[WAY OT] how to gdb a running process *non-intrusively*??

[Ed Greshko]

Robert P. J. Day wrote:
>   sorry for the massively OT post but it's 3:30 am where i am, and i'd
> like to figure this out in the next hour or two.  how can i use "gdb"
> to debug a currently running process *non-intrusively* -- i.e.,
> without attaching to it which causes it to stop, even briefly?  i
> could have sworn there was a way to do that, but my memory is failing
> me at the moment.
> 
>   assume i have a symbol-laden copy of the executable, and that all i
> want to do is, in real time, print variable contents as the process
> continues to run with no interference of the process itself.  thanks
> muchly.

That would violate the Heisenberg uncertainty principle.  :-)