Demonstrate A Theoretical And Practical Understanding Of Key Components Of An Operating System

File and Directory Handling

Modern computing has witnessed the development of users to react to visual prompts regarding operating systems and control software. Command lines are regarded as the most often utilized in engineering and scientific environments to programming.

CLI or “Command Line Interface” is the text-based interface used for operating systems and software. This is used to allow users to react to visual prompts. This is done by typing command to interface and get a reply similarly.

The report includes methodologies of file and directory handling along with the process and task management commands. Then file system or disk management along with usage commands are demonstrated here. Lastly, CLIs and scripting are analyzed in this study.

Creating New Directory:

In order to create a directory within any current directory mkdir or make directory command used to be followed by the name of particular directory to be created.

Creating New File:

In order to develop  new file of any kind, “touch” command can be used  after by that filename. Type of data must be specified while creating filename extension. For example, the command to create empty HTML document named as an index is touch index.html (Beraldi 2017).

Deleting a File:

Files can be removed using rm command. Deleting directories needs additional instructions. A file can be deleted typing rm along with the name of a file to be deleted. To eliminate “contact.html” file the command to be used is rm contact.html.

Deleting a Directory:

The safety measures can be overridden by specifying command options. They are denoted as switches or flags. For instance, the default behaviour of rm command never permits to delete a directory and reveal what has been tried to remove any list (Read et al. 2016). However, -r option can be used to modify default behaviour of rm command where r is the abbreviation of recursive. Besides, the js directory and every file within the list can be removed by rm -r js.

Figure 1: “Usage of rm command”

(Source: Created by Author)

In order to transfer file or directory to new location, the mv command can be used. As a list is run, all their data and subdirectories go along with that. The mc command comes with a couple of arguments. Here, first case is the name of directory or file needed to be moved. Then, second one is the position where this is to be moved.

Deleting Files and Directories

While main.css is to be moved to style directory, the command to be issued is mv main.css styles.

Copying a File:

The command to be used for creating copy of file referred to as index.htm within present working directory is cp index.html contact.html. Here a copy of the file is named contact.html.

Copying a Directory:

While the directory is copied to another position, every files and subdirectory get copied with that. The command to copy styles directory is cp -r styles stylesNew. Here a copy of style directory is named stylesNew.

To describe the process management commands, the LINUX operating system is considered here.

Top command: 

This supplies information of the process existing at present. The first part of the information is an overview of the situation. The second part is organized in columns providing details of every person including their distinct reference number, priority, status and resource usage (Greenberg and Witten 2014).

Htop: 

It is same as top. Here, information is presented in more transparent format. One can select a specific process and then act on that with  htop display.

Ps command: 

This is to list running processes. One or other option must be specified to retrieve helpful data. It contains all processes over the system.

Command “ps –a” has been listing every processes on the system. “ps -a | grep mysqldwould” command, picking out mysqld process. For example, it takes place as one has a connection through a system to MySQL database.

Pstree: 

It is used to show tree diagram of processes displaying relationship existing between them (Pot’Vin, Miller and Smith 2014). Here, all process is created, spawned through additional or parent process in LINUX. It is to be noted that as something is altered for parent process, the child process also gets affected.

Figure 2: “Use of Pstree command”

(Source: Created by Author)

Who:

It shows a list of every user logged currently to LINUX system. As this occurs and operating system, one has a free hand in managing process as liked.

Kill:

This is to halt process along with high prejudice. Though in general sense, the function has been meant to send various kinds of signals. This has been allowing stopping groups or operations instead of having to completely halt or reboot the LINUX system. This is something that must also be appreciated by other users.

PID:

This is the process ID where systems assign numbers to every process such that it keeps tracks of that. This has been possible to possess various methods running with same names (Gorgolewski et al. 2017). However, PID is unique. This ID has not been equal every time a specific program is opened.

Moving Files and Directories

Session Name:

Till someone is at a network, this reads “Console”. It denotes that the process has been starting locally.

Session#:

Every session is assigned a number.

