Blog on Raveen Kumar

Contacts Organizer cli app

Fri, 04 Sep 2026 00:00:00 +0000

TODO:

Give your best and receive the best

Thu, 03 Sep 2026 00:00:00 +0000

Today I was speaking to a friend and I gave the best advice.

Going back on my word

Thu, 23 Oct 2025 00:00:00 +0000

So previously I mentioned that I wont use social media anymore to avoid distractions. Now I have decided to relax my rule a bit for personal reasons.

Still I will always be a blogger at heart.

New City, New me?

Thu, 23 Oct 2025 00:00:00 +0000

It’s been a while since I last wrote. Time for an update.

I landed a job at Qualcomm Bangalore after an unexpected turn of events. I’m grateful for the opportunity.

I’m still adjusting to the city and life here. Some challenges I anticipated haven’t been so difficult, while other things I expected to be easy have proven harder.

I’ve learned a lot and forgotten much in the process.

Chennai will always be my home. For now, I’ll make it here.

Quote - 1

Thu, 23 Oct 2025 00:00:00 +0000

Everybody’s after my Chainsaw heart! What about my heart?! Denji’s! Does nobody want that?!

Sticky notes

Thu, 23 Oct 2025 00:00:00 +0000

Use it. It’s an amazing invention.

Can't/Won't use Social Media anymore

Wed, 09 Apr 2025 00:00:00 +0000

I don’t know why but after using social media alternatives it’s hard for me to go back to it. Mainly websites like Reddit, LinkedIn, Instagram, X, etc., make me feel nauseous. After using BearBlog for about 3-4 years, I fell like I am fond of simple sites that focus on delivering the content to the users as simple as possible basically KISS Philosophy.

The only other Social Media that I use now is Discord and WhatsApp, it is pretty straightforward chat application with community focus. Once I find alternative to them I will leave those too.

Every damn day!

Tue, 08 Apr 2025 00:00:00 +0000

Generating Ghibli style art with ChatGPT is pretty neat

Tue, 01 Apr 2025 00:00:00 +0000

How to learn programming

Wed, 19 Mar 2025 00:00:00 +0000

F*ck around until it works

Messing around is the only way to learn programming

My favorite programming language and tools

Wed, 19 Mar 2025 00:00:00 +0000

Programming is always fun. At least for me. When I program for myself with lots of freedom, I have lots of fun. But at work not so much. There is quite a lot of restrictions and it kills me to say that I absolutely hate corporate programming.

That being said, I do enjoy some programming languages and tools that I use regularly.

Programming Languages for fun

Bash
Python
VimScript
Emacs Lisp

Programming languages I use for work

System Verilog and Verilog
UVM

Tools

Vim / Emacs
ChatGPT

Hardware

MacBook Air m1
Mac mini M2 Pro with triple monitor setup

Vim not retaining file and command history

Fri, 19 May 2023 00:00:00 +0000

This solved the problem.

https://unix.stackexchange.com/questions/43033/what-would-cause-vim-not-to-retain-command-history

Check presence and rights for ~/.viminfo. Usually that’s it which keeps command history, file editing positions, etc. One possible case is that this file belongs to root.

Unsubscribe from Emacs Org-mode mailing list

Wed, 17 May 2023 00:00:00 +0000

Visit this link and follow the instructions - https://lists.gnu.org/mailman/options/emacs-orgmode

https://emacs-orgmode.gnu.narkive.com/SrK9BVd1/o-how-i-can-unsubscribe-this-mail-list

fc fix command or fix previous command

Fri, 12 May 2023 00:00:00 +0000

In Bash, fc stands for “fix command” and it is a built-in command that allows you to work with the command history. The fc command provides a way to view, edit, and re-execute commands from your command history.

Here are some common uses of the fc command:

Viewing command history: You can use fc -l or simply fc to display the list of recently executed commands. By default, it shows the most recent commands with line numbers.

Insert a string at the beginning of all cells in a column

Wed, 10 May 2023 00:00:00 +0000

Insert a new column before it. Type this formula in the first cell and autofill the remaining,

= "New String" & A1

Copy all the required cells in the column and paste it to the original location as values.

Delete the newly inserted row.

Grep for files that does not contain a specific string

Tue, 09 May 2023 00:00:00 +0000

Another useful way to use grep is for printing file names that do not contain a specific string, for example

grep -L "string" *

You can use the -L option of the grep command, which prints the names of all files that do not contain the specified search string.

The * at the end tells grep to search all files in the current directory. If you want to search only specific files or directories, you can replace the * with the filenames or directory names.

