Typically, it is mounted automatically by the system, but it can also be mounted manually using a command such as: Mount options The proc filesystem supports the following mount options: This is the traditional behavior, and the default if this mount option is not specified. This makes it impossible to learn whether any user is running a specific program so long as the program doesn't otherwise reveal itself by its behavior.
Read errors of unreliable, one-dimensional bar codes often caused interruptions in industrial production, prompting companies like Toyota and its subsidiary Denso Wave to develop as early as a new code for acquiring stock data.
The new matrix bar code was designed to store more information than the traditional bar code and to stay legible, even if the label was dirty, wrinkled, or partially destroyed.
The quick response code, or QR code, comprises a matrix of square dots instead of the usual lines. Measuring up to by dots, the QR code encodes up to 4, characters, compared with a bar code that encodes just Thanks to numerous free reader apps for smartphones, QR codes have gained in popularity in recent years.
Posters, catalogs, magazines, business cards, and even television screens display the small squares, offering additional information or URLs for microsites. Data Grabber If you want to encode your address into a QR code for a business card, you could try one of the many services on the Internet.
However, restrictions typically apply. For example, some services allow only QR codes in a certain size or in limited quantities.
Fortunately, several QR code tools can help you avoid these problems in Linux. The quickest way to create a QR code is with the Qrencode command-line utility.
Any major distribution can install Qrencode via the package manager. The generated QR code ends up in the qrcode. If you have at least version 3. Each corresponds to a dot. In the QR code image, the software creates a white border the width of one dot.
This facilitates the process of deciphering the code for programs or the smartphone later on.
If desirable, you can increase or decrease the edge with the -m parameter; in the following example the border width would be 10 code pixels: By default, Qrencode draws every black dot three by three pixels.
The program creates a slightly smaller QR code with quite a wide margin with the following command: If you are creating EPS images, the only parameter available is -m; -s moves the entire QR code out of the image in this case.
To control the resolution of PNGs further, use the -d parameter to define the dpi. Tolerance Besides the specified data, the QR code contains additional error correction information. If a portion of the image is damaged, it allows you to reconstruct the missing or illegible data.
The more additional information the QR code contains, the more heavily damaged it can be without becoming useless. Increasing the error tolerance increases the size of the image because you need more black dots Figure 3. Both QR codes contain the text Hello World!
The QR code standard thus uses four levels of error correction:In Unix-like operating systems, a device file or special file is an interface to a device driver that appears in a file system as if it were an ordinary heartoftexashop.com are also special files in MS-DOS, OS/2, and Microsoft heartoftexashop.com special files allow an application program to interact with a device by using its device driver via standard input/output system calls.
This tutorial is for software developers using IBM/Rational Clearcase for change management (CM) on Linux. Unlike many of the text file based CM systems like RCS and CVS, Clearcase used its Multi Version File System (MVFS) to hold various revisions of a file and control locking of files checked out to a .
Linux Foundation smushes two smaller projects together to form Open Networking Automation Platform The Linux Foundation announced today that it had combined open source ECOMP and the Open.
The reason why Linux and open source will always be more secure than Windows is because you can build advanced security right in. This guide’s going to show you how to do that. SUSE Linux Enterprise Server is a highly reliable, scalable, and secure server operating system, built to power mission-critical workloads in both physical and virtual environments.
Fedora Core and Red Hat Linux CD Installation, Version Upgrade, Configuration and Basic Administration.
Kernel Parameters. The following is a consolidated list of the kernel parameters as implemented (mostly) by the __setup() macro and sorted into English Dictionary order (defined as ignoring all punctuation and sorting digits before letters in a case insensitive . In Unix-like operating systems, a device file or special file is an interface to a device driver that appears in a file system as if it were an ordinary heartoftexashop.com are also special files in MS-DOS, OS/2, and Microsoft heartoftexashop.com special files allow an application program to interact with a device by using its device driver via standard input/output system calls. Ubuntu Linux is a Debian derivative distribution of Linux aimed at being fairly easy for someone new to the Linux environment - the ordinary user - and having a somewhat different and thereby hopefully faster version release process. Their motto is "Linux for Human Beings", and Canonical Ltd. in the UK supports them professionally. This image was inspired by the IRC chat clients found in the.
This tutorial covers the installation and/or upgrades, configuration and basic administration of Red Hat Enterprise Linux , Fedora Core .