Mem Usage:

It provides useful information regarding an amount of memory in kilobytes could be processed has been used during running of Tasklist.

Status:

Providing current status of a process as “unknown”, “not responding”, “running” is the task of this command. It is helpful to seek hung processes. The unknown status refers to a normal process. However, “Not Responding” denotes a process that could be stopped.

User Name:

The user account below which process runs, Window runs various methods and systems. These accounts account NETWORK SERVICE, LOCAL SERVICE and SYSTEM that has been appearing. This has been coupled with local domain denoted by NT AUTHORITY.

CPU Time:

This indicates the total amount of cycle time of CPU that is utilized by process from the very first. It could be a more significant number as the computer is never turned off.

Window Title:

Windows has been displaying name of a process as it has been existing. This at many times helps in identifying what this program has been including (Giorgino 2014).

A quick way of opening disk management utility within any Windows version has been from Command Prompt. For this, a single short command is to be typed and disk management utility begins at any instant. The disk management is placed various layers deeper in maximum Windows version. Hence this has a quicker way to get access to this super-tool for hard-drives. Thus other storage devices have been coming very handy. Disk management command is similar in every Windows version. Hence instructions apply same for all versions of Windows (Huang and Cronk  2015). The steps to begin disk management from a command prompt in Windows are discussed hereafter.

In order to open disk management from different command prompt just a few seconds are taken. For Windows 10 or 8, the “Run” option is to be opened from the start menu or Application screen. For Windows 7 and Vista the “Start” button is to be clicked.

The command to be typed in Disk management is diskmgmt.msc. It is to be noted that opening disk management from the command prompt is needed as the command prompt program is opened. Besides, running an executable program such as diskmgmt.msc from search or run box has been accomplishing that same thing (Belmann et al. 2016). Further, diskmgmt.msc has never been a disk management command more than non-command-line tools that are executable is a command. The expression is only a run command for Disk Management program. Then, disk management opens quickly. Thus one can use disk management to alter drive letters, partitioning drives, formatting drive and so on.

Copying Files and Directories

However, for Windows 8 and 10, there is also a quicker method. Opening Disk management through “Power User Menu” is faster than its run command. In Windows 10, one can execute diskmgmt.msc from Cortana interface directly (Gureckis et al. 2016). This is efficient as anyone is used to use for performing commands already.  

Usage guide is developed initially through defining an arbitrary number of various sections. For example in description part, footer, examples, options list, synopsis, and so on. Every element contains an optional header and few contents. Every section should be a kind of material or optionList. The section data get passed to command line usage() rendering usage guide (Berman et al. 2014). Here inline ANSI formatting could be used elsewhere under section content using various formatting syntax.

On the operating systems supported by command line, the command called jEdit is passed through different arguments for controlling their behaviour. While opening various files from “command line marker” or the “line number” positioning could be specified like below.

$ jedit MyApplet.java +line:10

$ edit thesis.tex +marker:c

 Command line switches start with “-“. Few of them take a parameter. File who name starts with “-“ could be opened like

$ jedit — -myfile

Log=level:

One of the various other miscellaneous options is log=Level. It sets minimum log level to integers between 1 and nine. However, the default value is seven. Usage command:

This shows a brief usage of command line instead of starting jEdit. It is displayed as any invalid switch is specified.

Plugins	This enables to load plug-in. It has no impact while connecting to other instances through edit server.
Noplugins	It is used to disable the loading of a plug-in. It has no impact to connect to other instance through edit server.
Restore	This restores lastly opened files on startup. It is by default.
Norestore	It never restores previous files that are opened at startup.
Run=script	It is run on particular BeanShell script. Here one of the parameters is present on a command line.
Settings=dir	It is used to store user-specified settings in a directory named as dir. This is instead of default user.home/.jedit. A directory is created automatically as it never exists. It has no impact while connecting to other instance through edit server.
Nosettings	It starts jEdit instead of loading settings that are user-specified.
Startupscripts	It helps in running startup scripts. It is a default. It has no impact on connecting to other instances through edit server.
Nostartupscripts	It disables startup scripts. It has no impact while connecting to other examples through edit server.

background	First, jEdit is to be run in background mode. Here edit server continues to listen to client connections after every view is shut.
nobackground	Background mode must be disabled. It is by default. It has no impact while connecting to other examples through edit server.
GUI	An initial view must be opened. It is also the default. It has no impact while connecting to other examples through edit server.
Nogui	It never opens any initial view. It is only inaugurated as the first client connects. It could be utilized in assimilation with background switch.
Newplainview	It opens particular files in new understandable views.
Newview	It opens particular files to current view.
Quit	It is present in presently run editor sensor.

The command-line interface helps users to make interaction with personal computers through different typing commands. A computer shows prompt, user keys in command and presses return or enter. At previous days, every computer used to get connected to command-line interfaces (Bekker,  Nakamura and Kinjo 2016).

Features of the command-line interface include that command must be typed appropiately and in appropriate order. Otherwise, command might not perform properly. The different users who are experienced enough must be aware that those commands have been working properly instead of having to seek their way across menus (Mishra and Jangale 2014). Benefits of command driven programs are that they never run processing power or memory of the latest computer and must be running in machined with lower specifications. The command-driven programs never needed to be run on Windows platform. The command line interface are able to run various programs. Here, for instance, batch files can launch six programs to perform the tasks (Lefort et al. 2015). At many times, inexperienced users find command driven programs hard to use since there are various commands that are needed to be learnt. For instance, any common command-driven interface is the MS-DOS. MS-DOS command for displaying every file on the c:is :dir c:.

Process and Task Management commands

Figure 3: “ Using dir c: command”

(Source: Created by Author)

Scripting is a complicated sector which stores a bunch of commands to a file and executes them one-by-one. Firstly, from the home directory touch first.sh is to be typed.

A file is created and .sh at the end denotes that it has been a bash script. This has not been needed strictly (Ternent et al. 2014). However, it has been a useful convention adhering to. Then it is opened up for editing. This can be done by utilizing “vi” command as one has chops. One can open up a file in favourite text editor. The echo command can be considered here. For example the line “echo ‘hey world hey’” can be taken. It has been printing what they are asked to be (Walls 2016). However, in this case, it is meant to be meaningful. For executing the script the following expression can be typed on a command line.

bash first.sh

As someone proceeds with this, and any error is caught saying “permission denied”, indicates that a file with reading/write privilege is created that never have the permission of executing. This problem can be mitigated by typing chmod u+x first.sh

This command alters permissions on file provided. U+X indicates that the users are needed to ensure with execution privileges.

Thus scripting is an effective method save typing on a group of commands run together. Complex commands can be remembered (Jovic, Brkic and Bogunovic 2014). Hence there is no need to look up or risk of forgetting or specific syntax used every-time. Control structures such as case or loop statements help scripts to perform complicated tasks. Thus writing of these structures in this script makes that more convenient for typing and simpler in reading.

Conclusion: 

Various programs have been delivering an entirely new context under command line interface. Environment variables and user account have been providing context for command line interfaces. The report shows that command lines, on the other hand, have temporarily taken over every input and output. It has allowed users in interacting more with scripts, files, databases directly. Further, they have changed display and accept commands unavailable in regular command line interface. Commands have been available in proper CLI that has not been available in those interfaces. Command line skills have been helping to start learning about programs. Practicing and experimenting command lines can retain and develop what has been learned. More command line is used, more natural it turns to be. At present days, well-designed easy-to-use CLI is a mandatory feature for any stable backend software. Efficient CLI integrates into various automated processes seamlessly. Continuous development permits pre-configuring applications as the part of their environment installation. The continuous integration uses this application as part of the more prominent workflow.  Lastly, it must be understood that in the development process of CLI, none of the modifications from the side of GUI is necessary. As a CLI turns out to be functional, GUI calls merely the CLI commands.

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