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What is Syntax Analysis?

Syntax Analysis is a second phase of the compiler design process in which the given input string is checked for the confirmation of rules and structure of the formal grammar. It analyses the syntactical structure and checks if the given input is in the correct syntax of the programming language or not.

Syntax Analysis in Compiler Design process comes after the Lexical analysis phase. It is also known as the Parse Tree or Syntax Tree. The Parse Tree is developed with the help of pre-defined grammar of the language. The syntax analyser also checks whether a given program fulfills the rules implied by a context-free grammar. If it satisfies, the parser then creates the parse tree of that source program. Otherwise, it will display error messages.

Syntax Analyser Process

In this tutorial, you will learn

Why do you need Syntax Analyser?

Check if the code is valid grammatically

The syntactical analyser helps you to apply rules to the code

Helps you to make sure that each opening brace has a corresponding closing balance

Each declaration has a type and that the type must be exists

Important Syntax Analyser Terminology

Important terminologies used in syntax analysis process:

Sentence: A sentence is a group of character over some alphabet.

Lexeme: A lexeme is the lowest level syntactic unit of a language (e.g., total, start).

Token: A token is just a category of lexemes.

Keywords and reserved words – It is an identifier which is used as a fixed part of the syntax of a statement. It is a reserved word which you can’t use as a variable name or identifier.

Noise words – Noise words are optional which are inserted in a statement to enhance the readability of the sentence.

Comments – It is a very important part of the documentation. It mostly display by, /* */, or//Blank (spaces)

Delimiters – It is a syntactic element which marks the start or end of some syntactic unit. Like a statement or expression, “begin”…”end”, or {}.

Character set – ASCII, Unicode

Identifiers – It is a restrictions on the length which helps you to reduce the readability of the sentence.

Operator symbols – + and – performs two basic arithmetic operations.

Syntactic elements of the Language

Why do we need Parsing?

A parse also checks that the input string is well-formed, and if not, reject it.

Following are important tasks perform by the parser in compiler design:

Helps you to detect all types of Syntax errors

Find the position at which error has occurred

Clear & accurate description of the error.

Recovery from an error to continue and find further errors in the code.

Should not affect compilation of “correct” programs.

The parse must reject invalid texts by reporting syntax errors

Parsing Techniques

Parsing techniques are divided into two different groups:

Top-Down Parsing,

Bottom-Up Parsing

Top-Down Parsing:

In the top-down parsing construction of the parse tree starts at the root and then proceeds towards the leaves.

Two types of Top-down parsing are:

Predictive Parsing:

Predictive parse can predict which production should be used to replace the specific input string. The predictive parser uses look-ahead point, which points towards next input symbols. Backtracking is not an issue with this parsing technique. It is known as LL(1) Parser

Recursive Descent Parsing:

This parsing technique recursively parses the input to make a prase tree. It consists of several small functions, one for each nonterminal in the grammar.

In the bottom up parsing in compiler design, the construction of the parse tree starts with the leave, and then it processes towards its root. It is also called as shift-reduce parsing. This type of parsing in compiler design is created with the help of using some software tools.

Common Errors that occur in Parsing in System Software

Lexical: Name of an incorrectly typed identifier

Syntactical: unbalanced parenthesis or a missing semicolon

Semantical: incompatible value assignment

Logical: Infinite loop and not reachable code

A parser should able to detect and report any error found in the program. So, whenever an error occurred the parser. It should be able to handle it and carry on parsing the remaining input. A program can have following types of errors at various compilation process stages. There are five common error-recovery methods which can be implemented in the parser

In the case when the parser encounters an error, it helps you to take corrective steps. This allows rest of inputs and states to parse ahead.

For example, adding a missing semicolon is comes in statement mode recover method. However, parse designer need to be careful while making these changes as one wrong correction may lead to an infinite loop.

In the case when the parser encounters an error, this mode ignores the rest of the statement and not process input from erroneous input to delimiter, like a semi-colon. This is a simple error recovery method.

In this type of recovery method, the parser rejects input symbols one by one until a single designated group of synchronizing tokens is found. The synchronizing tokens generally using delimiters like or.

Compiler corrects the program by inserting or deleting tokens. This allows it to proceed to parse from where it was. It performs correction on the remaining input. It can replace a prefix of the remaining input with some string this helps the parser to continue the process.

Error production recovery expands the grammar for the language which generates the erroneous constructs. The parser then performs error diagnostic about that construct.

