What is backslash in linux

BackSlash Linux will no longer receive updates.

Before I get into any more details and reasoning, I apologise for discontinuing the project so abruptly. I know quite a few people liked this distribution, but I have reasons for discontinuing the project. And therefore, I announce that the project will be in a ‘fully discontinued’ state as of September 15, 2021, and no new versions will be released. Any new patches to the existing systems won’t be released, and there won’t be any updates of any type — In fact, there has been none for some time.

Nostalgia.

The first version of BackSlash Linux – Anna was initially released in November 2016, and this was a project that I had been working on for a long time. I was then a student of Computer Science, and I was just too much excited to build something. The earlier versions were no different than the Cinnamon and the Pantheon default desktops. It was the third version – Olaf, in which the BackSlash Shell brought some serious look and feel changes, and the community was also optimistic about it, for the most part. As BackSlash Linux evolved, the last release, Kristoff, was one of the most beautiful looking Linux distributions out there for a while. BackSlash has enjoyed its days for sure, and now is the time to say goodbye.

The current state of Linux — the factor impacting the decision.

As a lot of you might know that BackSlash Linux used to run on the Linux kernel, just like all other Linux based operating systems, and that is the main reason for discontinuing this project. The big «obsolete» monolithic kernel is one of the major facts. Microkernels are all the rage right now because of speed and security. This is the reason Google is replacing Android with Fuschia. This is why Huawei is developing its Operating System for phones called Harmony/Hongmeng on a microkernel architecture. Linux, on the other hand, is a monolithic kernel. It suffers from the same problem every monolithic suffers from – the risk of the entire system crashing due to a bug in a device driver, the reason being it is running in the same area with the kernel and other drivers, so, if something fails every other driver and program will be affected.

So are microkernels the way? Well, the answer is somewhat tricky. As I said earlier, a microkernel system is «theoretically» more stable since a failure in one part of the system won’t bring the whole thing down. But failures usually occur because of poorly written code or someone not following best practices in their programming. Microkernels tend to be hard to debug too. So, as incredible as they might sound, in practice, they perform horribly (mostly due to programming errors).

This rarely happens in Linux unless you’re intentionally running pre-release or untested software. You don’t get bad kernel-level code in Linux because Linus won’t stand for it. Part of the reason why the Linux kernel has been so successful is because Linus Torvalds is a dictator when it comes to its development. If you do things right from the start, it doesn’t matter what type of kernel you’re running. Linux and its «obsolete» monolithic kernel are so stable that 85 per cent of the servers in the world use it. Doing things the right way is always more important than being dogmatic about methods or design choices. Linus uses his horse-and-buggy C programming language and his monolithic kernel, and they just work.

Wait, if monolithic kernels also work, then why is the project being discontinued? The fact that the Linux kernel gets somewhere in the neighbourhood of 2+ million lines of code merged every year, and all the rest have also to be maintained. There will come a time when the project becomes too hard to maintain and considered unmaintainable. At that point, almost every future release of every Linux based operating system will break and will have to migrate to an alternative choice. BackSlash Linux is just one of the first to do so.

The return to the roots.

As I just mentioned, BackSlash Linux is one of the first distributions to migrate from the Linux kernel — this might make you think that BackSlash Linux will continue to be developed, but with some other kernel! And the answer to that is Yes and also No — which together makes Yo! Okay, bad joke! I am working on a new project with a team where we will create an entirely new operating system that will be much more stable and secure while being beginner-friendly and modern looking. The new project will be based on the forefather of all projects — the mighty UNIX. We would be utilising the BSD kernel for this. We will probably make it hybrid instead of monolithic — as most new operating systems like macOS, Windows, iOS and DragonFly BSD have done. The project is in the ideation phase right now, and I will update this website and all social media platforms once we have a working product ready. Like all great things — this would also take some time to be done.

What this means for you — the end user.

Well, there are no new updates for you, unfortunately. This website will continue to function as usual, and you will be able to download the older releases of BackSlash Linux. But I probably, won’t advise using BackSlash Linux as your primary system too. No support options would be available — support has been too limited for some time too. Social media handles of BackSlash Linux would be kept intact, and you are free to show some love by tagging BackSlash Linux in a post and/or posting on the timeline of the project page.

Where to go from here.

As I said, there’s a transition happening now, and most operating systems have already switched to Hybrid kernels. Linux is the only one lagging and will probably remain so for a long time. I’m not going to try and read the tea leaves and figure out what the future looks like in that regard. The question for BackSlash Linux is, «Do we try to survive through that transition?» A few months ago, I thought the answer was obvious and that we would, but now I’m convinced of the opposite.

If you’re ever looking for a great alternative and you wish to use a Linux distribution made in India, Garuda Linux is one of the best choices right now — which I can recommend. The system is also optimised for gaming and also looks pretty.

I am putting up a Wall, where you can post your thoughts and memories about BackSlash Linux. I hope I will see you guys soon.

— Kumar Priyansh
Former Developer and Maintainer
BackSlash Linux

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What does dot backslash mean in Linux?

A short breakdown

Before we get into what dot backslash means in Linux, let us define some discussion points. All of these are crucial to understanding the dot slash feature, and we have taken it upon ourselves to walk you through all of it.

So, without any further ado, let’s get into it.

What is PATH?