Periodically run a program and watch the output

Fri, 05 May 2023 00:00:00 +0000

watch

Execute a program periodically, showing output fullscreen

Example

watch ls

alternative - viddy

Horizontally print file contents

Wed, 03 May 2023 00:00:00 +0000

To concatenate the contents of a vertical file horizontally in Unix, you can use the paste command with the -s option.

Here’s an example:

Let’s say you have a file file.txt with the following vertical content:

apple
banana
orange

You can concatenate the contents horizontally using the following command:

paste -s file.txt

This will produce the output:

apple   banana  orange

The -s option tells paste to concatenate the lines horizontally instead of vertically. By default, paste separates the columns with a tab character. If you want to use a different separator, you can specify it with the -d option followed by the separator character. For example:

Power of 2s

Thu, 20 Apr 2023 00:00:00 +0000

n	2^n
0	1
1	2
2	4
3	8
4	16
5	32
6	64
7	128
8	256
9	512
10	1,024
11	2,048
12	4,096
13	8,192
14	16,384
15	32,768
16	65,536
17	131,072
18	262,144
19	524,288
20	1,048,576

Reading notes - Designing a Video Game hardware in Verilog

Thu, 20 Apr 2023 00:00:00 +0000

Book: Designing Video Game Hardware in Verilog, Steven Hugg (2018).

2023-04-20-power-of-2s

Byte - 8 bits Nibble - 4 bits

/*
A clock divider in Verilog, using the cascading
flip-flop method.
*/

module clock_divider(
  input clk,
  input reset,
  output reg clk_div2,
  output reg clk_div4,
  output reg clk_div8,
  output reg clk_div16
);

  // simple ripple clock divider
  
  always @(posedge clk)
    clk_div2 <= reset ? 0 : ~clk_div2;

  always @(posedge clk_div2)
    clk_div4 <= ~clk_div4;

  always @(posedge clk_div4)
    clk_div8 <= ~clk_div8;

  always @(posedge clk_div8)
    clk_div16 <= ~clk_div16;

endmodule

Static timing anaysis

Setup time and hold time are timing constraints that must be met in digital circuits to ensure correct data transfer between logic elements. These constraints are important to consider in the design of synchronous digital circuits, which use a clock signal to synchronize the transfer of data between flip-flops or other storage elements.

Emacs symbol search at point

Wed, 12 Apr 2023 00:00:00 +0000

To enter symbol search press M-s . this with execute isearch-forward-symbol-at-point function. This is similar to vim’s * key. I accitentally pressed it instead of M-s h . and found it while trying to highlight a symbol, lol.

Mark ring and Jumplist with emacs and helm

Fri, 07 Apr 2023 00:00:00 +0000

Like vim, emacs has an alternative to jump list. It is called mark rings but its difficult to use. Fortunately there is a helm and counsel function to help us navigate the mark rings. Add this following command to emacs init file,

(global-set-key (kbd "C-c '") 'helm-all-mark-rings)

I use C-c ' to browse mark rings.

Stop asking tags table to be reset every time a new file is visited in a different project

Fri, 07 Apr 2023 00:00:00 +0000

(setq tags-add-tables nil)

Emacs configuration for perl programming

Fri, 03 Mar 2023 00:00:00 +0000

Configuration taken from https://www.emacswiki.org/emacs/CPerlMode

;;; Perl
;; cperl-mode is preferred to perl-mode
;; "Brevity is the soul of wit" <foo at acm.org>
(defalias 'perl-mode 'cperl-mode)
(setq cperl-invalid-face nil) 
(setq cperl-electric-keywords t) ;; expands for keywords such as foreach, while, etc...
(setq cperl-hairy t) ;; Turns on most of the CPerlMode options

Python docstrings

Tue, 28 Feb 2023 00:00:00 +0000

In python, docstrings are used to define the functions documentation. Refer this page,

https://peps.python.org/pep-0257/


def function(a, b):
    """Do X and return a list."""

Git hangs on git pull or git fetch

Mon, 27 Feb 2023 00:00:00 +0000

Sometime I find git hanging in wsl and it is not able to recover. The only way to recover is restarting the computer.

How-to delete an element from a xml tree in Python

Mon, 27 Feb 2023 00:00:00 +0000

Following are the steps to delete an element from a xml tree proprly when parsing with python,

https://stackoverflow.com/questions/47041688/remove-element-from-xml-with-elementtree

Example XML tree


<foo>
   <bar>
      <level>
         <test name="1">
            <stuff>
               hello
            </stuff>
         </test>
         <test name="2">
            <stuff>
               hello
            </stuff>
         </test>
      </level>   
   </bar>
</foo>

Python code to delete stuff


import xml.etree.ElementTree as ET

tree = ET.parse('myfile.xml')
root = tree.getroot()

for test in root.iter('test'):
    for stuff in test.findall('stuff'):
       test.remove(stuff)

print ET.tostring(root)

You need to have pointer to parent tag in order to remove child tag.