The compiler should make less number of changes as possible while processing an incorrect input string. Given incorrect input string a and grammar c, algorithms will search for a parse tree for a related string b. Like some insertions, deletions, and modification made of tokens needed to transform an into b is as little as possible.

A grammar is a set of structural rules which describe a language. Grammars assign structure to any sentence. This term also refers to the study of these rules, and this file includes morphology, phonology, and syntax. It is capable of describing many, of the syntax of programming languages.

Rules of Form Grammar

The non-terminal symbol should appear to the left of the at least one production

The goal symbol should never be displayed to the right of the::= of any production

A rule is recursive if LHS appears in its RHS

Notational conventions symbol may be indicated by enclosing the element in square brackets. It is an arbitrary sequence of instances of the element which can be indicated by enclosing the element in braces followed by an asterisk symbol, { … }*.

It is a choice of the alternative which may use the symbol within the single rule. It may be enclosed by parenthesis ([,] ) when needed.

Two types of Notational conventions area Terminal and Non-terminals

1.Terminals:

Lower-case letters in the alphabet such as a, b, c,

Operator symbols such as +,-, *, etc.

Punctuation symbols such as parentheses, hash, comma

0, 1, …, 9 digits

Boldface strings like id or if, anything which represents a single terminal symbol

2.Nonterminals:

Upper-case letters such as A, B, C

Lower-case italic names: the expression or some

A CFG is a left-recursive grammar that has at least one production of the type. The rules in a context-free grammar are mainly recursive. A syntax analyser checks that specific program satisfies all the rules of Context-free grammar or not. If it does meet, these rules syntax analysers may create a parse tree for that programme.

Grammar derivation is a sequence of grammar rule which transforms the start symbol into the string. A derivation proves that the string belongs to the grammar’s language.

Left-most Derivation

When the sentential form of input is scanned and replaced in left to right sequence, it is known as left-most derivation. The sentential form which is derived by the left-most derivation is called the left-sentential form.

Right-most Derivation

Rightmost derivation scan and replace the input with production rules, from right to left, sequence. It’s known as right-most derivation. The sentential form which is derived from the rightmost derivation is known as right-sentential form.

Syntax Analyser Lexical Analyser

The syntax analyser mainly deals with recursive constructs of the language. The lexical analyser eases the task of the syntax analyser.

The syntax analyser works on tokens in a source program to recognize meaningful structures in the programming language. The lexical analyser recognizes the token in a source program.

It receives inputs, in the form of tokens, from lexical analysers. It is responsible for the validity of a token supplied by

the syntax analyser

It will never determine if a token is valid or not

Not helps you to determine if an operation performed on a token type is valid or not

You can’t decide that token is declared & initialized before it is being used

Syntax analysis is a second phase of the compiler design process that comes after lexical analysis

The syntactical analyser helps you to apply rules to the code

Sentence, Lexeme, Token, Keywords and reserved words, Noise words, Comments, Delimiters, Character set, Identifiers are some important terms used in the Syntax Analysis in Compiler construction

Parse checks that the input string is well-formed, and if not, reject it

Parsing techniques are divided into two different groups: Top-Down Parsing, Bottom-Up Parsing

Lexical, Syntactical, Semantical, and logical are some common errors occurs during parsing method

A grammar is a set of structural rules which describe a language

Notational conventions symbol may be indicated by enclosing the element in square brackets

A CFG is a left-recursive grammar that has at least one production of the type

Grammar derivation is a sequence of grammar rule which transforms the start symbol into the string

The syntax analyser mainly deals with recursive constructs of the language while the lexical analyser eases the task of the syntax analyser in DBMS

The drawback of Syntax analyser method is that it will never determine if a token is valid or not

You're reading Syntax Analysis: Compiler Top Down & Bottom Up Parsing Types

Learn The Syntax Of Javascript Tofixed

Introduction to JavaScript tofixed

Web development, programming languages, Software testing & others

In this article, we will study how we can maintain the uniformity in representing the decimal valued numbers representation up to specific precision according to our need using the toFixed() method of javascript. Let us first study the syntax of this method.

Below is the syntax mentioned:

It represents the number of digits you want to maintain after decimal point while displaying and manipulating the numeric object. It can be any value between 0 to 20. If not mentioned then by default it is considered as zero and the resultant numeric object will be an integral number.

It is the return value of this method which is the string representation of the passed numeric object following the fixed-point notation.

