DOS and Unix are operating systems where DOS is supported for only x86 computer systems and Unix supports for all systems. DOS is a single user operating system whereas Unix is a multi-user operating system. DOS was developed for personal computers (x86 type) and embedded systems. Unix was developed in AT &T Bell University which is primarily used in servers. What is DOS? DOS is the short form of Disc Operating system. 86-DOS was developed by Tim Patterson in 1980. Later Microsoft bought this and released MS-DOS in 1981. It is a single processing operating system that can be run ... Read More

Linux is a popular operating system among computer enthusiasts. It is a free and open operating system. Shells are the screens that we utilize to control an operating system. Shells are CSH and BASH. Shells act as a channel for communication between programmers and the device. We issue orders and obtain results. The C-shell was named after the C programming syntax. One of its many benefits is the ability to regulate jobs. It may be accessed via script shell command runner and interactive shell login. It might not be easy to use at times. Bash is a shell software similar ... Read More

Introduction In a Unix-based operating system, it is important to manage the resources consumed by processes to ensure that the system runs smoothly. If a process consumes too many resources, it can cause the system to become slow or unresponsive. In some cases, it can even cause the system to crash. Therefore, it is important to be able to limit the resources that a process can consume. There are several ways to limit the resource consumption of processes in Unix. One way is to use the ulimit command, which allows you to set limits on the resources that a process ... Read More

The dispute between IBM and SCO began in March 2003, when SCO Group, a Utah-based firm, filed a lawsuit against IBM, claiming that IBM had broken the license agreement for AIX (IBM's in-house version of Unix) that it had signed with AT&T and that SCO now controlled. By offering AIX to other companies, SCO Group said IBM was in breach of contract. More than a billion dollars were sought in damages for the complaint, which also alleged illegal competition and a violation of the contract. Just two months after filing suit, SCO claimed to have found more UNIX code ... Read More

Tmux is a terminal multiple for Unix OS. It provides multiple terminal sessions to its users. It is used when we are using cloud-based services (like Azure, AWS) for the creation of separate terminals for different remote users.While working with web services, one needs to create an EC2 instance on the webserver provided by the company to work on it by creating a session.Now, let’s see the steps of working on a UNIX (Ubuntu) webserver.Step 1 − Write/copy the IP address of your AWS console and download the key file from the console. You will get these from your vendor ... Read More

Unix PipesUnix Pipes are used in inter-process communication. A pipe as name suggests provides a unidirectional flow of information. Data flows from one end to another.Message QueuesMessage queue allows to share messages by a sender process to another process (es). A message queue is implemented as a linked list of messages and stored within kernel. Each message has a unique message queue identifier. The kernel keeps a record of message queues present in the system.The following are some of the important differences between Unix Pipes and Message Queues.Sr. No.KeyPipeMessage Queue1ConceptThe pipe is the Unix IPC form to provide a flow ... Read More

String has a time zone, and there is usually no need to set a default time zone. But when it needs to be printed, the default time zone can be set explicitly. Below is the code to do the same −Default timezoneExample Live Demoecho date_default_timezone_get();OutputThis will produce the following output −UTCWhen timezone is specifiedExample Live Demoecho date("Y-m-d H:i:s",strtotime("1/1/2020 00:00:00 America/Los_Angeles"));OutputThis will produce the following output −2020-01-01 08:00:00 Another way of specifying timezoneExample Live Demoecho date("Y-m-d H:i:s",strtotime("1/1/2020 00:00:00"));OutputThis will produce the following output −2020-01-01 00:00:00

The hard disk in a computer is formatted with specific file system so that the operating system can read and write into it. For UNIX based systems we have various type of file systems. In this article we will see how to format a new partition in hard disk with ext4 file system.Available Filesystem typesFirst we see what are the different file systems available for the current operating system. The below command lists all those file systems.$ ls -1 /sbin/mkfs*Running the above code gives us the following result −/sbin/mkfs /sbin/mkfs.bfs /sbin/mkfs.cramfs /sbin/mkfs.ext2 /sbin/mkfs.ext3 /sbin/mkfs.ext4 /sbin/mkfs.ext4dev /sbin/mkfs.fat /sbin/mkfs.minix /sbin/mkfs.msdos /sbin/mkfs.ntfs /sbin/mkfs.vfatLook ... Read More

The fuser utility in Linux is a very smart Unix utility. As the name suggests, it offers knowledge about file user or the process that is currently utilizing the file or directory. This article explains about – Frequently used examples of ‘fuser’ Command in Linux.To get the more information about fuser, use the following command –$ fuserThe sample output should be like this –Usage: fuser [-fMuvw] [-a|-s] [-4|-6] [-c|-m|-n SPACE] [-k [-i] [-SIGNAL]] NAME... fuser -l fuser -V Show which processes use the named files, sockets, or filesystems. -a, --all             display unused files ... Read More

Webmin is a web-based interface for system administration in Unix. Using any modern web browser, you can setup user accounts, Apache, DNS, file sharing and much more. Webmin removes the need to manually edit Unix configuration files like /etc/passwd and lets you manage a system from the console or remotely. This article explains you about how to install Webmin on Ubuntu.To install Webmin open /etc/apt/sources.list  file as shown below-# sudo nano /etc/apt/sources.listThe sample output of the file should be like this –# deb cdrom:[Ubuntu 14.04.4 LTS _Trusty Tahr_ - Release amd64 (20160217.1)]/ trusty main restricted # See http://help.ubuntu.com/community/UpgradeNotes for ... Read More