Fuzzy matching with python

Sun, 26 Feb 2023 00:00:00 +0000

Fuzzy matching is great. In fact, it is better than regular expression matching in certain cases. Come to think of it, our entire human brain works on fuzzy matching.

Take handwriting, for example, everyone can read each other’s handwriting as long as it’s legible. That’s fuzzy matching on an organic level.

I had a problem where I have a string of text, and I wanted to match the substring with other string but the issue is that the substring varies from string to string and I cant predict the proper substring to do a regex matching. So suddenly out of the blue I got an idea to do a fuzzy matching.

rsync is weird, does not sync "tags" directory

Fri, 24 Feb 2023 00:00:00 +0000

For whatever reason rsync decided not to sync tags directory since it is ignored in CVS mode. Took a lot time to figure out the problem. Finally this command works correctly.

--include used to sync everything, despite ofthe cvs option, -C. But removed in this command.

	rsync -av --delete --checksum --copy-links -rPuzhi ./public/ root@raveenkumar.xyz:/var/www/raveenkumar/

Ask bing

Thu, 23 Feb 2023 00:00:00 +0000

Today I got access to bing chat feature. Finally AI search is here, lets see how well this goes. Based on my chat it seems much dumber than chatgpt.

Emacs keybindings work on macos

Thu, 23 Feb 2023 00:00:00 +0000

I was suprised to find out that when I accidentally pressed ctrl-k on a line it killed it in macos. Looks like some emacs keybindings are supported system wide by default.

http://irreal.org/blog/?p=259

Explained in this blog post.

【Ctrl+f】, 【Ctrl+b】, 【Ctrl+a】, 【Ctrl+e】, 【Ctrl+k】, 【Ctrl+y】, 【Ctrl+p】, 【Ctrl+n】, and a few others work across the whole system.

Killed it

Tue, 21 Feb 2023 00:00:00 +0000

Adding epiog to python scripts using argparse module

Mon, 20 Feb 2023 00:00:00 +0000

https://docs.python.org/dev/library/argparse.html#argparse.RawDescriptionHelpFormatter

We can add epilog to argparse help and description to add more info. Refer link above.

Emacs File-info package

Mon, 20 Feb 2023 00:00:00 +0000

Found a new package today. Does exactly what I want. List and copy the file info and path with a keybind and a popup window.

https://github.com/Artawower/file-info.el

Installation:

Add this to you init.el file

;; File-info
(use-package hydra
  :straight t)
(use-package browse-at-remote
  :straight t)
(use-package posframe
  :straight t)
(use-package file-info
  :straight (:host github :repo "artawower/file-info.el")
  :bind (("C-c f i" . 'file-info-show))
  :config
  (setq hydra-hint-display-type 'posframe)
  (setq hydra-posframe-show-params `(:poshandler posframe-poshandler-frame-center
                                               :internal-border-width 2
                                               :internal-border-color "#61AFEF"
                                               :left-fringe 16
                                               :right-fringe 16)))

Emacs wrap region package

Mon, 20 Feb 2023 00:00:00 +0000

https://github.com/rejeep/wrap-region.el

Wrap Region is a minor mode for Emacs that wraps a region with punctuations. For “tagged” markup modes, such as HTML and XML, it wraps with tags.

How to copy paste as plain text into gmail on ios

Mon, 20 Feb 2023 00:00:00 +0000

https://apple.stackexchange.com/questions/354992/how-to-copy-and-paste-as-plain-text-on-ios

Paste formatted
Select the just pasted text and in the context menu swipe right and tap on “Share…”
In the Share sheet, tap on “Copy”. This copies as plain text!
Tap still selected text to get the context menu again
In the context menu tap on “Paste” to replace the selected, formatted text with its plain text representation

Recursively grep with emacs lisp only

Mon, 20 Feb 2023 00:00:00 +0000

I was looking for a way to recursively grep inside a directory and a find-grep replacement since its not availabe in windows and I found this.

https://www.reddit.com/r/emacs/comments/bxtwfg/grep_and_find_but_in_pure_emacs_lisp/

(project-find-regexp)

Copy and paste as plain text into gmail on ios

Fri, 17 Feb 2023 00:00:00 +0000

When you copy text anywhere in the browser from an ios device, it is a formatted text. To paste is as a plain text do the following.

