darcyliu

# OS release info
uname -s
uname -r
uname -n

# Start up time
uptime

# CPU info
cat /proc/stat

darcyliu

pkg install -y wireguard wireguard-tools

cd /usr/local/etc/wireguard/
umask 077

wg genkey > freebsd.private
wg pubkey < freebsd.private > freebsd.public

wg genkey > client.private
wg pubkey < client.private > client.public

darcyliu

#!/bin/bash
set -e;

# Set up a single-node Kubernetes system on Debian 10 (Buster).
# Use Flannel as the network fabric. Install the Kubernetes
# dashboard.

# disable swap
swapoff -a;

darcyliu

package main

import (
	"net/http"
	"fmt"
	"log"
	"flag"
	"net"
	"time"
	"runtime"

darcyliu

@implementation UIImage (Helpers)
- (UIImage *)scaleImageToSize:(CGSize)newSize
{
    UIGraphicsImageRenderer *renderer = [[UIGraphicsImageRenderer alloc] initWithSize:newSize];
    UIImage *image = [renderer imageWithActions:^(UIGraphicsImageRendererContext*_Nonnull myContext) {
        [self drawInRect:(CGRect) {.origin = CGPointZero, .size = newSize}];
    }];
    return image;
}

darcyliu

#import <objc/runtime.h>

NSArray *AllImageNames() {
    unsigned int imageCount = 0;
    const char **imageNames = objc_copyImageNames(&imageCount);
    NSMutableArray<NSString *> *imageNameStrings = [[NSMutableArray alloc] initWithCapacity:imageCount];
    if (imageNames!=NULL) {
        for (unsigned int i = 0; i < imageCount; i++){
            const char *imageName = imageNames[i];
            NSLog(@"image name: %s", imageNames[i]);

darcyliu

// mutex example
// clang++ hello.cpp -std=c++11 -o hello
#include <iostream>       // std::cout
#include <thread>         // std::thread
#include <mutex>          // std::mutex

std::mutex mtx;           // mutex for critical section

void print_block (int n, char c) {
  // critical section (exclusive access to std::cout signaled by locking mtx):

darcyliu

// clang attribute.c -o attribute
#include <stdio.h>
int main(int argc, char *argv[]) {
    printf("Hello World!\n");
    return 0;
}

__attribute__((constructor)) static void beforeFunction()
{
    printf("beforeFunction\n");

darcyliu

//
//  PriorityQueue.h
//  PriorityQueue
//
//  Created by Darcy Liu on 2018/11/6.
//  Copyright © 2018 Darcy Liu. All rights reserved.
//

#import <Foundation/Foundation.h>

darcyliu

// go get golang.org/x/net/webdav
// go run files.go -openbrowser -http=127.0.0.1:9090
package main

import (
	"context"
	"flag"
	"net/http"
	"log"
	"fmt"