The toFixed() method may throw two exceptions which are range error and type error. Range error is caused when the number object we are using to call toFixed() method is either too large or too small. While the type error occurs when the used numeric object is not in the number format such as alphanumeric string or some symbolic values or special characters.

ToFixed() method generally returns the string representation of the passed numeric object containing the same number of digits passed as a parameter to it in the non-exponential format. The resultant value is rounded if necessary and extra zeroes are padded if necessary to return the number with specific digits. When the absolute value of the numeric object used to call toFixed() method exceeds the 1e+21, then javascript automatically calls Number.prototype.toString() method to convert the final string in exponential format.

Code:

function toFixedWorking() { let numObj = 89898.56497 let result1 = numObj.toFixed() document.getElementById(“demo1”).innerHTML = “Default working will give you an integer : “ + result1; let result2 = numObj.toFixed(2) document.getElementById(“demo2”).innerHTML = “When specified it will return number with digits after decimal as specified : ” + result2; let result3 = numObj.toFixed(6) document.getElementById(“demo3”).innerHTML = “When more than present digits are specified extra zeroes are padded at the end : ” + result3; let result4 = (0.98e+20).toFixed(2) document.getElementById(“demo4”).innerHTML = “When exponential value is mentioned and used : ” + result4; let result5 = (2.21e-10).toFixed(2) document.getElementById(“demo5”).innerHTML = “When negative exponential (very amal number is used) : ” + result5; let result6 = 98.6.toFixed(1) document.getElementById(“demo6”).innerHTML = “when literal(direct number) used instead of object : ” + result6; let result7 = 9.65.toFixed(1) document.getElementById(“demo7”).innerHTML = “When value less than present digits after decimal point is specified : ” + result7; let result8 = 9.25.toFixed(6) document.getElementById(“demo8”).innerHTML = “When value greater than present digits after decimal point is specified : ” + result8; let result9 = -98.652.toFixed(1) document.getElementById(“demo9”).innerHTML = “When negative number is used to call the method and value less than preesent digits after decimal point is specified : ” + result9; let result10 = (-5.5).toFixed(1) document.getElementById(“demo10”).innerHTML = “When negative number is used to call the method and value greater than preesent digits after decimal point is specified : ” +result10; }

The toFixed() method when used without any parameter returns the integral value that means number before the decimal point while toPrecision() method when used without specifying the parameter returns the value of the number up to which it has considerable decimal value. When we specify the parameter value less than the number of the digits present in the number the toFixed()method returns the number of the digits after decimal as specified in the parameter while the toPrecision() method returns the whole number in the digits specified in the parameter. That means the counting for the digits of the parameter starts after the decimal point in case of a toFixed() method while for the toPrecision() method starts from the first digit of the number before the decimal point. The same case happens when we have to add extra zeroes while padding when a specified parameter is greater than the digits after the decimal point.

Code:

function myFunction() { var sampleNumber = 9.54684; var defaultVal = sampleNumber.toFixed(); document.getElementById(“demo1”).innerHTML = defaultVal; var fixedVal = sampleNumber.toFixed(2); document.getElementById(“demo2”).innerHTML = fixedVal; var fixedValGreater = sampleNumber.toFixed(10); document.getElementById(“demo3”).innerHTML = fixedValGreater; var defaultVal1 = sampleNumber.toPrecision(); document.getElementById(“demo4”).innerHTML = defaultVal1; var fixedVal1 = sampleNumber.toPrecision(2); document.getElementById(“demo5”).innerHTML = fixedVal1; var fixedValGreater1 = sampleNumber.toPrecision(10); document.getElementById(“demo6”).innerHTML = fixedValGreater1; }

This is a guide to JavaScript tofixed. Here we discuss the Syntax of JavaScript tofixed and Difference between toFixed() and toPrecision() methods. You may also have a look at the following articles to learn more –

Syntax And Different Examples Of Jquery Val()

Introduction to jQuery val()

JQuery Val() is a type of method used for the operations related to the values of the elements in an HTML based web page. The two operations where this method can be used are to set the value for a given element or to get the value for a given element. One can also used an already defined and declared function to fetch the element property, for which the val() method can be used to set or get the values. The syntax for this method is ‘$(selector).val()’, where val will have the value as a parameter and sometimes the function details wherever applicable.

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Web development, programming languages, Software testing & others

Syntax:

This method is used to set the value of a selected element.

