405 bytes added, 
19:27, 14 April 2010 You can protect a basic program by saving it with 
 save"filename",p
You can still '''run"''' a protected basic file, but can't '''load"''' and list it.
There is a way to unlock these basic files. This only works on a CPC 464 (real machine or emulator).
Type this:
 poke &ac02,&90
 poke &ac03,&c0
 poke &ac01,&c3
then '''load"''' the protected basic file.
Done.
Now you can '''list''' this program.