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@jonleighton
jonleighton / base64ArrayBuffer.js
Last active June 17, 2025 13:46
Encode an ArrayBuffer as a base64 string
// Converts an ArrayBuffer directly to base64, without any intermediate 'convert to string then
// use window.btoa' step. According to my tests, this appears to be a faster approach:
// http://jsperf.com/encoding-xhr-image-data/5
/*
MIT LICENSE
Copyright 2011 Jon Leighton
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
@jboner
jboner / latency.txt
Last active August 9, 2025 14:54
Latency Numbers Every Programmer Should Know
Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference 0.5 ns
Branch mispredict 5 ns
L2 cache reference 7 ns 14x L1 cache
Mutex lock/unlock 25 ns
Main memory reference 100 ns 20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy 3,000 ns 3 us
Send 1K bytes over 1 Gbps network 10,000 ns 10 us
Read 4K randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD
package main
import (
"io"
"log"
"os"
"os/exec"
"io/ioutil"
"bytes"
)
@neeraj9
neeraj9 / backtrace.c
Created October 3, 2015 05:48
c code to print stack trace when program segfaults
/**
* This source file is used to print out a stack-trace when your program
* segfaults. It is relatively reliable and spot-on accurate.
*
* This code is in the public domain. Use it as you see fit, some credit
* would be appreciated, but is not a prerequisite for usage. Feedback
* on it's use would encourage further development and maintenance.
*
* Due to a bug in gcc-4.x.x you currently have to compile as C++ if you want
* demangling to work.
@yang-g
yang-g / gist:257d758cdb990eec42f8
Last active March 21, 2020 00:31
grpc pubsub c++ example
#include <iostream>
#include <grpc++/grpc++.h>
#include <grpc++/security/credentials.h>
#include "pubsub.grpc.pb.h"
int main(int argc, char** argv) {
auto channel = grpc::CreateChannel(“pubsub.googleapis.com”, grpc::GoogleDefaultCredentials());
@mrbar42
mrbar42 / README.md
Last active July 30, 2025 03:07
bash scripts to create VOD HLS stream with ffmpeg almighty (tested on Linux and OS X)

running:

bash create-vod-hls.sh beach.mkv

will produce:

    beach/
      |- playlist.m3u8
 |- 360p.m3u8
@gravitylow
gravitylow / codesign_gdb.md
Last active March 10, 2025 16:38 — forked from hlissner/codesign_gdb.md
Codesign gdb on macOS

If you are getting this in gdb on macOS while trying to run a program:

Unable to find Mach task port for process-id 57573: (os/kern) failure (0x5).
 (please check gdb is codesigned - see taskgated(8))
  1. Open Keychain Access
  2. In menu, open Keychain Access > Certificate Assistant > Create a certificate
  3. Give it a name (e.g. gdbc)
@joshtch
joshtch / gdrive-dl.py
Created January 4, 2018 02:02
Google Drive file downloader for Python, with progress bar with tqdm. Based on this SO answer https://stackoverflow.com/a/39225039/3175094
#!/usr/bin/env python2
import requests
from tqdm import tqdm
import re
import os
def download_file_from_google_drive(id, destination):
URL = 'https://docs.google.com/uc?export=download'
session = requests.Session()
@wybiral
wybiral / noscript-tracking.go
Last active October 28, 2024 23:01
Tracking cursor position in real-time with remote monitoring (without JavaScript)
// Tracking cursor position in real-time without JavaScript
// Demo: https://twitter.com/davywtf/status/1124146339259002881
package main
import (
"fmt"
"net/http"
"strings"
)
@senderle
senderle / hand-modify-pdf.md
Created September 23, 2020 15:03
So you want to modify the text of a PDF by hand

So you want to modify the text of a PDF by hand...

If you, like me, resent every dollar spent on commercial PDF tools, you might want to know how to change the text content of a PDF without having to pay for Adobe Acrobat or another PDF tool. I didn't see an obvious open-source tool that lets you dig into PDF internals, but I did discover a few useful facts about how PDFs are structured that I think may prove useful to others (or myself) in the future. They are recorded here. They are surely not universally applicable --
the PDF standard is truly Byzantine -- but they worked for my case.