This method is used to set the value of a selected element by using a function.

Parameters:

Value: The value parameter is not an optional parameter, which is used to specify the set value of the attribute.

function ( index, currvalue ): Function ( index, currvalue ) parameter is an optional parameter, which is used to specify the name of a function to execute and return the set value of the attribute.

Below given are the examples of jQuery val():

Next, we write the html code to understand the jQuery val ( ) method more clearly with the following example where we set the value attribute of the second and third input element with the value content of the first input element –

Code:

$(document).ready(function() { var cont = $(“input”).val(); $(“input”).val( cont ); });

Output:

Next example code where this method is used to get the form’s elements values. The jQuery val( ) method doesn’t accept any arguments and returns an array containing the value of each selected options in a list else returns a NULL value if no option is selected, as in the below code –

Code:

b { color: red; } p { background-color: yellow; margin: 10px; } function fruitdisplayVals() { var fruitValues = $( “#fruit” ).val(); } $( “select” ).change( fruitdisplayVals ); fruitdisplayVals();

Output:

In the next example code, we rewrite the above code for jQuery val() method with single and multiple select boxes –

Code:

b { color: red; } p { background-color: yellow; margin: 4px; } function fruitdisplayVals() { var fruitValues = $( “#fruit” ).val(); } $( “select” ).change( fruitdisplayVals ); fruitdisplayVals();

Output:

Now we can select any single fruit option and multiple vegetable options, the output is –

Next example code where the jQuery wrap( ) method accepts a string to set the value of each matched element. As shown in the below example –

Code:

$(document).ready(function(){ $(“input:text”).val(“Set Value”); }); });

Output:

This method accepts a function as a parameter and sets the value of each matched element.

Code:

$(document).ready(function(){ $(“input:text”).val( function(n,c){ return c+”Set Value”; }); }); });

Output:

This method is used to get the value of the html element or to set the value of the html element. Syntax for this are –

$(selector).val( )

$(selector).val( value )

$(selector).val( function ( index, currvalue ) )

Value used to specify the set value of the attribute. function ( index, currvalue ) used to specify the name of a function to execute and return the set value of the attribute.

This has been a guide to jQuery val(). Here we discuss the syntax, parameters, and various examples of jQuery val(). You may also have a look at the following articles to learn more –

What Is Statistical Data Analysis?

Statistical data analysis does more work for your business intelligence (BI) than most other types of data analysis.

Also known as descriptive analysis, statistical data analysis is a wide range of quantitative research practices in which you collect and analyze categorical data to find meaningful patterns and trends.

Statistical data analysis is often applied to survey responses and observational data, but it can be applied to many other business metrics as well.

See below to learn more about statistical data analysis and the tools that help you to get the most out of your data:

See more: What is Data Analysis?

Before you get started with statistical data analysis, you need two pieces in place: 1) a collection of raw data that you want to statistically analyze and 2) a predetermined method of analysis.

Depending on the data you’re working with, the results you want, and how it is being presented, you may want to choose either of these two types of analysis:

Descriptive statistics: datadoesn’t mean much on its own, and the sheer quantity can be overwhelming to digest. Descriptive statistical analysis focuses on creating a basic visual description of the data, or turning information into graphs, charts, and other visuals that help people understand the meaning of the values in the data set. Descriptive analysis isn’t about explaining or drawing conclusions, though. It is only the practice of digesting and summarizing raw data, so it can be better understood.

This type of statistical analysis is all about visuals. Rawdatadoesn’t mean much on its own, and the sheer quantity can be overwhelming to digest. Descriptive statistical analysis focuses on creating a basic visual description of the data, or turning information into graphs, charts, and other visuals that help people understand the meaning of the values in the data set. Descriptive analysis isn’t about explaining or drawing conclusions, though. It is only the practice of digesting and summarizing raw data, so it can be better understood.

Statistical inference:

Inferential statistics practices involve more upfront hypothesis and follow-up explanation than descriptive statistics. In this type of statistical analysis, you are less focused on the entire collection of raw data and instead take a sample and test your hypothesis or first estimation. From this sample and the results of your experiment, you can use inferential statistics to infer conclusions about the rest of the data set.

