[erlang-questions] erlang:trace_pattern with {return_trace}: is match against return value possible?

[Vladimir Gordeev]

Hey,

I'm tracing http requests in my app by following pattern:

erlang:trace_pattern({lhttpc, request, 9}, [{'_', [], [{return_trace}]}],
[local]),

It works great and sends me every request and result.

The problem is that response might be quite huge (several of megabytes) and
as far as I understand, it will copy it constantly to my tracer process.

I see that I can use size() guard function in match specifications, and I
wamt replace body binary with <<"skipped">> if it's too big.

Is there a way to match against call returning value?
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