Discover gists

Debian 13

Caution Upgrading from Debian 12 to Debian 13 on machines with mdadm has intermittently failed for me; symptom is that grub EFI is not up to date and system boots into BIOS. Root cause under investigation; it might not be related to mdadm.

To start, read the official release notes.

If your install fits into "vanilla Debian plus maybe a handful of 3rd-party repos", then this guide for a simple upgrade to Debian 13 "trixie" from Debian 12 "bookworm" can be helpful. 3rd-party repos are handled with a find command.

Note upgrade is only supported from Debian 12 to Debian 13. If you are on Debian 11, upgrade to Debian 12 first. Then once on Debian 12, you can upgrade to Debian 13.

Creating additional virtual hard disk (VHDX) for WSL2 with ext4 filesystem

Lines starting with # mean the commands have to be executed by root user under Linux shell (WSL distro). All other commands have to be executed under Windows-PowerShell as Administrator.

Make VHDX disk file and mount it under Windows

New-VHD support.vhdx -SizeBytes 25GB -Dynamic -BlockSizeBytes 1MB
Write-Output "\\.\PhysicalDrive$((Mount-VHD -Path support.vhdx -PassThru | Get-Disk).Number)"

Google dork cheatsheet

Search filters

Filter	Description	Example
allintext	Searches for occurrences of all the keywords given.	`allintext:"keyword"`
intext	Searches for the occurrences of keywords all at once or one at a time.	`intext:"keyword"`
inurl	Searches for a URL matching one of the keywords.	`inurl:"keyword"`
allinurl	Searches for a URL matching all the keywords in the query.	`allinurl:"keyword"`
intitle	Searches for occurrences of keywords in title all or one.	`intitle:"keyword"`

1. Update your system

First, run the apt command to apply security updates:

sudo apt update
sudo apt upgrade

2. Download and run openvpn-install.sh script

DOwnload installation script using short url as follow and update chmod :

wget https://git.io/vpn -O openvpn-ubuntu-install.sh

	/* List of LAMBDA functions in this collection:
	--------------------------------------------
	ISPRIME -------->> Determines if a number is prime.
	FACTORS -------->> Returns all factors of a number.
	PF ------------->> (recursive) Returns the prime factorization of a number.
	PF_LCM --------->> Returns the least common multiple of integers. Extends the native LCM return limits from 2^53 to 10^308.
	*/


	/* FUNCTION NAME: ISPRIME

	/* List of LAMBDA functions in this collection:
	--------------------------------------------
	CALENDARRAY ---->> Generates a monthly calendar for the specified number of months.
	CROSSJOIN ------>> Returns the Cartesian product of two tables or arrays.
	CROSSJOINM ----->> Returns the Cartesian product of multiple arrays.
	KRON ----------->> Returns the Kronecker product of two arrays.
	PERMA ---------->> Returns all permutations or combinations, with or without repetitions, for a given number of items.
	REPTA ---------->> Repeats a range or array vertically or horizontally a specified number of times.
	REPTROWS ------->> Repeats each row in a range or array a specified number of times.
	REPTCOLS ------->> Repeats each column in a range or array a specified number of times.

	/* List of LAMBDA functions in this collection:
	--------------------------------------------
	LISTBY --------->> Groups all values from a table or array by distinct item and returns a jagged array of associated lists.
	INSTANCENUM ---->> Returns the running count of distinct items in an unordered table or array.
	RUNNINGTOT ----->> Returns the running total of values by distinct item in an unordered table or array.
	RUNNINGTOT2 ---->> Returns the running total of values by distinct item in an unordered table or array, with the option to prioritize order by date.
	JOINROWS ------->> Creates a key identifier row by combining the values of each row in an array on a column-by-column basis.
	JOINCOLS ------->> Creates a key identifier field by combining the values of each column in an array on a row-by-row basis.
	SCANBYROW ------>> Scans an array in row-major order by applying a LAMBDA to each value and returns an array of intermediate results for each row.
	SCANBYCOL ------>>

	// clang-format off
	/*
	* SPDX-License-Identifier: MIT
	* Copyright (c) 2025 Tetsuo AI
	*
	* tetsuo_curl.c - A minimal curl-like HTTP client using the Simple API
	*
	* Demonstrates how little code is needed for a functional HTTP client.
	* Redirects are followed automatically (up to 10 hops).
	*

	# calculation are based on http://www.esreality.com/index.php?a=post&id=1945096
	# assuming windows 10 uses the same calculation as windows 7.
	# guesses have been made calculation is not accurate
	# touchpad users make sure your touchpad is calibrated with `sudo libinput measure touchpad-size`
	# import matplotlib.pyplot as plt
	import struct

	# set according to your device:
	xinput_device_id = 13
	device_dpi = 1000 # mouse dpi

	[
	{"name": "Afghanistan", "code": "AF"},
	{"name": "land Islands", "code": "AX"},
	{"name": "Albania", "code": "AL"},
	{"name": "Algeria", "code": "DZ"},
	{"name": "American Samoa", "code": "AS"},
	{"name": "AndorrA", "code": "AD"},
	{"name": "Angola", "code": "AO"},
	{"name": "Anguilla", "code": "AI"},
	{"name": "Antarctica", "code": "AQ"},