Every company has several key performance indicators (KPIs) to judge overall performance, and statistical data analysis is the primary strategy for finding those accurate metrics. For internal, or team metrics, you’ll want to measure data like associated deals and revenue, hours worked, trainings completed, and other meaningful numerical values. It’s easy to collect this data, but to make meaning of it, you’ll want to statistically analyze the data to assess the performance of individuals, teams, and the company. Statistically analyzing your team is important, not only because it helps you to hold them accountable, but also because it ensures their performance is measured by unbiased numerical standards rather than opinions.

If your organization sells products or services, you should use statistical analysis often to check in on sales performance as well as to predict future outcomes and areas of weakness. Here are a few areas of statistical data analysis that keep your business practices sharp:

Competitive analysis:

Statistical analysis illuminates your objective value as a company. More importantly, knowing common metrics like sales revenue and net profit margin allows you to compare your performance to competitors.

True sales visibility:

Your salespeople say they are having a good week and their numbers look

good, but how can you accurately measure their impact on sales numbers? With statistical data analysis, you can easily measure sales data and associate it with specific timeframes, products, and individual salespeople, which gives you better visibility on your marketing and sales successes.

Predictive analytics:

One of the most crucial applications of statistical data analysis, predictive analytics allow you to use past numerical data to predict future outcomes and areas where your team should make adjustments to improve performance.

See more: What is Raw Data?

In virtually any situation where you see raw quantitative and qualitative data in combination, you can apply statistical analysis to learn more about the data set’s value and predictive outcomes. Statistical analysis can be performed manually or through basic formulas in your database, but most companies work with statistical data analysis software to get the most out of their information.

A couple of customers of top statistical data analysis software have also highlighted other uses they found in the software’s modules:

“[TIBCO Spotfire is a] very versatile and user friendly software that allows you to deploy results quickly, on the fly even. Data transparency and business efficiency is improved tremendously, without the need for an extensive training program or course. On the job is the best way to learn using it, figuring problems out with the aid of the community page and stackoverflow, and if all else fails there are committed consultancies that can sit with you and work out complex business needs, from which you will gain another level of understanding of the software onto which you can build further. We use this software not only for data analytics, but also for data browsing and data management, creating whole data portals for all disciplines in the business.”

-data scientist in the energy industry, review from

Gartner Peer Insights

“Although not a new tool, [IBM] SPSS is the best (or sometimes the only) tool to effectively analyze market research surveys

—

response level data. our team has explored many other solutions but nothing comes close…We conduct many consumer surveys. we need to analyze individual respondents, along with their individual responses or answers to each question

—

which creates an unlimited number of scenarios. SPSS is flexible enough for us to get answers to questions we may not have predicted at the beginning of a project.”

-senior manager of consumer insights and analytics in the retail industry, review from

Gartner Peer Insights

See more: Qualitative vs. Quantitative Data

The market for statistical analysis software hit $51.52 billion in 2023 and is expected to grow to $60.41 billion by 2027, growing at a steady annual rate of 2.3% between 2023 and 2027, according to Precision Reports. Statistical analysis software is used across industries like education, health care, retail, pharmaceuticals, finance, and others that work with a large amount of quantitative data. Companies of all sizes implement this kind of software, but most of the latest implementations come from individuals and small-to-medium enterprises (SMEs), Precision Reports says.

Are you curious about the different statistical data analysis tools on the market? Looking for a new solution to replace your current approach? Check out these top statistical data analysis tools or use this Data Analysis Platform Selection Tool from TechnologyAdvice to guide your search.

AcaStat

IBM SPSS

IHS Markit EViews

MathWorks MATLAB

MaxStat

Minitab

SAP

SAS Institute

StataCorp Stata

TIBCO Spotfire

Cloud Security Market Forecast & Analysis

The 2023 SolarWinds cyber attack is widely considered one of the worst security incidents in recent years and — after the smoke clears (investigations are still ongoing) — will likely take the prize for the biggest cloud security failure in history.

With Microsoft, Cisco, Intel, NATO, the U.K. government, the U.S. government, the European Parliament, and thousands of other high-profile customers falling victim to the attackers, the incident illustrates how security failures in today’s integrated cloud environments can have such a devastating and widespread impact, catching even the most well-protected organizations off guard.

Cloud security failures on several levels ultimately led to the successful supply chain attack. Initially, cyber criminals were able to infiltrate SolarWinds’ internal systems by first compromising its Microsoft 365 email services and Azure cloud infrastructures. This ultimately led to attackers being able to move laterally through the cloud, accomplishing their mission to hide malware in SolarWinds software updates to customers.

