What is bash terminal?

When a computer starts up, a kernel (whether Linux, BSD, Mach, or NT) detects all of the physical hardware and allows each component to communicate with one another and be managed by some basic software.

The most basic set of instructions in a computer just maintains it switched on and safe, such as occasionally activating fans to avoid overheating, using subsystems to monitor disk space or "listen" for newly added devices, and so on. Computers would be about as intriguing as a convection oven if this was all they did.

It was a significant advancement at a period when humans relied on punchcards to tell computers what to perform.

Bash is an application

We're prompted with a prompt when we start a terminal (such as the GNOME Terminal or Konsole on Linux or iTerm2 on macOS) running the Bash shell. A prompt is a symbol that indicates that the shell is waiting for our input. It is commonly a dollar sign ($). Knowing what we're supposed to type, on the other hand, is a another story.

This may come off as nasty, but it's a perfect summation of the various connotations associated with the name "Bash." For many new users, there's no distinction between Bash and Linux or Unix: it's the traditional black-screen-with-green-text where we're expected to write what our computer should do next.

The Bash shell and the commands we write into it are so conflated. It's critical to recognize the distinction between the two: Bash is merely a program whose primary function is to execute other programs (in the form of commands) that are installed on the same system.

We can learn Bash, but only as part of a larger understanding of the operating system on which it runs. We can't accomplish anything with Bash unless we know the commands.

Many digital historians utilize one of two command-line interfaces, also known as "shells." The shell is known as bash, or the 'Bourne-again shell,' on OS X and many Linux installations. The command-line interface on Windows-based systems is by default MS-DOS-based, which employs distinct commands and syntax but can often do identical tasks.

We can traverse through our file system using the terminal to identify files, open them, conduct basic data manipulation activities like merging and copying files, as well as read and make very minor adjustments.

Linux commands

When we give Bash a command, it looks in certain directories on our system to determine if it already exists. Bash will definitely run the command if it is present in the directories.

Bash is a command that is normally executed by default when we open a terminal window or log into a text console. We can use the which command in a terminal to find out where any command, including Bash, is located on our system:

Bash comes with a few built-in commands. The majority of built-in commands are tailored to Bash scripting or low-level environment settings, but a few, such as cd, are widely helpful (for change directory). Because they aren't in our typical executable path, built-in commands don't show up when we search for them:

They're still available, however, because they're part of Bash, and we're using Bash.

Running Bash

By default, most recent Linux and Unix distributions include a Bash shell. As we know the Bash is well-known and it also has a number of useful features that other shells lack so it is included in these distributions by default. Some systems, on the other hand, utilize a different shell by default.

We may use the echo command with a specific variable reflecting the name of the currently running process to see if we're running a Bash shell:

If there is no bash on your system then you can try installing it from the google. It is very simple to install in any distribution or one can visit the Bash official website.

Working in Bash

Bash is a valid computer interface that isn't just for server administrators and programmers. It might be our computer's desktop, word processor, graphics editor, and so much more. Some users prefer Bash to desktop applications.

There is no limit of command that are already available for the use of Unix and Linux which may surprise the individual. We can resize and crop photos without ever opening them in a viewer or editor, for example:

We can use ogg123 or mpg321 to play music, sox to convert audio, ffmpeg to alter and edit video, emacs or vim to edit text, pine or mutt to check email, elinks to browse the internet, ranger or midnightcommander to browse files, and so much more. Everything is done in Bash, with commands available on our machine or in our software repository.

Bash scripting

One of the reasons Bash (and Linux in general) is so strong is that it can be scripted. We can list everything we can write into Bash in a plain-text file and have Bash run it for us. Rather than spending an afternoon manually running a hundred commands, we may script them and have our computer run them while we focus on other tasks.

Because almost everything on Linux runs on top of the Bash shell, Bash can be used to automate almost everything. While there are exceptions (graphical apps may have their own scripting language or no scripting at all), scripting our operating system allows us to perform tens of thousands of functions on our computer without having to do them ourself.

It's impossible to determine how much time this saves Linux users each day. But it's not the standard automation that makes the difference; it's the custom processes that people create for themselves, the tasks that no one else considers to be automated.

For example, consider the following Bash script, which changes a temporary file (imagine a file produced by a different process) to a certain directory:

That's correct, Bash. In order to validate the last command , copy and paste it in the terminal. The command works as long as there is a file named tmp.png and a directory named /public html.

Learning Bash, on the other hand, is all about figuring out how to improve a simple command like this for the purposes of automation. If the file tmp.png does not exist, for example, the script will fail.

If this script is a critical component of, say, a blogging site that needs a fresh image every day to create a bespoke header image, then its failure could result in catastrophic failures elsewhere. In order to enhance resiliency a user who knows Bash can use the following command.

This is just one example of the process of learning to script with Bash, but it shows how understanding Linux and Bash are complementary rather than mutually exclusive.

Advantages of Bash

Bash users adore these "Bashisms" because they bypass the sometimes lengthy and cumbersome syntax of other shells such as tcsh and ash.

They are, however, Bash-specific and non-POSIX compliant, which may cause compatibility issues on systems that do not run Bash. However, because Bash is open source and free software, most people will be able to install it if they require it. The absence of compatibility imposes an additional dependence, but it does not prevent anyone from utilizing a script.

The main advantages that can be pointed out are -

• Creating a shell script is becoming increasingly faster.
• Easy to get started
• There's an option for interactive debugging.

Disadvantages

Everything that has an advantage it also has some of the missing points, they are -

• Extra caution is essential to avoid potentially dangerous situations.
• The execution speed is usually slow.
• There are numerous problems in the design and implementation.
• In comparison to other programming languages like Python, it provides fairly limited data structure capabilities.