In Linux and other Unix-like systems, we use the command-line to run executable programs through commands. However, the shell does need to be pointed in the right direction by something to address our demands of running executables. That’s where the environmental variable PATH comes in.

PATH is an environmental variable responsible for telling the shell where to look for the programs (executable files) we want to run. This variable holds great significance in the operating system since it effectively increases the convenience and safety of the system.

Environmental variables are just a particular class of variables that hold modifiable values. Keep in mind that there is a subtle but important difference between the uppercase PATH and the lowercase path. The second one is simply the address of a directory or file in the system.

You can check the PATH variable by running the following command in the Terminal.

Now that we have covered some ground about the environmental variable PATH, we learn about the root directory to use these concepts in conjunction with our main topic.

What is the root directory?

This section will expand on the root directory without getting totally lost in the details of the Filesystem Hierarchy Standard (FHS) of Linux. It is closely related to the PATH variable we previously mentioned; therefore, a small discussion is needed.

The root directory sits comfortably at the very top of the Linux filesystem hierarchy. It contains every file and directory on your computer, including the libraries, boot files, binaries, user files, configuration settings, temporary files, and much more.

In short, the root directory serves as the general reference point for addressing files and directories in your computer.

Difference between absolute and relative path

Next on our list is the absolute and relative path. We will be using the concepts mentioned above of root and path to determine the difference between the two.

An absolute path is a file or directory location concerning the root directory, not the current directory. Therefore, the complete address of a file in the computer is referenced by the root directory. The absolute path contains all the necessary information about the file or directory it is describing.

On the other hand, a relative path is used to describe a file/directory location concerning the current directory. It does not trace the address of a file from the root directory, rather from where you have set the current directory.

What does dot mean in Linux?

Dot, or “.” addresses the current user directory. Through this feature or operator, you can find where the current directory is set. Let’s see how we can achieve that as well.

Open a new Terminal window through the Activities menu or hit Ctrl + Alt + T on your keyboard. The next step is to execute the command given below.

You can see that in the output, the current user directory is highlighted by the line ending with a dot.

With that being said, we are halfway through understanding the purpose of dot backslash in Linux. Let us move on to the next section to discuss two types of slash operators (forward and back).

What does slash mean in Linux?

As mentioned earlier, there are two types of slashes, both with completely different purposes. Therefore, we must draw a clear distinction between the two.

The forward slash, /, when appended to the end of a dot, makes sure that you are not operating on a file. The same happens when adding a slash to the end of the name of a directory. Let’s take a look at how you can use it with a dot.

First, we check our home directory by the following command.

We are going to place a sample text file in the folder /home/sample/. We can use dot slash to do this without changing the current directory.

Note that our sample text file was accessed and modified without us having to change the current directory. Next, we can check the changes we made through the cat command.

And now, we get the output as:

To conclude the story of “./”, we can say that it allows us to address the current directory. So, we can also use it on our PATH variable to access files that are not in our current directory without ever leaving the current directory.

Next, we have the backslash, \. In Unix systems, and even some programming languages like C, the role of the backslash is to indicate to the system that the next character has a special meaning. Therefore, it works as an escape character. For example, a lowercase n, when used with a backslash, \n, indicates a new line character. Many other characters can be used instead of n to achieve different tasks. Let’s implement this in our Terminal. Here, %s is the string placeholder, \n is the newline character, and the rest of the three lines are the strings inputted to the placeholders.

Thus, now we have demonstrated the purpose of both of the slashes.

Conclusion

In this article, we went into great detail about the dot backslash feature in Linux. We learned the basic concepts of PATH, relative and absolute paths, the root directory, dots, slashes, and finally, how they are implemented in conjunction with each other.

About the author

Zeeman Memon

Hi there! I’m a Software Engineer by degree, Blogger by skills who loves to write about tech, develop websites & do SEO. You can reach out to me on LinkedIn.

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What does backslash dot mean as a command?

A software I installed inserted a line in my profile that reads:

I know dot . is synonymous with source , so I suspect this is just sourcing the file, but I have never seen \. before; does it do something else?

Edit, regarding DVs: searching for «backslash dot» leads to questions regarding ./ when calling executable files, and man source leads to a manpage where \. does not appear. I don’t know what else to try, hence the question.

Edit 2: see related questions

2 Answers 2

A backslash outside of quotes means “interpret the next character literally during parsing”. Since . is an ordinary character for the parser, \. is parsed in the same way as . , and invokes the builtin . (of which source is a synonym in bash).

There is one case where it could make a difference in this context. If a user has defined an alias called . earlier in .profile , and .profile is being read in a shell that expands aliases (which bash only does by default when it’s invoked interactively), then . would trigger the alias, but \. would still trigger the builtin, because the shell doesn’t try alias expansion on words that were quoted in any way.

I suspect that . was changed to \. because a user complained after they’d made an alias for . .

Note that \. would invoke a function called . . Presumably users who write functions are more knowledgeable than users who write aliases and would know that redefining a standard command in .profile is a bad idea if you’re going to include code from third parties. But if you wanted to bypass both aliases and functions, you could write command . . The author of this snippet didn’t do this either because they cared about antique shells that didn’t have the command builtin, or more likely because they weren’t aware of it.

By the way, defining any alias in .profile is a bad idea because .profile is a session initialization script, not a shell initialization script. Aliases for bash belong in .bashrc .

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