Zhang Bo wrote:
> thank you very much! I followed your advice. It works!
> 
> Another question is how to set breakpoints?
> 
> $gdb ruby
> $run -Ilib my_test.rb
> ......
> ......
> what about next? how to set breakpoints for my own program? how to step 
> through?

At a gdb prompt, type "help".

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