aayush pal

Why Read?

2024-02-10T00:00:00Z

My original idea was to share my opinions on why everyone should write. But then I don’t have many blogs of mine to showcase and it would be impractical to preach what I don’t practise. So I turned towards what I do a lot of i.e. I read a lot. Reading is very natural to humans. We share & perceive information in text. But this is definitely not so natural for everyone, just like going to the gym regularly is not natural for everyone either. But I was an avid book reader back in the school, picking up whatever titles would be available back then in a pretty common convent school. Reading as many as I could in an academic year, hoping to go big the next one was my chime.

I don’t read as many books today. But I still do a lot of reading everyday. Mostly in the form of articles, writings, blogs, by people I follow or come across on social media. These could be all about things like life, engineering to travel, health, finance, etc.

What does reading give you? Reading builds a perspective. Reading allows you to understand society’s opinions on topics of matter. Reading can be a calming activity for our ever-active brains. It truly feels therapeutic to be completely drawn in on a white page with some text on it, that somehow seems to build a bridge between you and the writer. With above point in context, reading makes you relate to the writer - who could be someone more experienced in a specific art, skill and that allows you to be inspired and create something of your own. (Which is why this article exists).

Conclusion

Reading is what eventually brought me to writing this article. I have come across so many interesting engineers who write to express their views and share their experiences. I would like to achieve a similar glimpse through my writing and become part of the community that loves to give back.

Routine

2023-11-12T00:00:00Z

I have been fortunate enough to have worked with and met a lot of great engineers in my life, and would love to meet more. I have written some personal logs on what I have learnt from each experience, but this article captures a singular pick that I have noticed with almost everyone I have met, that they all have a routine, a system. Not a timetable, not a specifically defined set of hours where they work in focus. But it’s a system they have kept or built for themselves over time where they have now become immune to changes in their environment, days and other parameters. Nothing can break their focus, their processes and their productivity.

I believe I have been able to achieve some of that myself. Here goes:

I wake up anywhere around 4 to 6 AM, that gives me a lot of control on how I steer my day ahead. Then I work on the most primary task for the day. But making sure that it needs to be wrapped up with a run before

I allow myself to be creative during these hours.

Then I return home, making myself some coffee. During this hour, I talk to my partner due to time difference. And then I get back to plan for the day, this is where I have set a strict time rule for 10AM to 4PM - no unnecessary social interactions or other dopamine hits unless for work or pre-decided. This is the time that I believe allows me to build patience and discipline. A lot of distraction due to mobile usage, social media, videos can happen during this time if not curbed.

Usually end my day after this with some logging about the day, and some light exercise, or yoga. I do some reading wherever I walk to, usually to a cafe nearby. Sometimes I like to code a little more before I sleep, but I have noticed that destroys my ability to sleep then.

Anyway, this is my process. I could wake up a little bit later, but that really doesn’t do any harm. I get right to what I would do. Maybe I will miss a focus session, I could pull that in later.

I don’t remember where I read this “To be able to do a certain thing, you have to be a certain person” or something along the lines.¹¹ If I find out where I read it, I will add it here. But this is basically what brought me to thinking about building my routine and sticking to it.

Notes from 2023 India FOSS

2023-10-29T00:00:00Z

This is most probably the only event I have attended this year and it was fun as always. Met some cool people, had some interesting conversations with students in college and how they are promoting using Linux & BSD systems within the institution. Which I like a lot. I remember my time in college, where I would introduce people around me to linux and how they would all look so baffled as to what that was. My college was third tier, that means there were not a lot of good and interested kids around me in the classes. But I would always find people like me interested in tech, met some AI people, some blockchain people throughout my college. I digress,

This year’s IndiaFoss started with the presenter talking about her personal experience with the FOSS community and how it has been a wonderful experience for her to lead the IndiaFoss movement just an year in. All the things she got to learn and other things she helped improve within the operations and tech side of things.

Then she moved on to talk about some of the technical debt that the IndiaFoss organization’s tech platform had accumulated over time due to improper management and not having enough resources to do a look back and clear things out.

Then an engineer came on-stage to talk about exactly what the organization has been upto in the last few months leading up to this event. He mentioned they have been simplifying, open sourcing the code for the main website and moving away from the frappe’s closed ecosystem for hosting that landing page, I guess. He also announced:

Foss Profile: This is kind of IndiaFoss’ version of read.cv or bento.me platforms. A collection of the digital footprint of a person to maybe build a job profile. Which can be a great talent pool considering this community has a lot of extremely excited and hardworking people.
Newsletters will be hosted on the new frappe platform. Listmonk is being used other ways unmentioned.
They are starting an ecommerce store for selling Merchandise by Jan 2024.

