In home/pi
apt-get install arduino loads arduino 1.0.1 and it works from the entry in the xwindow menu
I want to upgrade to 1.0.5 and downloaded the Linux 32 bit version from Arduino.cc
The compressed file was unpacked into a temporary folder in Pi /tmp
The Arduino IDE File folder names look good in /tmp
So to get to the point, how do I upgrade the old version 1.0.1 IDE ?
You should unpack it somewhere besides /tmp. That directory is deleted now and then.
Once you unpack it, you should be able to navigate to that directory, and in the arduino directory, there is an executable file named arduino. Run it. Something like this
cd /tmp/arduino
./arduino