h4k1m0u

Install dependencies

$ npm install

Run on webbrowser

$ npm start

h4k1m0u

#include <stdio.h>
#include <stdlib.h>

#include <unistd.h>
#include <sys/wait.h>

int main() {
  const int n_processes = 5;
  pid_t pid;    

h4k1m0u

#include <stdio.h>
#include <unistd.h>
#include <stdbool.h>

/* https://www.gnu.org/software/libc/manual/html_node/Example-of-Getopt.html */
int main(int argc, char* argv[]) {
  bool is_a = false;
  bool is_b = false;
  bool is_c = false;
  char* value_b = "";

h4k1m0u

#include <stdio.h>
#include <string.h>

#include <sys/socket.h>
#include <netdb.h>
#include <arpa/inet.h>
#include <netinet/in.h>

/**
 * Find ipv4 addresses (tcp) associated with given hostname

h4k1m0u

#include <stdio.h>

/* Inspired by: https://hackaday.com/2022/03/16/linux-fu-simple-pipes/ */
int main() {
  // creates a pipe between calling pgm & executed command (`ls`) and
  // returns a stream to read from the pipe
  FILE* pipe = popen("ls -l", "r");

  // read the output of shell command from stream
  char buffer[64];

h4k1m0u

#include <stdio.h>
#include <time.h>
#include <math.h>

/* https://www.educative.io/edpresso/what-is-clockt-in-c */
int main() {
  clock_t start_ticks = clock();

  size_t n_iters = pow(10, 9);
  for (size_t i = 0; i < n_iters; i++) {

h4k1m0u

Server

• Each time a client connects, a message entered by the user is sent to it
• Can serve multiple clients simultaneously using processes, while still waiting for other incoming connections

Client

• Receives the same message 10 times from the server
• Disconnects automatically once the server goes down

h4k1m0u

git log --pretty=format:'%ad - %s' --date=human

h4k1m0u

// file: src/main.cpp
#include <iostream>

#include "glad/glad.h"
#include "window.hpp"

#include "nanovg.h"
#define NANOVG_GL3_IMPLEMENTATION
#include "nanovg_gl.h"

h4k1m0u

XCB

• Client-side of X11 display server (replacement for xlib), stands for X protocol C-language Binding.
• Check the [official tutorial][xcb-tutorial].

Terminology

From this [Stackoverflow question][stackoverflow]:

• Each X server has one display identified by a display number (by default 0).
• A display is a collection of monitors (screens) sharing the same input devices (keyboard, mouse).
• Multi-user systems have multiple displays, so that more than one person can do graphic work. For instance, two users connected to the GUI of the same machine will have different values for $DISPLAY variable.