A good article about Git branching model

A successful Git branching model

Source: http://nvie.com/posts/a-successful-git-branching-model/

Keyboard shortcuts for symbols on Mac OS X

Degree (˚): option + k
Micro (µ): option + m
Copyright (©): option + g
Ohm (Ω): option + z
Registered (®): option + r
Trade mark (™): option + 2

Math:
Approximate (≈): option + x
PI (π): option + p
Delta (∆): option + j

Infinity (∞): option + 5
Division (÷): option + /
Not equal (≠) : option + '+'

Plus/Minus (±): option + shift + =

Square root (√): option + v

Alpha (∂): option + d

Beta (ß): option + s

Function(ƒ): option + f

Calculus (∫): option + b

Money:
Yen (¥): option + y
Pound: (£): option + 3
Euro (€): option + shift + 2

No interface available in Wireshark on Mac OS

Change the permission to 644 on the BFF (Berkeley Packet Filter) in /dev/

sudo chmod 644 /dev/bpf*

or

whoami to find out your name

sudo chown yourname:admin /dev/bp*

And restart wireshark!

USB to Serial (Console) on Mac OS X

Use the built-in "screen"

1. Install the USB to Serial driver (PL2303 Mac OS X)

2. In terminal, launch Screen and connect to device by following command (115200: baud rate)

    screen /dev/cu.usbserial 115200
or screen /dev/tty.usbserial 115200

To list the screen sessions: screen -ls   (output in format pid.tty.host)

To resume a detached session: screen -r   or  screen -x pid

Commands in 'screen':

'Control+a' and then '?' : Help

'Control+a' and then 'H' : toggle logging

'Control+a' and then 'Control+\' : Quit screen

tcpdump wirte to screen and file

Basic form:
tcpdump -i interface OPTIONS -w - | tee outputFile | tcpdump -r -

-w - : write data to stdout
tee : write data to file and its own stdout
-r - : read data from stdin

Example:
tcpdump -i enp3s0 udp and port 53 -w - | tee packet.pcap | tcpdump -nn -r -

Use iptables for CentOS 7 instead of firewalld

CentOS 7 is now using firewalld instead of iptables. To use iptables, here are the steps:

1. Disable firewalld
systemctrl disable firewalld

2. Stop firewalld
systemctrl stop firewalld

3. Install iptables-services
yum install iptables-services

4. Enable iptables
systemctl enable iptables

5. Start iptables
systemctl start iptables

 6. Configure iptables as usual (/etc/sysconfig/iptables)

Add a private key to Mac OS X KeyChain

ssh-add -K ~/.ssh/id_rsa

ps. make sure the permission of id_rsa is 600