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@bastman
bastman / docker-cleanup-resources.md
Created March 31, 2016 05:55
docker cleanup guide: containers, images, volumes, networks

Docker - How to cleanup (unused) resources

Once in a while, you may need to cleanup resources (containers, volumes, images, networks) ...

delete volumes

// see: https://github.com/chadoe/docker-cleanup-volumes

$ docker volume rm $(docker volume ls -qf dangling=true)

$ docker volume ls -qf dangling=true | xargs -r docker volume rm

@rubensayshi
rubensayshi / gist.md
Last active May 2, 2024 04:00
Bitcoin Script Overview

rundown of different scripts and what is what and what goes where.

  • the prevoutScript is the script of the output being spend
  • the redeemScript is the script that is used to solve the P2SH
  • the signatureScript is the script that is taken into the signatureHash for signing
  • the witnessRedeemScript is the script that is used to solve the P2WSH
  • the scriptSig is what goes into the input.scriptSig when serializing the TX
  • the witnessScript is what goes into the input.witness when serializing the TX

for a P2KH

@0mkara
0mkara / Ethereum_private_network.md
Last active March 30, 2025 21:48
Ethereum private network configuration guide.

Create your own Ethereum private network

Introduction

Used nodes:

Linux raspberrypi 4.9.41-v7+ #1023 SMP Tue Aug 8 16:00:15 BST 2017 armv7l GNU/Linux
Linux localhost.localdomain 4.14.5-200.fc26.x86_64 #1 SMP Mon Dec 11 16:29:08 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux
@daniel-j-h
daniel-j-h / pgo.sh
Last active February 14, 2025 07:28
pgo: profile guided optimization with gcc
# Instrument binaries, pgo data to /data/pgo, serial make is important to not confuse the pgo generator
env CXXFLAGS='-march=native -fprofile-dir=/data/pgo -fprofile-generate=/data/pgo' cmake .. -DCMAKE_BUILD_TYPE=Release
make -j 1
# Run instrumented program, generate and write pgo data
./runIt
# Use profile data and feed into gcc, correct for threading counter noise, serial make is important to not confuse the pgo generator
env CXXFLAGS='-march=native -fprofile-dir=/data/pgo -fprofile-use=/data/pgo -fprofile-correction' cmake .. -DCMAKE_BUILD_TYPE=Release
make -j 1
@xrstf
xrstf / letsencrypt.md
Last active October 30, 2024 07:03
Let's Encrypt on Ubuntu 14.04, nginx with webroot auth

Let's Encrypt on Ubuntu 14.04, nginx with webroot auth

This document details how I setup LE on my server. Firstly, install the client as described on http://letsencrypt.readthedocs.org/en/latest/using.html and make sure you can execute it. I put it in /root/letsencrypt.

As it is not possible to change the ports used for the standalone authenticator and I already have a nginx running on port 80/443, I opted to use the webroot method for each of my domains (note that LE does not issue wildcard certificates by design, so you probably want to get a cert for www.example.com and example.com).

Configuration

For this, I placed config files into etc/letsencrypt/configs, named after <domain>.conf. The files are simple:

module type CELL = sig
type 'a cell
type 'a exp
val return : 'a -> 'a exp
val (>>=) : 'a exp -> ('a -> 'b exp) -> 'b exp
val cell : 'a exp -> 'a cell exp
val get : 'a cell -> 'a exp
@ethers
ethers / call-then-sendtx-pattern.js
Last active July 24, 2020 05:51
call-then-sendtx pattern for Ethereum Dapps
/*
In Ethereum, a contract can be written so that it returns a value for eth_call.
A Dapp can then check for success or error value of eth_call, before calling eth_sendTransaction,
to take advantage of eth_call effectively being a "preview" of the code flow that the transaction
will take. In traditional client-server, clients can't ask servers beforehand what's going to
happen when the client makes a call; with Dapps contracts can be written so that clients can ask
for a "preview" of what is going to happen, before any funds/ethers are actually utilized
(eth_call does not cost any ethers).
Note: it is possible that in between eth_call and when eth_sendTransaction is actually mined,
@vayn
vayn / decrypt.py
Last active October 9, 2017 22:16
Example of PyCrypto AES decryption
import base64
import hashlib
import hmac
from Crypto.Cipher import AES
key = base64.decodebytes(b'v4QC6l4ttEogiBYvjLyvbA==')
nonce = base64.decodebytes(b'3iNVHJXuCfYoU9QP49DGqw==')
ct = base64.decodebytes(b'x9WM3Qy15Xw/2Z6pGVKXVA==')