silent1mezzo

On undoing, fixing, or removing commits in git

A git choose-your-own-adventure!

This document is an attempt to be a fairly comprehensive guide to recovering from what you did not mean to do when using git. It isn't that git is so complicated that you need a large document to take care or your particular problem, it is more that the set of things that you might have done is so large that different techniques are needed depending on exactly what you have done and what you want to have happen.

fernandoaleman

## Configure eth0
#
# vi /etc/sysconfig/network-scripts/ifcfg-eth0

DEVICE="eth0"
NM_CONTROLLED="yes"
ONBOOT=yes
HWADDR=A4:BA:DB:37:F1:04
TYPE=Ethernet
BOOTPROTO=static

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

austinmarton

/*
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 */

#include <arpa/inet.h>
#include <linux/if_packet.h>
#include <linux/ip.h>

mikesmullin

Mike's x86-64 Assembly (ASM) Notes

Assembling Binary Machine Code

Operating Modes:

These determine the assumed/default size of instruction operands, and restricts which opcodes are available, and how they are used.

Modern operating systems, booted inside Real mode,

shamil

How to mount a qcow2 disk image

This is a quick guide to mounting a qcow2 disk images on your host server. This is useful to reset passwords, edit files, or recover something without the virtual machine running.

Step 1 - Enable NBD on the Host

modprobe nbd max_part=8

protrolium

ffmpeg

Converting Audio into Different Formats / Sample Rates

Minimal example: transcode from MP3 to WMA:
ffmpeg -i input.mp3 output.wma

You can get the list of supported formats with:
ffmpeg -formats

You can get the list of installed codecs with:

dnmfarrell

An Introduction to tmux

Overview

• Terminal multiplexer
• Multiple terminals
• Panes & windows
• Maintains connections
• Configurable

fffaraz

/*
    Packet sniffer using libpcap library
*/
#include<pcap.h>
#include<stdio.h>
#include<stdlib.h> // for exit()
#include<string.h> //for memset
 
#include<sys/socket.h>
#include<arpa/inet.h> // for inet_ntoa()

zmwangx

We've been able to toggle visibility of gists since 2014 (https://github.com/blog/1837-change-the-visibility-of-your-gists), but I just noticed that I can no longer make public gists private. That is, when I edit private gists I still see the "Make Public" button, but not the other way round — there's only a "Delete" button when I edit public gists; the "Make Secret" which should be next to it (as shown in the screencast in the linked blog post) is nowhere to be found. I made a screenshot and a screencast demonstrating the issue, both of which are attached. Could you please confirm this issue? Was this an intentional change, and why? Thank you for your attention.