There were two tracks distributed in 2 auditoriums.

Session 1: Akash talks about Vyaakaran

He talks about his own programming language in 2021. Mentions compiler design course in his college. Lots of free time. A language to understand formal languages and automata theory. The course this was in is called Theory of Computation.

What is Formal Language and Automata theory? A branch of CS that deals with abstract machines (Automata) that can understand a pattern defined by a set of rules (language).

Real world applications
- Regular expressions, state machines
- Compilers, parsers
No practical, visual tools for learning about automata and formal language. Theory can feel limiting.
Why?
- Small niche
- Can be extended
- Would be useful in learning compiler design
What is Vyaakaran? A tool to visualize formal grammar, and state machines. Learn about context-free grammar.
This could be a great REPL kinda tool while making a programming language.
How?
- Built with typescript in 2022. But learnt a lot, and helping a lot of other students to learn as well.
- Vue 3 for interactive editor
- Svelte - for static
The new version could run a Turing machine.
Things he learnt
- It’s ok to reinvent the wheel.
- People will stop you. When you build, you learn more about the underneath of how things work.
- Peeling a layer of abstraction.
- Take things like a challenge. Very rewarding, even if you fail, it still makes you a better engineer.
- A FOSS project is not just a collection of files. It’s an emotion of the developers.
- Vyaakaran is a manifestation that came out of learning.
DSLs are fun
- Domain specific languages
- Used by both programmers & non-programmers.
- Can be more powerful and easier than complex UI.
Vyaakaran has it’s own DSL: Lexico (search library with operators). He made Vyaakaran open source on stage. Very good stage presence and work.

Session 2: Arpit Tripathi on Private 5G with open source 5G cores

He was a part of the first 5g usecase lab to be awarded. Yesterday Modi awarded 100 more labs.

What was the motivation?
- General usage: WiFi
- Handover between two devices is better in 5g
- Security: WPA. Uses AKA protocol.
Deployment: types
- Not every enterprise has the resources to invest. Therefore there are certain deployment models like 3gpp.
- 1st: exclusively inside the premises.
- 2nd: cloud native core functions over cloud
- 3rd: the RAN is shared. Look out for RAN?
- 4th: enterprise slice model: mentioned 5g network slicing.
Industry 4.0 goals.

Notes about the C language

2023-10-26T00:00:00Z

Notes taken while reading Beej’s guide to C.

About

Originally created to construct programs for the Unix operating system, and a flavor of C called ANSI C was also used in Plan9.
Also was then used to rewrite the Unix kernel.
Compilers for C come built in with most operating systems, eg: gcc, clang.

Language

Anything between the digraphs /* and */ is a comment. Also //.
#include tells the C Preprocessor to include a specified file.
Two stages in compilation of C code:
- Preprocessor: anything that starts with the pound sign # or “octothorpe” is handled by the Preprocessor (common /preprocessor directives/). Preprocessor processes code starting with #, output goes to the Compiler, which compiles it down to assembly.
- Compiler: rest all will be handled by the compiler.
Basic point but the stdio.h header file allows to perform bunch of I/O functionality.
The main function is called automatically when the program starts executing. Nothing else will be executed before main().
Languages that typically aren’t compiled are called interpreted languages. But as we mentioned with Java and Python, they also have a compilation step. And there’s no rule saying that C can’t be interpreted. (There are C interpreters out there!) In short, it’s a bunch of gray areas. Compilation in general is just taking source code and turning it into another, more easily-executed form.

