Hi Jasen! :-)

 JB> Extremely hard to do in software without interpreting the entire 
 JB> program.
Albeit slow, single-stepping the program should also work. ;) This can be
done by replacing the next instruction with an INT1 (one byte opcode) and
remembering what to put there in the INT1 handler. Under Linux, one would
use ptrace(2) instead.

Ciao
Pascal

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