Bitcoin Checksum on Bash

Checksum is often used in Bitcoin when generating public key, address. Checksum is a simple method for error-checking data [1].

In Bitcoin blockchain the checksum is generated by running SHA256 function two times in a row.

Important note: need to use sha256 in binary mode for binary data.


Bitcoin checksum on Linux Bash: sha256sum

This is an example used on learnmeabitcoin [1] and this bash analogue gives the same result:

Which HelloWorld Is Faster: Rust, C, C++, Bourne Shell, Python3?

Which program works faster? Does Rust compiler do things extra fast? Here are our simplest programs on Rust, C, C++, Bash, Python3. They were run 100.000 times and timings are measured.



Listing HelloWorld on Rust,

fn main() {
    println!("Hello, World!");


Listing HelloWorld on C, main.c

#include <stdio.h>
int main() {
    printf("Hello, World!\n");
    return 0;


Error on `git pull`: Permission denied (publickey). fatal: The remote end hung up unexpectedly

Sometimes my Devuan unexpectedly close the session, because of some JavaScripts on websites. After re-login I cannot connect to remote git repository with errors:

$ ssh remote_server
$ git pull
Error reading response length from authentication socket.
Permission denied (publickey).
fatal: The remote end hung up unexpectedly

Some people advise to start ssh-agent and load keys to ssh-agent, but that does not work in my case:

Python: Search Beautiful Address And Its Private key On Tron Network

Tron Network has addresses that start with 'T' and have length 34 symbols. If you wish convenient address like TMYNAME93LRv...91F with 'MYNAME' string, so use my script on Python3.


TronPy Beautiful Address Generator

Generates Tron Network addresses using tronpy library and writes addresses and private keys to log.txt

Bash Script: Connect To Free VPN ProtonVPN With OpenVPN Configs

ProtonVPN allows to use Free VPN servers in Netherlands, USA, Japan. You may use official application for Linux, Android. But for fine configuring and connect just in one click need to connect with own script using OpenVPN configs by ProtonVPN. Here it is my own bash script for connect to the best protonvpn server in one click.

0. Prerequisits

Intall tor, torsocks, openvpn, resolvconf, jq

apt-get install tor torsocks openvpn resolvconf jq

Mine XMR On VPS Server Lowering CPU Usage

VPS have limited CPU and RAM usage. This is why it is hard to mine on VPS not being blocked for high consumption. I try to mine on Xeon Skylake 1 Core 2 Gb Ram.

1. Optimize Xmrig config.json

Get config.json from Xmrig wizard [1]. After first run xmrig will add many lines to your config. And you need to look at the next lines.

Under randomx object:  "mode": "light" - this makes xmrig uses 256 Mb of Ram.

Under randomx object: "1gb-pages": false - this is by default, use 2mb huge pages.

Install Raptoreum Wallet On Linux

Raptoreum is a new blockchain where you can mine with official miner or also xmrig (from 6.16 release).

1. Install dependencies

apt-get install curl build-essential libtool autotools-dev automake pkg-config python3 bsdmainutils cmake;

apt-get install python3-setuptools libcap-dev zlib1g-dev libbz2-dev


2. Building dependencies

cd depends

make -j4

cd ..


3. Building Raptoreum Core


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Get your space and put code to rocketgit. It has too simple web dashboard for create and overview your projects. Push your code and share with others.

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