Variable

A variable is a name for some data that’s stored in memory at some address. Looking at variables this way helps to understand pointers better (later).
Variable type needs to be defined when declaring, and that type will stay unchanged until it falls out of scope.
Always explicitly initialize variables to some values before you use them.
printf() format specifiers:

specifier	type
`%d`	integer
`%s`	string
`%f`	float
`%zu`	size_t
`%p`	pointer

C originally did not have boolean. In C, 0 means false, and any other number, for eg. 1 or -44, means true. If you #include <stdbool.h> you can also use the bool keyword.
C has a ternary operator: y += x > 10 ? 17 : 37; means

if (x > 10)
    y += 17;
else
    y += 37;

i++ & i--: the value of the expression is first computed with the value as-is. ++i & --i: this happens before the expression is evaluated.
sizeof operator is used to get the size (in bytes) of a particular expression.
- C has a special data type to represent the return value of sizeof. It’s size_t. All we know is that it’s an unsigned integer type. %zu is the format specifier for size_t.
- Also this is a compile-time operation.
switch only works with equality comparisons with constant numbers.
- Evaluates an expression to an integer value, jumps to the case that corresponds to that value. Execution continues from that point.
- If a break statement is encountered, then execution jumps out of the switch. If no break is applied, it will fall through and execute all the cases without a break.
- Is switch faster? Maybe, maybe not. But switch cannot do things like > or <= and floating point and other types.
A not-uncommon use of while loops is for infinite loops where you repeat while true:

while (1) {
    printf("1 is always true, so this repeats forever\n");
}

All three parts of a for loop are optional. An empty for loop for(;;) will run forever.

Functions

Arguments and return value types have to be predeclared.
A parameter is a special type of local variable into which the arguments are copied. Thus, a parameter is a copy of the argument, not the argument itself.
Functions will be defined before being called.
Passing by value basically means we copy the value of the argument into the parameter of the function. Unless returned, no value in the parent, for eg. main, changes.
Function prototypes look something like int foo(void); where we have created a prototype before defining the function and it’s okay to call it before definition.
Use the void keyword as parameter instead of an empty parameter list for function definitions.

Pointers

When you have a data type (like your typical int) that uses more than a byte of memory, the bytes that make up the data are always adjacent to one another in memory. Sometimes they’re in the order that you expect, and sometimes they’re not.¹¹ See endianness — byte order is a property of the platform. While C doesn’t guarantee any particular memory order (it’s platform-dependent), it’s still generally possible to write code in a way that’s platform-independent where you don’t have to even consider these pesky byte orderings.
A pointer holds the address of a data. It tells us where in memory a data point is stored.
A dereference operator is used to get the original data indirectly from the pointer variable.
&i ampersand will get the address of the variable i, it cannot be on the left side of a statement.
The main use of pointers is when you might want to return more than a single value from the execution of a function (while we know functions don’t allow multiple returns like in Go). Pointers will allow you to point to that address, data and be able to mutate it.
A question: do we always use pointers in case of complex functions? (mutating multiple values for eg.)
When using pointers, j for eg. is the address while *j will give the value at that address.
Any pointer variable of any pointer type can be set to a special value called NULL. This indicates that this pointer doesn’t point to anything.

int *p;
p = NULL;

Despite being called the billion dollar mistake by its creator, the NULL pointer is a good sentinel value and general indicator that a pointer hasn’t yet been initialized. (Of course, like other variables, the pointer points to garbage unless you explicitly assign it to point to an address or NULL.)

Array

Array length can be read inside a function with the array passed as an argument.
sizeof(int) is basically calling the sizeof fn to check on the size of the int array without creating an array.
When initializing an array you don’t need to fill the array to the size. But you definitely can’t add more.

Strings

char *s = "Hello, world!"; is a pointer initialization to the first character in the string, but is immutable. s[0] = 'z'; is not allowed. Quite the opposite when you ~char s[] = “Hello, world!”;~.
C follows a different route with implementing strings in the language, wherein it stores the bytes of a string, and marks the end of a string with a special byte called the terminator.
- A pointer to the first character in the string.
- A zero-valued byte (or NUL character) somewhere in memory after the pointer that indicates the end of the string.
- A NUL character can be written in C as \0.

Structs

Structs is a convenient way to handle data. Multiple parameters can be replaced with a single type. It basically allows a user to create types, to define data models.
struct car { ... } is how you define a struct type. ~struct car honda~ is how you define a variable of struct type car.
struct car honda = {"honda city", 123, 44} — you could initialize it this way but imagine if the order of the struct’s data is changed, that would break the whole code. Instead you could write struct car honda = {.name="honda city", .speed=123, .price=44}.
There are basically two cases when you’d want to pass a pointer to the struct as the argument to a function:
1. You need the function to be able to make changes to the struct that was passed in, and have those changes show in the caller.
2. The struct is somewhat large and it’s more expensive to copy it onto the stack than it is to just copy a pointer.
We just need to write the body. One attempt might be:

void set_price(struct car *c, float new_price) {
    c.price = new_price;  // ERROR!!
}

That won’t work because the dot operator only works on structs — it doesn’t work on pointers to structs.

