hewigovens

Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns
L2 cache reference ........................... 7 ns
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns             
Compress 1K bytes with Zippy ............. 3,000 ns  =   3 µs
Send 2K bytes over 1 Gbps network ....... 20,000 ns  =  20 µs
SSD random read ........................ 150,000 ns  = 150 µs

Read 1 MB sequentially from memory ..... 250,000 ns = 250 µs

hewigovens

/*
	pipe_source.m
	
	clang pipe_source.m -o pipe -framework Foundation -D [ USE_SOURCE | USE_IO | USE_FILEHANDLE [ FILEHANDLE_READABILITY | FILEHANDLE_WAIT ] ]
 */

#import <Foundation/Foundation.h>

int main(void) {
	enum RunLoop {

hewigovens

Updates without submitting to App Store

This is allowed for ReactNative apps. Source

AppHub.io is one option, open source coming soon.

Building a ReactNative app with Swift

See facebook/react-native#2648

hewigovens

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple Computer//DTD PLIST 1.0//EN"
"http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
    <dict>
        <key>Label</key>
        <string>in.fourplex.aria2</string>
        <key>ProgramArguments</key>
        <array>
            <string>/usr/local/bin/aria2c</string>

hewigovens

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <libproc.h>

int main (int argc, char* argv[])
{
    int ret;
    pid_t pid; 

hewigovens

# create a symlink to avoid the the ugly-long-hard-remember derived data path like:
# ~/Library/Developer/Xcode/DerivedData/XXXXXX-aeuhuddtlmcrpvczljaagufyzgpw/Build/Products/Debug/

if [ -L build ];then
  rm -rf build
fi

if [ ! -d build ]; then
    ln -s "${BUILT_PRODUCTS_DIR}" build
fi

hewigovens

NSString* getInternalDiskSN()
{
    NSString* result = @"";
    
    CFMutableDictionaryRef matching;
    matching = IOServiceMatching("IOAHCIBlockStorageDevice");
    io_service_t service = IOServiceGetMatchingService(kIOMasterPortDefault, matching);
    if (service) {
        CFMutableDictionaryRef properties = NULL;

hewigovens

#!/bin/sh

find . -name "*.pbxproj" -exec sed -i "*.bak" '/GCC_VERSION/d' {} \;
find . -name "*.pbxproj" -exec sed -i "*.bak" '/SDKROOT =/d' {} \;
find . -name "*.pbxproj" -exec sed -i "*.bak" '/MACOSX_DEPLOYMENT_TARGET =/d' {} \;

hewigovens

#!/bin/sh
SDK=`dirname $0`
SCRIPT=`basename $0`
SDKPARENT=`dirname $SDK`
DEVROOT=`xcode-select --print-path`
SDKVER=`xcodebuild -showsdks | grep iphoneos | awk '{print $2}' | tail -n 1`
SDKROOT="$DEVROOT/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS$SDKVER.sdk"
SDKsROOT="$DEVROOT/Platforms/iPhoneOS.platform/Developer/SDKs"

PLATFORM=`uname -sp`

hewigovens

#include <stdio.h>
#include <curl/curl.h>

int main(void)
{
    CURL *curl;
    CURLcode ret;
    char* resolved_url = NULL;
    curl = curl_easy_init();
    if(curl)