Bouni

• Video by MetalMusings https://www.youtube.com/watch?v=NQ-HnrusGJo
• Linked LinuxCNC Forum Post https://forum.linuxcnc.org/10-advanced-configuration/42048-notes-from-installation-of-ethercat-on-raspberry-pi-4

The folowing is a writup from Hakans forum post!

RPi Setup

1. Download & Write image to SD card: www.linuxcnc.org/iso/linuxcnc-2.8.1-pi4.zip
2. Configure Wifi via wpa_supplicant.conf
3. Put SD card into RPi and verify that RT-PREEMT Kernel is running: uname -a
4. Update everything and reboot: sudo apt update && sudo apt upgrade && sudo reboot

fay59

Here's a list of mildly interesting things about the C language that I learned mostly by consuming Clang's ASTs. Although surprises are getting sparser, I might continue to update this document over time.

There are many more mildly interesting features of C++, but the language is literally known for being weird, whereas C is usually considered smaller and simpler, so this is (almost) only about C.

1. Combined type and variable/field declaration, inside a struct scope [https://godbolt.org/g/Rh94Go]

struct foo {
   struct bar {
 int x;

andreibosco

Source: https://apple.stackexchange.com/questions/138941/how-do-i-stop-the-adobe-creative-cloud-app-from-auto-launching-on-login

It is loaded by default by /Library/LaunchAgents/com.adobe.AdobeCreativeCloud.plist.

If you run

launchctl unload -w /Library/LaunchAgents/com.adobe.AdobeCreativeCloud.plist

tobert

G1GC v.s. CMS for Cassandra 2.0

Many people have asked me about using the G1 garbage collector with Cassandra. Since most of my customers are running 2.0 in production the test is with 2.0 for now. Once I script it up I'll re-run the numbers with 2.1.

I also need to re-test with Java 7 and the Oracle JDKs.

TL;DR

kristopherjohnson

import UIKit

/// Wrapper for the NSNotification userInfo values associated with a keyboard notification.
///
/// It provides properties that retrieve userInfo dictionary values with these keys:
/// 
/// - UIKeyboardFrameBeginUserInfoKey
/// - UIKeyboardFrameEndUserInfoKey
/// - UIKeyboardAnimationDurationUserInfoKey
/// - UIKeyboardAnimationCurveUserInfoKey

chrisgibson

import scala.concurrent.{ExecutionContext, Future}
import spray.routing.{AuthenticationFailedRejection, RequestContext}
import spray.routing.authentication.{Authentication, ContextAuthenticator}

/** Token based authentication for Spray Routing.
  * 
  * Extracts an API key from the header or querystring and authenticates requests.
  * 
  * TokenAuthenticator[T] takes arguments for the named header/query string containing the API key and
  * an authenticator that returns an Option[T]. If None is returned from the authenticator, the request

dypsilon

Frontend Development

Attention: the list was moved to

https://github.com/dypsilon/frontend-dev-bookmarks

This page is not maintained anymore, please update your bookmarks.

---

rgreenjr

-- show running queries (pre 9.2)
SELECT procpid, age(clock_timestamp(), query_start), usename, current_query 
FROM pg_stat_activity 
WHERE current_query != '<IDLE>' AND current_query NOT ILIKE '%pg_stat_activity%' 
ORDER BY query_start desc;

-- show running queries (9.2)
SELECT pid, age(clock_timestamp(), query_start), usename, query 
FROM pg_stat_activity 
WHERE query != '<IDLE>' AND query NOT ILIKE '%pg_stat_activity%' 

MohamedAlaa

tmux shortcuts & cheatsheet

start new:

tmux

start new with session name:

tmux new -s myname

jboner

Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference                           0.5 ns
Branch mispredict                            5   ns
L2 cache reference                           7   ns                      14x L1 cache
Mutex lock/unlock                           25   ns
Main memory reference                      100   ns                      20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy             3,000   ns        3 us
Send 1K bytes over 1 Gbps network       10,000   ns       10 us
Read 4K randomly from SSD*             150,000   ns      150 us          ~1GB/sec SSD