Debugging ExternalObject libraries loaded in via ExtendScript - trouble seeing debug logging.

I'm successfully loading an external library via ExtendScript's ExternalObject and I can even step through the bulk of the implementation but I'm having issues finding where my debug output is going to.

I'm running Xcode (MacOS) and looking at the Console panel for output of fprintf(stderr,...) statements and I'm not seeing any output there. I'm running similar code using fprintf in Xcode and the output is in the Console panel as expected so I'm thinking that maybe the Premiere Pro process is somehow capturing (and killing?) any output to stderr.

Is there a switch to allow for debug logging when running Premiere Pro? Or is there a specific place where I can find debug logging (not finding my messages in /var/log/system.log)?

I'm ultimately experiencing an issue with my external libraries when running in the context of Adobe Premeire Pro.  Stepping through the code in the debugger is proving problematic so I'd like to use the old-school technique of logging my way through to help isolate my real problem.