Useful commands and tricks for Raspbian Wheezy & Python

Useful python tutorial sites:

http://sthurlow.com/python/

https://www.learnpython.org/

Default Pi login credentials:
User: pi
Password: raspberry

1. To start GUI write startx and to exit GUI write pkill x

2. sudo apt-get update

3. sudo apt-get upgrade

4. sudo apt-get install python-requests

5. Installing pip for python 2
    sudo apt-get install python-pip

6. Installing libdbus
    sudo apt-get install libdbus-1-dev

7. sudo pip install pathlib

8. Type ls to see the content of the current directory

9. To see available WiFi networks
    sudo iwlist wlan0 scan | grep ESSID

10. To see the current network it's connected to
      sudo iwgetid

11. sudo iwconfig

12. sudo ifconfig

13. To write python code in terminal type
      python

14. To exit type
      raise SystemExit

15. To run a python code write
      python test.py

16. To exit
      ctrl+c

16. If the python script needs admin authority or accesses GPIO then you need sudo
      sudo python test.py

17. To run the script in a separate thread
      sudo python test.py &

18. To exit
      ctrl+d

19. To see the temperature, type
      vcgencmd measure_temp

20. To configure RPi, type
      sudo raspi-config

21. To pass audio through hdmi
      Edit /boot/config.txt
      hdmi_drive = 2

22. To hard code display resolution
      Edit /boot/config.txt
      hdmi_group = 2
      hdmi_mode = 39 (for 1360x768)
      Read this link for more details
   
23. To see the current resolution setting, type
      fbset -s

24. To see the attached storage
      df

25. To unmount flash drives
      sudo umount /dev/sda1

26. Sudo raspi-config → cli
      Cli in wheezy does not auto login
      sudo nano /etc/inittab
      1:2345:respawn:/sbin/getty --autologin pi --noclear 38400 tty1

      To blank the screen after a minute →
      /etc/kbd/config
      BLANK_TIME=1
      BLANK_DPMS=off
      POWERDOWN_TIME=0 (note: not sure about this line more details here →  link)

27. To clear boot messages when starting up append this bit to .bashrc file →
      sudo clear

28. To install requests, update and upgrade first
      sudo apt-get update
      sudo apt-get upgrade
      sudo apt-get install python-requests

29. To change the keyboard setting with
      sudo raspi-config
      Select a generic keyboard and change country to US

30. print the name of my working directory
      pwd

31. To access Pi via SSL you must enable SSL from raspi-config. To find the IP address and other network related information use the command "ifconfig". To find Pi in headless mode, connect Pi with an straight ethernet cable. Start up either Find My Pi tool by adafruit or Angry IP scanner and get the IP address of the Pi. Open putty and get in using the IP address. 

32. To install PIL for working with images and icons using Tkinter for Python 2
sudo apt-get install python-imaging
sudo apt-get install python-imaging-tk

33. Tkinter won't run from cli so you will have to start the desktop interface. To run codes at start up edit .bashrc file and append the command sudo python yourTkinterTest.py to run your code. Now go to raspi-config and select boot to desktop mode. To load up the terminal automatically on desktop boot edit the following file:
sudo nano /etc/xdg/lxsession/LXDE-pi/autostart
Append the following line at the end
@lxterminal

34. To disable Xsession (Desktop) from blanking add the following lines in the file mentioned in 33
@xset s noblank
@xset s off
@xset -dpms

35. Installing  Eclipse Paho MQTT Python client library:
sudo apt-get update
sudo apt-get install python-smbus
sudo apt-get install mosquitto
git clone https://github.com/eclipse/paho.mqtt.python
cd paho.mqtt.python
sudo python setup.py install

36. To forget a network or add a new one from cmd edit the following line:
/etc/wpa_supplicant/wpa_supplicant.conf

The format is as follows:
network = {
            ssid = ""
            psk = ""
            key_mgmt = WPA-PSK
}

Check this link for details.