Ok, so we can dereference the struct to de-pointer it to get to the struct itself, which we should be able to use the dot operator on:

void set_price(struct car *c, float new_price) {
    (*c).price = new_price;  // Works, but is ugly and non-idiomatic :(
}

So this is where the arrow operator comes in. The arrow operator helps refer to fields in pointers to structs:

void set_price(struct car *c, float new_price) {
    c->price = new_price;  // This looks so much better!
}

File I/O

Before diving into anything else:
- stdin: Standard Input, generally the keyboard by default.
- stdout: Standard Output, generally the screen by default.
- stderr: Standard Error, generally the screen by default, as well.
- These are the core I/O streams assigned to all programs or processes running on a Unix system.
Reading text files:
- Streams are generally categorized in two different ways: text and binary.
- There is a special character defined as a macro: EOF. This is what fgetc() will return when the end of the file has been reached and you’ve attempted to read another character.
- fgetc — to read a character at a time. fgets — to read lines.
Writing files:
- fputc, fputs, fprintf are basically the one-to-one similar to the readers.

Year in review, 2021

2022-01-21T00:00:00Z

This is a collection of my learnings & experiences throughout the year 2021 and the processes I want to see myself building through 2022.

Just got back from a run. I’ve been in Pune about a month now for work and this is sort of my first experience living away from the family. After having been stuck at home turning 21 in the middle of a pandemic, this felt like a great getaway. And it is. Learning so much about myself, through the habits I’ve built over the two weeks to let myself focus and form a good balance between life and work here.

It’s October, and now I have an M1 MacBook Air, my first ever Apple product. God! How are they so good with building laptops! Sitting at a cafe in Mumbai and trying to switch to this app called Bear notes for writing my blogs and I’m already loving it. It’s minimal, clean and allows me to focus on my process of writing without having to switch context too often. I can work with MarkDown, so instead of having to move my cursor to different places around the interfaces, I can very easily just keep typing in a WYSIWYG manner.

This was originally supposed to be a recording of my thoughts throughout the year, but seems like I didn’t come back very often to this page. But I still wanna include a few things I wanna reflect back on and what how I see myself moving along in 2022. As an engineer I never over-estimate or over-promise. I’ve learnt this lesson through some very practical bad experiences in product management. This keeps me and the people working with me happy and on track. I don’t plan to change my thinking about this as this has greatly benefited me in terms of my work-life balance. I’ve very rarely had to wake up until late to finish up on some work throughout 2021.

Here at the Araku Cafe in Indiranagar, Bangalore at the time of writing this para. People all around me chatting and enjoying their cups of coffee. I love being in cafes and sometimes just being an observer. Interesting how everyone sitting there is present at the same time in the same city at the same place, even though having lived completely unique lives before that point. In Bangalore, I am here to meet my team members. I personally find it refreshing to join my team and work with them in person as opposed to sitting at home at my table, with nothing but Alexa to notify me about my day. Currently, I handle the product related work. Anything from deciding what goes in and what needs to be fixed on a daily basis. What’s very new in this for me is the backend is a blockchain. Yes it’s a web3 startup and definitely wasn’t on my plan. All of it happened over a quick call with a friend and me showing interest in this ever-growing community.

Apart from learning new things, meeting new people, visiting new cities, one other thing I’ve made consistent efforts for is to be fit. I was overweight a year ago. I achieved my target weight in 2021, and I plan to keep this on and keep improving on my form and agility. I run very regularly, but recently sort of added working out and HIIT exercises to the jam. Let’s see how this goes in 2022. I will write another piece about this later, because I do have come across many engineers/designers (including all sedentary jobs) facing similar fitness issues, because of the nature of our work.

I’m still learning to make better use of my time. I’ve never really planned my days, weeks. I learnt the real value of time this year. I had never really given so much thought to my schedules, things I do in a day. But I want to, why, because I feel planning ur day sort of slows down the pace and presents the day in front of you with usually a doable enough list of tasks to get away with. You have more granular view of your day, allowing you to add slots where you can take a break every now and then, do more than just work in a day.

One more thing! I want to write more. I keep saying this and keep missing out the point, but I feel like I’ve found a rhythm and a reason now to write more about what and how I am learning things, my experiences meeting new people, traveling to new cities.