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Getting started with Linux kernel development

Prerequisites

The Linux kernel is written in C, so you should have at least a basic understanding of C before diving into kernel work. You don't need expert level C knowledge, since you can always pick some things up underway, but it certainly helps to know the language and to have written some userspace C programs already.

It will also help to be a Linux user. If you have never used Linux before, it's probably a good idea to download a distro and get comfortable with it before you start doing kernel work.

Lastly, knowing git is not actually required, but can really help you (since you can dig through changelogs and search for information you'll need). At a minimum you should probably be able to clone the git repository to a local directory.

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/* bookmarks are stored in “/data/data/org.mozilla.firefox/files/mozilla/…….default/browser.db” */
SELECT url, created
FROM bookmarks
WHERE COALESCE(url, '') <> ''
ORDER BY created ASC

alxbnct

https://code.google.com/p/android/issues/detail?id=32696#c5

If you have a certificate that is not
trusted by Android, when you add it, it goes in the personal cert store.
When you add a cert in this personal cert store, the system requires a
higher security level to unlock the device. But if you manage to add your
cert to the system store then you don't have this requirement. Obviously,
root is required to add a certificate to the system store, but it is quiet
easy.

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;;; The Y Combinator explained in scheme.
;;; with credits to:
;;;   https://mvanier.livejournal.com/2897.html
;;; Status: WIP

(define fibonacci
  (lambda (n)
    (cond ((= n 0) 0)
          ((= n 1) 1)
          (else (+ (fibonacci (- n 1)) (fibonacci (- n 2)))))))

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Exposing your clipboard over SSH

I frequently administer remote servers over SSH, and need to copy data to my clipboard. If the text I want to copy all fits on one screen, then I simply select it with my mouse and press CMD-C, which asks relies on m y terminal emulator (xterm2) to throw it to the clipboard.

This isn't practical for larger texts, like when I want to copy the whole contents of a file.

If I had been editing large-file.txt locally, I could easily copy its contents by using the pbcopy command:

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#!/bin/bash
#Simple Firewall Script.
#Add "pre-up iptables-restore < /etc/iptables.rules" to /etc/network/interfaces

#Setting up default kernel tunings here (don't worry too much about these right now, they are acceptable defaults) #DROP ICMP echo-requests sent to broadcast/multi-cast addresses.
echo 1 > /proc/sys/net/ipv4/icmp_echo_ignore_broadcasts
#DROP source routed packets
echo 0 > /proc/sys/net/ipv4/conf/all/accept_source_route
#Enable TCP SYN cookies
echo 1 > /proc/sys/net/ipv4/tcp_syncookies

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#!/bin/sh

# inspired by https://www.tumfatig.net/20190131/customized-resolution-for-openbsd-in-virtualbox/

if [ "$(id -u)" -ne 0 ]; then
    echo "This script must be run as root"
    exit 1
fi

mkdir -p /etc/X11/xorg.conf.d

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#!/bin/sh

if [ -z "$1" ] || [ -z "$2" ]; then
	echo "Pass VBox machine name and screen resolution"
	echo "Example: 'OpenBSD New' '1920x1080x32'"
	exit 1
fi

VBoxManage setextradata "$1" CustomVideoMode1 "$2"

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server:
    ###########################################################################
    # BASIC SETTINGS
    ###########################################################################
    # Time to live maximum for RRsets and messages in the cache. If the maximum
    # kicks in, responses to clients still get decrementing TTLs based on the
    # original (larger) values. When the internal TTL expires, the cache item
    # has expired. Can be set lower to force the resolver to query for data
    # often, and not trust (very large) TTL values.
    cache-max-ttl: 86400

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Google

• "cocotte bag": exact match
• "* is thicker than water": * to replace a phrase inside exact match
• jaguar -car: minus to filter out matches
• site:time.com google: search on site, you don't need '.', e.g. 'site:gov'
• define:bae: check definition, even for slang
• $0..$50: numeric range (ignore $)
• "inbound marketing" ~professional: synonyms
• related:nationalgeographic.com: similar sites