The situation is the following: I'm uploading code to Arduino board using USB programmer which communicates with the board via Tx/Rx serial (so boot-loader remains on the board).
I want to prevent reading of the code from Arduino board. As I've found I should set fuses to disable reading. Will it work for the case of boot-loader is on the board? I assume if boot-loader allows uploading of the code it may allow downloading too.
Another question - do I need SPI programmer to modify fuses or serial USB programmer will work as well?