Amazon Web Services (AWS) also came under fire for enabling the cyber criminals to utilize its infrastructure-as-a-service (IaaS) resources to carry out the attack. This reveals an interesting facet of cloud security that makes it unique from other cyber disciplines: with instantly provisioned and scalable IT resources, effective cloud security becomes not just a matter of protecting the business from being attacked — it’s also about not being used unwittingly to attack others.

With the rise of software-defined networks (SDN), DevOps, and cloud automation platforms, the line between application and infrastructure security has been gradually blurring.

For this reason, cloud security is a unique discipline, as traditional security approaches fail to keep up with rapidly evolving agile environments and DevSecOps processes. Developers working in cloud-based environments frequently use containerization software, like Docker, for application portability as well as Kubernetes to orchestrate (e.g., spin up/down en masse) and cluster those containerized applications.

These environments specifically require cloud security solutions versus traditional security platforms designed to protect on-premises IT networks and assets.

Additionally, with many enterprises using a mix of public cloud-based infrastructure/apps and private cloud or on-premises IT assets, hybrid cloud security is also a rapidly growing space.

The global cloud security market is worth $34.8 billion in 2023 and is expected to hit $67.6 billion by 2026, increasing during that period at a compound annual growth rate (CAGR) of 14.2%, according to chúng tôi

The shift of the global workforce to the home office — and subsequently the public cloud — has resulted in a spike in cyber crime as malicious opportunists seek to prey on less-experienced internet and email users as well as enterprises as their IT and security staff are busy transitioning to a global remote workforce.

In the past, cloud security solutions were primarily designed to address the needs of cloud-native applications and/or virtual infrastructures.

Newer cloud-based offerings provide unified security management and orchestration for both on-premises networks and cloud infrastructures.

Not only does this streamline administration and allow for cloud-based management of on-premises IT resources, it also enables organizations to leverage the metered resources to quickly scale up protective measures against active cyber attacks or malware campaigns.

See more: Key Cybersecurity Trends 2023

Public cloud providers such as AWS, Google Cloud, and Microsoft Azure enable developers to quickly spin up the virtual infrastructure resources needed to build their applications on top of the cloud.

This makes modern software development arguably the most prominent use case in the cloud security space. Indeed, several vendors market products on the cloud application side of affairs — most notably cloud access security broker (CASB), container security, and zero-trust access solutions.

Secure access service edge (SASE) in particular has seen a dramatic increase in adoption during the global pandemic, mainly due to the massive shift toward working from home.

With employees using unmanaged devices to access corporate IT environments in droves, the limitations of legacy virtual private network (VPN) and traditional remote access quickly manifest themselves in poor application performance, availability issues, and the emergence of security gaps.

Use cases abound for general enterprises looking to leverage the cloud for providing remote workers a more secure, rapid response to corporate network resource demands.

The following are 10 leading cloud security vendors, from cloud security monitoring services to security for hybrid cloud environments:

Halo, Cloud Passage’s flagship platform, improves the security of private/public/hybrid cloud deployments by automating cloud security and compliance controls.

Forcepoint develops secure access service edge (SASE) solutions, among others, as well as a cloud access security broker (CASB) solution: a cloud/on-premise hardware or software device that sits between users and cloud service providers to monitor for security issues.

Now a part of VMware, Carbon Black offers a cloud-native platform for endpoint protection. The solution features a wide array of features, from threat hunting to its next-generation antivirus (NGAV)—AI-powered malware detection/prevention..

Acqua focuses on security monitoring for cloud environments—virtual and serverless infrastructure, microservices, containers, and more.

The recent acquisitions of Twistlock and Puresec position Palo Alto Networks solidly in the container and serverless security space. Leading cloud-native app developers have already found these two vendors’ offerings indispensable; now, they’ve joined the cybersecurity giant’s lineup of leading solutions, from the cloud to the edge.

Qualys offers a platform for cloud security that includes cloud agents, scanners, sensors, SaaS connectors, and more for comprehensive visibility and insights regarding potential security gaps and vulnerabilities.

Zscaler is focused on developing cloud-native security solutions such as its Zscaler Internet Access—a security stack as-a-service delivered completely via the cloud, and Zscaler’s Private Access (ZPA), a cloud service that enforces zero-trust access for private applications in the public cloud or on-premise data center.

A leader in identity security, CyberArk is known for its Privileged Access Manager, designed specifically for mitigating account exploitation risk in AWS public cloud/hybrid environments.

Incidents like the SolarWinds data breach illustrate how integral cloud security is to the software ecosystems of today.

In an age of software as-a-service (SaaS), integrations, and APIs, enterprises must adopt a layered cloud security strategy leveraging some (or most) of vendor technologies.

Cloud security solutions must also be multi-faceted and capable on several levels: to protect the growing number of hybrid cloud deployments as well leverage AI/ML to counter increasingly sophisticated cyber attackers.

Basics Linux/Unix Commands With Examples & Syntax (List)

File Management becomes easy if you know the right basic command in Linux.

Sometimes, commands are also referred as “programs” since whenever you run a command, it’s the corresponding program code, written for the command, which is being executed.

Let’s learn the must know Linux basic commands with examples:

If you want to see the list of files on your UNIX or Linux system, use the ‘ls’ command.

It shows the files /directories in your current directory.

Note:

Directories are denoted in blue color.

Files are denoted in white.

You will find similar color schemes in different flavors of Linux.

Suppose, your “Music” folder has following sub-directories and files.

You can use ‘ls -R’ to shows all the files not only in directories but also subdirectories

NOTE: These Linux basics commands are case-sensitive. If you enter, “ls – r” you will get an error.

‘ls -al’ gives detailed information of the files. The command provides information in a columnar format. The columns contain the following information:

1st Column

File type and access permissions

2nd Column

# of HardLinks to the File

3rd Column

Owner and the creator of the file

4th Column

Group of the owner

5th Column

File size in Bytes

6th Column

Date and Time

7th Column

Directory or File name

Let’s see an example –

Hidden items in UNIX/Linux begin with –

at the start, of the file or directory.

Any Directory/file starting with a ‘.’ will not be seen unless you request for it. To view hidden files, use the command.

The ‘cat’ server command is used to display text files. It can also be used for copying, combining and creating new text files. Let’s see how it works.

To create a new file, use the command

Add content

Press ‘ctrl + d’ to return to command prompt.

How to create and view files in Linux/Unix

To view a file, use the command –

Let’s see the file we just created –

Let’s see another file sample2

The syntax to combine 2 files is –

Let’s combine sample 1 and sample 2.

As soon as you insert this command and hit enter, the files are concatenated, but you do not see a result. This is because Bash Shell (Terminal) is silent type. Shell Commands will never give you a confirmation message like “OK” or “Command Successfully Executed”. It will only show a message when something goes wrong or when an error has occurred.

To view the new combo file “sample” use the command

Note: Only text files can be displayed and combined using this command.

The ‘rm’ command removes files from the system without confirmation.

To remove a file use syntax –

How to delete files using Linux/Unix Commands

To move a file, use the command.

Suppose we want to move the file “sample2” to location /home/guru99/Documents. Executing the command

mv sample2 /home/guru99/Documents

mv command needs super user permission. Currently, we are executing the command as a standard user. Hence we get the above error. To overcome the error use command.

Sudo program allows regular users to run programs with the security privileges of the superuser or root.

Sudo command will ask for password authentication. Though, you do not need to know the root password. You can supply your own password. After authentication, the system will invoke the requested command.

Sudo maintains a log of each command run. System administrators can trackback the person responsible for undesirable changes in the system.

For renaming file:

NOTE: By default, the password you entered for sudo is retained for 15 minutes per terminal. This eliminates the need of entering the password time and again.

You only need root/sudo privileges, only if the command involves files or directories not owned by the user or group running the commands

Directory Manipulation in Linux/Unix

Enough with File manipulations! Let’s learn some directory manipulation Linux commands with examples and syntax.

Creating Directories

Directories can be created on a Linux operating system using the following command

This command will create a subdirectory in your present working directory, which is usually your “Home Directory”.

For example,

If you want to create a directory in a different location other than ‘Home directory’, you could use the following command –

For example:

will create a directory ‘Music’ under ‘/tmp’ directory

You can also create more than one directory at a time.

To remove a directory, use the command –

Example

will delete the directory mydirectory

Tip: Ensure that there is no file / sub-directory under the directory that you want to delete. Delete the files/sub-directory first before deleting the parent directory.

The ‘mv’ (move) command (covered earlier) can also be used for renaming directories. Use the below-given format:

Let us try it:

How to rename a directory using Linux/Unix Commands

Man stands for manual which is a reference book of a Linux operating system. It is similar to HELP file found in popular software.

To get help on any command that you do not understand, you can type

The terminal would open the manual page for that command.

