Linux / Raspberry Pi Tips:

Set Timezone from command line
sudo dpkg-reconfigure tzdata

Show time
sudo date

Enable FTP server on Pi

If you transfer a shell script from one machine to another it may not work even after chmod 755 - if so try this fix:
sed -i 's/\r//' filename
this command fixes the end of line/file markers and allows it to work

To keep an SSH session alive use "screen" - see:
Very useful when starting a Python session from SSH and then disconnecting  - tutorial here:
nohup python &      keeps the process running after logout
stop with    killall python

Using Knoppix to rescue a dead Windows PC 

Using Knoppix to clone a hard drive

Installing Knoppix on a hard drive (use the 3.3 and above:  sudo knoppix-installer     after Ctrl-Alt-F1 to get to root)

Troubleshooting tips (screen resolution change on boot, etc)

Automatically login - see:

to Kill a process do the following:
    use    ps -ef   to list all processes - note the one you want to kill and its PID
    type   sudo kill -9 whateverthePIDis

Wireless setup- notes based on this web page:

pi@raspberrypi ~ $ cat /etc/network/interfaces
auto lo
iface lo inet loopback
#iface eth0 inet dhcp
#auto lo
iface lo inet loopback
iface eth0 inet dhcp
allow-hotplug wlan0
iface wlan0 inet dhcp
wireless-essid main
wireless-key abcdeabcde

#wpa-roam /etc/wpa_supplicant/wpa_supplicant.conf
#wireless-power off
#iface default inet dhcp

#wpa-roam /etc/wpa_supplicant/wpa_supplicant.conf
iface default inet dhcp

iface eth0 inet static





Sending mail from command line on Pi has good instructions

this works well, too
a sample Python file is here - it works....

Testing for new IP routine is called with this argument  os.system("sudo python 1")
File that is called is

web page it calls contains only this code
<?php echo $_SERVER['REMOTE_ADDR']; ?>
which returns only the bare IP address -

my /etc/ssmtp/ssmtp.conf  looks like this:

# Config file for sSMTP sendmail
# The person who gets all mail for userids < 1000
# Make this empty to disable rewriting.

# The place where the mail goes. The actual machine name is required no
# MX records are consulted. Commonly mailhosts are named

# Where will the mail seem to come from?

# The full hostname

# Are users allowed to set their own From: address?
# YES - Allow the user to specify their own From: address
# NO - Use the system generated From: address

# Use SSL/TLS before starting negotiation

# Username/Password


Miscellaneous commands that I always forget:

nano cut / paste block
Alt + A = Mark (or select) text
Alt + 6 = Copy text in the buffer
Ctrl + U = Past the text from the buffer

ifconfig - get IP address

iwconfig - wireless network info

sudo raspi-config - bring up Raspberry Pi config menu

Halfacree, Gareth; Upton, Eben (2012-08-30). Raspberry Pi User Guide (Kindle Location 1632). John Wiley and Sons. Kindle Edition.

rm  -  remove file

df - h  or  df -k  - free disk space

rmdir  - remove directory

ls -lh    - show directory info - detailed
ls -lt  - show directory sorted by time
ls -ltr  - same but reverse order
ls -ltS   -sort by size
ls -ltSr  - same but reverse order

top   - q to exit - shows resources being used on system

Lots more: