are kept in memory at the same time. The kernel does not impose any restrictions on concurrent file access. This software universe had been going on behind my back for years. Just maybe that crash you reported will save some people from a major …

Processes that are started at boot time usually run as root or nobody. As a Linux user today you have all the means of getting to know your system inside out, but it is no longer necessary to have that knowledge in order to make the system comply to your …

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 …

Therefore, mastering Linux for configuring and maintaining servers is a must to have skill for any technological entrepreneur who operates end-to-end applications. 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 …

It is vital that there is an uninterrupted stream of knowledge, and that information is not held back for personal benefit at the cost of others. Most of the time you will be issuing commands. Anyone can join the Linux community by participating in and contributing to this mailing list …