For an example, if we type man man and hit enter; terminal would give us information on man command

History command shows all the basic commands in Linux that you have used in the past for the current terminal session. This can help you refer to the old commands you have entered and re-used them in your operations again.

This command clears all the clutter on the terminal and gives you a clean window to work on, just like when you launch the terminal.

Many times you would have to type in long commands on the Terminal. Well, it can be annoying at times, and if you want to avoid such a situation then copy, pasting the commands can come to rescue.

How to print a file using Linux/Unix commands

Let’s try out some Linux basic commands with examples that can print files in a format you want. What more, your original file does not get affected at all by the formatting that you do. Let us learn about these commands and their use.

‘pr’ command

This command helps in formatting the file for printing on the terminal. There are many Linux terminal commands available with this command which help in making desired format changes on file. The most used ‘pr’ Unix commands with examples are listed below.

Option Function

-x

Divides the data into ‘x’ columns

-h “header”

Assigns “header” value as the report header

-t

Does not print the header and top/bottom margins

-d

Double spaces the output file

-n

Denotes all line with numbers

-l page length

Defines the lines (page length) in a page. Default is 56

-o margin

Formats the page by the margin number

Let us try some of the options and study their effects.

‘Tools’ is a file (shown below).

We want its content to be arranged in three columns. The syntax for the same would be:

The ‘-x’ option with the ‘pr’ command divides the data into x columns.

The syntax is:

The ‘-h’ options assigns “header” value as the report header.

As shown above, we have arranged the file in 3 columns and assigned a header

The syntax is:

This command denotes all the lines in the file with numbers.

These are some of the ‘pr’ command options that you can use to modify the file format.

Once you are done with the formatting, and it is time for you to get a hard copy of the file, you need to use the following command:

In case you want to print multiple copies of the file, you can use the number modifier.

In case you have multiple printers configured, you can specify a particular printer using the Printer modifier

In windows, the installation of a program is done by running the chúng tôi file. The installation bundle contains the program as well various dependent components required to run the program correctly.

Using Linux/Unix basic commands, installation files in Linux are distributed as packages. But the package contains only the program itself. Any dependent components will have to be installed separately which are usually available as packages themselves.

You can use the apt commands to install or remove a package. Let’s update all the installed packages in our system using command –

The easy and popular way to install programs on Ubuntu is by using the Software center as most of the software packages are available on it and it is far more secure than the files downloaded from the internet.

Also Check:- Linux Command Cheat Sheet

For sending mails through a terminal, you will need to install packages ‘mailutils’.

The command syntax is –

Once done, you can then use the following syntax for sending an email.

This will look like:

Press Cntrl+D you are finished writing the mail. The mail will be sent to the mentioned address.

Summary:

You can format and print a file directly from the terminal. The formatting you do on the files does not affect the file contents

In Unix/Linux, software is installed in the form of packages. A package contains the program itself. Any dependent component needs to be downloaded separately.

You can also send e-mails from terminal using the ‘mail’ network commands. It is very useful Linux command.

Below is a Cheat Sheet of Linux/ Unix basic commands with examples that we have learned in this Linux commands tutorial

Command Description

ls Lists all files and directories in the present working directory

ls – R

Lists files in sub-directories as well

ls – a

Lists hidden files as well

ls – al

Lists files and directories with detailed information like permissions, size, owner, etc.

Creates a new file

cat filename

Displays the file content

Joins two files (file1, file2) and stores the output in a new file (file3)

mv file “new file path”

Moves the files to the new location

mv filename new_file_name

Renames the file to a new filename

sudo

Allows regular users to run programs with the security privileges of the superuser or root

rm filename

Deletes a file

man

Gives help information on a command

history

Gives a list of all past basic Linux commands list typed in the current terminal session

clear

Clears the terminal

mkdir directoryname

Creates a new directory in the present working directory or a at the specified path

rmdir

Deletes a directory

Renames a directory

pr -x

Divides the file into x columns

pr -h

Assigns a header to the file

pr -n

Denotes the file with Line Numbers

lpr c

Prints “c” copies of the File

lp -d

lpr -P

Specifies name of the printer

apt-get

Command used to install and update packages

mail -s ‘subject’ -c ‘cc-address’ -b ‘bcc-address’ ‘to-address’

Command to send email

mail -s “Subject” to-address < Filename

Command to send email with attachment

Download Linux Tutorial PDF

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