Paste formatted
Select the just pasted text and in the context menu swipe right and tap on “Share…”
In the Share sheet, tap on “Copy”. This copies as plain text!
Tap still selected text to get the context menu again
In the context menu tap on “Paste” to replace the selected, formatted text with its plain text representation

Reference:

Example pstree command

Fri, 17 Feb 2023 00:00:00 +0000

pstree -u username -hp

Advising a function in emacs lisp

Thu, 16 Feb 2023 00:00:00 +0000

One of the awesome things that I found when programming in elisp is the advice. For any function, you can advice before, after, around, to it.

When you advice a function A with a function B. Function B will executed before it. This is really interesting and useful.

(advice-add 'funa :before 'funb)

EMACS is a event based program, it has hooks, advices and all that goodness to modify and customize anything. 🪝

Insert video with hugo shortcode

Thu, 16 Feb 2023 00:00:00 +0000

https://dev.to/hi_artem/add-a-video-to-your-hugo-website-104

To create a new shortcode, place its template in the layouts/shortcodes. In my case, I created the following template at layouts/shortcodes/video.html

<div class="container">
  <div id="player-wrapper" class="{{ .Get 1 }}"></div>
</div>

<script 
  type="text/javascript" 
  src="https://cdn.jsdelivr.net/npm/@clappr/player@latest/dist/clappr.min.js"
>
</script>

<script>
  var playerElement = document.getElementById("player-wrapper");

  var player = new Clappr.Player({
    source: {{ .Get 0 }},
    mute: true,
    height: 360,
    width: 640
  });

  player.attachTo(playerElement);  
</script>

Now, I can create a new Markdown document, and use the newly created shorthand. Two arguments has to be provided: link to the video, and CSS class to apply to the container wrapping the video element.

Open new eshell buffer without closing the current one

Thu, 16 Feb 2023 00:00:00 +0000

I usually run multiple shell instances in terminal. If you already have one eshell buffer open. You can use prefix command to open a new eshell buffer without closing the current one.

C-u M-x eshell

https://stackoverflow.com/questions/2540997/create-more-than-one-eshell-instance-in-emacs/75480565#75480565

Here is my implementation of new eshell buffer / instance.

(defun eshell-new-buffer (args)
  "Create a new eshell buffer."
  (interactive "P")
  (eshell "new")
  )


(global-set-key (kbd "C-c e e") 'eshell)

(global-set-key (kbd "C-c e n") 'eshell-new-buffer)

Command-line ChatGPT

Wed, 15 Feb 2023 00:00:00 +0000

Here I have written a python script that will take user input string and ask OpenAI text generator to generate text.

https://raw.githubusercontent.com/raveensrk/dotfiles-main/main/stow/.scripts/chatgpt.py

I should probably try writing a elisp code for this.

Don't setup your own mail server

Wed, 15 Feb 2023 00:00:00 +0000

Setting up a mail server is much more difficult than setting up a website. And I spent a lot of time figuring out why my mails were not being sent. It was a good learning experience. That’s all it was. I switched back to gmail.

Copy paste org tables into confluence with proper formatting

Wed, 08 Feb 2023 00:00:00 +0000

Copy paste org tables into confluence

Select all org table replace + with | in header seperator and copy paste into confluence page and it will automatically convert to tables.

Thoughts on Cristiano Ronaldo

Wed, 08 Feb 2023 00:00:00 +0000

All I ever wanted was to see Ronald win the World Cup but that did not happen today. Portugal got eliminated in the quarter finals by Morocco.

Why am I a fan of ronado?

Well as a kid when I started playing football I wanted to watch others play and learn from them like everyone else. I was also playing fifa 2002 and fifa 99 I think. At that time I did not know anything about that. After I got a good pc I installed fifa 2007 and I was a Manchester United fan based on the previous games because they used to have a better rating and good stat players.

Emacs Conf 2022

Fri, 03 Feb 2023 00:00:00 +0000

EMACS conf 2022

My Third Post

Fri, 03 Feb 2023 00:00:00 +0000

This is my third post

Third post

Connect magic mouse to windows pc

Thu, 02 Feb 2023 00:00:00 +0000

connect magic mouse to windows pc

https://www.switchingtomac.com/tutorials/how-to-set-up-and-use-the-magic-mouse-on-windows/

My Second Post

Thu, 02 Feb 2023 00:00:00 +0000

This is my second post

Is hugo good? Feels complicated.

Rocket man.