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> eBPF on Linux automatically handles both existing and new processes

Without knowing your particular case, DTrace does too - it’d certainly be tricky to use if you’re trying to debug software that “instantly crashes on startup” if it couldn’t do that. “execname” (not “pid”) is where I’d look, or perhaps that part of the predicate is skipable; regardless, should be possible.




For example I used something like "pid:module:funcname:entry" probe for userspace things (not pid$123 or pid$target, just pid to catch all PIDs using the module/funcname of interest). And back when I tested, it didn't automatically catch any new PIDs so these probes were not fired for them unless I restarted my DTrace script (but it was probably year <2010 when I last tested it).

Execname is a variable in DTrace and not a probe (?), so how would it help with automatically attaching to new PIDs? Now that I recall more details, there was no issue with statically defined kernel "fbt" probes nor "profile", but the userspace pid one was where I hit this limitation.


> Execname is a variable in DTrace and not a probe (?), so how would it help with automatically attaching to new PIDs?

You're correct, and I may have provided "a solution" to a misunderstanding of your problem - I don't think the "not matching new procs/pids" is inherent in DTrace, so indeed you might have run into an implementation issue (as it was 15 years ago). I misunderstood you as perhaps using a predicate matching a specific pid; my fault.




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